Cardiovascular disease-associated admissions in patients with Cystic Fibrosis: A 7-Year U.S. National Inpatient Sample Analysis.

BACKGROUND

As survival improves for people with cystic fibrosis (PwCF) in the era of CFTR modulators, cardiovascular (CV) diseases are emerging as clinically important comorbidities. Beyond age-related risks, mechanistic pathways such as systemic inflammation, chronic hypoxia, CF-related diabetes, and CFTR-related endothelial dysfunction may contribute to CV injury. However, national-level data on CV outcomes in PwCF remain limited.

OBJECTIVES

We hypothesized that primary cardiac admissions in PwCF are increasing over time and associated with worse in-hospital outcomes compared to non-cardiac admissions.

METHODS

We retrospectively analyzed adult (≥18 years) PwCF hospitalizations in the U.S. National Inpatient Sample (2016-2022). Primary cardiac admissions were defined by a principal diagnosis of atrial fibrillation (AF), heart failure (HF), or myocardial infarction (MI) using ICD-10 codes. Outcomes included in-hospital mortality, length of stay (LOS), charges, and discharge disposition. Temporal trends in cardiac admissions were modeled using negative binomial regression with an offset for total CF hospitalizations; Joinpoint regression was performed as a complementary method. Descriptive statistics and multivariable regression models adjusted for age, sex, and race were used. A p-value <0.05 was considered statistically significant.

RESULTS

Among 121,290 PwCF hospitalizations, 520 (0.43%) were for cardiac causes. PwCF with cardiac admissions were older (median 62 vs. 29 years, p < 0.001) and had more traditional CV comorbidities. Cardiac admission rates increased by 16.4% per year from 2016 to 2022 (IRR 1.16 [1.04-1.29], p = 0.009) in negative binomial regression. Joinpoint regression detected no significant inflection points and estimated a non-significant APC of 16.4% per year (95% CI 10.9-57.4, p = 0.214). Unadjusted mortality was higher for cardiac vs. non-cardiac admissions (OR 3.70, 95% CI 1.61-8.53, p = 0.002), but not significant after adjustment (OR 1.36, 95% CI 0.55-3.34, p = 0.468).

CONCLUSION

Our findings indicated higher in-hospital mortality among PwCF admitted for cardiac causes, and more discharge to nursing facilities among PwCF admitted for cardiac causes. There is a need for greater CV screening, and geriatric care in PwCF.