Equality of Treatment for Hip Fracture Irrespective of Regional Differences in Socioeconomic Status: Analysis of Nationwide Hospital Claims Data in Japan

: Despite the wide variety of international evidence on the relationship between the socioeconomic status (SES) and health outcomes, less is known about the association between SES and healthcare provider practices. We assessed whether patients with a closed hip fracture were treated differently by hospital physicians according to the SES of their residential areas in Japan. Hip fracture is a common cause of hospitalization among the elderly, but the relationship between SES and hip fracture treatment remains unknown in Japan. We employed the Diagnosis Procedure Combination (DPC) database from April 2011 to March 2014. SES of the patient's residential area was estimated using Census-derived areal deprivation index (ADI). We performed a cross-sectional study of national claims data and analyzed it using cross-classified multilevel models. We used two outcome measures: (i) whether the patient received an operation or was treated by watchful waiting; and (ii) number of waiting days until operation following admission. We identified 95,011 patients admitted to 1,050 hospitals. Of these, 85,480 patients underwent surgery. Low SES of residential areas was not correlated with the chance of undergoing surgery (P = 0.15) but was weakly correlated with longer waiting days (coefficient, 0.03; 95% confidence interval, -0.01 to 0.06; P = 0.08). The difference of waiting days between maximum (10.4) and minimum ADI (-4.0) was marginal (0.39 days). The results indicate the SES of patient's residential area does not affect the decision of surgical treatment for hip fracture and has ignorable impact on waiting days from hospital admission to surgery.