Timing of surgery for hip fracture and in-hospital mortality: a retrospective population-based cohort study in the Spanish National Health System

A cohort of 56,500 patients of 60-years-old and over, hospitalized for hip fracture during the period 2002 to 2005 in all the public hospitals in 8 Spanish regions, were followed up using administrative databases to identify the time to surgical repair and in-hospital mortality. We used a multivariate logistic regression model to analyze the relationship between the timing of surgery (< 2 days from admission) and in-hospital mortality, controlling for several confounding factors.Early surgery was performed on 25% of the patients. In the unadjusted analysis early surgery showed an absolute difference in risk of mortality of 0.57 (from 4.42% to 3.85%). However, patients undergoing delayed surgery were older and had higher comorbidity and severity of illness. Timeliness for surgery was not found to be related to in-hospital mortality once confounding factors such as age, sex, chronic comorbidities as well as the severity of illness were controlled for in the multivariate analysis.Older age, male gender, higher chronic comorbidity and higher severity measured by the Risk Mortality Index were associated with higher mortality, but the time to surgery was not.The incidence of hip fracture in Spain is higher than 100 per 100,000 inhabitants-year, exceeding 500 per 100,000 in people aged 65 and over [1,2]. The ratio men/women ranges between 2.5 and 3 [1,2], the variation among geographical areas being smaller than for other conditions [3]. Mortality in the month following the fracture ranges from 5% to 10%, reaching 30% after a year [4-6], with another 30% of patients having a high grade of disability [4,5,7]. In-hospital mortality varies greatly between series, ranging from 3.7% [8] to 12% [9].The non-surgical repair of hip fracture is uncommon because of unacceptable outcomes [10]. A decision on the surgical modality depends on the fracture itself and patient factors like age. Whereas reduction and external fixation is a common option for young people or in trochanteric fr