Search

Objectives: The aim of this study was to use the parametric g-formula to estimate the 19-year risk of myocardial infarction (MI) under hypothetical interventions on six cardiovascular risk factors., Design and Setting: A populations-based cohort study with repeated measurements, the Tromsø Study., Primary Outcome Measure: Myocardial infarction., Participants: We estimated the relative and absolute risk reduction under feasible and intensive risk reduction strategies for smoking, physical activity, alcohol drinking, body mass index, total serum cholesterol and systolic blood pressure in 14 965 men and women with 19 years of follow-up (1994-2013)., Results: The estimated 19-year risk of MI under no intervention was 7.5% in individuals with baseline mean age 49.3 years (range 25-69). This risk was reduced by 30% (95% CI 19% to 39%) under joint feasible interventions on all risk factors, and 70% (60%, 78%) under a set of more intensive interventions. The most effective interventions were lowering of total cholesterol to 5.18 mmol/L and lowering of systolic blood pressure to 120 mm Hg (33% and 37% lower MI risk, respectively). The absolute risk reductions were significantly larger in men, in older participants, in smokers and in those with low education., Conclusion: Modification of population levels of cardiovascular risk factors could have prevented close to one-third of the cases of MI in the municipality of Tromsø during 19 years of follow-up., Competing Interests: Competing interests: None declared., (© Author(s) (or their employer(s)) 2020. Re-use permitted under CC BY-NC. No commercial re-use. See rights and permissions. Published by BMJ.)

Background and Aims: Overall, men have roughly twice the risk of myocardial infarction (MI) compared to women, but what causes this contrast is unclear. Identification of subgroups where the gender contrast in risk is particularly low or high, may provide new insight. In the search for such subgroups, we focus on gender-specific effects of established coronary heart disease (CHD) risk factors. Heterogeneity across age groups is also explored., Methods: Population-based prospective study from Tromsø, Norway, comprising 33,859 individuals (51% women); 2746 individuals (854 women) received a diagnosis of MI during follow-up at ages 35-94 years. Incidence rate ratios (IRR) were calculated as estimates of relative risk in Poisson regression analyses., Results: The association between total cholesterol and risk of MI was stronger for men than women, and IRR for men vs. women accordingly increased with increasing cholesterol, but the risk was higher for men in all subgroups (IRR in range 1.63-3.27), except among older people with low cholesterol levels. The adverse effect of increasing blood pressure (BP) was stronger for women, and IRR for gender diminished with increasing systolic (from 3.90 to 1.38) and diastolic BP (from 2.87 to 1.54). The gender contrast in risk was also substantially reduced in smokers ≥75 years. Associations with high-density lipoprotein cholesterol (HDL-C) did not differ between genders., Conclusions: Gender heterogeneity in associations with total cholesterol but not HDL-C indicates gender differences in associations with non-HDL-C. The stronger association with BP in women may relate to more severe hypertension-induced left ventricular hypertrophy., (Copyright © 2017 Elsevier B.V. All rights reserved.)

To dissect the genetic architecture of blood pressure and assess effects on target organ damage, we analyzed 128,272 SNPs from targeted and genome-wide arrays in 201,529 individuals of European ancestry, and genotypes from an additional 140,886 individuals were used for validation. We identified 66 blood pressure-associated loci, of which 17 were new; 15 harbored multiple distinct association signals. The 66 index SNPs were enriched for cis-regulatory elements, particularly in vascular endothelial cells, consistent with a primary role in blood pressure control through modulation of vascular tone across multiple tissues. The 66 index SNPs combined in a risk score showed comparable effects in 64,421 individuals of non-European descent. The 66-SNP blood pressure risk score was significantly associated with target organ damage in multiple tissues but with minor effects in the kidney. Our findings expand current knowledge of blood pressure-related pathways and highlight tissues beyond the classical renal system in blood pressure regulation.

