Factors influencing QT prolongation in patients hospitalized with severe anorexia nervosa.

BACKGROUND: Anorexia nervosa (AN) carries the highest mortality of any psychiatric disorder largely attributable to sudden cardiac death and suicide. Controversy exists regarding the underlying mechanism of cardiac risk, whether QT prolongation is a consistent feature of the disorder and whether repolarization varies by disease severity. Some of the uncertainty may relate to a lack of standardized electrocardiography (ECG). To date, studies have not utilized centrally adjudicated digital ECG, and most have relied on the Bazett formula for rate-correction, which is suboptimal at the extremes of heart rate often observed in AN. METHODS: We evaluated a hospitalized cohort of medically compromised, very-low-body mass index (BMI) AN patients. The QT interval was measured with high-precision calipers by a single, blinded electrophysiologist and rate corrected (QTc) using the Fridericia formula. Anatomically corrected left ventricular (LV) mass and resting energy expenditure (REE) were calculated as proxies for disease severity. Proportions exceeding categorical thresholds for QTc prolongation and correlations between admission QTc and disease severity were performed. RESULTS: Among 19 patients, mean BMI was 12.3 kg/m(2), and 95% were female. The majority (68%) of patients were receiving QT-prolonging drugs. Four patients (21%) had QTc prolongation. Two of these patients (10.5%) exceeded the 500 ms threshold for marked QTc-prolongation, though each had concomitant factors contributing to delayed repolarization. The QTc interval was not significantly correlated with LV mass, LV mass index, BMI or REE. CONCLUSIONS: Although delayed cardiac repolarization was observed among a medically compromised cohort of patients with anorexia nervosa, the QTc interval was not a reliable correlate of disease severity despite digital ECG adjudication and optimal rate correction.

Lifestyle risk factors and utilization of preventive services in disabled elderly adults in the community.

Lifestyle risk factor counseling and preventive health services are important to disabled elderly adults to prevent adverse health outcomes. We aimed to examine the prevalence of lifestyle risk factors and utilization of preventive health services in community-dwelling 2,982 adults, aged 60 years or older, with or without disability, in Southeastern Pennsylvania in 2004. The severity of disability was classified as no [independent activities of daily living (ADL) and instrumental activities of daily living (IADL)], some (independent ADL, dependent IADL), and severe limitation (dependent ADL). The prevalence of lifestyle risk factors (cigarette smoking, obesity, binge alcohol use, unhealthy diet, and physical inactivity) and utilization rate of a comprehensive list of preventive health services (risk factor counseling, disease management, vaccination, and cancer screening) were measured, across the disability categories. The prevalence of disability was 14.6% for some limitation and 10.3% for severe limitation. As disability increases, participants with unhealthy diet, physical inactivity, and obesity became more prevalent (8.8, 15.7, and 25.2% for no, some, and severe limitation, respectively) and fewer osteoporosis screenings were performed (51.5, 38.8, and 37.8%). Utilization of other services did not vary significantly across the disability categories, but participants with some or severe limitation were less likely than those without to receive needed health services overall (19.3% or 16.2 vs. 24.2%; P for trend = .047). In conclusion, disabled elderly adults have more undesirable lifestyle risk factors, but are less likely to receive needed health services than nondisabled counterparts. More attention is needed to this vulnerable population.

Prevalence of hypovitaminosis D in cardiovascular diseases (from the National Health and Nutrition Examination Survey 2001 to 2004).

This cross-sectional study examined the burden of cardiovascular diseases (CVDs) using serum 25-hydroxyvitamin D (25[OH]D) and prevalence of hypovitaminosis D in adults with CVDs using data from NHANES 2001 to 2004. Serum 25(OH)D levels were divided into 3 categories (> or =30, 20 to 29, and <20 ng/ml), and hypovitaminosis D was defined as vitamin D <30 ng/ml. Of 8,351 adults who had 25(OH)D measured, mean 25(OH)D was 24.3 ng/ml, and the prevalence of hypovitaminosis D was 74%. The burden of CVDs increased with lower 25(OH)D categories, with 5.3%, 6.7%, and 7.3% coronary heart disease; 1.5%, 2.4%, and 3.2% heart failure; 2.5%, 2.0%, and 3.2% stroke; and 3.6%, 5.0%, and 7.7% peripheral arterial disease. Across all CVDs, hypovitaminosis D was more common in blacks than Hispanics or whites. Compared with persons at low risk for CVDs (68%), it was more prevalent in those at high risk (75%; odds ratio [OR] 1.32, 95% confidence interval [CI] 1.05 to 1.67), with coronary heart disease (77%; OR 1.48, 95% CI 1.14 to 1.91), and both coronary heart disease and heart failure (89%; OR 3.52, 95% CI 1.58 to 7.84) after controlling for age, race, and gender. In conclusion, hypovitaminosis D was highly prevalent in US adults with CVDs, particularly those with both coronary heart disease and heart failure.

Does body mass index really matter in the management of heart failure?: a review of the literature.

Excess body weight increases the risk for many disorders including cardiovascular disease and such patients have a greater risk for developing heart failure (HF). Despite evidence demonstrating the adverse effects of excess weight, the relationship between body mass index (BMI) and mortality in HF patients remains controversial. Paradoxically, several large cohort studies have shown that overweight and obese HF patients seem to have better survival than their healthy weight counterparts. The exact mechanism for this "obesity paradox" is not fully understood. Proposed mechanisms include a greater tolerance to angiotensin-converting enzyme inhibition, higher serum lipid levels, and the alteration of inflammatory cytokine metabolism in obese patients. Although the relationship between elevated BMI and improved survival has been well documented, recent clinical trials have not addressed this association. In 65 of 75 clinical HF trials reviewed, BMI as a potential independent predictor of outcomes was not addressed. Furthermore, the variation of pharmacokinetics in the obese population has been dealt with to a limited degree. If data concerning BMI and weight loss is to directly impact treatment recommendations for HF patients, well-designed clinical trials are needed.