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

Low prevalence of peptic ulcer disease in hospitalized patients with cystic fibrosis: A national database study

BACKGROUND

Although cystic fibrosis (CF) is widely considered a lung disease, the prevalence of CF-specific gastrointestinal symptoms and diseases has continued to rise. Peptic ulcer disease (PUD) has not been well-studied among people with CF (PwCF) and may be a common cause of abdominal symptoms. In PwCF, impaired bicarbonate secretion and unbuffered gastric acid production have been attributed to the development of ulcers, although ulcers remain uncommon. The objective of this study was to evaluate the prevalence of PUD in PwCF and assess for possible contributing factors.

METHODS

This study utilized the National Inpatient Sample (NIS) database. All patients 18 years or older with CF were identified from 2014 to 2019. Relevant patient characteristics and procedures were identified using ICD-9 and ICD-10 codes. Linear trend, bivariate analyses, and multiple regression analysis were performed. The outcomes of interest were peptic ulcer disease, pancreatic insufficiency, and nonalcoholic steatohepatitis or NASH. All analyses accounted for complex sampling scheme of the NIS.

RESULTS

The total prevalence of PwCF in the National Inpatient Sample (NIS) database was 0.08 %, and the number was stable year to year from 2014 to 2019. Hispanic patients were more likely to be diagnosed with PUD than other white (aOR 1.802 [1.311,2.476]). Multiple regression analysis indicated that PUD in PwCF was strongly associated with a diagnosis of NASH (aOR 2.421[1.197, 4.898]). PUD patients were less likely to have pancreatic insufficiency compared to the non-PUD group (aOR 0.583 [0.455, 0.745]).

CONCLUSION

Although cystic fibrosis has been historically known as a disease of childhood, advancements in therapy have led to prolonged life expectancy and higher prevalence for cystic fibrosis-related digestive diseases. This study revealed a low prevalence of PUD in PwCF. Hispanics and those with NASH are more likely to develop peptic ulcers.

Improved detection of cystic fibrosis by the California Newborn Screening Program for all races and ethnicities

BACKGROUND

Newborn screening (NBS) for cystic fibrosis (CF) is universal in the United States. Protocols vary but include an immunoreactive trypsinogen (IRT) level and CFTR variant panel. California CF NBS has a 3-step screening: IRT level, variant panel, and CFTR sequencing if only one variant identified on panel.

METHODS

This was a cohort study of infants with CF born in California (2007-2021) to examine racial and ethnic differences in having a false-negative NBS result for CF and at which step the false-negative occurred. We examined how different CFTR variant panels would improve detection of variants by race and ethnicity: original 39-variant panel, current 75-variant panel, and all 402 disease-causing CFTR variants in the CFTR2 database.

RESULTS

Of the 912 infants born in California with CF, 84 had a false-negative result: 38 due to low IRT level and 46 with a high IRT value (but incomplete variant detection). Asian (OR 6.3) and Black infants (OR 2.5) were more likely to have a false-negative screening result than non-Hispanic white infants. The majority of false-negative screening (but CF diagnosis) cases among American Indian/Native Alaskan and non-Hispanic White infants were due to low IRT levels. The majority of Asian and Hispanic infants with false-negative screening had no variants detected. Detection of two CFTR variants was improved with the 75-variant panel in Black, Hispanic, and non-Hispanic White infants and with the 402-variant panel in Black, Hispanic, non-Hispanic White, and other race infants.

CONCLUSIONS

Larger CFTR panels in NBS improved the detection of CF in all races and ethnicities.

Racial inequities and rare CFTR variants: Impact on cystic fibrosis diagnosis and treatment

Cystic fibrosis (CF) has been traditionally viewed as a disease that affects White individuals. However, CF occurs among all races, ethnicities, and geographic ancestries. The disorder results from mutations in the CF transmembrane conductance regulator (CFTR). Varying incidence of CF is reported among Black, Indigenous, and People of Color (BIPOC), who typically exhibit worse clinical outcomes. These populations are more likely to carry rare CFTR variants omitted from newborn screening panels, leading to disparities in care such as delayed diagnosis and treatment. In this study, we present a case-in-point describing an individual of Gambian descent identified with CF. Patient genotype includes a premature termination codon (PTC) (c.2353C>T) and previously undescribed single nucleotide deletion (c.1970delG), arguing against effectiveness of currently available CFTR modulator-based interventions. Strategies for overcoming these two variants will likely include combinations of PTC suppressors, nonsense mediated decay inhibitors, and/or alternative approaches (e.g. gene therapy). Investigations such as the present study establish a foundation from which therapeutic treatments may be developed. Importantly, c.2353C>T and c.1970delG were not detected in the patient by traditional CFTR screening panels, which include an implicit racial and ethnic diagnostic bias as these tests are comprised of mutations largely observed in people of European ancestry. We suggest that next-generation sequencing of CFTR should be utilized to confirm or exclude a CF diagnosis, in order to equitably serve BIPOC individuals. Additional epidemiologic data, basic science investigations, and translational work are imperative for improving understanding of disease prevalence and progression, CFTR variant frequency, genotype-phenotype correlation, pharmacologic responsiveness, and personalized medicine approaches for patients with African ancestry and other historically understudied geographic lineages.

Evaluating precision medicine tools in cystic fibrosis for racial and ethnic fairness

Introduction

Patients with cystic fibrosis (CF) experience frequent episodes of acute decline in lung function called pulmonary exacerbations (PEx). An existing clinical and place-based precision medicine algorithm that accurately predicts PEx could include racial and ethnic biases in clinical and geospatial training data, leading to unintentional exacerbation of health inequities.

