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Continuous positive airway pressure treatment has been shown to lower blood pressure (BP) in patients with obstructive sleep apnea (OSA). The aims of the present pilot study were to evaluate the potential effects of oral appliance (OA) therapy on BP, to assess various outcome BP measures, and to inform sample size calculation.Seventy-two patients with OSA and hypertension were randomly assigned to intervention with either an OA with mandibular advancement (active group) or an OA without advancement (control group). Before and after 3 months of treatment, the patients underwent nocturnal somnographic registration and 24-h ambulatory BP monitoring.Among the various BP measures, the largest trend toward effect of OA treatment was seen in 24-h mean systolic BP with a 1.8 mmHg stronger BP reduction in the active group compared with controls. A stronger trend toward effect was seen in a subgroup with baseline ambulatory daytime mean systolic BP135/85 mmHg where the mean systolic BP fell, on average, 2.6 mmHg. Additional exclusion of patients with baseline apnea hypopnea index (AHI) ≤15 gave a significant reduction in mean systolic BP of 4.4 mmHg (P = 0.044) in the active group compared with controls.In patients with OSA and hypertension, OA treatment had a modest trend toward effect on reducing BP. A stronger trend toward treatment effect was seen after excluding patients with normal baseline ambulatory BP. Additional exclusion of patients with baseline AHI ≤15 showed a significant treatment effect. Data to inform sample size for an adequately powered randomized study are provided.

Leisure-time physical inactivity and risk of myocardial infarction and all-cause mortality : A case-control study

Objective: Studies on the prognostic importance of the systolic blood pressure (SBP) response during exercise report ambiguous results. Most research focuses on younger and middle-aged selected patient groups and rarely includes women. We investigated the prognostic value of SBP response during exercise testing in 75-year-olds. Design: Prospective observational cohort study. Setting: A community-based random sample of 75-year-old men and women (n = 382). Main outcome measures: The prognostic value of SBP change from rest to peak exercise during a symptom-limited cycle test was evaluated for the endpoints all-cause mortality and cardiovascular mortality during long-term follow-up. Results: After a median follow-up of 10.6 years, 140 (37%) of the participants had died, 64 (17%) from cardiovascular causes. The all-cause mortalities for exercise SBP changes of ⩽30 mm Hg, 31–55 mm Hg and >55 mm Hg were 5.1, 4.2 and 2.6 per 100 person-years, respectively (logrank 9.6; p = 0.008). For every 10 mm Hg increase in SBP during exercise the relative hazard for all-cause mortality was reduced by 13% (p = 0.030) and for cardiovascular mortality by 26% (p = 0.004) after adjustment for sex, smoking, waist circumference, total/HDL cholesterol ratio, prevalent ischaemic heart disease, hypertension, diabetes, cardiovascular medication, pre-exercise SBP, exercise capacity, resting left ventricular ejection fraction and left ventricular mass index. Conclusions: Our findings suggest that an augmented SBP response during exercise is associated with an improved long-term survival among community-living 75-year-old individuals.

Factor analysis reduces a set of directly measured variables into a smaller set of underlying factors representing unique statistically independent domains termed "factors." In middle-aged people, previous factor analyses of the components of the metabolic syndrome have identified two to four factors. Many of these analyses report blood pressure as one of these factors.We performed a factor analysis of the individual continuous components of the metabolic syndrome among 198 men and 203 women comprising 65% of all 75 year olds from the city of Västerås in Sweden.The metabolic syndrome comprised two factors. Factor 1, the metabolic factor, consisted of waist circumference, high-density lipoprotein cholesterol, triglycerides, and fasting glucose, whereas factor 2, the blood pressure factor, consisted of systolic and diastolic blood pressure. These two factors explained 58% (factor 1, 31%, and factor 2, 27%) of the total variation in men. The corresponding figures for women were 63% (factor 1, 36%, and factor 2, 27%). Factor 1 was significantly related to a decreased 10 years of survival for men, with a hazard ratio (HR) of 1.30 (95% confidence interval [CI] 1.07-1.58, P = 0.008), and nearly significantly for women, with a HR of 1.27 (95% CI 0.98-1.64, P = 0.071). In a pooled analysis adjusting for sex, known cardiovascular disease, and hypertension, high blood pressure, and current smoking, the HR for factor 1 was 1.20 (95% CI 1.02-1.49, P = 0.026). Factor 2 was not significantly related to survival.Factor analysis of the basic variables of the metabolic syndrome among 75 year olds from a general population identified a metabolic factor and a blood pressure factor. The former factor was significantly related to 10-year survival and the relationship remained after adjusting for known cardiovascular disease and hypertension and current smoking.

