AimTo verify the probability of maintaining functional capacity in basic activities of daily living and identify the prognostic factors of functional decline in institutionalized older adults.MethodsA longitudinal study is presented herein, with 5 waves every 6 months, throughout 2 years (2013–2015), conducted with individuals ≥60 years old in 10 nursing homes in the city of Natal-RN (Brazil). Functional capacity was assessed by the items ‘eating’, ‘personal hygiene’, ‘dressing’, ‘bathing’, ‘transferring’, ‘toileting’ and ‘walking’, through a 5-item Likert scale. Sociodemographic, institution-related and health-related variables were considered to establish the baseline. Time dependent variables included continence decline, cognitive decline, increase in the number of medication, and incidences of falls, hospitalizations and fractures. The actuarial method, the log-rank test and Cox's regression were applied as statistical methods.ResultsThe cumulative probability of functional maintenance was 78.2% (CI 95%: 72.8–82.7%), 65.1% (CI 95%: 58.9–70.5%), 53.5% (CI 95%: 47.2–59.5%) and 44.0% (CI 95%: 37.7–50.2%) at 6, 12, 18 and 24 months, respectively. Predicting factors for functional decline were: severe cognitive impairment (HR = 1.96; p = 0.001), continence decline (HR = 1.85; p = 0.002) and incidence of hospitalizations (HR = 1.62; p = 0.020), adjusted by the incidence of depression, age, education level, presence of chronic diseases and low weight.ConclusionsThe cumulative probability of maintaining functional capacity in institutionalized older adults was only 44% at the 2-year follow-up. Prognostic factors for functional decline included severe cognitive impairment, continence decline and incidence of hospitalizations.