Disparities in Mortality of Hispanic Patients with Cystic Fibrosis in the United States. A National and Regional Cohort Study

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.

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.

Structural and Social Determinants of Inequitable Environmental Exposures in the United States

American Indian (AI)/Alaskan Natives, African Americans, and Latino Americans have disproportionally high exposure to harmful environmental conditions as a consequence of unjust laws and policies, systemic racism, residential segregation, and discrimination. In this review, we draw connections between historical policies and social movements in the United States' history that have been rooted in racism and classism, leading to social isolation and marginalization of AIs, African Americans, and Latino Americans. We then discuss the structural factors that stem from the aforementioned inequities and that contribute to the inequitable distribution of environmental hazards.

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.

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.

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.

Changing racial and ethnic differences for lung transplantation in cystic fibrosis

BACKGROUND

CFTR modulators, especially (elexacaftor/tezacaftor/ivacaftor), have positively impacted the CF population and quickly decreased LTx numbers. However, no study has investigated if this reduction is universal across all races/ethnicities.

METHODS

Using the UNOS Registry, we explored the frequency/proportions of LTx in WNH and NW (Black, non-Hispanic/Hispanic-Latino/Asian-non Hispanic/American Indian-Alaskan Native-non-Hispanic/Native Hawaiian/Other Pacific Islander-non-Hispanic/Multiracial) in children and adults with CF in the US.

RESULTS

Between 1990 and 2019, the annual mean (±SD) number of LTxs for children with CF was 23.2 (±7.7) compared to 5 in 2020 (p < .001) and in 2021 (p < .001). In adults from 1990 to 2019, the mean (±SD) number of LTxs performed was 144.9 (±73.5), which was significantly higher than 2020 (n = 73; p < .001) and 2021 (n = 45; p < .001). Comparing 1990-2019 to post-2019, the proportion of LTxs performed in both children and adults with CF has decreased from 50.5% (696/1378) to 16.4% (9/55) and from 12.1% (4773/39542) to 2.4% (118/5004), respectively. In WNH pediatric patients, the difference in the percentage of all LTx made up by CF patients between the two eras was 41.2% compared to NW patients where the difference was 11%. Similarly in adults, the difference between the two eras was 10.4% in WNH and 2.4% in NW patients.

CONCLUSIONS

The recent reduction in LTx for the CF population has had less impact on the NW population in the US, so the continuation of optimal referrals for this group is needed.

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.

Take on transplant: human-centered design of a patient education tool to facilitate informed discussions about lung transplant among people with cystic fibrosis

OBJECTIVE

Lung transplant (LTx) saves lives in cystic fibrosis (CF). However, many potential candidates express uncertainty about LTx and die before receiving this treatment. CF guidelines recommend LTx education and clinical discussions well before the need for LTx arises, but limited patient resources exist.

MATERIALS AND METHODS

We engaged people with CF and CF physicians in human-centered design of "Take On Transplant" (TOT), a web-based education tool to prepare patients for LTx discussions. Across 3 phases, needs assessment, design groups, and iterative user testing of TOT, we refined TOT from wireframe prototypes, to an interactive website, to a fully functional intervention ready for clinical trials.

RESULTS

Fifty-five people with CF and 105 physicians identified information needs to prepare for LTx discussions. Design groups (n = 14 participants) then established core requirements: didactic education ("Resource Library"), patient narratives ("CF Stories"), frequently asked questions ("FAQ"), and self-assessment to tailor content ("My CF Stage"). Iterative usability testing (n = 39) optimized the design of CF Stories and prototype layout. We then developed the TOT website and demonstrated feasibility and preliminary efficacy of use through 2-week field testing (n = 9).

DISCUSSION

Our human-centered design process provided guidance for educational tools to serve the evolving needs of potential LTx candidates. Our findings support the process of patient deliberation as a foundation for shared decision-making in CF, and inform educational tools that could potentially translate beyond LTx.

CONCLUSION

TOT fills a critical gap in preparing people with CF for shared decision-making about LTx and may serve as a model for educational tools for other preference-sensitive decisions.

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.

Trends in cystic fibrosis survival over 40 years in South Africa: An observational cohort study

INTRODUCTION

Temporal trends in cystic fibrosis (CF) survival from low-middle-income settings is poorly reported. We describe changes in CF survival after diagnosis over 40 years from a South African (SA) CF center.

METHODS

An observational cohort study of people diagnosed with CF from 1974 to 2019. Changes in age-specific mortality rates from 2000 (vs. before 2000) were estimated using multivariable Poisson regression. Data were stratified by current age < or ≥10 years and models controlled for diagnosis age, sex, ethnicity, genotype, and Pseudomonas aeruginosa (PA) infection. A second analysis explored the association of mortality with weight and forced expiratory volume in 1 s reported as z-scores (FEV1z-scores) at age 5-8 years.

