Bogers Rik P, Bemelmans Wanda J E, Hoogenveen Rudolf T, Boshuizen Hendriek C, Woodward Mark, Knekt Paul, van Dam Rob M, Hu Frank B, Visscher Tommy L S, Menotti Alessandro, Thorpe Roland J, Jamrozik Konrad, Calling Susanna, Strand Bjørn Heine, Shipley Martin J
Centre for Prevention and Health Services Research, National Institute for Public Health and the Environment, PO Box 1, 3720 BA Bilthoven, The Netherlands.
Arch Intern Med. 2007 Sep 10;167(16):1720-8. doi: 10.1001/archinte.167.16.1720.
The extent to which moderate overweight (body mass index [BMI], 25.0-29.9 [calculated as weight in kilograms divided by height in meters squared]) and obesity (BMI, >/= 30.0) are associated with increased risk of coronary heart disease (CHD) through adverse effects on blood pressure and cholesterol levels is unclear, as is the risk of CHD that remains after these mediating effects are considered.
Relative risks (RRs) of CHD associated with moderate overweight and obesity with and without adjustment for blood pressure and cholesterol concentrations were calculated by the members of a collaboration of prospective cohort studies of healthy, mainly white persons and pooled by means of random-effects models (RRs for categories of BMI in 14 cohorts and for continuous BMI in 21 cohorts; total N = 302 296).
A total of 18 000 CHD events occurred during follow-up. The age-, sex-, physical activity-, and smoking-adjusted RRs (95% confidence intervals) for moderate overweight and obesity compared with normal weight were 1.32 (1.24-1.40) and 1.81 (1.56-2.10), respectively. Additional adjustment for blood pressure and cholesterol levels reduced the RR to 1.17 (1.11-1.23) for moderate overweight and to 1.49 (1.32-1.67) for obesity. The RR associated with a 5-unit BMI increment was 1.29 (1.22-1.35) before and 1.16 (1.11-1.21) after adjustment for blood pressure and cholesterol levels.
Adverse effects of overweight on blood pressure and cholesterol levels could account for about 45% of the increased risk of CHD. Even for moderate overweight, there is a significant increased risk of CHD independent of these traditional risk factors, although confounding (eg, by dietary factors) cannot be completely ruled out.
中度超重（体重指数[BMI]，25.0 - 29.9[计算方法为体重（千克）除以身高（米）的平方]）和肥胖（BMI，≥30.0）通过对血压和胆固醇水平产生不利影响而与冠心病（CHD）风险增加相关的程度尚不清楚，在考虑这些中介作用后仍存在的冠心病风险也不明确。
由一项针对健康的、主要为白人的前瞻性队列研究合作项目的成员计算出与中度超重和肥胖相关的冠心病相对风险（RRs），计算时分别调整和未调整血压及胆固醇浓度，并通过随机效应模型进行汇总（14个队列中BMI分类的RRs以及21个队列中连续BMI的RRs；总样本量N = 302296）。
随访期间共发生18000例冠心病事件。与正常体重相比，经年龄、性别、体力活动和吸烟调整后的中度超重和肥胖的RRs（95%置信区间）分别为1.32（1.24 - 1.40）和1.81（1.56 - 2.10）。进一步调整血压和胆固醇水平后，中度超重的RR降至1.17（1.11 - 1.23），肥胖的RR降至1.49（1.32 - 1.67）。在调整血压和胆固醇水平之前，与BMI增加5个单位相关的RR为1.29（1.22 - 1.35），调整后为1.16（1.11 - 1.21）。
超重对血压和胆固醇水平的不利影响可能占冠心病风险增加的约45%。即使是中度超重，独立于这些传统风险因素之外，冠心病风险也显著增加，尽管不能完全排除混杂因素（如饮食因素）的影响。
