Elevated Rates and Earlier Onset of Nonpulmonary Comorbidities in Adults with Cystic Fibrosis: A Population-based Study

Abstract Rationale People with cystic fibrosis (pwCF) are living longer with increasing comorbidities. Objectives To estimate the rate of emerging nonpulmonary comorbidities in adults with cystic fibrosis (CF) and to compare these rates with the non-CF population. Methods This is a population-based cohort study of adults using Canadian Cystic Fibrosis Registry data linked with health administrative databases in Ontario. Cases of cardiovascular disease (CVD) and symptomatic kidney stones were identified using diagnostic and procedural codes. Chronic kidney disease (CKD) was defined as estimated glomerular filtration rate 60 ml/min/1.73 m2. Cancer cases were obtained using the Ontario Cancer Registry. Poisson regression was used to estimate the rates per 1,000 person-years of follow-up. Results The age- and sex-adjusted rates of CVD, CKD, kidney stones, and cancer per 1,000 person-years in the non–lung transplantation cohort were 24.5 (95% confidence interval CI, 21.5–28.0), 3.7 (95% CI, 2.7–5.2), 7.4 (95% CI, 6.1–9.0), and 5.8 (95% CI, 4.5–7.6) respectively. pwCF who underwent lung transplantation had higher rates of all four conditions, and cancer and CKD occurred earlier compared with the nontransplantation cohort. When comparing the CF and non-CF populations, pwCF without lung transplantation had higher age- and sex-adjusted rates of CVD (relative risk RR, 2.9 95% CI, 2.6–3.4), CKD (RR, 2.1 95% CI, 1.5–2.9), kidney stones (RR, 2.9 95% CI, 2.4–3.6), and cancer (RR, 1.9 95% CI, 1.5–2.5). These events occurred at a median age of at least 20 years earlier in the CF cohort. In the post-transplantation population, there were no significant differences in the rates of CVD, kidney stones, and cancers between pwCF and the non-CF population, but events occurred earlier in pwCF. Conclusions Nonpulmonary complications occur at a high rate and at a younger age in pwCF compared with the non-CF population, which highlights the importance of incorporating these issues in CF care models.