RESULTS

A total of 288 people (52% male; 57% Caucasian; 44% p.Phe508del homozygous) were included (median diagnosis age 0.5 years: Q1, Q3: 0.2, 2.5); 100 (35%) died and 30 (10%) lost to follow-up. Among age >10 years, age-specific mortality from 2000 was significantly lower (adjusted hazard ratio [aHR]: 0.14; 95% confidence interval [CI]: 0.06, 0.29; p < 0.001), but not among age <10 years (aHR: 0.67; 95% CI: 0.28, 1.64; p = 0.383). In children <10 years, Caucasian ethnicity was associated with lower mortality (aHR 0.17; 95% CI: 0.05, 0.63), and longer times since first PA infection with higher mortality (aHR: 1.31; 95% CI: 1.01, 1.68). Mortality was sevenfold higher if FEV1z was <-2.0 at age 5-8 years (aHR: 7.64; 95% CI: 2.58, 22.59).

CONCLUSION

Overall, CF survival has significantly improved in SA from 2000 in people older than 10 years. However, increased risk of mortality persists in young non-Caucasian children, and with FEV1z <-2.0 at age 5-8 years.

Changes in Care during the COVID-19 Pandemic for People with Cystic Fibrosis

Rationale

Cystic fibrosis (CF) centers transitioned to telemedicine during the spring 2020 peak of the coronavirus disease (COVID-19) pandemic.

Objectives

We hypothesized that people with CF (pwCF) with more severe disease would be more likely to be seen in-person.

Methods

We used paired t tests to compare within-subject changes in body mass index (BMI) and percentage predicted forced expiratory volume in one second (FEV₁) and calculated relative risk (RR) to compare pulmonary exacerbations (PEx) between pwCF enrolled in the CF Foundation Patient Registry with at least one in-person clinic visit after March 15 in both 2019 and 2020.

Results

Overall, the proportion of clinical encounters that were in-person clinic visits decreased from 91% in 2019 to a low of 9% in April 2020. Among pwCF seen after March 15 in both 2019 and 2020, the mean (95% confidence interval [CI]) FEV₁ percentage predicted was 1.3% (0.1–2.4) predicted higher in 2020 for children 6 to <12 years of age, and 7.5% (7.1–7.9) predicted higher in 2020 among pwCF ⩾12 years of age eligible for the highly effective CF transmembrane conductance regulator modulator, elexacaftor-tezacaftor-ivacaftor (ETI). There was no difference in FEV₁ percentage predicted for pwCF ⩾12 years of age who were not eligible for ETI. Similarly, the mean (95% CI) BMI was 2.4 (2.0–2.8) percentile higher in 2020 for children 6 to <12 years of age and 5.2 (4.8–5.7) percentile higher in 2020 among children 12 to <18 years of age eligible for ETI. Mean (95% CI) BMI was 1.2 (1.2–1.3) (kg/m²) higher for pwCF ⩾18 years of age eligible for ETI, and 0.2 (0.1–0.3) (kg/m²) higher for pwCF ⩾18 years of age not eligible for ETI. The proportion of in-person clinic visits where any PEx was present was lower in 2020 compared with 2019, 25% compared with 38%, RR 0.82 (0.79–0.86).

Conclusions

The care of pwCF was substantially changed during the spring 2020 peak of the COVID-19 pandemic. Among pwCF seen in-person in both 2019 and 2020 after the spring peak of the COVID-19 pandemic, lung function and BMI were higher in 2020 for children 6 to <12 years of age and pwCF eligible for ETI.

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.

Cystic fibrosis in South Africa: spectrum of disease and determinants of outcome

Introduction

Little is known about cystic fibrosis (CF) in low- to middle-income settings. This study aimed to describe the spectrum and outcomes of CF in South Africa (SA) from the recently established SA CF registry (SACFR).

Methods

Demographic, diagnosis and clinical data were extracted from the SACFR. Cross-sectional univariable and multivariable regression analysis of best forced expiratory volume in 1 s (FEV₁; age≥6 years) and nutrition (all ages) in 2018 was conducted to investigate factors associated with severe lung disease (SLD; FEV₁ ≤3.0 z-score) and undernutrition.

