Pulmonary function disparities exist and persist in Hispanic patients with cystic fibrosis: A longitudinal analysis

Abstract

Background Hispanic patients with cystic fibrosis (CF) have decreased life expectancy compared to non-Hispanic white patients. Pulmonary function is a main predictor of life expectancy in CF. Ethnic differences in pulmonary function in CF have been understudied. The objective was to compare longitudinal pulmonary function between Hispanic and non-Hispanic white patients with CF. Methods This cohort study of 15,018 6–25 years old patients in the CF Foundation Patient Registry from 2008 to 2013 compared FEV1 percent predicted and longitudinal change in FEV1 percent predicted in Hispanic to non-Hispanic white patients. We used linear mixed effects models with patient-specific slopes and intercepts, adjusting for 14 demographic and clinical variables. We did sub-analyses by CFTR class, F508del copies, and PERT use. Results Hispanic patients had lower FEV1 percent predicted (79.9%) compared with non-Hispanic white patients (85.6%); (−5.8%, 95% CI −6.7% to −4.8%, p<0.001), however, there was no difference in FEV1 decline over time. Patients on PERT had a larger difference between Hispanic and non-Hispanic white patients in FEV1 percent predicted than patients not on PERT (−6.0% vs. −4.1%, p=0.02). The ethnic difference in FEV1 percent predicted was not statistically significant between CFTR classes (Class I–III: −6.1%, Class IV–V: −5.9%, Unclassified: −5.7%, p>0.05) or between F508del copies (None: −7.6%, Heterozygotes: −5.6%, Homozygotes: −5.3%, p>0.05). Conclusions Disparities in pulmonary function exist in Hispanic patients with CF early in life and then persist without improving or worsening over time. It is valuable to investigate the factors contributing to pulmonary function in Hispanic patients with CF.

Regional variations in longitudinal pulmonary function: A comparison of Hispanic and non‐Hispanic subjects with cystic fibrosis in the United States

“…Despite Hispanic subjects having a lower pulmonary function that non‐Hispanic white subjects, there was no difference in the rate of decline in percent‐predicted FEV 1 by ethnicity in any geographic region. This is consistent with our prior findings on overall rate of percent‐predicted FEV 1 decline and pulmonary function differences by ethnicity …”

“…In the largest database of Hispanic patients with CF, we found that pulmonary function disparities between Hispanic and non‐Hispanic white subjects vary among geographic regions, even with adjustment for factors known to influence pulmonary function. In all geographic regions, the difference in percent‐predicted FEV 1 between Hispanic and non‐Hispanic white subjects varied from the overall ethnic disparity of 5.8% in percent‐predicted FEV 1 that we had found in our previous work . The ethnic gap in pulmonary function was significantly wider in the West than in the other geographic regions for all measures (percent‐predicted FVC, FEV 1 , FEV 1 /FVC, FEF 25%‐75% ).…”

“…Hispanic subjects in all geographic regions were more likely to have unclassified CFTR mutations and less likely to have CFTR class I‐III. We have previously shown that there were no significant differences in the ethnic gap in pulmonary function between CFTR mutation severity classes . The Hispanic ethnicity is heterogeneous with genetically diverse heritages that vary across the US regions due to distinct migration patterns.…”

“…Despite great advancements in care and outcomes, Hispanic patients with cystic fibrosis (CF) have worse outcomes compared to non‐Hispanic white patients. Hispanic patients have a higher rate of mortality than do non‐Hispanic white patients and Hispanic youth with CF have a worse pulmonary function . Our group has shown that Hispanic youth with CF have 5.8% lower percent‐predicted forced expiratory volume in 1 second (FEV 1 ) compared with non‐Hispanic white youth .…”

“…For example, pulmonary function is strongly influenced by CFTR mutation severity; however, Hispanic subjects have worse pulmonary function than non‐Hispanic white subjects in all CFTR mutation severity classes . In our prior analysis of pulmonary function, Hispanic subjects still had a worse pulmonary function, even when controlling for measures of respiratory infections, environmental exposures, and socioeconomic status known to affect pulmonary function . Many of these factors may not uniformly affect Hispanic patients across the United States.…”