Longitudinal Patterns of Postfracture Outpatient Physical Therapy and Occupational Therapy Use and Its Association With 3-Year Mortality Among Adults With Cerebral Palsy

Abstract Objective Fragility fractures are common among adults with cerebral palsy (CP), but clinical rehabilitation use after fracture and its effect on long-term health outcomes have not been sufficiently studied. The objectives of this study were to identify patterns of the use of physical therapy, occupational therapy, or both in the 6-month postfracture period and the association with 3-year mortality in adults with CP. Methods This retrospective cohort study included adults who were ≥18 years old, had CP, and had sustained an incident fragility fracture between January 1, 2014, and December 31, 2016, as identified from a random 20% Medicare fee-for-service dataset. Six-month outpatient physical therapy or occupational therapy use patterns after fracture were identified using group-based trajectory modeling. Cox regression determined the association between physical therapy or occupational therapy use trajectory patterns and mortality from 6 months to 3 years after fracture, adjusting for confounders. Effect modification by key characteristics was tested, including age, sex, and the modified Whitney Comorbidity Index (mWCI), which is a CP-specific comorbidity index that better captures overall medical complexity. Results Of the 2429 participants included, the majority (73.2%) were characterized as having little to no probability of physical therapy or occupational therapy use, whereas 16.0 and 10.7% were characterized as having early initiation and later initiation, respectively. Compared to the mortality rate for the little to no physical therapy or occupational therapy group, the mortality rates were 26% lower for the early physical therapy or occupational therapy initiation group (hazard ratio [HR] = 0.74; 95% CI = 0.55–1.00) and were 20% lower for the later initiation group (HR = 0.80; 95% CI = 0.57–1.12). There was effect modification by the mWCI. The mortality rate was lower when the early initiation and later initiation groups were compared to the little to no initiation group across all mWCI values examined (median and interquartile range), but the effect was stronger (ie, lower mortality rate) for lower mWCI values for both early initiation and later initiation groups. Conclusion Most adults with CP underutilize outpatient physical therapy or occupational therapy services within 6 months postfracture. Early or later initiation versus little to no physical therapy or occupational therapy use was associated with a lower HR of mortality, althoug