People with type 2 diabetes (T2D) are at a greater risk for hip fracture even when accounting for death as a competing risk, according to new findings published in the Journal of Bone and Mineral Research.
T2D is a risk factor for both death and hip fracture, but studies evaluating the association between T2D and hip fractures often fail to account for death as a competing risk. Thus, the risk for fracture may be overestimated. In the current study, the authors used a large population-based computerized records database to evaluate the effect of differential mortality on the association between T2D and hip fracture risk.
The cohort included 55,891 people with T2D and 103,093 matched controls. People with T2D were observed for a median of 6.4 years and controls were followed for a median of 8 years.
There was a significant association for death and hip fracture: hazard ratio (HR) 1.51 (95% CI, 1.48-1.55) and HR 1.32 (95% CI, 1.24-1.40), respectively. When accounting for death as a competing event, the association between T2D and hip fracture risk continued to be statistically significant (subhazard ratio 1.15; 95% CI, 1.09-1.21). People with T2D had a 50% increased mortality compared with controls, and after adjusting for differential survival at 5 years, they also had a 21% increased incidence of hip fractures.
The authors concluded that, “estimation of hip fracture risk without accounting for death as a competing event results in an overestimation of fracture risk,” but their results confirm that people with T2D are at higher risk for hip fracture even after accounting for death as a competing risk.
Cristian Tebé has received lecture fees and honoraria from Boehringer Ingelheim. Daniel Prieto-Alhambra has received lecture fees and honoraria from Servier, Amgen, and UCB Biopharma SRL. Adolf Diez-Perez has received lecture fees and honoraria from Amgen, Lilly, Gilead, UCB, Roche, Amgen and EchoLight. Cyrus Cooper has received lecture fees and honoraria from Amgen, Danone, Eli Lilly, GSK, Medtronic, Merck, Nestlé, Novartis, Pfizer, Roche, Servier, Shire, Takeda and UCB.
Tebé C, Martinez-Laguna D, Moreno V, et al. Differential mortality and the excess rates of hip fracture associated with type 2 diabetes: accounting for competing risks in fracture prediction matters [published online April 6, 2018]. J Bone Miner Res. doi: 10.1002/jbmr.3435