Search

Objectives: Type-2 Diabetes mellitus (T2DM) increases both the patient risk of cardiovascular disease (CVD) and renal outcomes, such as chronic kidney disease (CKD). Recent clinical trials of the glucose-lowering drug-class of sodium-glucose co-transporter-2 inhibitors (SGLT2is) have shown benefits in preventing CVD events and progression of CKD, leading to an update of the Dutch T2DM treatment guideline for patients at risk. The aim of this study is to assess the health and economic impact of the guideline-recommended utilization of SGLT2is in the Netherlands. Methods: The patient population at risk was determined by multiplying Dutch T2DM prevalence rates with the total numbers of inhabitants of the Netherlands in 2020. Subsequently, two analyses, comparing a treatment setting before and after implementation of the new guideline for SGLT2is, were conducted. Clinical and adverse event rates in both settings as well as direct healthcare costs were sourced from the literature. Total costs were calculated by multiplying disease prevalence, event rates and costs associated to outcomes. One-time disutilities per event were included to estimate the health impact. The potential health and economic impact of implementing the updated guideline was calculated. Results: Using a 5-year time horizon, the guideline-suggested utilization of SGLT2is resulted in a health impact equal to 4835 quality adjusted life years gained (0.0031 per patient per year) and €461 million cost-savings. The costs of treatment with SGLT2is were €813 million. Hence the net budget impact was €352 million for the total Dutch T2DM population, which translated to €0,57 per patient per day. Conclusion: SGLT2is offer an option to reduce the number of CVD and CKD related events and associated healthcare costs and health losses in the Netherlands. Further research is needed to include the benefits of improved T2DM management options from a broader societal perspective.Highlights The glucose-lowering drug-class of sodium-glucose co-transporter-2 inhibitors (SGLT2is) has shown benefits in preventing cardiovascular events and progression of kidney disease in patients with type-2 diabetes leading to a revision of the respective Dutch treatment guideline. The 5-year budget impact of the adoption of SGLT2is in the new treatment guideline was equal to €352 million or €0.57 per patient per day, with a total of 4385 quality adjusted life years gained. The introduction of SGLT2is for Dutch type-2 diabetes patients has the potential to substantially reduce the number of cardiovascular as well as renal disease events and related healthcare costs while also delivering a health benefit.

Aims The COVID-19 pandemic impacted diabetes care by reducing diabetes outpatient visits and diabetes-related screening due to healthcare allocation. Yet the impact of COVID-19 on diabetes outpatients has not been extensively evaluated. This study aimed to assess the effect of the COVID-19 pandemic on all aspects of outpatient diabetes care, particularly diagnostics and intermediate outcomes. Methods This observational cohort study included 8,442 diabetes patients in the Dutch Pediatric and Adult Registry of Diabetes (DPARD) visiting diabetes outpatient clinics in 2019 and 2021. A mixed-effects regression analysis was used to examine differences in target achievement of HbA1c, BMI, blood pressure, LDL-cholesterol, eGFR, and the difference in mean HbA1c between 2019 and 2020 among n=1,426 outpatients who visited in both years. Analyses were adjusted for age, sex, and BMI Results A 22.7% (21.6 - 23.8%, pConclusions The COVID pandemic impacted Dutch diabetes outpatient care by reducing patient volume by 22.7%. Among patients who received outpatient care both before and during the pandemic period, HbA1c control and blood pressure control enhanced during the pandemic. Re-evaluation of current diabetes outpatient care organization is warranted to ensure optimal diabetes care in future times.

Objective: In mice fed a high-fat diet, impairment of insulin signaling in endothelium is an early phenomenon that precedes decreased insulin sensitivity of skeletal muscle, adipose tissue, and liver. We assessed in humans whether short-term overfeeding affects insulin-induced microvascular recruitment in skeletal muscle and adipose tissue before changes occur in glucose uptake and lipolysis. Approach and Results: Fifteen healthy males underwent a hypercaloric and subsequent hypocaloric diet intervention. Before, during, and after the hypercaloric diet, and upon return to baseline weight, all participants underwent (1) a hyperinsulinemic-euglycemic clamp to determine insulin-induced glucose uptake and suppression of lipolysis (2) contrast-enhanced ultrasonography to measure insulin-induced microvascular recruitment in skeletal muscle and adipose tissue. In addition, we assessed insulin-induced vasodilation of isolated skeletal muscle resistance arteries by pressure myography after the hypercaloric diet in study participants and controls (n=5). The hypercaloric diet increased body weight (3.5 kg; P P P =0.041) and decreased the ratio between skeletal muscle and adipose tissue microvascular blood volume during hyperinsulinemia ( P =0.019). Insulin-induced vasodilation of isolated skeletal muscle arterioles was significantly lower in participants compared with controls ( P Conclusions: In lean men, short-term overfeeding reduces insulin-induced vasodilation of skeletal muscle resistance arteries and shifts the distribution of tissue perfusion during hyperinsulinemia from skeletal muscle to adipose tissue without affecting glucose uptake and lipolysis. Registration: URL: https://www.clinicaltrials.gov . Unique identifier: NCT02628301.

Sodium-glucose cotransporter 2 (SGLT2) inhibitors include a relatively new class of glucose-lowering drugs that reduce plasma glucose concentrations by inhibiting proximal tubular reabsorption of glucose in the kidney, while increasing its excretion in urine. Recent large randomised controlled trials have demonstrated that many of these agents reduce the occurrence of major adverse cardiovascular events, hospitalisation for heart failure, cardiovascular death and/or chronic kidney disease progression in patients with and without type 2 diabetes mellitus (DM2). Given their unique insulin-independent mode of action and favourable efficacy and adverse-event profile, SGLT2 inhibitors are promising and they offer an interesting therapeutic approach for the cardiologist to incorporate into routine practice. However, despite accumulating data supporting this class of therapy, cardiologists infrequently prescribe SGLT2 inhibitors, potentially due to a lack of familiarity with their use and the reticence to change DM medication. Here, we provide an up-to-date practical guide highlighting important elements of treatment initiation based on real-world evidence and expert opinion. We describe how to change DM medication, including insulin dosing when appropriate, and how to anticipate any adverse events based on real-world experience in patients with DM2 in the Meander Medical Centre in Amersfoort, the Netherlands. This includes a simple algorithm showing how to initiate SGLT2 inhibitor treatment safely, while considering the consequence of the glucosuric effects of these inhibitors for the individual patient. Supplementary Information The online version of this article (10.1007/s12471-021-01580-9) contains supplementary material, which is available to authorized users.

