老年人BMI与高血压发生风险的相关性研究

Relationship between body mass index and incident hypertension in elderly people:a cohort study

目的 拟探讨老年人体质量指数(body mass index, BMI)与高血压发生风险的关系,为老年人适宜BMI范围制定提供参考。方法 收集上海交通大学医学院附属仁济医院体检中心老年研究对象(≥60岁)共9 474例资料,其中男性5 337例,女性4 137例。所有研究对象均随访5年。基线资料为2014年的身高、体质量,计算体质量指数(body mass index, BMI)。根据基线BMI将所有老年研究对象分为5组:BMI<18.5 kg/m^(2)组,BMI 18.5~22.9 kg/m^(2)组,23.0~24.9 kg/m^(2)组,25.0~29.9 kg/m^(2)组和BMI≥30.0 kg/m^(2)组。调查问卷法收集既往慢性疾病史(高血压、糖尿病、脂代谢异常)。收集基线收缩压、舒张压、空腹血糖、糖化血红蛋白、总胆固醇、三酰甘油、高密度脂蛋白、低密度脂蛋白和肾小球滤过率数据。随访期间每年测量收缩压和舒张压。收缩压≥140 mmHg(1 mmHg=0.133 kPa)和(或)舒张压≥90 mmHg认定为高血压。采用Cox比例风险回归模型评估基线BMI与高血压发生风险的关系。结果 随访5年期间新发高血压2 138例。调整年龄、性别、糖代谢、脂代谢和肾小球滤过率后发现,以BMI为18.5~22.9 kg/m^(2)的老年人群为对照,BMI<18.5 kg/m^(2)组,23.0~24.9 kg/m^(2)组,25.0~29.9 kg/m^(2)组,≥30.0 kg/m^(2)组高血压发生风险的HR值分别为0.65(95%CI:0.48~0.88),1.23(95%CI:1.10~1.38),1.47(95%CI:1.32~1.63)和1.85(95%CI:1.44~2.38)。BMI每增加1.0 kg/m^(2),高血压发生风险增加7%(HR:1.07;95%CI:1.06~1.09,P<0.001)。男女分组的结果与总人群趋势一致。排除60~65岁、糖代谢异常、脂代谢异常的老年人进行敏感性分析得到的结果与主效应分析一致。结论 老年人BMI升高可明显增加高血压发生风险。为降低老年人群发生高血压的风险,建议将体质量控制在正常范围。

Objective To evaluate the relationship between body mass index(BMI) and incident hypertension in elderly people. Methods A total of 9 474 elderly subjects aged ≥ 60 years(5 337 men and 4 137 women) were recruited from Health Management Center of Ren Ji hospital in 2014 and followed up for five years. The height, body mass and BMI were measured;history of chronic diseases(hypertension, diabetes, abnormal lipid metabolism) was taken from the questionnaire;systolic blood pressure, diastolic blood pressure, fasting blood glucose, glycated hemoglobin A1 c, total cholesterol, triglyceride, low density lipoprotein cholesterol, high density lipoprotein cholesterol and estimating glomerular filtration were collected from the physical examination report. All subjects were classified into five groups based according to the BMI: <18.5 kg/m^(2),18.5-22.9 kg/m^(2),23.0-24.9 kg/m^(2),25.0-29.9 kg/m^(2) and≥30.0 kg/m^(2). Systolic blood pressure and diastolic blood pressure were annually measured during follow-up(2014—2019). Hypertension were diagnosed as systolic blood pressure≥140 mmHg and/or diastolic blood pressure≥90 mmHg. Cox proportional hazards regression model was used to analyze the association between BMI and incident hypertension. Results There were 2 138 new hypertension cases during five-year follow up. Comparing elderly people with a BMI range of 18.5-22.9 kg/m^(2)(reference), the hazards ratio for incident hypertension in 18.5-22.9 kg/m^(2), 23.0-24.9 kg/m^(2), 25.0-29.9 kg/m^(2) and ≥30.0 kg/m^(2) groups was 0.65(95%CI: 0.48-0.88),1.23(95%CI: 1.10-1.38),1.47(95%CI: 1.32-1.63) and 1.85(95%CI: 1.44-2.38) after adjusting age, sex, fasting blood glucose, glycated hemoglobin A1 c, lipid profiles, and estimating glomerular filtration. Each unit increase of BMI(=1.0 kg/m^(2)) was associated with a higher risk of 7%(HR=1.07,95%CI: 1.06-1.09, for trend P<0.001). The results of subgroup stratified by sex were consistent with the main results. Sensitivity analysis generated consistent results after excluding elderly people aged 60-65 years old, people with abnormal glucose metabolism, and those with abnormal lipid metabolism at baseline. Conclusion High BMI is associated with high risk of developing hypertension in elderly people. In order to reduce the risk of hypertension, it is recommended to control their weight in a normal and moderate range.