Risk factors for mortality after hip fracture surgery in Japan using the National Database of Health Insurance Claims and Specific Health Checkups of Japan

Summary We investigated the risk factors for mortality of hip fracture in the elderly using the National Database of Health Insurance Claims in Japan, and survival was significantly related to sex, age, fracture type, surgical procedure, delayed operative date, comorbidities, blood transfusions, and pulmonary embolism. Purpose Hip fracture is the most common fracture in the elderly and is known to have a high mortality rate. In Japan, to the best of our knowledge, no studies have reported on mortality risk factors for hip fracture using nationwide registry databases. This study aimed to determine the number of occurrences of hip fracture and factors that increase mortality using the National Database of Health Insurance Claims and Specific Health Checkups of Japan. Methods This study included extracted data from patients who were hospitalized and underwent surgical treatment for hip fracture between 2013 and 2021, using a nationwide health insurance claims database in Japan. Patient characteristics, such as sex, age, fracture type, surgical procedure, delayed operative date, comorbidities, blood transfusions, and pulmonary embolism, were tabulated to obtain 1-year and in-hospital mortality rates. Results Both 1-year and in-patient survival were significantly lower in men, older patients, patients who underwent surgery after 3 days of admission, and patients with trochanteric and subtrochanteric fractures, internal fixation, more preoperative comorbidities, blood transfusions, and pulmonary embolism. Conclusions Survival was significantly related to sex, age, fracture type, surgical procedure, delayed operative date, comorbidities, blood transfusions, and pulmonary embolism. As the number of male patients with hip fracture will increase with the aging of society, medical staff must provide sufficient information before surgery to avoid postoperative mortality.