Health outcomes of gastric bypass patients compared to nonsurgical, nonintervened severely obese

Favorable health outcomes at 2 years postbariatric surgery have been reported. With exception of the Swedish Obesity Subjects (SOS) study, these studies have been surgical case series, comparison of surgery types, or surgery patients compared to subjects enrolled in planned nonsurgical intervention. This study measured gastric bypass effectiveness when compared to two separate severely obese groups not participating in designed weight-loss intervention. Three groups of severely obese subjects (N = 1,156, BMI >or= 35 kg/m(2)) were studied: gastric bypass subjects (n = 420), subjects seeking gastric bypass but did not have surgery (n = 415), and population-based subjects not seeking surgery (n = 321). Participants were studied at baseline and 2 years. Quantitative outcome measures as well as prevalence, incidence, and resolution rates of categorical health outcome variables were determined. All quantitative variables (BMI, blood pressure, lipids, diabetes-related variables, resting metabolic rate (RMR), sleep apnea, and health-related quality of life) improved significantly in the gastric bypass group compared with each comparative group (all P < 0.0001, except for diastolic blood pressure and the short form (SF-36) health survey mental component score at P < 0.01). Diabetes, dyslipidemia, and hypertension resolved much more frequently in the gastric bypass group than in the comparative groups (all P < 0.001). In the surgical group, beneficial changes of almost all quantitative variables correlated significantly with the decrease in BMI. We conclude that Roux-en-Y gastric bypass surgery when compared to severely obese groups not enrolled in planned weight-loss intervention was highly effective for weight loss, improved health-related quality of life, and resolution of major obesity-associated complications measured at 2 years.

The effects of nesiritide on renal function and diuretic responsiveness in acutely decompensated heart failure patients with renal dysfunction

BACKGROUND

Strategies to preserve renal function and enhance diuretic responsiveness during therapy for heart failure (HF) are needed. We hypothesized that brain natriuretic peptide (nesiritide) added to standard HF therapy would preserve renal function and enhance diuretic responsiveness.

METHODS

Patients with HF with underlying renal dysfunction who were admitted with volume overload were randomized to standard therapy with nesiritide (2 mug/kg bolus; 0.01 mug/kg/min for 48 hours) or without nesiritide. Patients requiring intravenous vasodilator or inotropic therapy for rapid symptom relief were ineligible. In all patients, diuretics were administered according to a standardized dosing algorithm.

RESULTS

Patients (n = 72) had a mean creatinine level of 1.75 +/- 0.59 mg/dL. Patients receiving nesiritide had a lesser increase in creatinine (P = .048) and blood urea nitrogen (P = .02), but a greater reduction in blood pressure (P < .01). Nesiritide did not enhance diuretic responsiveness (P = .57) but increased 3'5' cyclic guanosine monophosphate and decreased endothelin more (P < .05 for both). There were no differences in the change in atrial natriuretic peptide, N-terminal pro-brain natriuretic peptide, plasma renin activity, angiotensin II, and aldosterone between groups.

CONCLUSION

When used as adjuvant "renal protective" therapy in patients with HF with renal dysfunction, the recommended dose of nesiritide reduced blood pressure, did not seem to worsen renal function, and suppressed endothelin but did not enhance diuretic responsiveness or prevent activation of the renin-angiotensin-aldosterone system.

Advanced glycation end products accumulate in vascular smooth muscle and modify vascular but not ventricular properties in elderly hypertensive canines

BACKGROUND

Advanced glycation end products (AGEs) are believed to increase left ventricular (LV) and vascular stiffness, in part via cross-linking proteins. We determined whether and where AGEs were increased in elderly hypertensive nondiabetic dogs and whether an AGE cross-link breaker (ALT-711) improved vascular or ventricular function.

METHODS AND RESULTS

Elderly dogs with experimental hypertension (old hypertensives [OH]) were randomized to receive ALT-711 (OH+ALT group; n=11; 1 mg/kg PO) or not (OH group; n=11) for 8 weeks. Conscious blood pressure measurements (weekly), echocardiography (week 8), and anesthetized study (week 8) with LV pressure-volume analysis and aortic pressure-dimension and pressure-flow assessment over a range of preloads and afterloads were performed. In LV and aorta from OH, OH+ALT, and young normal dogs, AGE content (immunohistochemistry and Western analysis for N(epsilon)-(carboxymethyl)lysine [CML]) was assessed. Aortic CML content was markedly increased in OH and OH+ALT dogs compared with young normal dogs. CML was localized to aortic and aortic vasa vasorum smooth muscle but not to collagen or elastin. CML was essentially undetectable in young normal, OH, or OH+ALT myocardium but was visible in large vessels in the LV. ALT-711 therapy was associated with lower blood pressure and pulse pressure, decreased systemic vascular resistance, increased aortic distensibility and arterial compliance, and, notably, significant aortic dilatation. Neither LV systolic nor diastolic function was different in OH+ALT versus OH dogs.

