Is bigger always better? A nationwide study of hip fracture unit volume, 30-day mortality, quality of in-hospital care, and length of hospital stay.

BACKGROUND: Higher patient volume has been linked with better clinical outcomes for a range of surgical procedures; however, little is known about the impact of volume on quality of care and clinical outcome among patients with hip fracture.
OBJECTIVES: To examine the association between hip fracture patient volume and 30-day mortality, quality of in-hospital care, time to surgery, and length of hospital stay, respectively.
DESIGN: Population-based follow-up study.
SUBJECTS: Using prospectively collected data from the Danish Multidisciplinary Hip Fracture Registry, we identified 12,065 patients 65 years and older who were admitted with a hip fracture between March 1, 2010 and November 30, 2011. MEASURES: Patient volume was divided into 3 groups; ≤ 151 hip fracture admissions per year, 152-350, and ≥ 351 admissions per year based on the distribution of the hospitals and to ensure a reasonable proportion of hospitals in each category. Data were analyzed using regression techniques while controlling for potential confounders.
RESULTS: Admission to high-volume units was associated with higher 30-day mortality [adjusted odds ratio (OR)=1.37 (95% confidence interval (CI), 1.14-1.64)] and a longer length of hospital stay (adjusted relative time=1.25 (95% CI, 1.02-1.52)]. Furthermore, patients had lower odds for being mobilized within 24 hours postoperatively and for receiving basic mobility assessment and a postdischarge rehabilitation program. Time to surgery was nonsignificantly increased [adjusted relative time=1.25 (95% CI, 0.99-1.58)].
CONCLUSIONS: Patients admitted to high-volume hip fracture units had higher mortality rates, received a lower quality of in-hospital care, and had longer length of hospital stay.