Objective assess how many patients with low ambulatory diastolic blood pressure (DBP) are not identified when relying on office DBP alone, and thus have ‘masked diastolic hypotension’. Design cross-sectional, retrospective cohort study. Setting academic hospital. Subjects 848 patients treated for hypertension who received ambulatory blood pressure monitoring (ABPM). Methods cut-off value between on- and off-target systolic blood pressure (SBP): 140 mmHg. Cut-off for low office and/or ambulatory DBP: DBP ≤ 70 mmHg. ‘Masked diastolic hypotension’ was defined as office DBP > 70 mmHg and mean ambulatory DBP ≤ 70 mmHg. Results mean age of the sample was 60 ± 13 years, 50% was female, 37% had diabetes, 42% preexisting cardiovascular disease (CVD), mean office blood pressure (BP) was 134/79 mmHg. In all patients (n = 848), low office DBP was present in n = 84(10%), while n = 183(22%) had low ambulatory DBP. In all patients with normal-to-high office DBP (n = 764), n = 122(16%) had ‘masked diastolic hypotension’. In this group, ambulatory DBP was 14–19 mmHg lower than office DBP. Patients with low ambulatory DBP were older, had more (cardiovascular) comorbidities, and used more (antihypertensive) drugs. Antihypertensive drugs were lowered or discontinued in 30% of all patients with ‘masked diastolic hypotension’ due to side effects. Conclusions ‘masked diastolic hypotension’ is common among patients treated for hypertension, particularly in older patients with CVD (e.g. coronary artery disease, diabetes), patient groups in which the European Society of Cardiology/Hypertension guideline advises to prevent low DBP. Although it remains to be examined at which BP levels the harms of low DBP outweigh the benefits of lowering SBP, our observations are aimed to increase awareness among physicians.

Aims The global epidemic of diabetes mellitus continues to expand, including its large impact on national health care. Measuring diabetes outcomes and their causes of variation highlights areas for improvement in care and efficiency gains; large registries carry this potential. By means of a systematic review, we aimed to give an overview of national registries worldwide by quantifying their data and assessing their influence on diabetes care. Methods The literature on MEDLINE up to March 31, 2020, was searched, using keywords diabetes mellitus, national, registry, registration, and/or database. National disease-specific registries from corresponding articles were included. Database characteristics and clinical variables were obtained. All registries were compared to the ICHOM standard set of outcomes. Results We identified 12 national clinical diabetes registries, comprising a total of 7,181,356 diabetic patients worldwide. Nearly all registries recorded weight, HbA1c, lipid profile, and insulin treatment; the recording of other variables varied to a great extent. Overall, registries corresponded fairly well with the ICHOM set. Most registries proved to monitor and improve the quality of diabetes care using guidelines as a benchmark. The effects on national healthcare policy were more variable and often less clear. Conclusions National diabetes registries confer clear insights into diagnostics, complications, and treatment. The extent to which registries influenced national healthcare policy was less clear. A globally implemented standard outcome set has the potential to improve concordance between national registries, enhance the comparison and exchange of diabetes outcomes, and allocate resources and interventions where most needed.

Background and Aims: Metabolic-associated fatty liver disease (MAFLD) is driven by high caloric intake and sed-entary lifestyle. Migration towards high income countries may induce these driving factors; yet, the influence of such on the prevalence of MAFLD is clearly understudied. Here, we investigated the Fatty Liver Index (FLI), a proxy of steatosis in MAFLD, after migration of Ghanaian sub-jects. Methods: Cross-sectional data of 5282 rural, urban and migrant participants from the Research on Obesity and Diabetes among African Migrants (also known as RODAM) study were analyzed with logistic regression for geographi-cal differences in FLI and associations with type 2 diabetes mellitus (T2DM), waist-to-hip ratio, and 10-year predicted risk of atherosclerotic cardiovascular disease (ASCVD). Results: Both FLI and the proportion with an FLI indica-tive of MAFLD steatosis (FLI ≥60) were higher in migrants compared with non-migrants. Prevalence of elevated FLI (FLI ≥60) in non-migrant males was 4.2% compared to 28.9% in migrants. For females, a similar gradient was ob-served, from 13.6% to 36.6% respectively. Compared to rural residents, the odds for a FLI ≥60 were higher in migrants living in urban Europe (odds ratio [OR] 9.02, 95% confidence interval [CI]: 5.02–16.20 for men, and 4.00, 95% CI: 3.00–5.34 for women). Compared to controls, the ORs for FLI ≥60 were 2.43 (95% CI: 1.73–3.41) for male T2DM cases and 2.02 (95% CI: 1.52–2.69) for female T2DM cases. One-unit higher FLI was associated with an elevated (≥7.5%) 10-year ASCVD risk (OR: 1.051, 95% CI: 1.041–1.062 for men, and 1.020, 95% CI: 1.015–1.026 for women). Conclusions: FLI as a proxy for MAFLD increased stepwise in Ghanaians from rural areas, through urban ar-eas, to Europe. Our results clearly warrant awareness for MAFLD in migrant population as well as confirmation with imaging modalities.

Thus far, the association between residual vein occlusion and immediate compression therapy and postthrombotic syndrome is undetermined. Therefore, we investigated whether compression therapy immediately after diagnosis of deep vein thrombosis affects the occurrence of residual vein obstruction (RVO), and whether the presence of RVO is associated with postthrombotic syndrome and recurrent venous thromboembolism. In a prespecified substudy within the IDEAL (individualized duration of elastic compression therapy against long-term duration of therapy for prevention of postthrombotic syndrome) deep vein thrombosis (DVT) study, 592 adult patients from 10 academic and nonacademic centers across The Netherlands, with objectively confirmed proximal DVT of the leg, received no compression or acute compression within 24 hours of diagnosis of DVT with either multilayer bandaging or compression hosiery (pressure, 35 mm Hg). Presence of RVO and recurrent venous thromboembolism was confirmed with compression ultrasonography and incidence of postthrombotic syndromeas a Villalta score of at least 5 at 6 and 24 months. The average time from diagnosis until assessment of RVO was 5.3 (standard deviation, 1.9) months. A significantly lower percentage of patients who did receive compression therapy immediately after DVT had RVO (46.3% vs 66.7%; odds ratio, 0.46; 95% confidence interval, 0.27-0.80; P = .005). Postthrombotic syndrome was less prevalent in patients without RVO (46.0% vs 54.0%; odds ratio, 0.65; 95% confidence interval, 0.46-0.92; P = .013). Recurrent venous thrombosis showed no significant association with RVO. Immediate compression should therefore be offered to all patients with acute DVT of the leg, irrespective of severity of complaints. This study was registered at ClinicalTrials.gov (NCT01429714) and the Dutch Trial registry in November 2010 (NTR2597).