Methods

We estimated receiver operating characteristic curves based on predictions from a nonstationary Gaussian stochastic process model for PEx within 3, 6, and 12 months among 26,392 individuals aged 6 years and above (2003-2017) from the US CF Foundation Patient Registry. We screened predictors to identify reasons for discriminatory model performance.

Results

The precision medicine algorithm performed worse predicting a PEx among Black patients when compared with White patients or to patients of another race for all three prediction horizons. There was little to no difference in prediction accuracies among Hispanic and non-Hispanic patients for the same prediction horizons. Differences in F508del, smoking households, secondhand smoke exposure, primary and secondary road densities, distance and drive time to the CF center, and average number of clinical evaluations were key factors associated with race.

Conclusions

Racial differences in prediction accuracies from our PEx precision medicine algorithm exist. Misclassification of future PEx was attributable to several underlying factors that correspond to race: CF mutation, location where the patient lives, and clinical awareness. Associations of our proxies with race for CF-related health outcomes can lead to systemic racism in data collection and in prediction accuracies from precision medicine algorithms constructed from it.

Social-environmental phenotypes of rapid cystic fibrosis lung disease progression in adolescents and young adults living in the United States

Background

Cystic fibrosis (CF) is a genetic disease but is greatly impacted by non-genetic (social/environmental and stochastic) influences. Some people with CF experience rapid decline, a precipitous drop in lung function relative to patient- and/or center-level norms. Those who experience rapid decline in early adulthood, compared to adolescence, typically exhibit less severe clinical disease but greater loss of lung function. The extent to which timing and degree of rapid decline are informed by social and environmental determinants of health (geomarkers) is unknown.

Methods

A longitudinal cohort study was performed (24,228 patients, aged 6-21 years) using the U.S. CF Foundation Patient Registry. Geomarkers at the ZIP Code Tabulation Area level measured air pollution/respiratory hazards, greenspace, crime, and socioeconomic deprivation. A composite score quantifying social-environmental adversity was created and used in covariate-adjusted functional principal component analysis, which was applied to cluster longitudinal lung function trajectories.

Results

Social-environmental phenotyping yielded three primary phenotypes that corresponded to early, middle, and late timing of peak decline in lung function over age. Geographic differences were related to distinct cultural and socioeconomic regions. Extent of peak decline, estimated as forced expiratory volume in 1 s of % predicted/year, ranged from 2.8 to 4.1 % predicted/year depending on social-environmental adversity. Middle decliners with increased social-environmental adversity experienced rapid decline 14.2 months earlier than their counterparts with lower social-environmental adversity, while timing was similar within other phenotypes. Early and middle decliners experienced mortality peaks during early adolescence and adulthood, respectively.

Conclusion

While early decliners had the most severe CF lung disease, middle and late decliners lost more lung function. Higher social-environmental adversity associated with increased risk of rapid decline and mortality during young adulthood among middle decliners. This sub-phenotype may benefit from enhanced lung-function monitoring and personalized secondary environmental health interventions to mitigate chemical and non-chemical stressors.

Health inequities in the modulator era

PURPOSE OF REVIEW

To discuss the existing health inequities in people with cystic fibrosis (CF) and how the recent development of cystic fibrosis transmembrane regulator (CFTR) modulators may impact these inequities.

RECENT FINDINGS

People with CF (pwCF) from low socioeconomic status (SES) have more pulmonary exacerbations, worse nutritional status, lower pulmonary function, and an increased mortality rate with less access to lung transplantation. pwCF who identify as racial and ethnic minorities have earlier mortality, lower lung function, are less likely to be detected on newborn screening resulting in a delayed diagnosis, are underrepresented in clinic trials, and less likely to be eligible for a CFTR modulator. Female sex is associated with more pulmonary exacerbations and earlier mortality. Sexual gender minorities are a vulnerable population with worse health outcomes, and more research is needed in CF. CFTR modulators are inaccessible to low to middle-income countries due to significant cost burden.

SUMMARY

People with CF from low SES, racial and ethnic minorities, female sex, and sexual gender minorities face health inequities. CFTR modulator use will further widen existing health inequities given the unequal access to modulators based on nonqualifying genetics and exorbitant cost restricting use both on an individual and global level.

Cystic fibrosis-related mortality in the United States from 1999 to 2020: an observational analysis of time trends and disparities

Cystic fibrosis transmembrane conductance regulator modulators have revolutionized cystic fibrosis (CF) care in the past decade. This study explores the CF-related mortality trends in the US from 1999 to 2020. We extracted CF-related mortality data from the CDC WONDER database. CF age-standardized mortality rates (ASMRs) were identified by ICD-10 code E84 and were stratified by demographic and geographical variables. Temporal trends were analyzed using Joinpoint modeling. CF-related ASMRs decreased from 1.9 to 1.04 per million population (p = 0.013), with a greater reduction in recent years. This trend was replicated in both sexes. The median age of death increased from 24 to 37 years. CF mortality rates decreased across sex, white race, non-Hispanic ethnicity, census regions, and urbanization status. Incongruent trends were reported in non-white races and Hispanic ethnicity. A lower median age of death was observed in women, non-white races, and Hispanic ethnicity. SARS-CoV-2 infection was the primary cause of death in 1.7% of CF decedents in 2020. The national CF-related mortality rates declined and the median age of death among CF decedents increased significantly indicating better survival in the recent years. The changes were relatively slow during the earlier period of the study, followed by a greater decline lately. We observed patterns of sex, ethnic, racial, and geographical disparities associated with the worsening of the gap between ethnicities, narrowing of the gap between races and rural vs. urban counties, and closing of the gap between sexes over the study period.