High blood pressure is a modifiable risk factor for cardiovascular disease. Previous studies showing a blood pressure decline in recent decades lack data to follow individuals born in different decades from early and middle adulthood to older age. We investigated changes in age-specific blood pressure by repeated measurements in 37973 women and men born 1905 to 1977 (aged 20-89 years) examined ≤5× between 1979 and 2008 in the population-based Tromsø Study. Mixed models were used to estimate time trends. Mean systolic and diastolic blood pressure decreased from 1979 to 2008 in both genders in the age groups 30 to 89 years. The decrease was similar in the 80th percentile and the 20th percentile of the population blood pressure distribution. The decrease in systolic blood pressure in age group 40 to 49 years was 10.6 mm Hg in women and 4.5 mm Hg in men. Systolic blood pressure increased with age in women and men born 1920 to 1949, whereas a decrease or flattening of curve was observed in the younger birth cohorts. Thus, we found both time periodic and cohort effects, and trends were more pronounced in women than in men. The findings suggest changes in blood pressure in the population rather than an effect of treatment of high-risk individuals., (© 2015 American Heart Association, Inc.)

Objectives: Hypertension is both a cause and a consequence of kidney disease. Whether there is an association between the earliest stages of elevated blood pressure and variations in kidney function within the normal range in the general population has not been investigated using accurate methodology., Methods: Glomerular filtration rate (GFR) by iohexol clearance and 24-h blood pressure were measured in a cross-sectional sample (n = 1627) from the general population aged from 50 to 62 years. None of the participants had known cardiovascular disease, chronic kidney disease, or diabetes., Results: In multiple linear regression analyses with multivariate adjustment, GFR was associated with both ambulatory SBP and DBP and their interaction in separate models for daytime and night-time (P < 0.05). For blood pressure in the normotensive range, GFR increased with higher daytime SBP and with night-time SBP and DBP. In the daytime, higher DBP was associated with a slight decrease in GFR., Conclusion: GFR was associated with blood pressure in both the normotensive and hypertensive range. Although no conclusion about causality can be drawn from these cross-sectional relationships, they are consistent with the hypotheses of a causal relationship between renal function and blood pressure at a very early stage of hypertension or renal impairment.

Aims To study change over 8 years in cardiovascular risk, achievement of national guideline-based treatment targets of lipids, blood pressure (BP) and smoking in primary prevention of cardiovascular disease (CVD), medication use, and characteristics associated with target achievement among individuals with high CVD risk in a general population. Methods and results We followed 2524 women and men aged 40-79 years with high risk of CVD attending the population-based Troms0 study in 2007-08 (Troms06) to their participation in the next survey in 2015-16 (Troms07). We used descriptive statistics and regression models to study change in CVD risk and medication use, and characteristics associated with treatment target achievement. In total, 71.4% reported use of BP- and/or lipid-lowering medication at second screening. Overall, CVD risk decreased during follow-up, with a larger decrease among medication users compared with non-users. Treatment target achievement was 31.0% for total cholesterol <5 mmol/L, 27.3% for LDL cholesterol <3 mmol/L, 43.4% for BP <140/90 (<135/85 if diabetes) mmHg, and 85.4% for non-smoking. A total of 9.8% reached all treatment targets combined. Baseline risk factor levels and current medication use had the strongest associations with treatment target achievement. Conclusion We found an overall improvement in CVD risk factors among high-risk individuals over 8 years. However, guideline-based treatment target achievement was relatively low for all risk factors except smoking. Medication use was the strongest characteristic associated with achieving treatment targets. This study has demonstrated that primary prevention of CVD continues to remain a major challenge. [ABSTRACT FROM AUTHOR]