Background: Therapy with elastic compression stockings has been the cornerstone for prevention of post-thrombotic syndrome for decades in patients after acute deep venous thrombosis. It is uncertain who benefits most from therapy, and what the optimum duration of therapy should be. We therefore aimed to assess the safety and efficacy of individualised duration of compression therapy versus the standard duration of 24 months following an initial treatment period of 6 months. Methods: We did a multicentre, randomised, single-blind, allocation-concealed, non-inferiority trial at 12 hospitals in the Netherlands and two in Italy. We randomly assigned patients (1:1) with acute proximal deep vein thrombosis of the leg and without pre-existent venous insufficiency (Clinical Etiological Anatomical and Pathophysiological score

Preclinical studies have suggested that polyphenols extracted from red wine (RWPs) favourably affect insulin sensitivity, but there is controversy over whether RWPs exert similar effects in humans. The aim of the present study was to determine whether RWPs improve insulin sensitivity in obese volunteers. Obese (body mass index >30 kg/m2) volunteers were randomly allocated to RWPs 600 mg/d (n = 14) or matched placebo (n = 15) in a double-blind parallel-arm study for 8 weeks. The participants were investigated at baseline and at the end of the study. Insulin sensitivity was determined using a hyperinsulinaemic-euglycaemic clamp (M-value), a mixed-meal test (Matsuda index), and homeostatic model assessment of insulin resistance (HOMA-IR). RWPs elicited no significant changes in M-value (RWP group: median [interquartile range; IQR] baseline 3.0 [2.4; 3.6]; end of study 3.3 [2.4; 4.8] vs placebo group: median [IQR] baseline 3.4 [2.8; 4.4]; end of study 2.9 [2.8; 5.9] mg/kg/min; P =.65), in Matsuda index (RWP group: median [IQR] baseline 3.3 [2.2; 4.8]; end of study 3.6 [2.4; 4.8] vs placebo group: median [IQR] baseline 4.0 [3.0; 6.0]; end of study 4.0 [3.0; 5.2]; P =.88), or in HOMA-IR. This study showed that 8 weeks of RWP supplementation did not improve insulin sensitivity in 29 obese volunteers. Our findings were not consistent with the hypothesis that RWPs ameliorate insulin resistance in human obesity.

After food ingestion, macronutrients are transported to and stored in the skeletal muscle and adipose tissue. They can be subsequently used as an energy source in times of energy deprivation. Uptake of these nutrients in myocytes and adipocytes depends largely on adequate tissue perfusion. Interestingly, insulin is able to dilate skeletal muscle arterioles, which facilitates the delivery of macronutrients and insulin itself to muscle tissue. Insulin-stimulated skeletal muscle perfusion is impaired in several insulin-resistant states and is believed to contribute to impaired skeletal muscle glucose uptake and consequently impaired whole-body glucose disposal. Insulin-resistant individuals also exhibit blunted postprandial adipose tissue perfusion. However, the relevance of this impairment to metabolic dysregulation is less clear. In this review, we provide an overview of adipose tissue perfusion in healthy and insulin-resistant individuals, its regulation among others by insulin, and the possible influences of impaired adipose tissue perfusion on whole-body insulin sensitivity. Finally, we propose a novel hypothesis that acute overfeeding impacts distribution of macronutrients by reducing skeletal muscle perfusion, while adipose tissue perfusion remains intact. Visual Overview— An online visual overview is available for this article.

Background/Objectives:Epidemiological, in vitro and animal studies suggest that grape polyphenols, such as those present in wine, have favorable effects on the metabolic syndrome. However, controversy remains whether treatment with grape polyphenols is effective in humans. Here, we aimed to systemically review the effects of grape polyphenols on metabolic syndrome components in humans.Subjects/Methods:We systematically searched Medline, EMBASE and the Cochrane database for all clinical trials assessing the effects of grape polyphenols on insulin sensitivity, glycemia, blood pressure or lipid levels. We screened all titles and reviewed abstracts of potentially relevant studies. Full papers were assessed for eligibility and quality-rated according to the Jadad scale by two independent assessors.Results:Thirty-nine studies met the eligibility criteria. In individuals without component criteria of the metabolic syndrome, only low- and medium-quality studies were found with primarily neutral results. In individuals with the metabolic syndrome or related conditions, one of two high-quality studies suggested improvement in insulin sensitivity. Glycemia was improved in 2 of 11 lower-quality studies and 2 of 4 high-quality studies. Seven of 22 studies demonstrated a significant decrease in blood pressure, but only one was of high quality. Two of four high-quality studies pointed towards effects on total cholesterol while other lipidemic parameters were not affected.Conclusions:No compelling data exist that grape polyphenols can positively influence glycemia, blood pressure or lipid levels in individuals with or without the metabolic syndrome. Limited evidence suggests that grape polyphenols may improve insulin sensitivity.European Journal of Clinical Nutrition advance online publication, 1 February 2017; doi:10.1038/ejcn.2016.227.

Background: Dutch cardiovascular risk management guidelines state almost every older adult (≥70 years) is eligible for a lipid lowering drug (LLD). However, life expectancy, frailty or comorbidities may influence this treatment decision. Objective: investigate how many older adults, according to age, frailty (Drubbel-frailty index) and comorbidities were prescribed LLDs. Methods: data of 244,328 adults ≥70 years from electronic health records of 415 Dutch general practices from 2011-15 were used. Number of LLD prescriptions in patients with (n = 55,309) and without (n = 189,019) cardiovascular disease (CVD) was evaluated according to age, frailty and comorbidities. Results: about 69% of adults ≥70 years with CVD and 36% without CVD were prescribed a LLD. LLD prescriptions decreased with age; with CVD: 78% aged 70-74 years and 29% aged ≥90 years were prescribed a LLD, without CVD: 37% aged 70-74 years and 12% aged ≥90 years. In patients with CVD and within each age group, percentage of LLD prescriptions was 20% point(pp) higher in frail compared with non-frail. In patients without CVD, percentage of LLD prescriptions in frail patients was 11pp higher in adults aged 70-74 years and 40pp higher in adults aged ≥90 years compared to non-frail. Similar trends were seen in the analyses with number of comorbidities. Conclusion: in an older population, LLD prescriptions decreased with age but - contrary to our expectations - LLD prescriptions increased with higher frailty levels.

