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Kerry J Stewart

Publications and source records attributed to Kerry J Stewart.

9 recordsLinked to original sources
PubMed2003

Cardiac rehabilitation following percutaneous revascularization, heart transplant, heart valve surgery, and for chronic heart failure.

This review discusses the scientific and clinical evidence for cardiac rehabilitation in patients who have undergone percutaneous revascularization, heart transplant, and heart valve surgery, and in patients with chronic heart failure. Across these diagnoses, regardless of age, there is considerable benefit of cardiac rehabilitation and supervised exercise training for increasing functional capacity, favorably modifying disease-related risk factors, decreasing symptoms, detecting signs and symptoms of disease before they become serious complications, and improving quality of life. The available evidence for this component of cardiovascular disease management, albeit not perfect, still warrants its more widespread application.

Angioplasty, Balloon, Coronary↗
PubMed2002

Growth hormone and sex steroid administration in healthy aged women and men: a randomized controlled trial.

CONTEXT: Hormone administration to elderly individuals can increase lean body mass (LBM) and decrease fat, but interactive effects of growth hormone (GH) and sex steroids and their influence on strength and endurance are unknown. OBJECTIVE: To evaluate the effects of recombinant human GH and/or sex steroids on body composition, strength, endurance, and adverse outcomes in aged persons. DESIGN, SETTING, AND PARTICIPANTS: A 26-week randomized, double-blind, placebo-controlled parallel-group trial in healthy, ambulatory, community-dwelling US women (n = 57) and men (n = 74) aged 65 to 88 years recruited between June 1992 and July 1998. INTERVENTIONS: Participants were randomized to receive GH (starting dose, 30 micro g/kg, reduced to 20 micro g/kg, subcutaneously 3 times/wk) + sex steroids (women: transdermal estradiol, 100 micro g/d, plus oral medroxyprogesterone acetate, 10 mg/d, during the last 10 days of each 28-day cycle [HRT]; men: testosterone enanthate, biweekly intramuscular injections of 100 mg) (n = 35); GH + placebo sex steroid (n = 30); sex steroid + placebo GH (n = 35); or placebo GH + placebo sex steroid (n = 31) in a 2 x 2 factorial design. MAIN OUTCOME MEASURES: Lean body mass, fat mass, muscle strength, maximum oxygen uptake (VO(2)max) during treadmill test, and adverse effects. RESULTS: In women, LBM increased by 0.4 kg with placebo, 1.2 kg with HRT (P =.09), 1.0 kg with GH (P =.001), and 2.1 kg with GH + HRT (P<.001). Fat mass decreased significantly in the GH and GH + HRT groups. In men, LBM increased by 0.1 kg with placebo, 1.4 kg with testosterone (P =.06), 3.1 kg with GH (P<.001), and 4.3 kg with GH + testosterone (P<.001). Fat mass decreased significantly with GH and GH + testosterone. Women's strength decreased in the placebo group and increased nonsignificantly with HRT (P =.09), GH (P =.29), and GH + HRT (P =.14). Men's strength also did not increase significantly except for a marginally significant increase of 13.5 kg with GH + testosterone (P =.05). Women's VO(2)max declined by 0.4 mL/min/kg in the placebo and HRT groups but increased with GH (P =.07) and GH + HRT (P =.06). Men's VO(2)max declined by 1.2 mL/min/kg with placebo and by 0.4 mL/min/kg with testosterone (P =.49) but increased with GH (P =.11) and with GH + testosterone (P<.001). Changes in strength (r = 0.355; P<.001) and in VO(2)max (r = 0.320; P =.002) were directly related to changes in LBM. Edema was significantly more common in women taking GH (39% vs 0%) and GH + HRT (38% vs 0%). Carpal tunnel symptoms were more common in men taking GH + testosterone (32% vs 0%) and arthralgias were more common in men taking GH (41% vs 0%). Diabetes or glucose intolerance occurred in 18 GH-treated men vs 7 not receiving GH (P =.006). CONCLUSIONS: In this study, GH with or without sex steroids in healthy, aged women and men increased LBM and decreased fat mass. Sex steroid + GH increased muscle strength marginally and VO( 2)max in men, but women had no significant change in strength or cardiovascular endurance. Because adverse effects were frequent (importantly, diabetes and glucose intolerance), GH interventions in the elderly should be confined to controlled studies.

