Complexity of lifetime occupation and cognitive performance in old age

Occupation is recognized as a modifiable factor related to cognitive reserve in older adults. To examine the association between levels of complexity in lifelong occupations and cognitive performance in later life. A cross-sectional study of older adult users (aged 65 or more) of a private health care plan, resident in the north zone of Rio de Janeiro City, Brazil, and participating in the Rio de Janeiro section of the Study of Fragility in Brazilian Older Adults (FIBRA-RJ). Cognitive performance scores were obtained using the Mini-Mental State Examination. The level of complexity of their work was assessed in three domains: work with data, persons and things. Associations between the complexity of work in each domain and cognitive performance were evaluated using multivariate linear regression, adjusted for socio-demographic variables and duration of occupation. A total of 624 older adults (94% of the study group) performed lifelong work activities. Among those working with data, the high complexity group had cognitive performance scores 1.08 points higher (P < 0.05) than low complexity. In work with things, scores in the intermediate complexity group were 0.53 points higher (P < 0.05) than low complexity. There was no statistically significant difference in the cognitive performance between levels of complexity of work with people. Complexity in work with data and things was associated with better cognitive performance in later life, independent of age, schooling, income and duration of occupation.