Postoperative admission to a dedicated geriatric unit decreases mortality in elderly patients with hip fracture

Abstract

Background: Elderly patients with hip fracture have a 5 to 8 fold increased risk of death during the months following surgery. We tested the hypothesis that early geriatric management of these patients focused on co-morbidities and rehabilitation improved long term mortality.

Methods and findings: In a cohort study over a 6 year period, we compared patients aged >70 years with hip fracture admitted to orthopedic versus geriatric departments in a time series analysis corresponding to the creation of a dedicated geriatric unit. Co-morbidities were assessed using the Cumulative Illness Rating Scale (CIRS). Each cohort was compared to matched cohorts extracted from a national registry (n = 51,275) to validate the observed results. Main outcome measure was 6-month mortality. We included 131 patients in the orthopedic cohort and 203 in the geriatric cohort. Co-morbidities were more frequent in the geriatric cohort (median CIRS: 8 vs 5, P<0.001). In the geriatric cohort, the proportion of patients who never walked again decreased (6% versus 22%, P<0.001). At 6 months, re-admission (14% versus 29%, P = 0.007) and mortality (15% versus 24%, P = 0.04) were decreased. When co-morbidities were taken into account, the risk ratio of death at 6 months was reduced (0.43, 95%CI 0.25 to 0.73, P = 0.002). Using matched cohorts, the average treatment effects on the treated associated to early geriatric management indicated a reduction in hospital mortality (-63%; 95% CI: -92% to -6%, P = 0.006).

Conclusions: Early admission to a dedicated geriatric unit improved 6-month mortality and morbidity in elderly patients with hip fracture.

Figure 1. Transfers and allocation of patients.

Evolution of transfers out of the hospital (n = 392) and allocation to the orthopedic (n = 131) and geriatric (n = 203) cohorts during the study period. There were only 4 months (September to December) in 2005 and 3 months (January to March) in 2012.

Figure 2. Study flow chart.

Figure 3. Survival curves for mortality, re-hospitalization, and re-fracture.

Survival curves for mortality, re-hospitalization, and re-fracture for patients in the orthopedic (solid lines) and geriatric (dotted line) cohorts. Survival is non-adjusted (panels A, C, and E) and adjusted (panels B, D, and F) for age, sex and Cumulative Illness Rating Scale (CIRS) calculated with a Cox regression analysis. For re-hospitalization and re-fracture, death was considered as a censored observation. P values refer to log-rank test.

Figure 4. Survival curves for in-hospital mortality.

Survival curves for in-hospital mortality in the geriatric (Panel A) and orthopedic (Panel B) cohorts, and their respective matched cohorts from the national registry. P values refer to log-rank test.