IntroductionHodgkin’s lymphoma (HL) has become the prototype of a curable disease. However, many young survivors suffer from late adverse effects of treatment. Both chemotherapy (CT) and radiotherapy (RT) may induce primary ovarian insufficiency (POI), which has been associated with reduced bone mineral density (BMD), neurocognitive dysfunction and possibly cardiovascular disease (CVD). While the general assumption is that POI increases CVD risk, other hypotheses postulate reverse causality, suggesting that cardiovascular risk factors determine menopausal age or that biological ageing underlies both POI and CVD risk. None of these hypotheses are supported by convincing evidence. Furthermore, most studies on POI-associated conditions have been conducted in women with early natural or surgery-induced menopause with short follow-up times. In this study, we will examine the long-term effects of CT-induced and/or RT-induced POI on BMD, cardiovascular status, neurocognitive function and quality of life in female HL survivors.Methods and analysisThis study will be performed within an existing Dutch cohort of HL survivors. Eligible women were treated for HL at ages 15–39 years in three large hospitals since 1965 and survived for ≥8 years after their diagnosis. Women visiting a survivorship care outpatient clinic will be invited for a neurocognitive, cardiovascular and BMD assessment, and asked to complete several questionnaires and to provide a blood sample. Using multivariable regression analyses, we will compare the outcomes of HL survivors who developed POI with those who did not. Cardiovascular status will also be compared with women with natural POI.Ethics and disseminationThis study has been approved by the Institutional Review Board of the Netherlands Cancer Institute and has been registered at ‘Toetsingonline’ from the Dutch Central Committee on Research involving Human Subjects (file no. NL44714.031.13). Results will be disseminated through peer-reviewed publications and will be incorporated in follow-up guidelines for HL survivors.

Insulin-mediated microvascular recruitment (IMVR) regulates delivery of insulin and glucose to insulin-sensitive tissues. We have previously proposed that perivascular adipose tissue (PVAT) controls glucose metabolism and vascular function through outside-to-inside communication and through vessel-to-vessel, or “vasocrine” signaling. Here, we studied this hypothesis in mice by examining effects of removal of local intramuscular PVAT on muscle blood flow and glucose metabolism. Using the hyperinsulinemic, euglycemic clamp (HEC) in combination with positron emission tomography, we found that local PVAT removal transiently reduces muscle glucose uptake by ±50 percent. Contrast-enhanced ultrasonography and intravital microscopy of the gracilis artery (GA) during the HEC showed that PVAT removal abolishes insulin-induced increases in GA diameter and abrogated insulin-stimulated muscle blood volume (microvascular recruitment or IMVR). The effect of PVAT on IMVR was mediated by distinct microvessels or anastomoses, which we showed using lightsheet microscopy of mice expressing mCherry in endothelial cells. Proteomics analysis revealed that PVAT removal significantly alters expression of 109 of 1719 detected proteins in muscle. Observed changes in protein expression included reduction of a mitochondrial protein cluster and of vesicle-associated membrane protein 5 (Vamp5), involved in Glut4 trafficking. In conclusion, we have found that PVAT within muscle regulates muscle perfusion, glucose uptake and muscle protein expression, communicating with the distal microcirculation via microvascular anastomoses. These data highlight the importance of PVAT in vascular and metabolic physiology, and are relevant for type 2 diabetes and associated muscle dysfunction. Disclosure A.H. Turaihi: None. E.H. Serne: None. C. Molthoff: None. M.T. Goumans: None. C.J. Jimenez: None. J.S. Yudkin: None. Y.M. Smulders: None. V.W. van Hinsbergh: None. E.C. Eringa: None.

Objective: Cognitive impairments in type 1 diabetes may result from hyperglycemia-associated cerebral microangiopathy. In this study we aimed to identify cerebral microangiopathy and skin microvascular dysfunction - as surrogate marker for generalized microvascular function - as predictors of cognitive decline over time. Research Design and Methods: Twenty-five type 1 diabetes patients and 25 matched healthy controls underwent neurocognitive testing at baseline and after follow-up (mean duration of 3.8±0.8 years). At baseline, 1.5 T cerebral magnetic resonance imaging was used to detect white matter lesions (WML) and cerebral microbleeds. In addition, skin capillary perfusion was assessed by means of capillary microscopy. Multiple linear regression analysis was performed to examine if cerebral microangiopathy and capillary perfusion were associated with changes in cognitive performance. Results: In type 1 diabetes patients, but not in healthy controls, the presence of WML (ß=-0.419;p=0.037) as well as lower skin capillary perfusion (baseline: ß=0.753;p Conclusions: In type 1 diabetes patients, presence of WML and lower skin capillary perfusion predict poorer general cognitive ability over time. The relationship between WML and cognitive decline was significantly reduced when adjusting for capillary perfusion, suggesting that generalized microvascular dysfunction at least partly underlies WML-associated cognitive decline. Disclosure A.L. Emanuel: None. E. van Duinkerken: None. M.P. Wattjes: Consultant; Self; Biogen. Speaker's Bureau; Self; Janssen Pharmaceuticals, Inc.. Consultant; Self; Roche Pharma, Sanofi Genzyme. M. Klein: None. F. Barkhof: None. F.J. Snoek: None. E.C. Eringa: None. R. Ijzerman: Research Support; Self; AstraZeneca. E.H. Serne: None.

Introduction: Insulin signaling in adipose tissue has been shown to regulate insulin's effects in muscle. In muscle, perivascular adipose tissue (PVAT) and vascular insulin signaling regulate muscle perfusion. Insulin receptor substrate (IRS) 2 has been shown to control adipose tissue function and glucose metabolism, and here we tested the hypothesis that IRS2 mediates insulin's actions on the vessel wall as well as the vasoactive properties of PVAT. Methods: We studied PVAT and muscle resistance arteries (RA) from littermate IRS2+/+ and IRS2-/- mice and vasoreactivity by pressure myography, vascular insulin signaling, adipokine expression, and release and PVAT morphology. As insulin induced constriction of IRS2+/+ RA in our mouse model, we also exposed RA's of C57/Bl6 mice to PVAT from IRS2+/+ and IRS2-/- littermates to evaluate vasodilator properties of PVAT. Results: IRS2-/- RA exhibited normal vasomotor function, yet a decreased maximal diameter compared to IRS2+/+ RA. IRS2+/+ vessels unexpectedly constricted endothelin-dependently in response to insulin, and this effect was absent in IRS2-/- RA due to reduced ERK1/2activation. For evaluation of PVAT function, we also used C57/Bl6 vessels with a neutral basal effect of insulin. In these experiments insulin (10.0 nM) increased diameter in the presence of IRS2+/+ PVAT (17 ± 4.8, p = 0.014), yet induced a 10 ± 7.6% decrease in diameter in the presence of IRS2-/- PVAT. Adipocytes in IRS2-/- PVAT (1314 ± 161 μm2) were larger (p = 0.0013) than of IRS2+/+ PVAT (915 ± 63 μm2). Adiponectin, IL-6, PAI-1 secretion were similar between IRS2+/+ and IRS2-/- PVAT, as were expression of pro-inflammatory genes (TNF-α, CCL2) and adipokines (adiponectin, leptin, endothelin-1). Insulin-induced AKT phosphorylation in RA was similar in the presence of IRS2-/- and IRS2+/+ PVAT. Conclusion: In muscle, IRS2 regulates both insulin's vasoconstrictor effects, mediating ERK1/2-ET-1 activation, and its vasodilator effects, by mediating the vasodilator effect of PVAT. The regulatory role of IRS2 in PVAT is independent from adiponectin secretion.

