Inflammatory markers and physical performance in middle-aged and older people in Indonesia

Objectives: to examine the association between C-reactive protein (CRP) and the activities of daily living (ADL) among middle-aged (40-54 years old) and older (55-96 years old) people in Indonesia. Data: data from a population-based sample, the Indonesia Family Life Survey (IFLS) 2007, were analysed. The data consist of 1,702 respondents of middle age (40-54 years old) and 2,017 older respondents who had completed information on ADL and CRP. Methods: CRP concentrations in Dried Blood Spot (DBS) specimens were measured, using the validated enzyme-linked immunosorbent assay (ELISA) method. Thirteen items of ADL were used to measure physical performance. A three-level linear model was applied to take advantage of the nested structure of data at the individual level within the household and community levels. Results: high levels of CRP were significantly associated with lower ADL for middle-aged and older people (P < 0.001). The model was adjusted for co-morbid conditions, health risk factors, medications, depressive symptoms and sociodemographic characteristics. Conclusion: the significant association between the high level of CRP and lower ADL among older people in Indonesia is in line with earlier studies in the context of developed countries. This study provides an extension in which the significant association was also found in middle-aged people (40-54 years old).