Ethnic differences in staphylococcus aureus acquisition in cystic fibrosis

BACKGROUND

Hispanic people with CF (pwCF) have increased morbidity than non-Hispanic White pwCF, including increased risk of Pseudomonas aeruginosa. We aimed to determine if Staphylococcus aureus (S. aureus) acquisition varies between Hispanic and non-Hispanic White pwCF.

METHODS

This longitudinal cohort study of pwCF ages 0-25 years in the CF Foundation Patient Registry compared acquisition of methicillin-sensitive S. aureus (MSSA), methicillin-resistant S. aureus (MRSA), persistent MRSA between Hispanic and non-Hispanic White pwCF. Risk of acquisition was assessed by Kaplan-Meier survival curves and its association with ethnicity was evaluated using Cox regressions. Adjusted associations were evaluated using multivariate Cox models adjusting for sex, age of entry into CFFPR, CFTR variant severity, pancreatic insufficiency, CF-related diabetes, maternal education, insurance status.

RESULTS

Of 10,640 pwCF, 7.5% were Hispanic and 92.5% were non-Hispanic White. Hispanic pwCF had a 19% higher risk of acquiring MSSA (HR 1.19, 95% CI 1.10-1.28, p<0.001) and 13% higher risk of acquiring MRSA (HR 1.13, 95% CI 1.02-1.26, p = 0.02) than non-Hispanic White pwCF. The difference in persistent MRSA between ethnicities did not reach statistical significance. After adjusting for confounding variables, only the risk of MSSA was significantly associated with ethnicity. Compared to non-Hispanic White pwCF, Hispanic pwCF acquired MSSA and MRSA at younger median ages (4.9 vs. 3.8 years (p<0.001), 22.4 vs. 20.8 years (p = 0.02).

CONCLUSION

Hispanic pwCF <25 years of age have an increased risk of acquiring MSSA and acquired MSSA and MRSA at an earlier age. Differences in S. aureus acquisition may contribute to increased morbidity in Hispanic pwCF.

Aiming to Improve Equity in Pulmonary Health: Cystic Fibrosis

This review summarizes the evidence of health disparities in cystic fibrosis (CF), an autosomal recessive genetic disorder with substantial variation in disease progression and outcomes. We review disparities by race, ethnicity, socioeconomic status, geographic location, gender identity, or sexual orientation documented in the literature. We outline the mechanisms that generate and perpetuate such disparities across levels and domains of influence and assess the implications of this evidence. We then recommend strategies for improving equity in CF outcomes, drawing on recommendations for the general population and considering approaches specific to people living with CF.

Center-level self-study identifies opportunities to advance equity in cystic fibrosis clinical trial participation

Clinical trials are a necessary tool for evaluating the effectiveness of newly developed treatments and interventions for cystic fibrosis (CF). Prior work demonstrated a proportional underrepresentation of people with CF (pwCF) identifying as part of a minoritized racial or ethnic group in clinical trials. In order to establish a baseline for improvement efforts, we undertook a center-level self-study to evaluate if the racial and ethnic backgrounds of pwCF participating in clinical trials at our CF Center in New York City reflect our overall patient diversity (N = 200; 55 pwCF identifying as part of a minoritized racial or ethnic group and 145 pwCF identifying as non-Hispanic White). A smaller proportion of pwCF identifying as part of a minoritized racial or ethnic group participated in a clinical trial as compared to pwCF identifying as non-Hispanic White (21.8% vs. 35.9%, P = 0.06). A similar trend was present for pharmaceutical clinical trials (9.1% vs. 16.6%, P = 0.3). When limiting the study population to the pwCF most likely to be eligible for a CF pharmaceutical clinical trial, a larger proportion of pwCF identifying as part of a minoritized racial or ethnic group participated in a pharmaceutical clinical trial as compared to pwCF identifying as non-Hispanic White (36.4% vs. 19.6%, P = 0.2). No pwCF identifying as part of a minoritized racial or ethnic group participated in an offsite clinical trial. Efforts to improve the racial and ethnic diversity of pwCF in clinical trials, both onsite and offsite, will require a shift in how recruitment opportunities are identified and communicated to pwCF.

Disparities and therapeutic advances in cystic fibrosis

Cystic fibrosis (CF) has seen a multitude of therapeutic advances targeting its downstream effects. This has led to a steady increase in survival over the past few decades. The recent development of disease-modifying drugs targeting the underlying CFTR mutation has revolutionized treatment for CF. Despite these advances, individuals with CF who are racial and ethnic minorities, from low socioeconomic status, or female sex have worse clinical outcomes. The inequitable access to CFTR modulators from cost and/or genetic eligibility has the potential to further worsen the existing health disparities seen within the CF community.

Detection of disease-causing CFTR variants in state newborn screening programs

BACKGROUND

Newborn screening (NBS) algorithms for cystic fibrosis (CF) vary in the United State of America and include different cystic fibrosis transmembrane conductance regulator (CFTR) variants. CFTR variant distribution varies among racial and ethnic groups.