Objective— The insulinotropic gut–derived hormone glucagon-like peptide-1 (GLP-1) increases capillary perfusion via a nitric oxide–dependent mechanism in rodents. This improves skeletal muscle glucose use and cardiac function. In humans, the effect of clinically used GLP-1 receptor agonists (GLP-1RAs) on capillary density is unknown. We aimed to assess the effects of the GLP-1RA exenatide on capillary density as well as the involvement of nitric oxide in humans. Approach and Results— We included 10 healthy overweight men (age, 20–27 years; body mass index, 26–31 kg/m 2 ). Measurements were performed during intravenous infusion of placebo (saline 0.9%), exenatide, and a combination of exenatide and the nonselective nitric oxide–synthase inhibitor l - N G -monomethyl arginine. Capillary videomicroscopy was performed, and baseline and postocclusive (peak) capillary densities were counted. Compared with placebo, exenatide increased baseline and peak capillary density by 20.1% and 8.3%, respectively (both P =0.016). Concomitant l - N G -monomethyl arginine infusion did not alter the effects of exenatide. Vasomotion was assessed using laser Doppler fluxmetry. Exenatide nonsignificantly reduced the neurogenic domain of vasomotion measurements ( R =−5.6%; P =0.092), which was strongly and inversely associated with capillary perfusion ( R =−0.928; P =0.036). Glucose levels were reduced during exenatide infusion, whereas levels of insulin were unchanged. Conclusions— Acute exenatide infusion increases capillary perfusion via nitric oxide–independent pathways in healthy overweight men, suggesting direct actions of this GLP-1RA on microvascular perfusion or interaction with vasoactive factors.

Essentials The value of compression therapy in acute phase of deep vein thrombosis is still unclear. Patients with deep vein thrombosis received acute compression hosiery, bandaging, or none. Acute compression reduces irreversible skin signs related to post thrombotic syndrome. Compression hosiery may be the preferred choice for the acute phase. Summary: Background The effectiveness of compression therapy in the acute phase of deep vein thrombosis (DVT) is not yet determined. Objectives To investigate the impact of compression therapy in the acute phase of DVT on determinants of the Villalta score, health-related quality of life (HRQOL), and costs. Patients/Methods Eight hundred and sixty-five patients with proximal DVT (substudy of the IDEAL DVT study) received, immediately after DVT diagnosis, either no compression, multilayer bandaging, or hosiery. In the acute phase and 3 months after diagnosis, HRQOL was determined by use of the EQ-5D, SF6D, and VEINES-QoL intrinsic method (VEINES-QoLint). At 3 months, signs and symptoms were assessed for the total and separate items of the Villalta score, and healthcare costs were calculated. Results The compression groups had lower overall objective Villalta scores than the no-compression group (1.47 [standard deviation (SD) 1.570] and 1.59 [SD 1.64] versus 2.21 [SD 2.15]). The differences were mainly attributable to irreversible skin signs (induration, hyperpigmentation, and venectasia) and pain on calf compression. Subjective and total Villalta scores were similar across groups. Differences in HRQOL were only observed at 1 month; HRQOL was better for hosiery (EQ-5D 0.86 [SD 0.18]; VEINES-QoLint 0.66 [SD 0.18]) than for multilayer compression bandaging (EQ-5D 0.81 [SD 0.23; VEINES-QoLint 0.62 [SD 0.19]). Mean healthcare costs per patient were €417.08 (€354.10 to €489.30) for bandaging, €114.25 (€92.50 to €198.43) for hosiery, and €105.86 (€34.63 to €199.30) for no compression. Conclusions Initial compression reduces irreversible skin signs, edema, and pain on calf compression. Multilayer bandaging is slightly more effective than hosiery, but has substantially higher costs, without a gain in HRQOL. From a patient and economic perspective, compression hosiery would be preferred when initial compression is applied. Trial registration: IDEAL DVT study ClinicalTrials.gov number, NCT01429714.

Sleep and sleep disorders are related to cardiovascular disease, and microvascular function is an early cardiovascular disease marker. Therefore, the relationship of sleep (measured in sleep quality and duration) with microvascular function was examined in healthy adults. Sleep quality was assessed with the validated Sleep Wake Experience List (SWEL) questionnaire. Duration of sleep was self-reported in an additional question. Microvascular function was measured using nailfold capillaroscopy. Linear regression analyses were used to examine the relationship between sleep and microvascular function. Potential confounders included physical activity, smoking, blood pressure, body mass index and several biochemical parameters. Analyses were performed in 259 participants (116 men). For women reporting insufficient (

OBJECTIVE This study investigated whether the relationship between neuropathy and microvascular dysfunction in patients with type 2 diabetes is independent of diabetes-related factors. For this purpose, we compared skin microvascular function in patients with type 2 diabetes with that of patients with cryptogenic axonal polyneuropathy (CAP), a polyneuropathy of unknown etiology. RESEARCH DESIGN AND METHODS Cross-sectional information was collected from 16 healthy controls (HCs), 16 patients with CAP, 15 patients with type 2 diabetes with polyneuropathy (DPN), and 11 patients with type 2 diabetes without polyneuropathy. Axonal degeneration was assessed with skin biopsy and nerve conduction studies. Microvascular skin vasodilation was measured using laser Doppler fluxmetry combined with iontophoresis of acetylcholine (ACh) and sodium nitroprusside (SNP). RESULTS Patients with CAP and DPN demonstrated a similar decrease in intraepidermal nerve fiber density and sural sensory nerve action potential compared with HCs. The vasodilator response to ACh was similar among patients with CAP (relative mean difference based on log values 13.3%; 95% CI −35.0 to 97.7%; P = 0.652) but was lower in the patients with diabetes with neuropathy (157.5%; 42.0–366.7%; P = 0.003) and without neuropathy (174.2%; 44.2–421.3%; P = 0.003) compared with HCs. No significant differences were found between the groups of patients with diabetes (P = 0.845). The vasodilator response to SNP was not significantly different among the groups (P = 0.082). CONCLUSIONS In this study, endothelium-dependent vasodilation was reduced in patients with type 2 diabetes regardless of the presence of polyneuropathy, whereas microvascular vasodilation was normal in patients with CAP. These data suggest that in type 2 diabetes, neuropathy does not contribute to impaired microvascular endothelium-dependent vasodilation and vice versa. In addition, this study suggests that impaired microvascular vasodilation does not contribute to CAP.

