Risk of post-fracture pneumonia and its association with cardiovascular events and mortality in adults with intellectual disabilities.

Objective: Fragility fractures are associated with an increased risk of pneumonia, which is a leading cause of death in adults with intellectual disabilities; however, the timing and complications of post-fracture pneumonia are underinvestigated. The objectives of this study were to determine the 30-day pneumonia rate post-fracture and the association of post-fracture pneumonia with mortality and cardiovascular events among adults with intellectual disabilities. Methods: This retrospective cohort study was conducted using Medicare and commercial claims from 01 January 2011 to 31 December 2016. Incidence of pneumonia 30 days after a fragility fracture among adults ≥18 years old with intellectual disabilities (Fx cohort) was compared to the incidence among matched adults with intellectual disabilities without fractures (w/oFx cohort) and the general population of patients with an incident fragility fracture (GP+Fx). For the Fx cohort, Cox regression was used to examine the adjusted association of time-varying pneumonia (within 30 days post-fracture) with mortality and incidence of cardiovascular events 0-30, 31-365, and 366-730 days post-fracture. Results: There was a high-early rate of pneumonia within 30 days post-fracture for young, middle-aged, and elderly adults with intellectual disabilities (n = 6,183); this rate was 2.2- to 6.1-fold higher than the rate among the w/oFx (n = 12,366) and GP+Fx (n = 363,995) cohorts (all P < 0.05). For the Fx cohort, post-fracture 30-day incidence of pneumonia was associated with an increased 30-day rate of mortality (adjusted HR [aHR] = 5.19; 95% confidence interval [CI] = 3.68-7.32), heart failure (aHR = 2.96; 95% CI = 1.92-4.56), and cerebrovascular disease (aHF = 1.48; 95% CI = 0.93-2.35; P = 0.098), with sustained effects to 1 year for heart failure (aHR = 1.61; 95% CI = 1.19-2.17) and 2 years for mortality (aHR = 1.39; 95% CI = 1.06-1.83), and without evidence of effect modification by age. Discussion: Adults with intellectual disabilities are vulnerable to post-fracture pneumonia within 30 days, and complications arising from this, across the adult lifespan, and not only during the elderly years.