Association between pre-operative complications, comorbidities, and in-hospital mortality in a hip fracture cohort: a register study in a tertiary hospital in Brazil

Abstract

Purpose: The incidence of hip fractures is increasing exponentially due to an aging Brazilian population. Older people had significant comorbidities which increases the risk of post-operative mortality. Our purpose was to examine the association between pre-operative infections and comorbidities on the risk of post-operative in-hospital mortality after proximal femur fracture surgery's, beyond that, to evaluate the association between comorbidities and time to surgery.

Methods: This is a population-based cohort retrospective study, using medical records of all six year consecutive surgical procedures for correction of hip fracture in a tertiary teaching Hospital in Brazil. The exclusion criteria aimed to exclusively allocate patients who had their first hip fracture secondary to low-energy trauma. Multivariate logistical regression was performed and receiver operating characteristic (ROC) curve with area under curve (AUC) to evaluate the sensitivity and specificity of the model. p-value < 0.05 was considered significant.

Results: Final sample was composed by 856 consecutive patients with 81 years of median and 164 patients were excluded. The median length of hospital say was five days with - l mortality at 3.6%. Significant variables for increased mortality included the presence of pre-operative infection (odds ratio (OR): 3.9(1.12-8.54), chronic obstructive pulmonary disease (COPD) (OR: 3.83(1.36-10.82)), and systemic arterial hypertension (SAH) (OR: 4.1(1.18-14.25)). Development of pre-operative infection was associated with a delay to surgery (OR: 1.1 (1.08-1.13)).

Conclusions: In older people with proximal femur fracture, the presence of pre-operative infection, COPD and SAH were the strongest risk factor for post-operative in-hospital mortality. Pre-operative infection was associated with statistically significant delay to surgery.

Keywords: Chronic obstructive pulmonary disease; Comorbidities; Hip fracture; Risk factors; Systemic arterial hypertension.