OBJECTIVE

Our objectives were to identify differences in detection rate by race and ethnicity for CFTR variant panels, identify each US state detection rate for CFTR variant panels, and describe the rate of false-negative NBS and delayed diagnoses by race and ethnicity.

METHODS

This is a cross-sectional analysis of the detection rate of at least 1 CFTR variant for seven panels by race and ethnicity in genotyped people with CF (PwCF) or CFTR-related metabolic syndrome (CRMS)/CFTR-related disorders in CF Foundation Patient Registry (CFFPR) in 2020. We estimated the case detection rate of CFTR variant panels by applying the detection rate to Census data. Using data from CFFPR, we compared the rate of delayed diagnosis or false-negative NBS by race and ethnicity.

RESULTS

For all panels, detection of at least 1 CFTR variant was highest in non-Hispanic White PwCF (87.5%-97.0%), and lowest in Black, Asian, and Hispanic PwCF (41.9%-93.1%). Detection of at least 1 CFTR variant was lowest in Black and Asian people with CRMS/CFTR-related disorders (48.4%-64.8%). States with increased racial and ethnic diversity have lower detection rates for all panels. Overall, 3.8% PwCF had a false-negative NBS and 11.8% had a delayed diagnosis; Black, Hispanic, and mixed-race PwCF were overrepresented.

CONCLUSION

CFTR variant panels have lower detection rates in minoritized racial and ethnic groups leading to false-negative NBS, delayed diagnosis, and likely health disparities.

Disparities in first evaluation of infants with cystic fibrosis since implementation of newborn screening

OBJECTIVE

We evaluated whether implementation of cystic fibrosis (CF) newborn screening (NBS) leads to equitable timeliness of initial evaluation. We compared age at first event (AFE, age at sweat test, encounter and/or care episode) between infants categorized as Black/African American, American Indian/ Native Alaskan, Asian, and/or Hispanic and/or other (Group 1) to White and not Hispanic infants (Group 2).

METHODS

This retrospective cohort study from the Cystic Fibrosis Foundation Patient Registry (CFFPR) included infants born 2010-2018. Race and ethnicity categories followed US Census definitions. The primary outcome was AFE; the secondary outcome was weight for age (WFA) z-score averaged 12 to < 24 months. We compared distributions by Wilcoxon rank-sum test and proportions by Chi-square or Fisher's exact tests. A nested cohort study used a linear mixed effects model of variables that affect WFA, chosen a priori, to evaluate associations with 1-year WFA z-score.

RESULTS

Among 6354 infants, 21% were in Group 1. Group 1 median AFE was 31 days (IQR 19, 49) and Group 2 was 22 days (IQR 14,36) (p< .001). Median WFA z-score at 1-2 years was lower in Group 1. In 3017 infants with complete data on variables of interest, AFE, Black race, CFTR variant class I-III, prematurity and public insurance were associated with lower 1-year WFA z-score.

CONCLUSIONS

Differences in AFE for infants with CF from historically marginalized groups may exacerbate long standing health disparities. We speculate that inequitable identification of CFTR gene variants and/or bias may influence timeliness of evaluation after an out-of-range NBS.

Toward a Broader Understanding of Cystic Fibrosis Epidemiology and Its Impact on Clinical Manifestations

The incidence of cystic fibrosis remains constant in North America and Western Europe is 1 in 3500 live births, but survival and quality of life have improved. The cystic fibrosis population has shifted toward the adult age range with a concomitant shift in the spectrum of complications. Survival increased because of aggressive symptomatic therapy, earlier diagnosis by newborn screening, and the introduction of modulators of the cystic fibrosis transmembrane conductance regulator, so that predicted median survival age is now about 50 years. In the United States, members of low socioeconomic status populations or members of racial or ethnic minorities have benefitted less from these advances.

Cystic Fibrosis: Highly Effective Targeted Therapeutics and the Impact on Sex and Racial Disparities

People with Cystic Fibrosis (CF) are living longer and healthier lives due in part to new therapies, called Cystic Fibrosis Transmembrane Conductance Regulator (CFTR) modulators. However, disparities in outcomes still exist, with females demonstrating a shorter life expectancy than males; this is opposed to the typical female versus male life expectancy in the general United States population. In addition, minority populations such as those of Hispanic ethnicity and African Americans are less frequently eligible for these new CFTR modulators. The mechanisms driving this difference and the relative contribution of CFTR to the etiology are not yet elucidated.

Socioeconomic determinants of respiratory health in patients with cystic fibrosis: implications for treatment strategies

INTRODUCTION

Great variation exists in the progression and outcomes of cystic fibrosis (CF) lung disease, due to both genetic and environmental influences. Social determinants mediate environmental exposures and treatment success; people with CF from socioeconomically disadvantaged backgrounds have worse health and die younger than those in more advantaged positions.

AREAS COVERED

This paper reviews the literature on the mechanisms that are responsible for generating and sustaining disparities in CF health, and the ways by which social determinants translate into health advantages or disadvantages in people with CF. The authors make recommendations for addressing social risk factors in CF clinical practice.

EXPERT OPINION

Socioeconomic factors are not dichotomous and their impact is felt at every step of the social ladder. CF care programs need to adopt a systematic protocol to screen for health-related social risk factors, and then connect patients to available resources to meet individual needs. Considerations such as daycare, schooling options, living and working conditions, and opportunities for physical exercise and recreation as well as promotion of self-efficacy are often overlooked. In addition, advocacy for changes in public policies on health insurance, environmental regulations, social welfare, and education would all help address the root causes of CF health inequities.