Aged↗
PubMed2002

Exercise training and the cardiovascular consequences of type 2 diabetes and hypertension: plausible mechanisms for improving cardiovascular health.

The coexistence of type 2 diabetes and hypertension is especially damaging to cardiovascular health. Most trials of exercise training for these conditions have focused on glycemic control and blood pressure reduction. Less is known about the effects of exercise on the cardiovascular consequences of diabetes and hypertension. This article reviews the available evidence and plausible mechanisms by which exercise training may improve the cardiovascular health of persons with type 2 diabetes and hypertension and provides practical guidelines for exercise prescription. A MEDLINE search was performed for January 1985 to June 2002. Bibliographies from relevant articles, professional society clinical practice guidelines, and books were also reviewed. Because few large, randomized trials exist on these topics, meta-analyses, smaller trials, nonrandomized trials, and animal studies were also considered. Data quality was determined by publication in peer-reviewed journals or professional society literature. Type 2 diabetes and hypertension result in abnormalities in central and peripheral parameters of cardiovascular structure and function. Evidence for an exercise training benefit is strongest for improvements in endothelial vasodilator function and left ventricular diastolic function. The data for exercise training's improvement of arterial stiffness and system inflammation and reduction of left ventricular mass are less robust. However, this assertion is based more on a lack of randomized controlled trials rather than data to the contrary. Exercise training also reduces total and abdominal fat. These changes in body composition mediate improvements in insulin sensitivity and blood pressure and may improve endothelial vasodilator function. The current evidence, albeit not fully confirmed in randomized trials, suggests that the benefits of exercise training go beyond the recognized benefits of glycemic control and blood pressure reduction.

Adipose Tissue↗
PubMed2002

Peripheral endothelium-dependent flow-mediated vasodilatation is associated with left ventricular mass in older persons with hypertension.

BACKGROUND: Increased left ventricular (LV) mass is associated with greater cardiovascular disease risk. Recent studies have also shown an association of increased LV mass with attenuated endothelium-dependent coronary flow reserve. Less is known about the association between LV mass and endothelium-dependent flow-mediated dilatation (FMD) in peripheral arteries, a noninvasive measure of endothelial function. METHODS: Sixty-two subjects with untreated mild hypertension, aged 55 to 75 years and otherwise healthy, were examined. Resting blood pressure was obtained by the average of 4 to 5 visits, each at least 1 week apart. LV mass was determined from magnetic resonance imaging and was indexed by body surface area, height and height(2.7). Body composition was assessed with dual energy x-ray absorptiometry. FMD was measured as the percent change of brachial artery diameter during reactive hyperemia by use of high-resolution ultrasound. RESULTS: Median LV mass index was 63 g/m2 (interquartile range, 58-73). In bivariate analysis, LV mass was correlated to lean body mass (r = 0.63, P <.001), diastolic blood pressure (r = 0.35, P <.01), and FMD (r = -0.27, P <.05). In multivariate analysis, 44% of the variance in log-LV mass was explained by lean body mass. An additional 6% of the variance was explained by FMD (P <.05). For each 1% point decrease in FMD, LV mass increased by 1.1%. CONCLUSIONS: In addition to the expected influences of body size, impairment of brachial artery FMD was independently related to LV mass in elderly subjects with mild hypertension who did not yet have LV hypertrophy. Whether mild hypertension is the common mechanism linking LV mass and endothelial function has yet to be determined.

Aged↗
PubMedDate not supplied

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.

Abdomen↗
PubMedDate not supplied

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.

Affect↗