Janssen Ian
School of Kinesiology and Health Studies, Department of Community Health and Epidemiology, Queen's University, Kingston, Ontario, Canada, K7L 3N6.
Obesity (Silver Spring). 2007 Jul;15(7):1827-40. doi: 10.1038/oby.2007.217.
There is controversy as to whether older adults with a BMI in the overweight range (25 to 29.9 kg/m2) are at increased health risk and whether they should be encouraged to lose weight. The purpose of this study was to determine whether older adults with a BMI in the overweight range are at increased morbidity and mortality risk.
Participants consisted of 4968 older (>or=65 years) men and women from the Cardiovascular Health Study limited access dataset. Based on BMI (kg/m2), participants were grouped into normal-weight (20 to 24.9 kg/m2), overweight (25 to 29.9 kg/m2), and obese (>or=30 kg/m2) categories. Participants were followed for up to 9 years to determine if they developed 10 weight-related health outcomes that are pertinent to older adults. Cox proportional hazards models were used to estimate the hazards ratios of morbidity and mortality after adjusting for age, sex, income, smoking, and physical activity.
Compared with the normal-weight group, the risks of myocardial infarction, stroke, sleep apnea, urinary incontinence, cancer, and osteoporosis were not different in the overweight group (p>0.05). The risks for arthritis and physical disability were modestly increased in the overweight group (p<0.05), whereas the risk for type 2 diabetes was increased by 78% in the overweight group (p<0.01). After adjusting for all relevant covariates, all-cause mortality risk was 11% lower in the overweight group (p<0.05).
A BMI in the overweight range was associated with some modest disease risks but a slightly lower overall mortality rate. These findings suggest that a BMI cut-off point of 25 kg/m2 may be overly restrictive for the elderly.
体重指数（BMI）处于超重范围（25至29.9千克/平方米）的老年人是否健康风险增加以及是否应鼓励他们减肥存在争议。本研究的目的是确定BMI处于超重范围的老年人发病和死亡风险是否增加。
参与者包括来自心血管健康研究有限访问数据集的4968名年龄≥65岁的男性和女性。根据BMI（千克/平方米），参与者被分为正常体重（20至24.9千克/平方米）、超重（25至29.9千克/平方米）和肥胖（≥30千克/平方米）类别。对参与者进行长达9年的随访，以确定他们是否出现了10种与老年人相关的体重相关健康结果。使用Cox比例风险模型在调整年龄、性别、收入、吸烟和身体活动后估计发病和死亡的风险比。
与正常体重组相比，超重组中心肌梗死、中风、睡眠呼吸暂停、尿失禁、癌症和骨质疏松症的风险没有差异（p>0.05）。超重组中关节炎和身体残疾的风险略有增加（p<0.05），而超重组中2型糖尿病的风险增加了78%（p<0.01）。在调整所有相关协变量后，超重组的全因死亡风险低11%（p<0.05）。
BMI处于超重范围与一些适度的疾病风险相关，但总体死亡率略低。这些发现表明，对于老年人来说，BMI截止点为25千克/平方米可能过于严格。
