Randomized trial of hormone therapy in women after coronary bypass surgery. Evidence of differential effect of hormone therapy on angiographic progression of disease in saphenous vein grafts and native coronary arteries.

Clinical trials indicate that hormone therapy (HT) does not decrease cardiovascular disease events or angiographic coronary disease progression. The effects of HT on SVG vessels are unknown. To determine whether postmenopausal hormone therapy started after coronary bypass surgery (CABG) decreases saphenous vein graft (SVG) disease, we conducted a multicenter randomized placebo-controlled angiographic study of estradiol+/-medroxyprogesterone started within 6 months of CABG in 83 postmenopausal women. Angiographic and intravascular ultrasound (IVUS) assessment at 6 and 42 months was planned to assess SVG disease progression. The study was stopped early following publication of the Women's Health Initiative Estrogen/Progestin study. Eighty-three subjects underwent a 6-month angiogram with 63 undergoing IVUS. Forty-five subjects completed the 42-month angiogram (20 underwent 42-month IVUS). In analysis of paired 6- and 42-month angiogram and IVUS studies, HT slowed angiographic progression of SVG disease assessed by mean percent stenosis (p<0.001), minimal lumen diameter (p=0.029), and total plaque volume (p=0.006). In contrast, HT accelerated disease progression in non-bypassed native coronary arteries (minimum lumen diameter, p=0.01). SVG disease and closure occurred in 38% subjects within 1-year post-CABG. The groups had similar frequency of cardiovascular events expect for angioplasty that occurred in eight HT compared to one placebo subject (p<0.05). In HT subjects angioplasty was indicated for native coronary arterial stenoses while in the placebo subject angioplasty was indicated for SVG stenosis. This study suggests that hormone treatment may slow SVG disease progression while accelerating atherosclerosis in non-bypassed native coronary arteries.

Effect of exercise on blood pressure in older persons: a randomized controlled trial.

BACKGROUND: Because of age-related differences in the cause of hypertension, it is uncertain whether current exercise guidelines for reducing blood pressure (BP) are applicable to older persons. Few exercise studies in older persons have evaluated BP changes in relation to changes in body composition or fitness. METHODS: This was a 6-month randomized controlled trial of combined aerobic and resistance training; controls followed usual care physical activity and diet advice. Participants (aged 55-75 years) had untreated systolic BP (SBP) of 130 to 159 mm Hg or diastolic BP (DBP) of 85 to 99 mm Hg. RESULTS: Fifty-one exercisers and 53 controls completed the trial. Exercisers significantly improved aerobic and strength fitness, increased lean mass, and reduced general and abdominal obesity. Mean decreases in SBP and DBP, respectively, were 5.3 and 3.7 mm Hg among exercisers and 4.5 and 1.5 mm Hg among controls (P < .001 for all). There were no significant group differences in mean SBP change from baseline (-0.8 mm Hg; P=.67). The mean DBP reduction was greater among exercisers (-2.2 mm Hg; P=.02). Aortic stiffness, indexed by aortofemoral pulse-wave velocity, was unchanged in both groups. Body composition improvements explained 8% of the SBP reduction (P = .006) and 17% of the DBP reduction (P<.001). CONCLUSIONS: A 6-month program of aerobic and resistance training lowered DBP but not SBP in older adults with mild hypertension more than in controls. The concomitant lack of improvement in aortic stiffness in exercisers suggests that older persons may be resistant to exercise-induced reductions in SBP. Body composition improvements were associated with BP reductions and may be a pathway by which exercise training improves cardiovascular health in older men and women.

Exercise effects on bone mineral density relationships to changes in fitness and fatness.

BACKGROUND: Weight loss typically reduces bone mineral density (BMD). Exercise may preserve or increase BMD even while reducing fatness. We examined the relationships among exercise-induced changes in fitness and fatness with BMD. DESIGN: Randomized controlled trial conducted between July 1999 and November 2003. PARTICIPANTS: Men and women (n =115) aged 55 to 75 years. INTERVENTION: Six months of exercise training. MAIN OUTCOME MEASURES: Fitness measured as peak oxygen uptake and muscle strength, body composition by anthropometry, dual-energy x-ray absorptiometry, and magnetic resonance imaging. RESULTS: A total of 51 men and 53 women completed the trial. Exercise increased aerobic and strength fitness and lean body mass, and reduced general and abdominal obesity. BMD did not change among men in either group. Among women exercisers, there were reductions in total skeleton BMD (p =0.02) and greater trochanter BMD (p =0.02). By bivariate correlation, among women, increased femoral neck BMD was associated with increased aerobic fitness (p =0.01) and with reduced body weight (p =0.02) and BMI (p =0.02). In the final regression model, 13% of the change in femoral neck BMD was explained by the change in aerobic fitness (p <0.01). Among the men, increased total hip BMD and femoral shaft BMD were associated with increased lean mass and lower-body strength. In the final regression models, the change in lean mass explained 9% of the variance in total hip BMD (p =0.04). The change in lean mass explained 20% of the change in femoral shaft BMD (p <0.01), and the change in lower-body strength explained an additional 6% (p <0.04). CONCLUSIONS: When examined by group assignment, 6 months of exercise had no effect on BMD among men, and reduced BMD among women. When examined by change in fitness and fatness, women who had the greatest increases in aerobic capacity and men who had the greatest increases in strength and lean mass were more likely to increase their BMD. Exercise-induced reductions in fatness did not lead to bone loss.

