Trends in prevalence and outcomes of frailty in a Swiss university hospital: a retrospective observational study

Abstract Background Frailty complicates management and worsens outcomes. We assessed the prevalence, determinants and consequences of frailty among elderly patients in a hospital setting. Design Retrospective observational study in a Swiss university hospital. Methods 22,323 patients aged ≥65 years hospitalized between January 2009 and December 2017 at the internal medicine ward were included. Frailty was defined by the Hospital Frailty Risk Score (HFRS) and patients were categorized as low (HFRS15) risk. Results Overall prevalence of intermediate and high risk of frailty was 43% and 20%, respectively; prevalence was higher in women and increased with age. Prevalence of high risk of frailty increased from 11.4% in 2009 to 31% in 2012, and decreased to 19.2% in 2017. After multivariable adjustment, frailty was associated with increased length of stay: average and (95% confidence interval) 11.9 (11.7–12.1), 15.6 (15.4–15.8) and 19.7 (19.3–20.1) days for low, intermediate and high risk, respectively, and increased likelihood of ICU stay: odds ratio (OR) and (95% CI) 1.57 (1.41–1.75) and 2.10 (1.82–2.42) for intermediate and high risk, respectively, p for trend 70,000 CHF: OR and (95% CI) 3.46 (2.79–4.29) and 10.7 (8.47–13.6) for intermediate and high risk, respectively, p for trend