Systemic sclerosis and risk of bronchiectasis: A nationwide longitudinal cohort study

Backgroud: The impact of systemic sclerosis on the development of bronchiectasis is unclear. This study aimed to compare the risk of bronchiectasis between individuals with systemic sclerosis and those without using a nationwide longitudinal dataset. Methods: : Using the Korean National Health Insurance Service dataset between 2010 and 2017, we identified 4,845 individuals aged ≥ 20 years with systemic sclerosis and 24,225 without systemic sclerosis who were matched 1:5 by age and sex. They were followed up until the date of a bronchiectasis diagnosis, death, or December 31, 2019, whichever came first. Results: : During a median follow-up period of 6.0 (interquartile range, 3.2–8.7) years, 5.3% of the systemic sclerosis cohort and 1.9% of the matched cohort developed bronchiectasis, with incidence rates of 9.99 and 3.23 per 1,000 person-years, respectively. Even after adjusting for potential confounders, the risk of incident bronchiectasis was significantly higher in the systemic sclerosis cohort than in the matched cohort (adjusted hazard ratio 2.63, 95% confidence interval 2.22–3.12). The risk of incident bronchiectasis was notably higher in younger individuals ( P for interaction = 0.048) and those with coexisting connective tissue disease ( P for interaction = 0.005) compared to their counterparts. Conclusions: : The risk of incident bronchiectasis is higher in individuals with systemic sclerosis than those without. Bronchiectasis should be considered one of the pulmonary manifestations related to systemic sclerosis.