It has been demonstrated that insulin’s vascular actions contribute to regulation of insulin sensitivity. Insulin’s effects on muscle perfusion regulate postprandial delivery of nutrients and hormones to insulin-sensitive tissues. We here describe a technique for combining intravital microscopy (IVM) and contrast-enhanced ultrasonography (CEUS) of the adductor compartment of the mouse hindlimb to simultaneously visualize muscle resistance arteries and perfusion of the microcirculation in vivo. Simultaneously assessing insulin’s effect at multiple levels of the vascular tree is important to study relationships between insulin’s multiple vasoactive effects and muscle perfusion. Experiments in this study were performed in mice. First, the tail vein cannula is inserted for the infusion of anesthesia, vasoactive compounds and ultrasound contrast agent (lipid-encapsulated microbubbles). Second, a small incision is made in the groin area to expose the arterial tree of the adductor muscle compartment. The ultrasound probe is then positioned at the contralateral upper hindlimb to view the muscles in cross-section. To assess baseline parameters, the arterial diameter is assessed and microbubbles are subsequently infused at a constant rate to estimate muscle blood flow and microvascular blood volume (MBV). When applied before and during a hyperinsulinemic-euglycemic clamp, combined IVM and CEUS allow assessment of insulin-induced changes of arterial diameter, microvascular muscle perfusion and whole-body insulin sensitivity. Moreover, the temporal relationship between responses of the microcirculation and the resistance arteries to insulin can be quantified. It is also possible to follow-up the mice longitudinally in time, making it a valuable tool to study changes in vascular and whole-body insulin sensitivity.

BackgroundAnkylosing spondylitis (AS) is associated with an increased cardiovascular risk that might be due to the chronic underlying inflammatory process. We investigated whether subclinical atherosclerosis of the carotid artery in patients with AS was reduced after anti-inflammatory treatment with tumour necrosis factor (TNF) inhibitors in a prospective observational cohort study.Methods67 out of 81 AS patients who used TNF inhibitors and underwent ultrasonography at baseline returned for follow-up after 4.9 years. Of all patients, 12 (15%) discontinued the use of TNF inhibitors. Assessments of medication use, AS-related factors and cardiovascular risk factors were measured at baseline and repeated at follow-up. B-mode carotid ultrasonography was used to investigate arterial wall parameters, including carotid intima-media thickness (cIMT) and Young's elastic modulus (YEM).ResultsAfter a median 4.9 years of follow-up, cIMT did not change significantly (paired t test +0.011 mm, p=0.561) in those who continued the use of TNF inhibitors, while cIMT increased substantially (+0.057 mm, p=0.069) in those who did not continue their use of TNF inhibitors. The effect of TNF inhibitors was mainly mediated by a subsequent decrease in AS disease activity. Vascular elasticity (as measured with YEM) did not change significantly in patients who discontinued TNF inhibitors or those who continued TNF inhibitors.ConclusionsThe use of TNF inhibitors might stabilise or slow down the progression of subclinical atherosclerosis in AS patients, reflecting a decreased cardiovascular risk in these patients.

Objective The mechanisms underlying obesity-related hypertension are incompletely understood. Microvascular dysfunction might play a role by increasing peripheral vascular resistance (PVR). Metabolic and microvascular effects of insulin are impaired in obesity, but how these impairments contribute to disturbed blood pressure homeostasis is unclear. Specifically, it is unknown whether local microvascular vasoactive effects of insulin play a role in determining systemic vascular resistance. The aim of this study was to investigate the association between PVR and local microvascular effects of insulin. Design and Methods Thirty-seven healthy, overweight subjects (age 25-55 years, BMI 25-30 kg/m2) were cross-sectionally studied. Local insulin-mediated vasodilation was measured using skin laser Doppler fluxmetry combined with transcutaneous iontophoresis of insulin. For comparison, local vasodilatory effects of acetylcholine and sodium nitroprusside were measured. PVR was calculated from mean arterial pressure and cardiac output, assessed by pulse-dye densitometry. Results PVR was inversely correlated with insulin-mediated vasodilation (r = −0.50; P < 0.01). This finding was maintained after adjustment for age, sex, blood pressure, and smoking. PVR was not associated with local microvascular effects of acetylcholine. Conclusions Our study in overweight subjects suggests that insulin's role in the microvasculature may contribute to blood pressure control.

Chronic GVHD (cGVHD) complicating allo-SCT commonly presents as sclerotic skin changes resembling systemic sclerosis (SSc), suggesting a common pathophysiological pathway. Damage to capillaries is considered an early event in the pathogenesis of SSc, and is associated with characteristic nailfold capillary abnormalities. Whether such nailfold capillary abnormalities occur in sclerodermatous cGVHD is unknown. Nailfold videocapillaroscopy (NVC) was used to evaluate capillary morphology, density and loop dimensions in 14 patients with sclerodermatous cGVHD, 14 sex- and age-matched SSc patients, and 14 healthy controls. It was shown that none of the cGVHD patients and controls, whereas all SSc patients showed severe capillary abnormalities. cGVHD patients and controls showed no differences in capillary density (9.05 vs 9.16 loops/mm, respectively, P=0.84), and capillary loop dimensions (total loop width 44.36 vs 45.56 μm, respectively, P=0.84). Compared with cGVHD patients, SSc patients had a reduced capillary density (9.05 vs 5.25 loops/mm, respectively, P

BACKGROUND Recent experimental studies in adults have demonstrated that interruptions to prolonged sitting have beneficial effects on metabolic risk factors in adults, compared to prolonged sitting. We explored the hypothesis that multiple consecutive days of predominantly prolonged sedentary time may have an unfavorable effect on the postprandial response of C-peptide, glucose and triglycerides in free-living healthy young men. METHODS In this explorative pilot study, healthy young men (n=7; 18-23yrs) consumed standardized mixed meals at 1 and 5 hours during two experimental laboratory-sitting days, with six days of predominantly prolonged sedentary time in between. Serum and plasma samples were obtained hourly from 0 to 8 hours for measurement of glucose, C-peptide and triglycerides. Participant’s sedentary time was monitored using an accelerometer during the prolonged sedentary days as well as during six normal days prior to the first laboratory day. Differences in postprandial levels were assessed using generalized estimating equations analysis. Due to the explorative nature of this study and the small sample size, p-value was set at

A 53-year-old obese, but otherwise healthy, woman, participated in a study on impaired muscle perfusion in obesity. A muscle biopsy taken from this patient shows the fi rst identifi cation of perivascular adipose tissue (PVAT) in human muscle. In the past decade, evidence has accumulated that PVAT controls various vascular functions, including infl ammation, smooth-muscle tone, and endothelial function. Perivascular fat has been proposed to control insulin sensitivity through regulation of insulin-stimulated muscle perfusion. In 2015, PVAT was shown to determine insulin’s vasoactive eff ect on muscle arterioles; this regulation is impaired in obesity. The discovery of PVAT in human muscle and its vascular functions opens new avenues for the treatment of vascular disease and insulin resistance in obesity.