Newborn Screening for Cystic Fibrosis: A Qualitative Study of Successes and Challenges from Universal Screening in the United States

Cystic fibrosis (CF) newborn screening (NBS) was universally adopted in 2009 in the United States. Variations in NBS practices between states may impact the timing of diagnosis and intervention. Quantitative metrics can provide insight into NBS programs (NBSP), but the nuances cannot be elucidated without additional feedback from programs. This study was designed to determine facilitators and barriers to timely diagnosis and intervention following NBS for CF. The median age at the first CF event for infants with CF within each state was used to define early and late states (n = 15 per group); multiple CF centers were invited in states with more than two CF centers. Thirty states were eligible, and 61 NBSP and CF centers were invited to participate in structured interviews to determine facilitators and barriers. Once saturation of themes was reached, no other interviews were conducted. Forty-five interviews were conducted (n = 16 early CF center, n = 12 late CF center, n = 11 early NBSP, and n = 6 late NBSP). Most interviewees reported good communication between CF centers and NBSP. Communication between primary care providers (PCPs) and families was identified as a challenge, leading to delays in referral and subsequent diagnosis. The misperception of low clinical risk in infants from racial and ethnic minority groups was a barrier to early diagnostic evaluation for all groups. NBSP and CF centers have strong relationships. Early diagnosis may be facilitated through more engagement with PCPs. Quality improvement initiatives should focus on continuing strong partnerships between CF centers and NBS programs, improving education, communication strategies, and partnerships with PCPs, and improving CF NBS timeliness and accuracy.

Left behind: The potential impact of CFTR modulators on racial and ethnic disparities in cystic fibrosis

The advent of CFTR modulators, a genomic specific medication, revolutionized the treatment of CF for many patients. However, given that these therapeutics were only developed for specific CFTR mutations, not all people with CF have access to such disease-modifying drugs. Racial and ethnic minority groups are less likely to have CFTR mutations that are approved for CFTR modulators. This exclusion has the potential to widen existing health disparities.

Increasing life expectancy in cystic fibrosis: Advances and challenges

Since the first description of cystic fibrosis in 1938, there have been significant advances in both quality of life and longevity for people living with this disease. In this article we describe the milestones of the last 80 years and what we perceive to be the remaining barriers to normalcy for this population.

Evaluating Differences in the Disease Experiences of Minority Adults With Cystic Fibrosis

Extensive research has demonstrated disparities in health outcomes and survival between non-Hispanic Caucasian (NHC) and non-Caucasian or Hispanic (minority) persons with cystic fibrosis (CF) in the United States (US). However, very little research has been done to explore the disease experiences of racial and ethnic minority persons with CF. Adult subjects with CF were approached for study participation and to characterize their experiential disease perceptions. Survey data were analyzed using Chi-Square tests and Mann-Whitney U-test for basic categorical and continuous variables, and Kruskal-Wallis one-way ANOVA using ranks for Likert scales. Minority persons reported significantly lower scores (more negative experience) when comparing themselves to others with CF (15.18 ± 2.89 vs 18.40 ± 3.18, P < .01), particularly in the areas of representation in research, experience, and support. We were able to identify the unique experiences of minority persons with CF, including perceived lower disease understanding and poorer representation compared to most others with CF. Further large studies are needed to develop and assess interventions that may be useful for serving these diverse populations.

Assessment of hospitalization rates, factors associated with hospitalization and in-patient mortality in pediatric patients with cystic fibrosis

INTRODUCTION

Cystic fibrosis (CF), an inherited autosomal recessive disease that results in the accumulation of mucus and damage primarily to the respiratory and digestive tracts is caused by mutations in the cystic fibrosis transmembrane conductance regulator (CFTR) gene. In the United States, it has been estimated that CF occurs in 1 out of 3500 infants. The objective of this study was to explore the patient and hospital characteristics associated with CF hospitalizations and inpatient mortality in pediatric CF patients.

METHODS

Utilizing the National Inpatient Sample database from 2008 to 2017, a retrospective cohort study was conducted to analyze the hospitalization rates, associated factors, and the inpatient mortality of CF patients 0-17 years of age. Hospitalizations with a diagnosis of CF were identified with ICD-9-CM and ICD-10-CM codes. Adjusted survey logistic regression models were utilized to determine factors associated with CF hospitalizations and in-hospital deaths in CF patients.

RESULTS

There were a total of 98,660 (about 0.2%) CF hospitalizations in patients 17 years of age or younger during the study period. Non-Hispanic (NH) White CF patients had the highest prevalence of CF (26.30 per 10,000 hospitalizations). The prevalence of inpatient deaths were highest among those identified as NH-Others and NH-Blacks (71.35 and 68.83 per 10,000 CF hospitalizations, respectively. When compared with NH-White category, those belonging to NH-Black, Hispanic and Other racial/ethnic sub-group had reduced odds of being hospitalized with CF.

DISCUSSION

Despite our finding of an increased likelihood of being hospitalized for CF among NH-White and male pediatric patients, no association between race or sex and CF inpatient death was observed when adjusted for covariates. More research is needed to determine the impact of sex and race on CF mortality rates.

