The study reported elevated adjusted rates for four non-pulmonary complications in those with vs. without cystic fibrosis (CF) without a lung transplant.

Adults with vs. without cystic fibrosis and no lung transplant have higher rates of cardiovascular disease, chronic kidney disease, kidney stones and cancer, according to results published in Annals of the American Thoracic Society.

Further, each of these complications happened at a younger age in those with cystic fibrosis (CF), according to researchers.

"This study has clinical implications highlighting the need for CF care models to identify and address these emerging non-pulmonary comorbidities early to improve care for [people with] CF," Rigya Arya, MD, of the division of respirology at the University of Toronto, and colleagues wrote.

In a population-based cohort study, Arya and colleagues evaluated adults in the Canadian CF Registry linked with health administrative databases in Ontario to uncover how prevalent cardiovascular disease (CVD), symptomatic kidney stones, chronic kidney disease (CKD; estimated glomerular filtration rate < 60 mL/minute/1.73m) and cancer each are among those with vs. without CF and if these complications happen at a younger age in those with CF.

The population with CF was divided into two groups: those who received a lung transplant (n = 208; 49% women) and those who did not receive a lung transplant (n = 1,435; 45.2% women). The study placed the CF transplant group against adults without CF who received a transplant (n = 1,265) and the CF non-transplant group against adults without CF and without a transplant (n = 16,435,600).

Of the four non-pulmonary comorbidities assessed, researchers found that CVD had the highest age- and sex-adjusted rate among adults with CF who did not receive a lung transplant at 24.5 per 1,000 person-years via Poisson regression. Kidney stones had the second highest age- and sex-adjusted rate per 1,000 person-years in this population (7.4), followed by cancer (5.8) and CKD (3.7).

Each of these rates were larger among adults with CF who received a lung transplant, according to the study. Per 1,000 person-years, the age- and sex-adjusted rate of CVD was 115.3, the rate of kidney stones was 14.2, the rate of cancer was 35.9 and the rate of CKD was 631.4.

When examining the median age at which patients developed these complications, researchers observed that the transplant vs. non-transplant group was younger at cancer diagnosis (37 years vs. 47 years) and at CKD diagnosis (32 years vs. 37 years).

Switching to assessing adults with vs. without CF who did not receive a lung transplant, the study reported elevated age- and sex-adjusted rates in the set of patients with CF for CVD (24.5 vs. 8.4 per 1,000 person-years), kidney stones (7.4 vs. 2.5 per 1,000 person-years), cancer (5.8 vs. 3 per 1,000 person-years) and CKD (3.7 vs. 1.8 per 1,000 person-years).

Researchers also noted that those with vs. without CF had an increased relative risk for each complication: CVD (RR = 2.94; 95% CI, 2.57-3.35), kidney stones (RR = 2.93; 95% CI, 2.41-3.57), CKD (RR = 2.08; 95% CI, 1.48-2.93) and cancer (RR = 1.92; 95% CI, 1.48-2.49).

Adults with CF without a lung transplant also experienced these complications at a younger age than adults without CF, according to the study. Among those with CF, the median age was 33 years (vs. 65 years in those without CF) for CVD, 37 years (vs. 76 years) for CKD, 31 years (vs. 51 years) for kidney stones and 47 years (vs. 67 years) for cancer.

In contrast, researchers found that the rates of CVD, kidney stones and cancer among those with CF and a lung transplant were similar to the rates among those without CF. The only complication with a heightened rate and relative risk in those with vs. without CF was CKD (age- and sex-adjusted rate, 631.4 vs. 365.9 per 1,000 person-years; RR = 1.73; 95% CI, 1.33-2.24).

Despite the lack of a significant difference in three of the four rates, those with CF and a lung transplant had each of the four complications at an earlier median age than those without CF: CVD (35 years vs. 63 years), CKD (32 years vs. 63 years), kidney stones (32 years vs. 63 years) and cancer (37 years vs. 67 years).

"This study provides baseline data prior to widespread use of CFTR modulator therapy," Arya and colleagues wrote. "Going forward, it will be important for national CF databases to track these outcomes proactively to understand the effect of modulator therapy on emerging complications."