Mortality after osteoporotic hip fracture: incidence, trends, and associated factors.

Background: It is known that mortality after hip fracture increases compared to the general population; the trend in mortality is a controversial issue. The objective of this study is to examine incidence, trends, and factors associated with mortality in patients with osteoporotic hip fractures.

Methods: This is a retrospective cohort study that uses the Registry for Hospital Discharges of the National Health System of our hospital. Patients older than 45 having an osteoporotic hip fracture between 1999 and 2015 were identified. Demographic data and comorbidities were obtained. A survival analysis was performed (Cox regression and Kaplan-Meier). Incidence rate, standardized death rate (SDR), trend (Poisson regression), and risk (hazard ratio) were calculated.

Results: During 1999-2015, in our hospital, there were a total of 3992 patients admitted due to osteoporotic hip fracture. Out of these 3992 patients, 3109 patients (77.9%) were women with an average age of 84.47 years (SD 8.45) and 803 (22.1%) were men with an average age of 81.64 years (SD 10.08). The cumulative incidence of mortality was 69.38%. The cumulative mortality rate for 12 months was 33%. The annual mortality was 144.9/1000 patients/year. The 1-year mortality rate increased significantly by 2% per year (IRR 1.020, CI95% 1.008-1.033). The median overall survival was 886 days (CI95% 836-951). The probability of mortality density for a period of 10 years following a hip fracture was 16% for women and 25% for men (first 90 days). The SDR was 8.3 (CI95% 7.98-8.59). Variables that showed statistically significant association with mortality were aged over 75, masculine, institutionalization, mild to severe liver disease, chronic kidney disease, COPD, dementia, heart failure, diabetes, the Charlson Index > 2 , presence of vision disorders and hearing impairment, incontinence, and Downton scale.

Conclusions: For the last 17 years, an increase of mortality for patients with hip fracture and a higher mortality rate in men than in women were observed. Institutionalization combined with comorbidities is associated with a higher mortality.