Sytkowski P A, Kannel W B, D'Agostino R B
New England Research Institute, Watertown, MA 02172.
N Engl J Med. 1990 Jun 7;322(23):1635-41. doi: 10.1056/NEJM199006073222304.
A decline in mortality from cardiovascular disease over the past 30 years has been well documented, but the reasons for the decline remain unclear. We analyzed the 10-year incidence of cardiovascular disease and death from cardiovascular disease in three groups of men who were 50 to 59 years old at base line in 1950, 1960, and 1970 (the 1950, 1960, and 1970 cohorts) in order to determine the contribution of secular trends in the incidence of cardiovascular disease, risk factors, and medical care to the decline in mortality. The 10-year cumulative mortality from cardiovascular disease in the 1970 cohort was 43 percent less than that in the 1950 cohort and 37 percent less than that in the 1960 cohort (P = 0.04 by log-rank test). Among the men who were free of cardiovascular disease at base line, the 10-year cumulative incidence of cardiovascular disease declined approximately 19 percent, from 190 per 1000 in the 1950 cohort to 154 per 1000 in the 1970 cohort (0.10 less than P less than 0.20 by chi-square test), whereas the 10-year rate of death from cardiovascular disease declined 60 percent (relative risk for the 1950 cohort as compared with the 1970 cohort, 2.53; 95 percent confidence interval, 1.22 to 5.97). Significant improvements were found in risk factors for cardiovascular disease among the men initially free of cardiovascular disease in the 1970 cohort as compared with those in the 1950 cohort, including a lower serum cholesterol level (mean +/- SD, 5.72 +/- 0.98 mmol per liter [221 +/- 38 mg per deciliter], as compared with 5.90 +/- 1.03 mmol per liter [228 +/- 40 mg per deciliter]) and a lower systolic blood pressure (mean +/- SD, 135 +/- 19 mm Hg, as compared with 139 +/- 25 mm Hg), better management of hypertension (22 percent vs. 0 percent were receiving antihypertensive medication), and reduced cigarette smoking (34 percent vs. 56 percent). We propose that these improvements may have had more pronounced effects on mortality from cardiovascular disease than on the incidence of cardiovascular disease in this population. Our data suggest that the improvement in cardiovascular risk factors in the 1970 cohort may have been an important contributor to the 60 percent decline in mortality in that group as compared with the 1950 cohort, although a decline in the incidence of cardiovascular disease and improved medical interventions may also have contributed to the decline in mortality.
过去30年中心血管疾病死亡率的下降已有充分记录，但下降的原因仍不清楚。我们分析了1950年、1960年和1970年基线时年龄在50至59岁的三组男性（1950年、1960年和1970年队列）中心血管疾病的10年发病率和心血管疾病死亡率，以确定心血管疾病发病率、危险因素和医疗护理的长期趋势对死亡率下降的贡献。1970年队列中心血管疾病的10年累积死亡率比1950年队列低43%，比1960年队列低37%（对数秩检验P = 0.04）。在基线时无心血管疾病的男性中，心血管疾病的10年累积发病率下降了约19%，从1950年队列中的每1000人190例降至1970年队列中的每1000人154例（卡方检验0.10＜P＜0.20），而心血管疾病的10年死亡率下降了60%（1950年队列与1970年队列相比的相对风险为2.53；95%置信区间为1.22至5.97）。与1950年队列相比，1970年队列中最初无心血管疾病的男性心血管疾病危险因素有显著改善，包括血清胆固醇水平较低（平均±标准差，5.72±0.98 mmol/L[221±38 mg/dL]，而1950年队列中为5.90±1.03 mmol/L[228±40 mg/dL]）和收缩压较低（平均±标准差，135±19 mmHg，而1950年队列中为139±25 mmHg），高血压管理更好（接受抗高血压药物治疗的比例为22%对0%），以及吸烟减少（34%对56%）。我们认为，这些改善对该人群心血管疾病死亡率的影响可能比对心血管疾病发病率的影响更为显著。我们的数据表明，与1950年队列相比，1970年队列中心血管疾病危险因素的改善可能是该组死亡率下降60%的一个重要因素，尽管心血管疾病发病率的下降和医疗干预的改善也可能对死亡率的下降有所贡献。