Patterns of Health Insurance Coverage and Lung Disease Progression in Adolescents and Young Adults with Cystic Fibrosis

Rationale: Health insurance coverage has been implicated as a socioeconomic factor affecting clinical outcomes in patients with cystic fibrosis (CF), but evidence for this is mixed and varies by age.Objectives: Focusing on adolescents and young adults with CF, we examined how multiyear patterns of health insurance coverage were associated with lung function decline and related outcomes.Methods: We used data from the 2000 to 2015 CF Foundation Patient Registry to classify patients in three cohorts (ages 12-17 yr, adolescents; 18-23 yr, transitioning to adulthood; and 24-29 yr, young adults) according to health insurance coverage, as follows: continuous private, continuous public, intermittent public, and coverage gaps. The primary outcome was the percentage predicted forced expiratory volume in 1 second (FEV₁pp), which was modeled using mixed-effects regression. Additional outcomes included outpatient visits, hospital days for pulmonary exacerbation treatment, bacterial colonization, and body mass index. Outcomes were assessed over a 6-year period (e.g., ages 12-17 yr), whereas exposures were assessed over the prior 6 years (e.g., ages 6-11 yr).Results: The three cohorts included 3,365, 2,800, and 1,807 patients, respectively. The highest rate of FEV₁pp decline was found in the middle cohort, with the annual decline being steeper among patients with continuous public (-3.1/yr; 95% confidence interval [CI], -3.3 to -2.8) or intermittent public (-2.4/yr; 95% CI, -2.6 to -2.2) coverage compared with patients with continuous private coverage (-2.1/yr; 95% CI, -2.2 to -2.0). These differences were not explained by differences in outpatient care utilization.Conclusions: During the transition to adulthood, use of public insurance was associated with accelerated lung function decline among patients with CF. The role of insurance as a causal factor in this decline or proxy for other socioeconomic characteristics should be explored in further studies.

Disease burden in people with cystic fibrosis heterozygous for F508del and a minimal function mutation

BACKGROUND

People with cystic fibrosis (CF) heterozygous for F508del-CFTR and a minimal function CFTR mutation (F/MF) that results in no CFTR protein or results in CFTR protein that is not responsive to tezacaftor, ivacaftor, and tezacaftor/ivacaftor in vitro comprise a sizeable percentage of the US CF population. This retrospective, cross-sectional, observational study aimed to characterize CF burden in this subpopulation.

METHODS

People ≥2 years of age in the US CF Foundation Patient Registry with a CF diagnosis, F/MF genotype, and ≥1 encounters in 2017 were included. Descriptive analyses assessed lung function, nutritional parameters, microbiology, hospitalization and pulmonary exacerbation rates, and CF-related complications. Results were stratified by age group; select characteristics were summarized by percent predicted FEV₁ (ppFEV₁) and ethnicity.

RESULTS

5348 people met inclusion criteria. Rates of positive bacterial cultures, pulmonary exacerbations, and hospitalizations were generally higher in older age groups. Prevalence of prescribed symptomatic CF therapies was substantial and also generally higher in older age groups. ppFEV₁ was lower in older age groups. A greater percentage of adolescents and adults reported complications, including cirrhosis, osteoporosis, osteopenia, and sinus disease, than younger age groups. Increased prevalence of cultured Pseudomonas aeruginosa and prescribed chronic therapy was seen with decreasing ppFEV₁. In each age group, ppFEV₁ was slightly higher in the non-Hispanic cohort than in the Hispanic cohort.

CONCLUSIONS

People with F/MF genotypes have substantial disease burden that worsened in older age groups consistent with the progressive nature of CF, indicating need for additional treatment options in this subpopulation.

Cystic fibrosis patients of minority race and ethnicity less likely eligible for CFTR modulators based on CFTR genotype

BACKGROUND

Cystic fibrosis transmembrane conductance regulator (CFTR) modulators are disease-modifying medications for cystic fibrosis (CF) and are shown to be efficacious for only specific CFTR mutations. CFTR mutation frequency varies by ancestry, which is different from but related to demographic racial and ethnic group. Eligibility for CFTR modulator therapy has not been previously reported by race and ethnicity.

METHODS

We conducted a cross-sectional study of patients in the 2018 CF Foundation Patient Registry. We analyzed the percentage of patients in each US Census defined racial and ethnic group eligible for CFTR modulators based on CFTR mutations approved by the US FDA and then based on both mutations and FDA approval by age. We compared lung function based on CFTR modulator eligibility and prescription.

FINDINGS

Based on CFTR mutations alone, 92.4% of non-Hispanic White patients, 69.7% of Black/African American patients, 75.6% of Hispanic patients, and 80.5% of other race patients eligible for CFTR modulators. For each CFTR modulator, Black/African American patients were least likely to have eligible mutations, and non-Hispanic White patients were most likely. There was no difference in the disparity between racial and/or ethnic groups with the addition of current FDA approval by age. The lowest pulmonary function in the cohort was seen in non-Hispanic White, Black/African American, and Hispanic patients not eligible for CFTR modulators.

INTERPRETATION

Patients with CF from minority groups are less likely to be eligible for CFTR modulators. Because people with CF who are racial and ethnic minorities have increased disease severity and earlier mortality, this will further contribute to health disparities.

Management of chronic pulmonary disease in the time of coronavirus disease 2019

PURPOSE OF REVIEW

The purpose of this review is to discuss the most recent data describing the impact of coronavirus disease 2019 (COVID-19) on the pediatric population with chronic pulmonary disease. We specifically focus on children with asthma, cystic fibrosis (CF), and lung transplant recipients.

