Allender P S, Cutler J A, Follmann D, Cappuccio F P, Pryer J, Elliott P
Division of Epidemiology and Clinical Applications, National Heart, Lung, and Blood Institute, Bethesda, MD 20892 USA.
Ann Intern Med. 1996 May 1;124(9):825-31. doi: 10.7326/0003-4819-124-9-199605010-00007.
To assess the effect of dietary calcium supplementation on blood pressure.
Published reports of trials studying the effect of dietary calcium supplementation on blood pressure were identified by a search of previous reviews, a MEDLINE search, a manual review of journal articles, and a review of abstracts from scientific meetings.
Randomized clinical trials in which dietary calcium intake varied by intervention group were selected. Multifactorial trials were not included.
Data from 28 active treatment arms or strata from 22 randomized clinical trials were pooled using a weighted average method, with weights proportional to the inverse of the variance of the treatment effect. The total sample comprised 1231 persons. Because trials of both normotensive and hypertensive persons were included, subgroup analyses could be done. Pooled estimates of the effect of calcium supplementation on blood pressure were -0.18 mm Hg for diastolic blood pressure (95% CI, -0.75 to 0.40 mm Hg) and -0.89 mm Hg for systolic blood pressure (CI, -1.74 to -0.05 mm Hg). Pooled estimates for systolic blood pressure were -0.53 mm Hg (CI, -1.56 to 0.49 mm Hg) for trials of normotensive persons and -1.68 mm Hg (CI, -3.18 to -0.18 mm Hg) for trials of hypertensive persons. Diastolic blood pressure was not significantly affected in either subgroup.
The pooled estimate shows a statistically significant decrease of systolic blood pressure with calcium supplementation, both for hypertensive persons and for the overall sample. However, the effect is too small to support the use of calcium supplementation for preventing or treating hypertension.
评估膳食补钙对血压的影响。
通过检索既往综述、医学文献数据库（MEDLINE）、人工查阅期刊文章以及查阅科学会议摘要，确定了有关膳食补钙对血压影响的已发表试验报告。
选取干预组膳食钙摄入量不同的随机临床试验。不包括多因素试验。
采用加权平均法汇总了来自22项随机临床试验的28个积极治疗组或分层的数据，权重与治疗效果方差的倒数成正比。总样本包括1231人。由于纳入了血压正常者和高血压患者的试验，因此可以进行亚组分析。补钙对血压影响的合并估计值为舒张压-0.18 mmHg（95%置信区间，-0.75至0.40 mmHg），收缩压-0.89 mmHg（置信区间，-1.74至-0.05 mmHg）。血压正常者试验的收缩压合并估计值为-0.53 mmHg（置信区间，-1.56至0.49 mmHg），高血压患者试验的收缩压合并估计值为-1.68 mmHg（置信区间，-3.18至-0.18 mmHg）。两个亚组的舒张压均未受到显著影响。
合并估计显示，无论是高血压患者还是总体样本，补钙均使收缩压在统计学上显著降低。然而，该效果过小，不足以支持使用补钙来预防或治疗高血压。