CONCLUSIONS

In elderly hypertensive canines, AGE accumulation and AGE cross-link breaker effects were confined to the vasculature without evidence of myocardial accumulation or effects. The lack of AGE accumulation in collagen-rich areas suggests that the striking vascular effects may be mediated by mechanisms other than collagen cross-linking.

Mineralocorticoid Signaling in Transition to Heart Failure With Normal Ejection Fraction

Heart failure with normal ejection fraction occurs in elderly patients with hypertensive heart disease. We hypothesized that, in such patients, mineralocorticoid receptor activation accelerates the types of ventricular and vascular remodeling and dysfunction believed important in the transition to heart failure. We tested this hypothesis by administering deoxycorticosterone acetate (DOCA) without salt loading or nephrectomy to elderly dogs with experimental hypertension. Elderly dogs were made hypertensive by renal wrapping. After 5 weeks, dogs were randomly assigned to DOCA (1 mg/kg per day IM; old hypertensive [OH]+DOCA; n=11) or not (OH; n=11) for 3 weeks. At week 8, conscious echocardiography and hemodynamic assessment under anesthesia were performed. DOCA resulted in further increases in conscious blood pressure ( P <0.05) without increases in cardiac output or diastolic volume. In the conscious state, effective arterial elastance ( P <0.05) and systemic vascular resistance ( P =0.06) were increased, and systemic arterial compliance ( P <0.05) was decreased in OH+DOCA animals. After anesthesia, instrumentation, and autonomic blockade, blood pressure was lower, whereas left ventricular (LV) systolic elastance, LV diastolic stiffness, and ex vivo myofiber diastolic stiffness were increased in OH+DOCA animals. LV collagen was increased in OH+DOCA animals ( P <0.05 for all), but LV mass, LV brain natriuretic peptide, and titin isoform profiles were not. Neither aortic stiffness nor aortic structure was altered in OH+DOCA animals. These findings suggest that age and hypertensive heart disease enhance sensitivity to exogenous mineralocorticoid administration and that mineralocorticoid receptor activation could contribute to the transition to heart failure in elderly persons by promoting increases in LV diastolic and systolic stiffness.

Secular trends in renal dysfunction and outcomes in hospitalized heart failure patients

BACKGROUND

Renal dysfunction and worsening renal function (WRF) during heart failure (HF) therapy predict outcomes. We determined whether the severity of renal dysfunction, the incidence of WRF or outcomes have changed over time (secular trends) in patients hospitalized for HF therapy.

METHODS AND RESULTS

A total of 6440 consecutive unique patients admitted for HF to Mayo Clinic Hospitals Rochester, MN, January 1, 1987, to December 31, 2002, were identified and data extracted from electronic databases. Over the study period, age and admission creatinine increased, whereas estimated glomerular filtration rate and hemoglobin decreased (P < .0001 for all). The prevalence of hypertension and diabetes among HF patients also increased over time (P < .0001). The incidence of WRF was stable. Renal dysfunction and development of WRF were associated with mortality. When adjusted for the changes in baseline characteristics of HF patients, mortality declined over the study period.

CONCLUSION

Hospitalized HF patients are increasingly elderly, have a greater prevalence of diseases that lead to renal dysfunction, and have more severe renal dysfunction and anemia on admission. However, adjusting for these secular trends in patient characteristics, mortality after HF admission is improving. These data enhance our understanding of the changing natural history of HF.

Trends in prevalence and outcome of heart failure with preserved ejection fraction

BACKGROUND

The prevalence of heart failure with preserved ejection fraction may be changing as a result of changes in population demographics and in the prevalence and treatment of risk factors for heart failure. Changes in the prevalence of heart failure with preserved ejection fraction may contribute to changes in the natural history of heart failure. We performed a study to define secular trends in the prevalence of heart failure with preserved ejection fraction among patients at a single institution over a 15-year period.

METHODS

We studied all consecutive patients hospitalized with decompensated heart failure at Mayo Clinic Hospitals in Olmsted County, Minnesota, from 1987 through 2001. We classified patients as having either preserved or reduced ejection fraction. The patients were also classified as community patients (Olmsted County residents) or referral patients. Secular trends in the type of heart failure, associated cardiovascular disease, and survival were defined.

RESULTS

A total of 6076 patients with heart failure were discharged over the 15-year period; data on ejection fraction were available for 4596 of these patients (76 percent). Of these, 53 percent had a reduced ejection fraction and 47 percent had a preserved ejection fraction. The proportion of patients with the diagnosis of heart failure with preserved ejection fraction increased over time and was significantly higher among community patients than among referral patients (55 percent vs. 45 percent). The prevalence rates of hypertension, atrial fibrillation, and diabetes among patients with heart failure increased significantly over time. Survival was slightly better among patients with preserved ejection fraction (adjusted hazard ratio for death, 0.96; P=0.01). Survival improved over time for those with reduced ejection fraction but not for those with preserved ejection fraction.

CONCLUSIONS

The prevalence of heart failure with preserved ejection fraction increased over a 15-year period, while the rate of death from this disorder remained unchanged. These trends underscore the importance of this growing public health problem.