[Relationship between obesity and death by multi-morbidity status in older adults in China]

Objective: To explore the relationship between obesity status and death stratified by different multi-morbidity status in older adults in China. Methods: Data for older Chinese adults aged ≥65 years were from Chinese Longitudinal Healthy Longevity Survey (CLHLS). Multi-morbidity patterns based on 13 chronic conditions were explored using exploratory factor analysis. Cox models were used to examine relationships between obesity status and death stratified by disease count and multi-morbidity patterns at baseline, respectively. Besides, obesity status was defined by baseline body mass index and waist circumference. Results: A total of 6 272 participants were included in the analyses. Multi-morbidity including cardio-metabolic, sensory perception and other patterns were identified. For those without any chronic condition, compared with those without central obesity, central obesity was associated with a higher risk for death (HR=1.66, 95%CI:1.04-2.66). For those only with one chronic condition, compared with normal weight, underweight was associated with a higher risk for death (HR=1.41, 95%CI: 1.10-1.80). For those with multi-morbidity, compared with normal weight, underweight increased the risk for death (HR=1.19, 95%CI:1.05-1.34). Compared with those without central obesity, central obesity decreased the risk for death (HR=0.88, 95%CI:0.78-0.99). Conclusions: Relationships between obesity status and death varied by multi-morbidity status in older adults in China. Underweight and non-central obesity were associated with increased risks for death in older adults with only one chronic disease or multi-morbidity. Therefore, it is necessary to pay attention to multi-morbidity status in the management of obesity in older adults and provide effective targeted body weight management plan.