Background. Long-term predictors of geriatric syndrome of frailty are unclear. Several obesity-related conditions are associated with frailty. This study examines the predictive role of midlife overweight and obesity on development of frailty more than 22 years of follow-up.

Methods. Data are from 1,119 men and women aged 30 or older without frailty at baseline participating in a population-based Mini-Finland Health Examination Survey (1978–1980) with follow-up measurement in 2000–2001. At baseline (1978–1980), body weight and height were measured. At follow-up (2000–2001), the dependent variable prefrailty was defined as the presence of one or two of five frailty indicators (shrinking, weakness, exhaustion, slowness, and low physical activity) and frailty was defined as three or more indicators.

Results. The mean age at the baseline was 43.6 (SD 9.7) years, and majority of the participants (95%) were 30–60 years old. Incidence of prefrailty was 5% and frailty 36%. Based on adjusted multinomial logistic regression, persons with overweight (body mass index 25–29.9kg/m²) and obesity (body mass index ≥ 30kg/m²) at baseline had increased risk of prefrailty (odds ratio 1.45, 95% CI 1.08, 1.96; odds ratio 2.36, 95% CI 1.41, 3.93) and frailty (odds ratio 2.49, 95% CI 1.22, 5.06; odds ratio 5.02, 95% CI 1.89, 13.33) at follow-up in comparison to normal-weight persons after adjusting for age, sex, lifestyle factors and chronic conditions.

Conclusions. Development of frailty may start already in midlife, and obesity is one of the underlying causes of frailty.