The contributions of first nations ethnicity, income, and delays in surgery on mortality post-fracture : a population-based analysis

Summary We examined the independent contributions of First Nations ethnicity and lower income to post-fracture mortality. A similar relative increase in mortality associated with fracture appears to translate into a larger absolute increase in post-fracture mortality for First Nations compared to non-First Nations peoples. Lower income also predicted increased mortality post-fracture.

Introduction First Nations peoples have a greater risk of mortality than non-First Nations peoples. We examined the independent contributions of First Nations ethnicity and income to mortality post-fracture, and associations with time to surgery post-hip fracture.

Methods Non-traumatic fracture cases and fracture-free controls were identified from population-based administrative data repositories for Manitoba, Canada (aged ≥50 years). Populations were retrospectively matched for sex, age (within 5 years), First Nations ethnicity, and number of comorbidities. Differences in mortality post-fracture of hip, wrist, or spine, 1996–2004 (population 1, n = 63,081), and the hip, 1987–2002(Population 2, n = 41,211) were examined using Cox proportional hazards regression to model time to death. For hip fracture, logistic regression analyses were used to model the probability of death within 30 days and 1 year.

Results Population 1: First Nations ethnicity was associated with an increased mortality risk of 30–53 % for each fracture type. Lower income was associated with an increased mortality risk of 18–26 %. Population 2: lower income predicted mortality overall (odds ratio (OR) 1.15, 95 % confidence interval (CI) 1.07–1.23) and for hip fracture cases (OR 1.18, 95%CI 1.05–1.32), as did older age, male sex, diabetes, and >5 comorbidities (all p ≤ 0.01). Higher mortality was associated with pertrochanteric fracture (OR 1.14, 95 % CI 1.03–1.27), or surgery delay of 2–3 days (OR 1.34, 95 % CI 1.18–1.52) or ≥4 days (OR 2.35, 95 % CI 2.07–2.67).

Conclusion A larger absolute increase in mortality post-fracture was observed for First Nations compared to non-First Nations peoples. Lower income and surgery delay >2 days predicted mortality post-fracture. These data have implications regarding prioritization of healthcare to ensure targeted, timely care for First Nations peoples and/or individuals with lower income.