Intrinsic capacity deficits across the lifespan in a nationally representative community cohort: findings from the Queenstown study

BACKGROUND: Intrinsic capacity (IC) is central to the World Health Organization's life course approach to healthy ageing. Population-level data across the lifespan remain limited. This study aimed to assess the prevalence of IC deficits and to identify sociodemographic, clinical, and lifestyle factors associated with these deficits in a nationally representative community cohort in Singapore. METHODS: Cross-sectional survey of adults aged ≥21 years in the Queenstown Study. IC was assessed using a modified WHO ICOPE Step 1 screening approach. Sociodemographic and health data were collected. RESULTS: Among 4274 participants, 29.2 % had ≥1 IC deficit; prevalence rose stepwise with age from 10.3 % (20-39 years) to 19.1 % (40-59), 45.0 % (60-79) and 74.5 % (≥80 years). Locomotion (16.8 %) and sensory (11.4 %) deficits were most common. In multivariable analysis, IC deficits were associated with older age (OR 1.05 per year, 95 % CI 1.04-1.06, p < 0.001), female sex (OR 1.19, 95 % CI 1.01-1.40, p = 0.037), underweight (OR 1.61, 95 % CI 1.18-2.20, p = 0.003), and obesity (OR 1.36, 95 % CI 1.07-1.71, p = 0.011), frailty (OR 10.94, 95 % CI 3.57-48.14, p < 0.001), impaired instrumental ADLs (OR 3.93, 95 % CI 2.11-7.84, p < 0.001), low handgrip strength (OR 1.68, 95 % CI 1.43-1.97, p < 0.001), diabetes (OR 1.45, 95 % CI 1.12-1.87, p = 0.004), and social isolation (OR 1.23, 95 % CI 1.04-1.45, p = 0.014). Higher quality of life was protective (OR 0.84, 95 % CI 0.80-0.89, p < 0.001). CONCLUSION: IC deficits were prevalent even in midlife and linked to modifiable factors. These findings support the need for early, multidomain interventions to preserve function and promote healthy ageing across adulthood.