title: Modifying Effect of Body Mass Index on Survival in Elderly Type 2 Diabetic Patients: Hong Kong Diabetes Registry.
abstract: OBJECTIVE
  There are nonlinear risk associations of body mass index (BMI) with mortality in type 2 diabetes (T2D) and elderly populations although similar information in elderly individuals with T2D are lacking.
  
  
  METHODS
  We analyzed prospective data for 3186 Chinese patients with T2D with age 65 years or older. Baseline demographic data, risk factors, complications, and all-cause mortality were captured from the Hong Kong Diabetes Registry and the Hong Kong Hospital Authority Clinical Management System.
  
  
  RESULTS
  Over a median follow-up period of 6.0 years (medium-term), 816 (25.6%) deaths occurred and at 9.4 years (long-term), 1557 (48.9%) patients had died. Men were more likely to die than women with increased mortality rate with increasing age (morality rates of men with normal BMI at 9-year follow-up in the 65 to 69, 70 to 74, and 75 years or older age groups were 41.8, 70.3, and 101.4 per 1000 person-years, whereas that for women were 35.5, 50.4, and 78.8 respectively). Within each age group, high BMI was associated with increased survival, especially in the 75 years and older age group and with prolonged follow-up period. Using Cox regression analysis, after adjustment for confounders, high BMI (≥ 25.0 kg/m(2)) was associated with reduced risk of death in all subgroups, reaching significance in men in the older age groups at 9-year follow-up (for men 70 to 74 years old, hazard ratio [HR] of mortality was 0.67, 95% confidence interval [CI] 0.48-0.95, for those ≥ 75, HR was 0.62, 95% CI 0.44-0.89) compared with 18.5 to 22.9 kg/m(2) as referent.
  
  
  CONCLUSIONS
  In Chinese elderly patients with T2D, high BMI protected against mortality, calling for more attention to people with low BMI who might have unmet clinical needs.
authors.affiliation: Department of Medicine and Therapeutics, Prince of Wales Hospital, the Chinese University of Hong Kong, Hong Kong SAR.
authors.forename: Kitty K T
authors.initials: KK
authors.lastname: Cheung
authors.affiliation: Department of Medicine and Therapeutics, Prince of Wales Hospital, the Chinese University of Hong Kong, Hong Kong SAR.
authors.forename: Guozhi
authors.initials: G
authors.lastname: Jiang
authors.affiliation: Department of Medicine and Therapeutics, Prince of Wales Hospital, the Chinese University of Hong Kong, Hong Kong SAR.
authors.forename: Jenny S W
authors.initials: JS
authors.lastname: Lee
authors.affiliation: Department of Medicine and Therapeutics, Prince of Wales Hospital, the Chinese University of Hong Kong, Hong Kong SAR. Electronic address: andrealuk@cuhk.edu.hk.
authors.forename: Andrea O Y
authors.initials: AO
authors.lastname: Luk
authors.affiliation: Department of Medicine and Therapeutics, Prince of Wales Hospital, the Chinese University of Hong Kong, Hong Kong SAR.
authors.forename: Alice P S
authors.initials: AP
authors.lastname: Kong
authors.affiliation: Department of Medicine and Therapeutics, Prince of Wales Hospital, the Chinese University of Hong Kong, Hong Kong SAR.
authors.forename: Risa
authors.initials: R
authors.lastname: Ozaki
authors.affiliation: Department of Medicine and Therapeutics, Prince of Wales Hospital, the Chinese University of Hong Kong, Hong Kong SAR.
authors.forename: Rose Z W
authors.initials: RZ
authors.lastname: Ting
authors.affiliation: Department of Medicine and Therapeutics, Prince of Wales Hospital, the Chinese University of Hong Kong, Hong Kong SAR.
authors.forename: Ronald C W
authors.initials: RC
authors.lastname: Ma
authors.affiliation: Department of Medicine and Therapeutics, Prince of Wales Hospital, the Chinese University of Hong Kong, Hong Kong SAR.
authors.forename: Francis C C
authors.initials: FC
authors.lastname: Chow
authors.affiliation: Department of Medicine and Therapeutics, Prince of Wales Hospital, the Chinese University of Hong Kong, Hong Kong SAR.
authors.forename: Juliana C N
authors.initials: JC
authors.lastname: Chan
authors.affiliation: Department of Medicine and Therapeutics, Prince of Wales Hospital, the Chinese University of Hong Kong, Hong Kong SAR.
authors.forename: Wing-Yee
authors.initials: WY
authors.lastname: So
mesh_terms: D000368:Aged; D015992:Body Mass Index; D003924:Diabetes Mellitus, Type 2; D005260:Female; D006723:Hong Kong / Q000453:epidemiology; D006801:Humans; D008297:Male; D009026:Mortality / Q000639:trends*; D011446:Prospective Studies; D012042:Registries; D016019:Survival Analysis
keywords: Type 2 diabetes; body mass index; survival