Cognitive performance and functional status are the major factors predicting survival of centenarians in Poland

Background: Clinical and biochemical predictors of extreme longevity would be useful in geriatric practice but have still not been clearly defined.

Methods: To identify the best nongenetic predictors of survival in centenarians, we examined 340 individuals aged 100+ years. A detailed questionnaire was completed, and comprehensive geriatric assessment and blood analyses were performed. Survival of study participants was checked annually over the period of 10 years.

Results: In the univariate Cox proportional hazards model, a longer survival of centenarians was correlated with a higher adjusted Mini-Mental State Examination (MMSE(adj)) score (p < .000001), higher Activities of Daily Living (ADL) and adjusted Instrumental Activities of Daily Living (IADL(adj)) scores (p < .000001 and p = .00008, respectively), and younger age at the time of testing (p = .005). Blood pressure, lipid profile, and C-reactive protein and hemoglobin concentrations were not associated with survival. Multivariate analysis including age, sex, and the MMSE(adj) and ADL scores showed that both MMSE(adj) and ADL predicted survival (HR = 0.978 per each MMSE(adj) point, 95% CI: 0.964-0.993, p = .004; HR = 0.900 per each ADL point, 95% CI: 0.842-0.962, p = .002, respectively). In multivariate analysis with the ADL score substituted by the IADL(adj) score, the only predictor of survival was MMSE(adj) (HR = 0.973 per each MMSE(adj) point, 95% CI: 0.958-0.988, p = .0006).

Conclusions: Cognitive and functional performances are predictors of survival in centenarians.