Results

By December 2018, ancestry of 447 individuals included in the SACFR was Caucasian (315; 70%), mixed (87; 19%) and black African (41; 9%). Median diagnosis age was 7.6 months (IQR 2.7-37.1). Genotype was p.Phe508del homozygous (220; 49%); p.Phe508del heterozygous (144; 32%) and neither p.Phe508del or unknown Cystic Fibrosis Transmembrane Conductance Regulator (CFTR) variant in 83 (19%); the second most frequent CFTR variant was 3120+1G>A, common in black Africans. Median age of patients in 2018 was 14.7 years (IQR 7.4-24.4). SLD was independently associated with chronic methicillin-resistant Staphylococcus aureus (MRSA) (adjusted odds ratio( aOR) 16.75; 95% CI 1.74-161.50), undernutrition (aOR 5.20; 95% CI 2.23-12.13) and age (aOR 2.23 per 10 years; 95% CI 1.50-3.31). Undernutrition was associated in univariable analysis with low weight at diagnosis, non-Caucasian ancestry, chronic P. aeruginosa infection and lower socioeconomic status.

Conclusion

Interventions targeting MRSA infection and nutrition are needed to improve CF outcomes in SA. Most people with CF in SA are eligible for highly effective CFTR modulator therapy.

Health Disparities among adults cared for at an urban cystic fibrosis program

BACKGROUND

Evidence is conflicting regarding differential health outcomes in racial and ethnic minorities with cystic fibrosis (CF), a rare genetic disease affecting approximately 28,000 Americans. We performed a cross-sectional analysis of health outcomes in Black/Latinx patients compared with non-Hispanic Caucasian patients cared for in a CF center in New York City. Adult patients enrolled in the CF Foundation Patient Registry at the Columbia University Adult CF Program and seen at least once during 2019 were included. Health metrics were compared between Black/Latinx and non-Hispanic Caucasian patients.

RESULTS

262 patients were eligible. 39 patients (15%) identified as Black/Latinx or non-Hispanic Caucasian. Descriptive statistics are reported with mean (standard deviation). Current age was 35.9 (13.3) years for non-Hispanic Caucasian and 32.0 (9.3) years for Black/Latinx patients (p = 0.087). Age of diagnosis did not differ between groups; 9.56 (15.96) years versus 11.59 (15.8) years for non-Hispanic Caucasian versus Black/Latinx respectively (p = 0.464). Pulmonary function, measured as mean forced expiratory volume in one second (FEV1) was 70.6 (22.5) percent predicted in non-Hispanic Caucasian versus 59.50 (27.9) percent predicted in Black/Latinx patients (p = 0.010). Number of visits to the CF clinic were similar between groups. When controlled for age, gender, co-morbidities, median income, and insurance status, there was a continued association between minority status and lower FEV1.

CONCLUSIONS

Minorities with CF have significantly lower pulmonary function, the major marker of survival, than non-Hispanic Caucasians, even when controlled for a variety of demographic and socioeconomic factors that are known to affect health status in CF. Significant health disparities based on race and ethnicity exist at a single CF center in New York City, despite apparent similarities in access to guideline based care at an accredited CF Center. This data confirms the importance of design of culturally appropriate preventative and management strategies to better understand how to direct interventions to this vulnerable population with a rare disease.

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.

Sex and Gender Differences in Lung Disease

Sex differences in the anatomy and physiology of the respiratory system have been widely reported. These intrinsic sex differences have also been shown to modulate the pathophysiology, incidence, morbidity, and mortality of several lung diseases across the life span. In this chapter, we describe the epidemiology of sex differences in respiratory diseases including neonatal lung disease (respiratory distress syndrome, bronchopulmonary dysplasia) and pediatric and adult disease (including asthma, cystic fibrosis, idiopathic pulmonary fibrosis, chronic obstructive pulmonary disease, lung cancer, lymphangioleiomyomatosis, obstructive sleep apnea, pulmonary arterial hypertension, and respiratory viral infections such as respiratory syncytial virus, influenza, and SARS-CoV-2). We also discuss the current state of research on the mechanisms underlying the observed sex differences in lung disease susceptibility and severity and the importance of considering both sex and gender variables in research studies' design and analysis.

Inequalities and Inequities in Pediatric Respiratory Diseases

Social inequality refers to disparities in society that have the effect of limiting a group's socioeconomic, educational, and intellectual potential. Inequity in health means any limitation to access comprehensive health services that also hinders the achievement of well-being and favorable health outcomes. Strategies for more equitable growth to eradicate global poverty would contribute to reducing health inequities and improve health care outcomes. Coordinated efforts between governments, private sector, families, and interested stakeholders are needed. This article discusses inequality and inequity in pediatric respiratory diseases, the challenges confronted, and the strategies needed to mitigate these disparities.

