An interRAI derived frailty index predicts acute hospitalizations in older adults residing in retirement villages: A prospective cohort study.

The development of frailty tools from electronically recorded healthcare data allows frailty assessments to be routinely generated, potentially beneficial for individuals and healthcare providers. We wished to assess the predictive validity of a frailty index (FI) derived from interRAI Community Health Assessment (CHA) for outcomes in older adults residing in retirement villages (RVs), elsewhere called continuing care retirement communities. Prospective cohort study. 34 RVs across two district health boards in Auckland, Aotearoa New Zealand (NZ). 577 participants, mean age 81 years; 419 (73%) female; 410 (71%) NZ European, 147 (25%) other European, 8 Asian (1%), 7 Māori (1%), 1 Pasifika (<1%), 4 other (<1%). interRAI-CHA FI tool was used to stratify participants into fit (0-0.12), mild (>0.12-0.24), moderate (>0.24-0.36) and severe (>0.36) frail groups at baseline (the latter two grouped due to low numbers of severely frail). Primary outcome was acute hospitalization; secondary outcomes included long-term care (LTC) entry and mortality. The relationship between frailty and outcomes were explored with multivariable Cox regression, estimating hazard ratios (HRs) and 95% confidence intervals (95%CIs). Over mean follow-up of 2.5 years, 33% (69/209) of fit, 58% (152/260) mildly frail and 79% (85/108) moderate-severely frail participants at baseline had at least one acute hospitalization. Compared to the fit group, significantly increased risk of acute hospitalization were identified in mildly frail (adjusted HR = 1.88, 95%CI = 1.41-2.51, p<0.001) and moderate-severely frail (adjusted HR = 3.52, 95%CI = 2.53-4.90, p<0.001) groups. Similar increased risk in moderate-severely frail participants was seen in LTC entry (adjusted HR = 5.60 95%CI = 2.47-12.72, p<0.001) and mortality (adjusted HR = 5.06, 95%CI = 1.71-15.02, p = 0.003). The FI derived from interRAI-CHA has robust predictive validity for acute hospitalization, LTC entry and mortality. This adds to the growing literature of use of interRAI tools in this way and may assist healthcare providers with rapid identification of frailty.

Déclaration de conflit d'intérêts

Dr Dale Bramley, CEO of Waitemata District Health Board (which partly funded this project) was participating in this study as a Māori public health medicine specialist, and not related to the organisation’s part funding. Additionally Dale Bramley and Annie Tatton were employed by Waitematā District Health Board. This does not alter our adherence to PLOS ONE policies on sharing data and materials. Study sponsors had no role in the design, methods, subject recruitment, data collections, analysis, decision to publish or preparation of manuscript. The authors have no conflicts of interest to declare.