RECENT FINDINGS

Children with asthma, CF, and lung transplant recipients do not appear to have an increased risk of morbidity or mortality with COVID-19 infection compared to the general pediatric population. Data does not support the change or withdrawal of any asthma or CF maintenance medications; however, does advocate for the cessation of aerosolized medications whenever possible to minimize transmission risk. It may not be necessary to adjust immunosuppressive therapy when managing COVID-19 in pediatric lung transplant patients. Mechanisms of infection in airway epithelial cells in children may differ from adults, resulting in a milder phenotype.

SUMMARY

Current data about pediatric patients with chronic lung disease infected with severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) is promising but remains scarce. Additional study is needed to definitively understand the complex interplay of the SARS-CoV-2 virus in the airway of children with chronic lung disease, how it differs from adults, and how best to manage the symptoms of acute infection.

Early acquisition and conversion of Pseudomonas aeruginosa in Hispanic youth with cystic fibrosis in the United States

BACKGROUND

For unknown reasons, Hispanic patients with cystic fibrosis (CF) have more severe pulmonary disease than non-Hispanic white patients. In CF, the pulmonary pathogen Pseudomonas aeruginosa is associated with worse outcomes. We sought to determine if Hispanic patients with CF are at an increased risk of acquiring P. aeruginosa or acquire it earlier than non-Hispanic white patients.

METHODS

This is a longitudinal study comparing the timing and risk of acquisition of different forms of P. aeruginosa between Hispanic and non-Hispanic white patients aged 0-21 years old with CF in the CF Foundation Patient Registry (CFFPR) in 2008-2013. The age at the initial acquisition of P. aeruginosa (initial acquisition, mucoid, chronic, multidrug-resistant) was summarized using Kaplan-Meier survival curves and analyzed using Cox proportional hazards regression models.

RESULTS

Of 10,464 patients, 788 (7.5%) were Hispanic and 9,676 (92.5%) were non-Hispanic white. Hispanic patients acquired all forms of P. aeruginosa at a younger age than non-Hispanic white patients. Hispanic patients had a higher risk of acquiring P. aeruginosa than non-Hispanic white patients: the hazard ratio (HR) was 1.26 (95% CI 1.16-1.38, p<0.001) for initial P. aeruginosa, 1.59 (95% CI 1.43-1.77, p<0.001) for mucoid P. aeruginosa, 1.91 (95% CI 1.64-2.23, p<0.001) for multidrug-resistant P. aeruginosa, and 1.39 (95% CI 1.25-1.55, p<0.001) for chronic P. aeruginosa.

CONCLUSIONS

Hispanic patients have an increased risk of acquiring P. aeruginosa and acquire it at an earlier age than non-Hispanic white patients in the United States. This may contribute to increased morbidity and mortality in Hispanic patients with CF.

The CFTR variant profile of Hispanic patients with cystic fibrosis: Impact on access to effective screening, diagnosis, and personalized medicine

Hispanic patients comprise an appreciable and increasing proportion of patients with cystic fibrosis (CF) in the United States (US). Hispanic patients with CF are known to have increased morbidity and mortality compared to non-Hispanic white patients with CF, and ongoing investigations are underway to identify contributing factors amenable to intervention in order to address the disparate health outcomes. One contributing factor is the different CF transmembrane conductance regulator (CFTR) variant profile observed in Hispanic patients with CF. The most common CFTR variant, p.Phe508del (legacy name F508del), is proportionally underrepresented in Hispanic patients with CF. This difference has implications for prenatal screening, newborn screening (NBS), and CFTR variant-specific therapeutic options. In particular, the recent approval of a highly effective CFTR modulator for patients carrying at least one copy of F508del, elexacaftor/tezacaftor/ivacaftor triple combination therapy, underscores the potential for unequal access to personalized treatment for Hispanic patients with CF. We report the CFTR variant profiles of Hispanic patients with CF and non-CF Hispanic infants with a false-positive New York State CF NBS at a single center in New York City over a 5-year study period, as an opportunity to address the racial and ethnic disparities that currently exist in CF screening, diagnosis, and treatment. In addition to the previously documented disparate prevalence of the CFTR variant F508del in Hispanic patients, we observed two CFTR variants, p.His609Arg (legacy name H609R) and p.Thr1036Asn (legacy name T1036N), frequently identified in our Hispanic patients of Ecuadorian and Mexican ancestry, respectively, that are not well-described in the US population. The presence of population-specific and individually rare CFTR variants in Hispanic patients with CF further accentuates the disparity in health outcomes, as these CFTR variants are often absent from prenatal and NBS CFTR variant panels, potentially delaying diagnosis, and without an approved CFTR variant-specific therapy.

Identification of CFTR variants in Latino patients with cystic fibrosis from the Dominican Republic and Puerto Rico

BACKGROUND

In cystic fibrosis (CF), the spectrum and frequency of CFTR variants differ by geography and race/ethnicity. CFTR variants in White patients are well-described compared with Latino patients. No studies of CFTR variants have been done in patients with CF in the Dominican Republic or Puerto Rico.

METHODS

CFTR was sequenced in 61 Dominican Republican patients and 21 Puerto Rican patients with CF and greater than ​​​​60 mmol/L sweat chloride. The spectrum of CFTR variants was identified and the proportion of patients with 0, 1, or 2 CFTR variants identified was determined. The functional effects of identified CFTR variants were investigated using clinical annotation databases and computational prediction tools.