Promoting emotional wellness in children with cystic fibrosis, Part I: Child and family resilience

Attention should be given to individual and family well-being from a child's first interaction with the medical team and continuing throughout development, especially for families who experience chronic illnesses, such as cystic fibrosis (CF). While much attention has been given to the mental health of people with CF 12 years and older, this paper explores various areas for CF teams to assess and provide additional resources during the first 12 years of a child's life to promote child and family wellness. In this paper, we discuss parental mental health, social determinants of health, adherence/self-care, nutrition, attention to family lifestyle factors, engagement with school and peers, and modulator therapy for this age group of people with CF. This is the first of two companion papers which examines emotional wellness of children during the early years. The second paper examines mental health assessment and intervention for children under 12. Both encourage teams to strive to promote optimal child and family emotional health and wellness, emphasizing holistic health promotion and prevention, early identification, and intervention.

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.

Multi-dimensional clinical phenotyping of a national cohort of adult cystic fibrosis patients

BACKGROUND

Cystic Fibrosis (CF) is a multi-systemic disorder resulting from genetic variation in the Cystic Fibrosis Transmembrane Conductance Regulator (CFTR) gene which can result in bronchiectasis, chronic sinusitis, pancreatic malabsorption, cholestatic liver disease and distal intestinal obstructive syndrome. This study generates multi-dimensional clinical phenotypes that capture the complexity and spectrum of the disease manifestations seen in adult CF patients using statistically robust techniques.

METHODS

Pre-transplant clinical data from adult (age ≥18 years) CF patients (n = 992) seen in six regionally distinct US CF centers between 1/1/2014 and 6/30/2015 were included. Demographic, spirometry, nutritional, microbiological and therapy data were used to generate clusters using the Random Forests statistical-learning and Partitioning around Medoids (PAM) clustering algorithms. Five commonly measured demographic, physiological and nutritional parameters were needed to create the final phenotypes that are highly similar to a regionally matched group of patients from the CF Foundation Patient Registry RESULTS: This approach identified high-risk phenotypes with expected characteristics including high rates of pancreatic insufficiency, diabetes and Pseudomonas aeruginosa colonization. It also identified unexpected populations including a) a male-dominated, well-nourished group with good lung function with a high prevalence of severe genotypes (i.e. 60% subjects had two minimal function CFTR variations), b) and an older, "survivor" phenotype that had high rates of chronic P. aeruginosa infection.

CONCLUSIONS

This study identified recognizable phenotypes that capture the clinical complexity in a statistically robust manner and which may aide in the identification of specific genetic and environmental factors responsible for these disease manifestation patterns.

Pulmonary non-tuberculous mycobacterial infections: current state and future management

Currently, there is a trend of increasing incidence in pulmonary non-tuberculous mycobacterial infections (PNTM) together with a decrease in tuberculosis (TB) incidence, particularly in developed countries. The prevalence of PNTM in underdeveloped and developing countries remains unclear as there is still a lack of detection methods that could clearly diagnose PNTM applicable in these low-resource settings. Since non-tuberculous mycobacteria (NTM) are environmental pathogens, the vicinity favouring host-pathogen interactions is known as important predisposing factor for PNTM. The ongoing changes in world population, as well as socio-political and economic factors, are linked to the rise in the incidence of PNTM. Development is an important factor for the improvement of population well-being, but it has also been linked, in general, to detrimental environmental consequences, including the rise of emergent (usually neglected) infectious diseases, such as PNTM. The rise of neglected PNTM infections requires the expansion of the current efforts on the development of diagnostics, therapies and vaccines for mycobacterial diseases, which at present, are mainly focused on TB. This review discuss the current situation of PNTM and its predisposing factors, as well as the efforts and challenges for their control.

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.

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 2018, part 1

Cystic fibrosis research and case reports were robust in the year 2018. This report summarizes research and cases related to Cystic Fibrosis Transmembrane Conductance Regulator (CFTR) modulator therapies, inflammation and infection, epidemiology and the physiologic, and imaging assessment of disease.

Lung transplant referral for individuals with cystic fibrosis: Cystic Fibrosis Foundation consensus guidelines

OBJECTIVE

Provide recommendations to the cystic fibrosis (CF) community to facilitate timely referral for lung transplantation for individuals with CF.

METHODS

The CF Foundation organized a multidisciplinary committee to develop CF Lung Transplant Referral Consensus Guidelines. Three workgroups were formed: timing for transplant referral; modifiable barriers to transplant; and transition to transplant care. A focus group of lung transplant recipients with CF and spouses of CF recipients informed guideline development.

RESULTS

The committee formulated 21 recommendation statements based on literature review, committee member practices, focus group insights, and in response to public comment. Critical approaches to optimizing access to lung transplant include early discussion of this treatment option, assessment for modifiable barriers to transplant, and open communication between the CF and lung transplant centers.

CONCLUSIONS

These guidelines will help CF providers counsel their patients and may reduce the number of individuals with CF who die without consideration for lung transplant.