Exercise and risk factors associated with metabolic syndrome in older adults.

BACKGROUND: Older people with elevated blood pressure (BP) often have metabolic syndrome, a clustering of central obesity, insulin resistance, dyslipidemia, and hypertension. Exercise reduces many of these risk factors. This study examined whether the benefits of exercise on cardiovascular and metabolic disease risk factors are mediated by exercise-induced changes in fitness or body composition. METHODS: Randomized controlled trial, comprising 6 months of exercise training, conducted between July 1999 and November 2003. Participants included men and women (n =115) aged 55 to 75 years with untreated systolic blood pressure (SBP) of 130 to 159 or diastolic blood pressure of (DPB) 85 to 99 mm Hg. Fitness measures included BP, lipids, lipoproteins, insulin, and glucose; peak oxygen uptake and muscle strength; and body composition measured by anthropometry, dual-energy x-ray absorptiometry, and magnetic resonance imaging. RESULTS: A total of 51 men and 53 women completed the trial. Exercise significantly increased aerobic and muscle fitness, lean mass, and high-density lipoprotein cholesterol and reduced total and abdominal fat. DBP was reduced more among exercisers. There were no associations among changes in fitness with risk factors. Reductions in total body and abdominal fat and increases in leanness, largely independent of weight loss, were associated with improved SBP, DBP, total cholesterol, very low-density lipoprotein cholesterol, triglycerides, lipoprotein(a), and insulin sensitivity. At baseline, 42.3% of participants had metabolic syndrome. At 6 months, nine exercisers (17.7%) and eight controls (15.1%) no longer had metabolic syndrome, whereas four controls (7.6%) and no exercisers developed it (p =0.06). CONCLUSIONS: Although exercise improved fitness, the reductions in total and abdominal fatness and increase in leanness were more strongly associated with favorable changes in risk factors for cardiovascular disease and diabetes, including those that constitute metabolic syndrome.

Are fitness, activity, and fatness associated with health-related quality of life and mood in older persons?

PURPOSE: This study sought to determine whether levels of fitness, habitual physical activity, and fatness are associated health-related quality of life and mood in older persons. METHODS: The subjects were men (n = 38) and women (n = 44), ages 55 to 75 years, who had milder forms of hypertension, but who were otherwise healthy and not engaged in a regular exercise or diet program. Aerobic fitness was assessed by maximal oxygen uptake during treadmill testing, muscle strength by a one-repetition maximum, habitual activity by questionnaire, fatness by dual-energy x-ray absorptiometry, and body mass index. Health-related quality of life was assessed by the Medical Outcomes Study SF-36, and mood by the Profile of Mood States (POMS). Correlations were determined by bivariate and multivariate regression. RESULTS: Higher aerobic fitness was associated with more desirable outcomes, as indicated by the POMS anger and total mood disturbance scores and by the SF-36 bodily pain, physical functioning, vitality, and physical component scores. Increased fatness was associated with less desirable outcomes, as indicated by the POMS anger, depression, and total mood disturbance scores and by the SF-36 bodily pain, physical functioning, role-emotional, role-physical, social functioning, vitality, and physical component scores. Higher physical activity was associated with an increased POMS score for vigor and a decreased SF-36 score for bodily pain. Strength was not related to health-related quality of life or mood. Aerobic fitness was the strongest predictor of the SF-36 score for vitality and the POMS score for total mood disturbance, whereas fatness was the strongest predictor of the POMS anger score and the SF-36 bodily pain, physical functioning, and physical component scores. CONCLUSIONS: Even in the absence of regular exercise and a weight-loss diet, relatively small amounts of routine physical activity within a normal lifestyle, slight increases in fitness, and less body fatness are associated with a better health-related quality of life and mood.

Usefulness of anthropometrics and dual-energy x-ray absorptiometry for estimating abdominal obesity measured by magnetic resonance imaging in older men and women.

PURPOSE: Increasing evidence suggests that abdominal obesity may be a better predictor of disease risk than total fatness. This study sought to determine how obesity and fat distribution measured by readily available anthropometric and dual-energy x-ray absorptiometry (DXA) methods is related to abdominal obesity assessed by magnetic resonance imaging (MRI). METHODS: Men (n = 43) and women (n = 47), ages 55 to 75 years, were assessed for body mass index, waist-to-hip ratio, waist circumference, and skin folds by anthropometric methods; for percentage of body fat by DXA; and for abdominal total, subcutaneous, and visceral fat by MRI. RESULTS: In stepwise regression models, the waist-to-hip ratio explained 50% of the variance in abdominal visceral fat among men (P <.01), and body mass index explained an additional 6% of the variance (P <.01). Among women, waist circumference was the only independent correlate of abdominal visceral fat, accounting for 52% of the variance (P <.01). Among men, the percentage of body fat was the only independent correlate of abdominal subcutaneous fat, explaining 65% of the variance (P <.01). Among women, the percentage of body fat explained 77% of the variance in abdominal subcutaneous fat and body mass index explained an additional 3% (P <.01). CONCLUSIONS: Obesity and body composition obtained by readily available anthropometric methods and DXA provide informative estimates of abdominal obesity assessed by MRI imaging.