title: Relationship between body mass index reference and all-cause mortality: evidence from a large cohort of Thai adults.
abstract: We investigate variation in body mass index (BMI) reference and 5-year all-cause mortality using data from 87151 adult Open University students nationwide. Analyses focused on BMI reference bands: "normal" (≥18.5 to <23), "lower normal" (≥18.5 to <20.75), "upper normal" (≥20.75 to <23), and "narrow Western normal" (≥23 to <25). We report hazard ratios (HR) and 95% Confidence Intervals adjusting for covariates. Compared to lower normal, adults aged 35-65 years who were obese (BMI ≥ 30) were twice as likely to die during the follow-up (HR 2.37; 1.01-5.70). For the same group, when using narrow Western normal as the reference, the results were similar (HR 3.02; 1.26-7.22). However, different combinations of BMI exposure and reference band produce quite different results. Older age persons belonging to Asian overweight BMI category (≥23 to <25) were relatively protected from mortality (HR 0.57; 0.34-0.96 and HR 0.49; 0.28-0.84) when assessed using normal (≥18.5 to <23) and upper normal (≥20.75 to <23) as reference bands. Use of different "normal" reference produced varying mortality relationships in a large cohort of Thai adults. Caution is needed when interpreting BMI-mortality data.
authors.affiliation: National Centre for Epidemiology and Population Health, Research School of Population Health, College of Medicine, Biology and Environment, The Australian National University, Building 62, Mills Road, Acton, Canberra, ACT 2601, Australia.
authors.forename: Vasoontara
authors.identifier: 0000-0001-9101-4704
authors.initials: V
authors.lastname: Yiengprugsawan
authors.affiliation: National Centre for Epidemiology and Population Health, Research School of Population Health, College of Medicine, Biology and Environment, The Australian National University, Building 62, Mills Road, Acton, Canberra, ACT 2601, Australia.
authors.forename: Cathy
authors.initials: C
authors.lastname: Banwell
authors.affiliation: National Centre for Epidemiology and Population Health, Research School of Population Health, College of Medicine, Biology and Environment, The Australian National University, Building 62, Mills Road, Acton, Canberra, ACT 2601, Australia.
authors.forename: Jiaying
authors.initials: J
authors.lastname: Zhao
authors.affiliation: National Centre for Epidemiology and Population Health, Research School of Population Health, College of Medicine, Biology and Environment, The Australian National University, Building 62, Mills Road, Acton, Canberra, ACT 2601, Australia ; School of Human Ecology, Sukhothai Thammathirat Open University, Nonthaburi 11120, Thailand.
authors.forename: Sam-ang
authors.initials: SA
authors.lastname: Seubsman
authors.affiliation: National Centre for Epidemiology and Population Health, Research School of Population Health, College of Medicine, Biology and Environment, The Australian National University, Building 62, Mills Road, Acton, Canberra, ACT 2601, Australia.
authors.forename: Adrian C
authors.initials: AC
authors.lastname: Sleigh
mesh_terms: D000328:Adult; D044466:Asian People; D001823:Body Composition; D015992:Body Mass Index; D002423:Cause of Death; D015331:Cohort Studies; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D009765:Obesity / Q000401:mortality*; D016016:Proportional Hazards Models; D012307:Risk Factors; D016019:Survival Analysis; D013851:Thinness / Q000401:mortality*