A positive relation between the metabolic syndrome (MetS) and inflammatory activity has been reported. The purpose of this investigation was to study the relationships between 1) white blood cell (WBC) count and MetS, 2) WBC count and the individual components of MetS and 3) WBC count and insulin sensitivity in 75-year-old women and men from the general population.The study included 200 women and 196 men comprising 64% of the 75-year old people from the city of Västerås in Sweden. MetS was defined according to the National Cholesterol Education Program (NCEP).WBC count (10(9)/L; median and interquartile range) was 5.7 (4.9-6.8) for women and 6.3 (5.4-7.2) for men, P.001 for gender difference. For women with and without MetS, WBC count was 6.3 (5.3-7.3) and 5.4(4.7-6.3), respectively. For men the corresponding figures were 6.7 (5.9-7.6) and 6.1 (5.4-7.1).The difference in WBC count between individuals with and without MetS was significant (P.001 for women; P = .014 for men). All individual components of MetS (with exception of blood pressure) were more strongly associated with WBC count for women than for men. Insulin sensitivity, measured as HOMA-IR (HOmeostasis Model Assessment-Insulin Resistance) index, was significantly associated with WBC count in women but not in men.In this elderly population, individuals with MetS had a higher WBC count than those without. Women had a lower WBC count and stronger relationship between WBC count and insulin sensitivity than did men.

The increase in left ventricular (LV) end-diastolic volume has recently been shown to explain more than 70% of the increase in stroke volume during upright exercise in endurance athletes. As the end-diastolic volume enhancement not could be explained by an increase in axial cavity length an augmentation in LV short-axis diameters is to be expected. To investigate LV end-diastolic geometrical alterations during exercise, 15 endurance athletes were examined using contrast exercise echocardiography. LV end-diastolic short-axis diameters were made from apical views at several LV cavity levels. From upright rest to upright exercise the LV end-diastolic internal cavity measurements increased significantly. During exercise, the LV cavity became geometrically more spherical with the largest increase in the LV end-diastolic short-axis cavity diameters in the mid and apical parts of the left ventricle. The LV internal long axis showed significant increase from rest to exercise but the absolute increase was small.

Background Insulin resistance (IR) is a risk factor for diabetes and atherosclerotic diseases. The metabolic syndrome (MetS) reflects IR. Waist circumference (WC) is the most easily registered component of MetS. The objective was to compare WC alone with MetS as defined by the National Cholesterol Education Program (NCEP) and the International Diabetes Federation (IDF) for their abilities to predict IR in elderly without known diabetes. Methods The study included 223 women and 210 men comprising 70% of a random sample of 75-year-olds from a general population. IR was conventionally defined as the gender-specific upper quartile of the Homeostasis Model Assessment-Insulin Resistance (HOMA-IR) index in individuals without known diabetes. Results 1) The positive association between WC and IR is stronger in women than in men. 2) WC > 88 cm alone is nearly as good as MetS, using NCEP criteria, in predicting IR in women. 3) According to the ROC curve, the optimal cut-off point for WC predicting IR was between 96 and 97 cm (men) and between 88 and 89 cm (women). The relative risk of IR was 5.6 (95% CI: 3.1–11.9) for women with WC > 88 cm and 1.9 (1.5–2.8) for men with WC > 96 cm. 4) The NCEP criteria predicts IR significantly better than the IDF criteria. Conclusion WC > 88 cm in women indicates a high likelihood of IR and is almost as good as MetS defined using the NCEP criteria in predicting IR. MetS defined using the NCEP criteria predicts IR better than MetS defined using the IDF criteria.

Aims The study concerns the relationship of the corrected QT (QTc) interval to 6.4 years of survival and to measures of cardiac function, such as echocardiographic variables and plasma levels of brain natriuretic peptide (BNP), in 75-year-old people. Methods and results QTc was measured in a 12-lead electrocardiogram (ECG) in 210 men and 223 women, comprising a randomly selected sample from the general population (70% participation rate). The Sicard 440/740 computer-analysis program, with Hodges’ formula for heart rate-based QT correction, was used. The optimal cut-off point for predicting survival according to the receiver operating characteristic curve was found between 429 and 430 ms. Individuals with a QTc interval of � 430 ms (n ¼ 115) had decreased survival when compared with those with shorter QTc interval (n ¼ 318); the relative risk was 2.4 (95% confidence interval 1.5–3.7). The predictive ability of QTc reflects an association between QTc and the following variables: BNP, left ventricular mass, and left ventricular ejection fraction (but not diastolic filling patterns). Both Hodges’ and Bazett’s formulae for heart rate correction of the QT interval were useful for predicting survival. The median QTc was 415 ms using Hodges’ formula and 430 ms with Bazett’s formula. The QRS component of QTc predicted survival better than the rest of the QTc interval and was approximately as useful as the QTc interval itself. Conclusion The computer-derived QTc obtained from the ordinary 12-lead ECG identifies high-risk individuals among elderly people from the general population.