RESULTS

Our study found 10% of Dominican patients had two CFTR variants identified compared with 81% of Puerto Rican patients. No CFTR variants were identified in 69% of Dominican patients and 10% of Puerto Rican patients. In Dominican patients, there were 19 identified CFTR variants, accounting for 25 out of 122 disease alleles (20%). In Puerto Rican patients, there were 16 identified CFTR variants, accounting for 36 out of 42 disease alleles (86%) in Puerto Rican patients. Thirty CFTR variants were identified overall. The most frequent variants for Dominican patients were p.Phe508del and p.Ala559Thr and for Puerto Rican patients were p.Phe508del, p.Arg1066Cys, p.Arg334Trp, and p.I507del.

CONCLUSIONS

In this first description of the CFTR variants in patients with CF from the Dominican Republic and Puerto Rico, there was a low detection rate of two CFTR variants after full sequencing with the majority of patients from the Dominican Republic without identified variants.

Functional Profiling of CFTR-Directed Therapeutics Using Pediatric Patient-Derived Nasal Epithelial Cell Models

Functional profiling of CFTR-directed therapeutics offers the potential to provide significant benefits to young people with cystic fibrosis (CF). However, the development of 2D airway epithelial cell models for individual response tests in CF children remains a central task. The objective of this study was to determine the utility of EpiX^TM technology for expansion of nasal epithelial cells for use in electrophysiological CFTR function measurements. An initial harvest of as few as 20,000 cells was sufficient to expand up to 50 million cells that were used to generate air-liquid interface (ALI) cultures for ion transport studies with the Ussing assay. CFTR function was assessed by measuring responses to forskolin and the CFTR potentiator VX-770 (ivacaftor) in ALI cultures generated from passage 3 and 4 cells. Short-circuit current (Isc) measurements of blocked CFTR currents (ΔI_CFTRinh) discriminated CFTR function between healthy control (wild type, WT) and patients with intermediate (F508del/R117H-7T: 56% WT) and severe (F508del/F508del: 12% WT) CF disease. For the mixed genotypes, CFTR activity for F508del/c.850dupA was 12% WT, R334W/406-1G>A was 24% WT, and CFTRdele2,3(21 kb)/CFTRdele2,3(21 kb) was 9% WT. The CFTR correctors VX-809 (lumacaftor) and VX-661 (tezacaftor) significantly increased CFTR currents for F508del/R117H to 73 and 67% WT, respectively. Cultures with the large deletion mutation CFTRdele2,3(21 kb) unexpectedly responded to VX-661 treatment (20% WT). Amiloride-sensitive sodium currents were robust and ranged between 20-80 μA/cm² depending on the subject. In addition to characterizing the electrophysiological profile of mutant CFTR activity in cultures for five genotypes, our study exemplifies the promising paradigm of bed-to-bench side cooperation and personalized medicine.

The demographics of adverse outcomes in cystic fibrosis

Understanding variability in cystic fibrosis (CF) health outcomes requires an understanding of factors that go far beyond Cystic Fibrosis Transmembrane Receptor (CFTR) function caused by different gene mutations. Social and environmental factors that influence health have a significant influence on the trajectory of health in CF and in other chronic diseases. In this article, we review demographic factors associated with poorer health outcomes in CF, known and postulated biological mechanisms of these outcomes, and interventions that healthcare teams can implement that may reduce outcome disparities.

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

BACKGROUND

Hispanic subjects with cystic fibrosis (CF) have increased morbidity and mortality than non-Hispanic white subjects. The ethnic disparity in mortality varies by region. Factors influencing pulmonary function vary by both ethnicity and region.

OBJECTIVE

To determine if the ethnic difference in pulmonary function varies by region.

METHODS

This retrospective cohort study compared differences in longitudinal pulmonary function (percent-predicted forced vital capacity [FVC], forced expiratory volume in 1 second [FEV₁ ], forced expiratory flow at 25% to 75% [FEF_25-75 ], FEV₁ /FVC, and FEV₁ decline) between Hispanic and non-Hispanic white subjects with CF by Census region of the United States (West, South, Midwest, and Northeast). Subjects were of ages 6 to 25 years and in the CF Foundation Patient Registry from 2008 to 2013. We used linear mixed effects models with subject-specific slopes and intercepts, adjusting for 14 demographic and clinical variables.

RESULTS

Of 14 932 subjects, 1433 (9.6%) were Hispanic and 13 499 (90.4%) were non-Hispanic white. Hispanic subjects' FEV₁ was 9.0% (8.3%-9.8%) lower than non-Hispanic white subjects in the West, while Hispanic subjects' FEV₁ was only 4.0% (3.0%-5.0%) lower in the Midwest, 4.4% (3.1%-5.7%) lower in the Northeast, and 4.4% (3.2%-5.5%) lower in the South. Similarly, FVC and FEF_25-75 were lower among Hispanic subjects compared to non-Hispanic white subjects in all US regions, with the biggest differences in the West. Only in the West was FEV₁ /FVC significantly lower in Hispanic subjects (-0.019; -0.022 to -0.015). FEV₁ decline was not significantly different between ethnicities in any region.

CONCLUSIONS

In CF, Hispanic subjects have lower pulmonary function than non-Hispanic white subjects in all geographic regions with the largest difference in occurring in the West.

Cystic fibrosis year in review 2017

In this article, we highlight cystic fibrosis (CF) reports published in Pediatric Pulmonology during 2017. We also include articles from a variety of journals that are related or are of special interest to clinicians.