Characteristics of Australian cognitive super-agers using different measurement approaches

OBJECTIVES: To explore the characteristics of cognitive super-agers and determine which definition best explains variance in outcomes. METHOD: 'Super-agers', defined as (i) performance in at least one cognitive domain comparable to adults in their 30s-40s and at least average performance in other domains (SA1), (ii) superior performance for age (SA2) or (iii) no cognitive decline over time (SA3), were compared with 'typical agers' in a sample of 1611 Australian adults aged 65-106. Logistic regression was used to determine which variables best discriminated between super-agers and typical agers for each definition. Separate generalised linear models were used to determine variance in functional, physical and psychosocial outcomes. RESULTS: SA1 (n = 459) and SA2 (n = 236) had higher education and occupational complexity, less hypertension and lower depression scores; SA3 (n = 266) had higher physical activity, lower depression and hearing impairment. All cohorts had greater brain volumes and white matter integrity. Super-ageing was associated with less functional impairment (10.1-16.1%, p < 0.001). SA1 and SA2 were associated with faster walking speed (5.4-6.4%, p < 0.001) and better psychological wellbeing (5-6.5%, p = 0.001-0.003). CONCLUSION: This study demonstrates differences in factors associated with either superior cognition in older age or maintaining cognitive abilities. SA1 and SA2 were most strongly associated with positive outcomes.