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「Epidemiology and causes of heart failure」のまとめを復習です。
The worldwide magnitude of the heart failure (HF) problem cannot be assessed with precision since reliable, population-based estimates of its prevalence, incidence, and prognosis are lacking for many regions of the globe, and a variety of methods that include history, physical examination, and heart function have been used to diagnose the condition. There were an estimated 5.8 million people with HF in the United States in 2006. There are an estimated 23 million people with HF worldwide.
The prevalence and incidence of HF increases with age, and trend data suggest that the prevalence in the United States has increased in persons aged >65 years.
Risk factors for HF include coronary heart disease, cigarette smoking, hypertension, overweight, diabetes, and valvular heart disease.
Prevention of HF requires early detection and treatment of predisposing conditions and of high-risk candidates by internists and general practitioners. The high risk for HF associated with hypertension, diabetes, coronary disease, and obesity identifies these as priority areas for preventive efforts.
Early detection of asymptomatic patients with a left ventricular ejection fraction (LVEF) ≤40 percent is important because effective therapy delays the onset of HF and prolongs life.
P : patients with asymptomatic left ventricular dysfunction
E : enalapril (n = 2111) at doses of 2.5 to 20 mg per day
C : placebo (n = 2117)
O : There were 334 deaths in the placebo group, as compared with 313 in the enalapril group (reduction in risk, 8 percent by the log-rank test; 95 percent confidence interval, -8 percent [an increase of 8 percent] to 21 percent; P = 0.30).
The reduction in mortality from cardiovascular causes was larger but was not statistically significant (298 deaths in the placebo group vs. 265 in the enalapril group; risk reduction, 12 percent; 95 percent confidence interval, -3 to 26 percent; P = 0.12).
we combined patients in whom heart failure developed and those who died, the total number of deaths and cases of heart failure was lower in the enalapril group than in the placebo group (630 vs. 818; risk reduction, 29 percent; 95 percent confidence interval, 21 to 36 percent; P less than 0.001).
fewer patients given enalapril died or were hospitalized for heart failure (434 in the enalapril group; vs. 518 in the placebo group; risk reduction, 20 percent; 95 percent confidence interval, 9 to 30 percent; P less than 0.001).