the Brazilian National Household Sample

Background: The rapid population ageing has been accompanied by a growing number of older adults experiencing chronic conditions, especially diabetes and hypertension, which are conditions associated to the decline in physical functioning. The aim of this study was to investigate changes in the strength of the association between mobility and two chronic conditions (hypertension and diabetes) in a large representative sample of Brazilian older adults over a ten year period. Methods: The data came from the Brazilian National Household Sample Survey (PNAD) of 1998, 2003 and 2008. The sample comprised 28,943 participants aged 60 years and older investigated in 1998, 35,042 in 2003 and 41,269 in 2008, totalling 105,254 older adults. The dependent variable was the physical mobility index (PMI) constructed based on the Item Response Theory (IRT) using five physical mobility indicators. The chronic conditions were self-reported and the confounders included: age, sex, schooling, ethnicity, family income, household composition, other co-morbidities and use of health services. The association between physical mobility (three different groups) and chronic conditions (hypertension and diabetes) was performed using multinomial logistic regression. Results: Over the ten year period the prevalence of hypertension increased from 44 % (1998), 49 % (2003) to 53