ABSTRACT
Endothelial dysfunction has been recognized as a pathophysiologic mechanism in the progression of heart failure (HF). However, little attention has been given to the ability of dietary approaches to improve endothelial function. This study examined the effects of the Dietary Approaches to Stop Hypertension (DASH) diet on endothelial function, exercise capacity, and quality of life in patients with chronic symptomatic (stage C) HF. Forty-eight patients were randomized to follow the DASH diet (n = 24) or the general HF dietary recommendations (n = 24). Endothelial function was assessed by measuring large and small arterial elasticity (LAE and SAE) at rest. Exercise capacity (measured with the 6-minute walk test) and quality of life (measured with the Minnesota Living with Heart Failure Questionnaire) at baseline and 3 months were also evaluated. Patients were older adults with an average HF duration of 5 years. LAE at 1 month improved significantly in the DASH diet group (P < 0.01). Overall LAE and SAE scores at 3 months also improved; however, the net changes were not statistically significant. The DASH group had better exercise capacity (292 m vs 197 m; P = 0.018) and quality of life scores (21 vs 39; P = 0.006) over time, while sodium intake levels at 1, 2, and 3 months were comparable between the groups. Adhering to the DASH diet improved arterial compliance initially and improved exercise capacity and quality of life scores at 3 months. The DASH diet may be an important adjunctive therapy for patients with symptomatic HF.
ABSTRACT
Only early detection and treatment is likely to stem the current epidemic of heart failure (HF). Several common cardiovascular and metabolic conditions increase the risk of developing symptomatic HF, but its detection by a simple and reliable screening method has proved elusive. HF screening sessions were conducted in September and November 2001. Members of the community with HF risk factors (e.g., hypertension, coronary artery disease, diabetes mellitus, hyperlipidemia) were invited--all specifically without a history of HF. The screening included a history review, health history questionnaire, measurement of blood pressure and pulse, as well as a measurement of B-type natriuretic peptide (BNP) level. A total of 233 individuals attended these two sessions: 108 men and 125 women (mean age, 63 years). Of the 233 subjects screened, the majority (92%) had >or=1 risk factor with an average of 2.8 risk factors for HF. The most common risks included hyperlipidemia (112), hypertension (112), age >65 years (105), cigarette smoking (105), coronary artery disease (60), and diabetes mellitus (54). Many subjects also had symptoms consistent with HF, with most (182, 82%) recording >or=1 symptom. Blood pressure measurements revealed a mean systolic of 139 mm Hg and mean diastolic of 79 mm Hg; on the screening days, 48% and 59% of subjects demonstrated either systolic or diastolic blood pressures above normal, respectively. BNP levels ranged from 0-479 pg/mL with an average of 40 pg/mL. A total of 24 subjects (10.3%) had a BNP level >100 pg/mL, and a total of 32 subjects (13.7%) had a level >80 pg/mL. The follow-up data showed that all 24 subjects saw their physician within 6 months after the screening. By 12 months following the initial screening program, 21 of the 24 subjects with elevated BNP levels (88%) underwent further testing and 18 of the 24 (67%) had changes in their medications. BNP screening identifies subjects at high risk for developing HF. Most subjects at risk have multiple risk factors and abnormal blood pressure. Approximately 10% of this population tested with an abnormal level of BNP, higher than the Food and Drug Administration-assigned cut-point diagnostic for HF. Increased public and physician awareness and information are needed to transform screening opportunities into a strategic approach to improve health care and HF prevention.