Background A considerable body of echocardiographic studies has described how athletic training induces morphological adaptation of the left ventricle in male endurance athletes, but only a few studies have described left ventricular adaptation in female endurance athletes. In contrast to changes in the left ventricle far less attention has been directed towards right ventricular changes due to extensive physical exercise. The purpose of this study was to obtain normal values and to determine if there are any differences in right and left ventricular cavity and wall dimensions between female orienteers and females with a mainly sedentary lifestyle. Methods Echocardiography was performed in 42 highly trained elite female orienteers and 32 healthy female students with a predominantly sedentary lifestyle. The 74 females had no history of cardiac disease, a normal electrocardiogram and showed no echocardiographic abnormalities. M-mode and two-dimensional measurements of the right and left ventricular cavity and wall were obtained in elite orienteers and sedentary females. For the right ventricle and wall, multiple cross-sections were used and measurements were obtained from the right ventricular inflow and outflow tract. Results The left ventricular end-diastolic cavity dimension and the left ventricular wall thickness were significantly greater in the athletes compared with the sedentary controls. The right ventricular inflow tract measurements were all significantly greater in the orienteers compared with the controls but the right ventricular outflow tract measurements were comparable in the study groups. The right ventricular wall thickness, calculated as the mean of three different wall measurements was an average of 13% greater in the athletes compared with the sedentary controls. Conclusion This study suggests symmetrical cardiac enlargement with a concomitant increase in both the right and left ventricular wall, probably reflecting the increased haemodynamic loading in the female athletes.

The aim of the present study was to quantify the left ventricular (LV) longitudinal motion during exercise at rest and during upright exercise in 24 healthy male endurance athletes. By using M-mode and two-dimensional echocardiography, the relative mitral annular motion and the absolute LV longitudinal axis was measured at end-diastole and end-systole at rest and during exercise. From rest to peak exercise at a heart rate of 160 beats per minute (bpm) the mitral annular motion increased in the septal and lateral annular borders by 68% and 49% respectively. At rest, mitral annular excursion was significantly (13%) higher in the lateral than in the septal wall but at peak exercise at a heart rate of 160 bpm there was no difference between the septal and lateral annular motion. The total end-diastolic LV axial length did not increase from rest to peak exercise. In conclusion, during upright exercise, mitral annular motion increased significantly with no difference between the septal and lateral annular excursion at peak exercise. The absolute increase in mitral annular motion during exercise was explained by a decrease in axial end-systolic length.

Background: Low heart rate recovery (HRR) at exercise test and the metabolic syndrome (MetS) are both predictors of cardiovascular morbidity and mortality. We studied in 75-year-old women and men, representative of the general population, the relationship between (1) HRR and the MetS, (2) HRR and the individual components of the MetS, and (3) HRR and insulin sensitivity. Methods: A cross-sectional study of randomly selected 75-year-olds from a general population was performed (191 women and 194 men). The MetS was defined according to the National Cholesterol Education Program criteria. Heart rate was measured as beats per minute immediately after exercise and at 4 minutes into recovery. Results: Heart rate recovery (median and interquartile range, beat/min) was 48 (37-58) for women and 49 (38-58) for men. Thirty-seven percent of the women and 25% of the men had the MetS. Heart rate recovery was 52 (42-61) for women with the MetS and 42 (31-49) for those without. The corresponding values for men was 50 (39-61) and 47 (35-54); the difference between individuals with and without the MetS was significant for women (P < .001) but not for men (P = .084). The following significant correlation coefficients between HRR and MetS components were found: for women, waist circumference (-0.43, P < .001), high-density lipoprotein cholesterol (0.37, P < .001), insulin sensitivity (-0.37, P < .001), fasting plasma glucose (-0.30, P < .001), and triglycerides (-0.24, P = .001); for men, triglycerides (-0.20, P = .005). The sex disparity in the strength of correlation reached statistical significance for insulin sensitivity (P < .001) and waist circumference (P = .042). Conclusion: Among 75-year-olds, the MetS and related components are more strongly correlated to HRR in women than in men.