Korda R J, Liu B, Clements M S, Bauman A E, Jorm L R, Bambrick H J, Banks E
National Centre for Epidemiology and Population Health, The Australian National University, Canberra, Australian Capital Territory, Australia; Australian Centre for Economic Research on Health, The Australian National University, Canberra, Australian Capital Territory, Australia.
Int J Obes (Lond). 2013 Jun;37(6):790-9. doi: 10.1038/ijo.2012.155.
To quantify the risk of hospital admission in relation to fine increments in body mass index (BMI).
DESIGN, SETTING, AND PARTICIPANTS: Population-based prospective cohort study of 246,361 individuals aged greater than or equal to 45 years, from New South Wales, Australia, recruited from 2006-2009. Self-reported data on BMI and potential confounding/mediating factors were linked to hospital admission and death data.
Cox-models were used to estimate the relative risk (RR) of incident all-cause and diagnosis-specific hospital admission (excluding same day) in relation to BMI.
There were 61,583 incident hospitalisations over 479,769 person-years (py) of observation. In men, hospitalisation rates were lowest for BMI 20-<25 kg m(-2) (age-standardised rate: 120/1000 py) and in women for BMI 18.5-<25 kg m(-2) (102/1000 py); above these levels, rates increased steadily with increasing BMI; rates were 203 and 183/1000 py, for men and women with BMI 35-50 kg m(-2), respectively. This pattern was observed regardless of baseline health status, smoking status and physical activity levels. After adjustment, the RRs (95% confidence interval) per 1 kg m(-2) increase in BMI from ≥ 20 kg m(-2) were 1.04(1.03-1.04) for men and 1.04(1.04-1.05) for women aged 45-64; corresponding RRs for ages 65-79 were 1.03(1.02-1.03) and 1.03(1.03-1.04); and for ages ≥ 80 years, 1.01(1.00-1.01) and 1.01(1.01-1.02). Hospitalisation risks were elevated for a large range of diagnoses, including a number of circulatory, digestive, musculoskeletal and respiratory diseases, while being protective for just two-fracture and hernia.
Above normal BMI, the RR of hospitalisation increases with even small increases in BMI, less so in the elderly. Even a small downward shift in BMI, among those who are overweight not just those who are obese, could result in a substantial reduction in the risk of hospitalisation.
量化与体重指数（BMI）细微增加相关的住院风险。
设计、背景和参与者：基于人群的前瞻性队列研究，纳入了2006年至2009年从澳大利亚新南威尔士州招募的246,361名年龄大于或等于45岁的个体。自我报告的BMI及潜在混杂/中介因素数据与住院和死亡数据相关联。
使用Cox模型估计与BMI相关的全因及特定诊断住院（不包括当日）的相对风险（RR）。
在479,769人年（py）的观察期内有61,583例新发住院病例。男性中，BMI为20 - <25kg/m²时住院率最低（年龄标准化率：120/1000 py），女性中BMI为18.5 - <25kg/m²时住院率最低（102/1000 py）；高于这些水平，住院率随BMI增加而稳步上升；BMI为35 - 50kg/m²的男性和女性住院率分别为203和183/1000 py。无论基线健康状况、吸烟状况和身体活动水平如何，均观察到这种模式。调整后，45 - 64岁男性和女性BMI每增加1kg/m²（从≥20kg/m²起）的RR（95%置信区间）分别为1.04(1.03 - 1.04)和1.04(1.04 - 1.05)；65 - 79岁相应的RR为1.03(1.02 - 1.03)和1.03(1.03 - 1.04)；80岁及以上为1.01(1.00 - 1.01)和1.01(1.01 - 1.02)。多种诊断的住院风险升高，包括一些循环系统、消化系统、肌肉骨骼系统和呼吸系统疾病，而仅对两种骨折和疝气有保护作用。
BMI高于正常水平时，即使BMI有小幅度增加，住院RR也会升高，在老年人中升高幅度较小。即使是超重者（不仅仅是肥胖者）BMI有小幅度下降，也可能导致住院风险大幅降低。