Objective— To assess the effects of glucagon-like peptide (GLP)-1–based therapies (ie, GLP-1 receptor agonists and dipeptidyl peptidase-4 inhibitors) on microvascular function in patients with type 2 diabetes mellitus. Approach and Results— We studied 57 patients with type 2 diabetes mellitus (mean±SD age: 62.8±6.9 years; body mass index: 31.8±4.1 kg/m 2 ; HbA 1c [glycated hemoglobin] 7.3±0.6%) in an acute and 12-week randomized, placebo-controlled, double-blind trial conducted at the Diabetes Center of the VU University Medical Center. In the acute study, the GLP-1 receptor agonist exenatide (therapeutic concentrations) or placebo (saline 0.9%) was administered intravenously. During the 12-week study, patients received the GLP-1 receptor agonist liraglutide (1.8 mg daily), the dipeptidyl peptidase-4 inhibitor sitagliptin (100 mg daily), or matching placebos. Capillary perfusion was assessed by nailfold skin capillary videomicroscopy and vasomotion by laser Doppler fluxmetry, in the fasting state and after a high-fat mixed meal. In neither study, treatment affected fasting or postprandial capillary perfusion compared with placebo ( P >0.05). In the fasting state, acute exenatide infusion increased neurogenic vasomotion domain power, while reducing myogenic domain power (both P P Conclusions— Despite modest changes in vasomotion, suggestive of sympathetic nervous system activation and improved endothelial function, acute exenatide infusion does not affect skin capillary perfusion in type 2 diabetes mellitus. Twelve-week treatment with liraglutide or sitagliptin has no effect on capillary perfusion or vasomotion in these patients. Our data suggest that the effects of GLP-1–based therapies on glucose are not mediated through microvascular responses.

Introduction Diabetes and pre-diabetes are highly prevalent in patients with a history of acute coronary syndrome. This is why screening for glucose metabolism disorders is recommended in patients following an acute coronary syndrome. The aim of our study was to determine whether glycated haemoglobin alone compared with the oral glucose tolerance test could allow effective screening for glucose metabolism disorders in acute coronary syndrome patients undergoing cardiac rehabilitation. Patients and methods Among 347 patients with a recent history of acute coronary syndrome enrolled in our cardiac rehabilitation centre, 267 patients without previously known diabetes were recruited for this prospective study with performance of both oral glucose tolerance test and glycated haemoglobin measurement. The patients were divided into three groups: newly diagnosed diabetes mellitus, pre-diabetes and normoglycaemia according to the oral glucose tolerance test and glycated haemoglobin results. The results obtained with glycated haemoglobin were compared with those obtained with the oral glucose tolerance test, considered as the reference. Results For the diagnosis of diabetes, glycated haemoglobin had a sensitivity of 72% and a specificity of 100%. Positive and negative predictive values were high at 100% and 96%, respectively. However, for the diagnosis of pre-diabetes the sensitivity of glycated haemoglobin was low at 64% as were the specificity (53%) and the positive predictive values (37%). Glycated haemoglobin overdiagnosed pre-diabetes (52% vs 30%, p 0.0001). For the diagnosis of normoglycaemia, the sensitivity of glycated haemoglobin was also low (48%). Conclusion According to our study, glycated haemoglobin has low sensitivity and specificity for the detection of pre-diabetes in patients with coronary disease enrolled in cardiac rehabilitation, and glycated haemoglobin over-diagnoses pre-diabetes in comparison with the oral glucose tolerance test.

Objective. To investigate the inter- and intra-observer reliability of both qualitative and quantitative parameters used in the assessment of nail-fold capillaroscopy images.Methods. Fifty mosaic nail-fold images of healthy controls (n = 10), patients with primary RP (n = 10) and SSc (n = 30) were assessed in random order by two blinded observers on two occasions at centres in Sweden, UK and The Netherlands. Each image was therefore scored by six observers twice.Results. Inter- and intra-observer reliability of quantitative parameters showed substantial to almost perfect agreement [inter- and intra-observer weighted κ's for the number of widened capillaries was 0.75 and 0.87 and giant capillaries was 0.84 and 0.92, intra-class correlation coefficients (ICCs) for capillary density was 0.87 and 0.92 and total loop width was 0.94 and 0.98, respectively]. Qualitative parameters including architecture, avascularity, haemorrhage, crossed, ramified and bushy capillaries showed moderate to substantial inter-observer reproducibility (weighted κ ranging from 0.47 to 0.73), and substantial intra-observer repeatability (weighted κ ranging from 0.71 to 0.80), whereas the scoring of tortuous and bizarre capillaries showed poor inter-observer and substantial intra-observer agreement (inter-observer weighted κ's was 0.39 and 0.21 and intra-observer weighted κ's was 0.68 and 0.76, respectively).Conclusion. All quantitative and certain qualitative parameters are highly reliable in terms of inter- and intra-observer agreement. A combination of parameters with the highest reliability should be incorporated into future capillaroscopic scoring systems in studies of prediction and monitoring of SSc spectrum disorders. (Less)

SummaryCurrent strategies combining anti-angiogenic drugs with chemotherapy provide clinical benefit in cancer patients. It is assumed that anti-angiogenic drugs, such as bevacizumab, transiently normalize abnormal tumor vasculature and contribute to improved delivery of subsequent chemotherapy. To investigate this concept, a study was performed in non-small cell lung cancer (NSCLC) patients using positron emission tomography (PET) and radiolabeled docetaxel ([11C]docetaxel). In NSCLC, bevacizumab reduced both perfusion and net influx rate of [11C]docetaxel within 5 hr. These effects persisted after 4 days. The clinical relevance of these findings is notable, as there was no evidence for a substantial improvement in drug delivery to tumors. These findings highlight the importance of drug scheduling and advocate further studies to optimize scheduling of anti-angiogenic drugs.

Please cite this paper as: de Boer, Meijer, Wijnstok, Jonk, Houben, Stehouwer, Smulders, Eringa and Serne (2012). Microvascular Dysfunction: A Potential Mechanism in the Pathogenesis of Obesity-associated Insulin Resistance and Hypertension. Microcirculation 19(1), 5–18. Abstract The intertwined epidemics of obesity and related disorders such as hypertension, insulin resistance, type 2 diabetes, and subsequent cardiovascular disease pose a major public health challenge. To meet this challenge, we must understand the interplay between adipose tissue and the vasculature. Microvascular dysfunction is important not only in the development of obesity-related target-organ damage but also in the development of cardiovascular risk factors such as hypertension and insulin resistance. The present review examines the role of microvascular dysfunction as an explanation for the associations among obesity, hypertension, and impaired insulin-mediated glucose disposal. We also discuss communicative pathways from adipose tissue to the microcirculation.