Aims: To examine the associations between diastolic dysfunction indices and long‐term risk of all‐cause mortality in adults over 23‐year follow‐up. Methods and results: Participants (n = 2734) of the population‐based Tromsø Study of Norway had echocardiography in 1994–1995. Of these 67% were repeated in 2001 and/or 2007–2008. Mortality between 1994 and 2016 was determined by linkage to the national death registry. Cox regression was used to model the hazard of all‐cause mortality in relation to left atrial parameters (treated as time‐dependent using repeated measurements) adjusted for traditional risk factors and cardiovascular disease. During the follow‐up, 1399 participants died. Indexed left atrial diameter, mitral peak E deceleration time, and mitral peak E to peak A ratio showed an U‐shaped association with all‐cause mortality. Combining left atrial diameter with mitral peak E deceleration time increased the prognostic accuracy for all‐cause mortality whereas adding mitral peak E to peak A ratio did not increase prognostic value. We estimated new optimal cutoff values of left atrial diameter, mitral peak E deceleration time, and mitral peak E to peak A ratio for all‐cause mortality outcome. E/e′ had a cubic relation to mortality. Conclusion: Both enlarged and small left atrial diameters were associated with increased all‐cause mortality risk. A combination of Doppler‐based left ventricle filling parameters had an incremental effect on all‐cause mortality risk. The cutoff values of diastolic dysfunction indices we determined had similar all‐cause mortality prediction ability as those recommended by American Association of Echocardiography and European Association of Cardiovascular Imaging. [ABSTRACT FROM AUTHOR]

Background Studies on the relationship between temporal trends in risk factors and incidence rates of intracerebral hemorrhage are scarce. Aims To analyze temporal trends in risk factors and incidence rates of intracerebral hemorrhage using individual data from a population-based study. Methods We included 28,167 participants of the Tromsø Study enrolled between 1994 and 2008. First-ever intracerebral hemorrhages were registered through 31 December 2013. Hazard ratios (HRs) for intracerebral hemorrhage were analyzed by Cox proportional hazards models, risk factor levels over time by generalized estimating equations, and incidence rate ratios (IRR) by Poisson regression. Results We registered 219 intracerebral hemorrhages. Age, male sex, systolic blood pressure (BP), diastolic BP, and hypertension were associated with intracerebral hemorrhage. Hypertension was more strongly associated with non-lobar intracerebral hemorrhage (HR 5.08, 95% CI 2.86–9.01) than lobar intracerebral hemorrhage (HR 1.91, 95% CI 1.12–3.25). In women, incidence decreased significantly (IRR 0.46, 95% CI 0.23–0.90), driven by a decrease in non-lobar intracerebral hemorrhage. Incidence rates in men remained stable (IRR 1.27, 95% CI 0.69–2.31). BP levels were lower and decreased more steeply in women than in men. The majority with hypertension were untreated, and a high proportion of those treated did not reach treatment goals. Conclusions We observed a significant decrease in intracerebral hemorrhage incidence in women, but not in men. A steeper BP decrease in women may have contributed to the diverging trends. The high proportion of untreated and sub-optimally treated hypertension calls for improved strategies for prevention of intracerebral hemorrhage. [ABSTRACT FROM AUTHOR]

Background: Vitamin D deficiency may be a risk factor for mortality but previous meta-analyses lacked standardization of laboratory methods for 25-hydroxyvitamin D (25[OH]D) concentrations and used aggregate data instead of individual participant data (IPD). We therefore performed an IPD meta-analysis on the association between standardized serum 25(OH)D and mortality. Methods: In a European consortium of eight prospective studies, including seven general population cohorts, we used the Vitamin D Standardization Program (VDSP) protocols to standardize 25(OH)D data. Meta-analyses using a one step procedure on IPD were performed to study associations of 25(OH)D with all-cause mortality as the primary outcome, and with cardiovascular and cancer mortality as secondary outcomes. This meta-analysis is registered at ClinicalTrials.gov, number NCT02438488. Findings: We analysed 26916 study participants (median age 61.6 years, 58% females) with a median 25(OH)D concentration of 53.8 nmol/L. During a median follow-up time of 10.5 years, 6802 persons died. Compared to participants with 25(OH)D concentrations of 75 to 99.99 nmol/L, the adjusted hazard ratios (with 95% confidence interval) for mortality in the 25(OH)D groups with 40 to 49.99, 30 to 39.99, and <30 nmol/L were 1.15 (1.00–1.29), 1.33 (1.16–1.51), and 1.67 (1.44–1.89), respectively. We observed similar results for cardiovascular mortality, but there was no significant linear association between 25(OH)D and cancer mortality. There was also no significantly increased mortality risk at high 25(OH)D levels up to 125 nmol/L. Interpretation: In the first IPD meta-analysis using standardized measurements of 25(OH)D we observed an association between low 25(OH)D and increased risk of all-cause mortality. It is of public health interest to evaluate whether treatment of vitamin D deficiency prevents premature deaths. [ABSTRACT FROM AUTHOR]

Background: Single measurements of modifiable risk factors may underestimate associations with outcomes in cohorts. We aimed to compare risk estimates of myocardial infarction (MI) and venous thromboembolism (VTE) by atherosclerotic risk factors during long follow-up using time-fixed analyses without and with correction for regression dilution and time-varying analyses. Methods: The study included 5970 subjects enrolled in the fourth survey of the Tromsø Study (1994/95). Blood pressure, lipid levels, body mass index (BMI), diabetes and smoking status were measured at baseline, and subjects still alive at the fifth (2001/02, n = 5179) and sixth (2007/08, n = 4391) survey were re-measured. Incident events of MI (n = 714) and VTE (n = 214) were recorded until December 2010. Time-fixed and time-varying Cox regression models were used to estimate hazard ratios (HR) for MI and VTE adjusted for age and sex. Results: Variations in BMI, blood pressure and lipid levels were small, and did not alter the risk estimates when time-varying analyses were compared to time-fixed analyses. For MI, variables that changed considerably over time yielded the greatest changes in risk estimates (HR for smoking changed from 1.80 (95% CI 1.55–2.10) to 2.08 (95% CI 1.78–2.42)). For VTE, only BMI was associated with increased risk in both time-fixed and time-varying analysis, but the risk estimates weakened in the time-varying analysis. Correction of time-fixed HRs with Rosner´s method tended to overestimate risk estimates compared to time-varying analysis. Comment: For MI and VTE, risk estimates based on baseline and repeated measures corresponded well, whereas correction for regression dilution tended to overestimate risks. [ABSTRACT FROM AUTHOR]

. Purpose: To determine the prevalence and risk factors for retinopathy in a nondiabetic population. Methods: The study population included 5869 participants without diabetes aged 38-87 years from the Tromsø Eye Study, a substudy of the population-based Tromsø Study in Norway. Retinal images from both eyes were graded for retinopathy. We collected data on risk factors from self-report questionnaires, clinical examinations, laboratory measurements and case note reviews. The cross-sectional relationship between potential risk factors and retinopathy was assessed using logistic regression analysis. Results: The overall prevalence of retinopathy was 14.8%. Men had a higher prevalence of retinopathy compared with women (15.9% versus 14.0%, p = 0.04). In men, retinopathy was associated with hypertension (odds ratio [OR], 1.59; 95% confidence interval [CI], 1.24-2.04) and HbA1c (OR per %, 1.41; 95% CI, 1.01-1.96). In women, retinopathy was associated with age (OR per 10 years, 1.32; 95% CI, 1.14-1.52), log-transformed urinary albumin excretion (OR per log unit, 1.46; 95% CI, 1.14-1.87) and hypertension (OR, 1.36; 95% CI, 1.08-1.71). In women, retinopathy was associated with very low levels of urinary albumin excretion (urinary albumin/creatinine ratio >0.43 mg/mmol). Conclusion: This study confirms results from previous studies on the strong association between blood pressure and retinopathy. A novel finding is the sex differences in risk factors for retinopathy, suggesting a sex difference in the pathogenesis leading to retinopathy. [ABSTRACT FROM AUTHOR]