Obesity is associated with insulin resistance, hypertension, and cardiovascular disease, but the mechanisms underlying these associations are incompletely understood. Microvascular dysfunction may play an important role in the pathogenesis of both insulin resistance and hypertension in obesity. Adipose tissue-derived substances (adipokines) and especially inflammatory products of adipose tissue control insulin sensitivity and vascular function. In the past years, adipose tissue associated with the vasculature, or perivascular adipose tissue (PAT), has been shown to produce a variety of adipokines that contribute to regulation of vascular tone and local inflammation. This review describes our current understanding of the mechanisms linking perivascular adipose tissue to vascular function, inflammation, and insulin resistance. Furthermore, we will discuss mechanisms controlling the quantity and adipokines secretion by PAT.

BACKGROUND: Central fatness is associated with higher arterial stiffness, a mechanism that may explain adiposity-related increases in cardiovascular disease risk. In contrast, peripheral fat and lean masses may counteract such adverse effects, but evidence of this contention, as derived from longitudinal studies at the general population level, is lacking. OBJECTIVE: The objective was to investigate the associations between changes in central (ie, trunk) fat mass, peripheral (ie, limbs) fat mass, and lean masses with changes in arterial stiffness. DESIGN: A longitudinal study in 277 (145 women) healthy adults was conducted. Body composition (dual-energy X-ray absorptiometry) and arterial stiffness estimates (ultrasound imaging) were measured repeatedly at the ages of 36 and 42 y. RESULTS: Changes (per 10 kg) in trunk fat mass were positively associated and changes in peripheral fat mass were inversely associated with carotid Young's elastic modulus (in 10(3) . kPa) [beta = 0.14 (95% CI: 0.02, 0.25) and -0.16 (-0.30, -0.01), respectively] and carotid-femoral pulse wave velocity (in m/s) [beta = 1.54 (0.02, 3.07) and -1.46 (-3.48, 0.56), respectively]. Individuals in whom trunk fat increased and peripheral fat decreased over the 6-y follow-up (33% of the study population) had the steepest increases in these stiffness estimates. Notably, these changes were accompanied by minor increases in body weight, which remained within the limits of the normal range throughout. CONCLUSIONS: Increases in trunk mass and decreases in peripheral fat mass are associated with accelerated arterial stiffening. These findings emphasize the importance of assessing regional changes in body composition, because it may enable identification of individuals with an unrecognized increased cardiovascular disease risk.

ObjectiveBased on fasting insulin and glucose, several indices of insulin sensitivity have been developed in adults. Recently, it has been demonstrated that incorporation of the fasting free fatty acid (FFA) concentration improves the association with insulin sensitivity in adults. We investigated the association of clamp-derived insulin sensitivity with indices of insulin sensitivity derived from fasting blood in prepubertal children and adults, with and without incorporation of FFAs.Design and methodsWe studied 59 healthy adults and 29 of them are prepubertal children. We measured insulin sensitivity with the euglycemic–hyperinsulinemic clamp. Based on fasting insulin and glucose, we estimated insulin sensitivity with the homeostasis model assessment (HOMA), the quantitative insulin sensitivity check index (QUICKI), and the revised QUICKI after the incorporation of FFAs.ResultsThe associations of HOMA and QUICKI with clamp-derived insulin sensitivity in children (r=−0.55 and 0.54 respectively;Pr=−0.54 and 0.53 respectively;Pr=0.68 and 0.48 respectively;PPvalue 0.004 in adults and 0.3 in children).ConclusionsHOMA and QUICKI are associated with clamp-derived insulin sensitivity in both children and adults. Incorporating fasting levels of FFAs into the QUICKI model improves the association with clamp-derived insulin sensitivity in adults, but not in children.

The association between birth weight and blood pressure is well established but at present unexplained. According to the Borst-Guyton concept, chronic hypertension can occur only with a shift in the renal pressure–natriuresis relationship resulting in increased salt sensitivity of blood pressure. We assessed salt sensitivity of blood pressure in a group of 27 healthy adults whose birth weight was available. Birth weight was ascertained from birth certificates or announcements. Salt sensitivity of blood pressure was determined as difference in mean arterial pressure (MAP) between a 1-week high-salt (≈235 mmol NaCl/d) versus low-salt diet (≈55 mmol NaCl/d). Creatinine clearance was estimated according to the formula of Cockcroft and Gault. Birth weight was negatively associated with salt sensitivity of blood pressure ( r =−0.60, P =0.002). The creatinine clearance was positively associated with birth weight ( r =0.53; P =0.008) but did not influence the association between birth weight and salt sensitivity of blood pressure. Birth weight is associated with salt sensitivity of blood pressure, and this may play a role in the maintenance of elevated blood pressure in individuals with a low birth weight.

A high proportion of women with the polycystic ovary syndrome (PCOS) are obese. It is unclear whether normal-weight women with PCOS are at a greater risk of diabetes and cardiovascular disease than obese women without PCOS. It is also unclear whether risks of diabetes and cardiovascular disease in obese women and those with PCOS are additive. To determine whether the risk of diabetes and cardiovascular disease in PCOS is independent of the risk associated with obesity, this prospective controlled study compared insulin sensitivity and microvascular function in normal-weight and obese women with and without PCOS. The 4 PCOS groups were comprised of 19 normal-weight and 16 obese women with PCOS, and 14 normal-weight and 13 obese women controls without PCOS matched for age and body mass index. Before and after insulin infusion to produce hyperinsulinemia, metabolic insulin sensitivity (M/I value) was measured by means of the isoglycemic hyperinsulinemic clamp, and microvascular insulin sensitivity was assessed by analysis of microvascular endothelium-dependent and independent vasodilatation using iontophoresis of acetylcholine (Ach) and sodium nitroprusside (SNP) in combination with laser Doppler flowometry in the skin. For the latter, area under the response curves to Ach and SNP were measured. Analysis of metabolic insulin sensitivity showed that both groups of obese women had a significantly lower M/I value than normal-weight women (P ≤ 0.001) and that obese PCOS women had a lower M/I value than obese controls (P ≤ 0.02). In contrast, there was no difference in the M/I value between normal-weight PCOS women and controls. Before insulin infusion, there was no significant difference in microvascular responses to Ach among the 4 groups. During insulin infusion, Ach responses were significantly reduced in obese compared with normal-weight women; a similar difference was found for normal-weight women with or without PCOS. Compared to baseline values, SNP-dependent vasodilatation was not increased during insulin infusion in the 4 groups (P = ns). This report is the first to show that normal-weight women with PCOS may be at relatively normal risk of metabolic and cardiovascular disease and that obese woman with PCOS may be at increased risk. The investigators conclude from these findings that the focus of management in women with PCOS should be on weight control.

Obesity is an important risk factor for insulin resistance and hypertension and plays a central role in the metabolic syndrome. Insight into the pathophysiology of this syndrome may lead to new treatments. This paper has reviewed the evidence for an important role for the microcirculation as a possible link between obesity, insulin resistance and hypertension.