Tracking of cardiovascular risk factors (blood pressure, body mass index (BMI), and serum lipids) has not been studied much in a general, adult population. No known study has compared tracking of these factors for both sexes. In the present study, 17,710 men and women aged 20-61 years at baseline attended two or three population-based health surveys in Tromsø, Norway, over 16 years (between 1979-1980 and 1994-1995). Tracking coefficients were estimated by using different methods, and possible predictors of tracking were found. There was a high degree of tracking for BMI (overall tracking coefficients: 0.85 for men, 0.80 for women). Relatively high (or moderate) tracking was found for systolic blood pressure (respective sex-specific coefficients: 0.52, 0.54), diastolic blood pressure (0.48, 0.48), high density lipoprotein cholesterol (0.55, 0.64), and total cholesterol (0.77, 0.65). The lowest coefficients were for triglycerides (0.43, 0.39). Analysis of tracking in the upper sextile confirmed these results. Although some baseline predictors were associated with tracking, the effects were relatively weak. When predictors for tracking in the upper sextile were assessed, significant associations were found with relatively strong effects. No major sex differences were observed in tracking. However, women were more likely than men to remain in the upper sextile of systolic and diastolic blood pressures and of BMI. [ABSTRACT FROM AUTHOR]

The aim of this study was to explore sex-specific associations between systolic blood pressure (SBP), hypertension, and the risk of incident atrial fibrillation (AF) subtypes, including paroxysmal, persistent, and permanent AF, in a general population. A total of 13,137 women and 11,667 men who participated in the fourth survey of the Tromsø Study (1994–1995) were followed up for incident AF until the end of 2016. Cox proportional hazards regression analysis was conducted using fractional polynomials for SBP to provide sex- and AF-subtype-specific hazard ratios (HRs) for SBP. An SBP of 120 mmHg was used as the reference. Models were adjusted for other cardiovascular risk factors. Over a mean follow-up of 17.6 ± 6.6 years, incident AF occurred in 914 (7.0%) women (501 with paroxysmal/persistent AF and 413 with permanent AF) and 1104 (9.5%) men (606 with paroxysmal/persistent AF and 498 with permanent AF). In women, an SBP of 180 mmHg was associated with an HR of 2.10 (95% confidence interval [CI] 1.60–2.76) for paroxysmal/persistent AF and an HR of 1.80 (95% CI 1.33–2.44) for permanent AF. In men, an SBP of 180 mmHg was associated with an HR of 1.90 (95% CI 1.46–2.46) for paroxysmal/persistent AF, while there was no association with the risk of permanent AF. In conclusion, increasing SBP was associated with an increased risk of both paroxysmal/persistent AF and permanent AF in women, but only paroxysmal/persistent AF in men. Our findings highlight the importance of sex-specific risk stratification and optimizing blood pressure management for the prevention of AF subtypes in clinical practice. [ABSTRACT FROM AUTHOR]

In a large longitudinal study, we examined the relationships between cardiovascular risk factors (blood lipids, blood pressure, smoking, and physical activity), and change in these risk factors over a 7-year period, and the risk of clinical diabetes mellitus type 2. There were 73 verified new cases of clinical diabetes mellitus type 2 (diagnosed between 1987 and 1995) and 9,982 controls who consistently denied diabetes in three health surveys in 1979/1980, 1986/1987, and 1994/1995. Baseline body mass index, serum triglycerides, high-density lipoprotein (HDL) cholesterol, blood pressure, and physical activity in leisure, as well as change in these risk factors, were significant predictors for clinical diabetes mellitus type 2. Thus, both the level of risk factors at baseline and change in risk factor level are of importance for the risk of clinical diabetes mellitus type 2. [Copyright &y& Elsevier]