Designing the GALAXY study: Partnering with the cystic fibrosis community to optimize assessment of gastrointestinal symptoms

Presentation, characteristics and management of obstructive intestinal conditions in cystic fibrosis

Objective

Constipation and distal intestinal obstruction syndrome (DIOS) are common gastrointestinal manifestations of cystic fibrosis (CF). The primary aim was to describe the characteristics of constipation and DIOS hospitalisations in a paediatric and adult CF service over a 12-year period. The secondary aims were to determine the proportion of constipation and DIOS presentations which met the European Society for Paediatric Gastroenterology, Hepatology and Nutrition (ESPGHAN) CF Working Group definitions and to describe management strategies of both conditions.

Method

A retrospective study of children and adults with CF who were admitted with a primary diagnosis of constipation or DIOS between 1 January 2011 and 31 December 2022. ESPGHAN definitions for constipation and DIOS were retrospectively applied to all admissions to determine if the primary medical diagnosis met ESPGHAN criteria.

Results

During the 12-year study period, 42 hospitalisations for constipation were recorded in 19 patients, and 33 hospitalisations for DIOS were recorded in 23 patients. 88.10% of constipation episodes met ESPGHAN definitions, compared with 3.0% of DIOS episodes. Constipation and DIOS were primarily treated with polyethylene glycol (PEG). The use of sodium amidotrizoate meglumine enemas was significantly higher in the DIOS group (p=0.045). Those admitted with DIOS were significantly less likely to be recommended a weaning dose of PEG (p=0.018).

Conclusion

Children and adults with CF are more commonly admitted for the management of constipation than DIOS. There is considerable variation in diagnostic and therapeutic practice, and this study highlights the need to enhance the translation and adoption of existing best-practice guidelines.

Remote endpoints for clinical trials in cystic fibrosis: Report from the U.S. CF foundation remote endpoints task force

The COVID-19 pandemic necessitated a rapid shift in clinical research to perform virtual visits and remote endpoint assessments, providing a key opportunity to optimize the use of remote endpoints for clinical trials in cystic fibrosis. The use of remote endpoints could allow more diverse participation in clinical trials while minimizing participant burden but must be robustly evaluated to ensure adequate performance and feasibility. In response, the Cystic Fibrosis Foundation convened the Remote Endpoint Task Force (Supplemental Table 1), a multidisciplinary group of CF researchers with remote endpoint expertise and community members tasked to better understand the current and future use of remote endpoints for clinical research. Here, we describe the current use of remote endpoints in CF clinical research, address key unanswered questions regarding their use and feasibility, and discuss the next steps to determine clinical trial readiness.

The current state of gastrointestinal motility evaluation in cystic fibrosis: a comprehensive literature review

Background and Objective

As life expectancy in cystic fibrosis (CF) has increased over the years, a shift in focus toward extra-pulmonary comorbidities such as gastrointestinal (GI) disease has become a topic of particular importance. Although not well-defined in the current literature, GI dysmotility is thought to significantly contribute to GI symptomatology in the CF population. The objective of this article was to provide a comprehensive review of diagnostic modalities at the disposal of the clinician in the evaluation of patients with CF (pwCF) presenting with GI complaints. Furthermore, we aimed to highlight the available literature regarding utilization of these modalities in CF, in addition to their shortcomings, and emphasize areas within the motility literature where further research is essential.

Methods

A comprehensive review of all available literature in the English language through December 1, 2022 utilizing PubMed was conducted. Our search was limited to GI motility/transit and dysmotility in pwCF. Two researchers independently screened references for applicable articles and extracted pertinent data.

Key Content and Findings

Several diagnostic imaging and manometry options exist in the evaluation of dysmotility; however, the literature is lacking in high-quality, prospective studies to validate such testing in pwCF. Common symptoms experienced and diagnostic motility tools available based on segment of the GI tract as related to pwCF are explored in the current review. Shortcomings in the current literature are identified and future direction to enhance research efforts within the field of CF-related dysmotility is provided.

Conclusions

The influence of CF on GI integrity and motility is far-reaching. Despite improvements in longevity and advancement of pulmonary-specific treatment strategies, further high-quality research targeting the evaluation and management of GI dysmotility in pwCF is needed.

Multicenter prospective study showing a high gastrointestinal symptom burden in cystic fibrosis

BACKGROUND AND AIMS

People with cystic fibrosis (PwCF) suffer from gastrointestinal (GI) symptoms affecting their quality of life (QOL). Despite the relevance of GI symptoms to the overall health of PwCF, a paucity of studies only have comprehensively assessed the prevalence, severity and QOL of GI symptoms in both children and adults with Cystic Fibrosis (CF).

METHODS

Eligible participants ≥2 years of age across 26 US CF centers were followed for 4 weeks. Three validated GI electronic patient-reported outcome measures (ePROMs) with a recall period of 2 weeks and a stool-specific questionnaire were administered weekly over four weeks. Total and domain scores of ePROMs were evaluated overall and in subgroups using linear mixed-effect models.

RESULTS

Of 402 enrolled, 58% were ≥ 18 years of age (52% male). The mean (SD) of the total score for PAC-SYM was 0.52 (0.55), for PAGI-SYM was 0.63 (0.67), and for PAC-QOL was 0.67 (0.55). For specific ePROM questions, prevalence of moderate to very severe symptoms were as follows: straining (20.3%), fullness (18.3%), incomplete bowel movements (17.1%), bloating (16.4%), distension (16.4%), abdominal pain (upper-5.1%, lower-7.5%). Comparing participants ≥18 versus <18, a higher prevalence of bloating (63.7% versus 27.3%), lower abdominal pain (39.8% vs 26.2%), stomach fullness (75.6% versus 56.2%), and abdominal distension (60.2% versus 34.9%) was found. Both age groups reported high treatment dissatisfaction as measured with PAC-QOL, mean 1.39 (95% CI: 1.30, 1.47).

CONCLUSION

GI symptoms were reported in all age ranges irrespective of gender, with higher prevalence observed amongst older and female subgroups. Dissatisfaction with GI targeted treatments were reported in a large proportion of participants despite therapy, highlighting an unmet need for clinical interventions.

CLINICALTRIALS

GOV: NCT03801993.

Emerging Approaches to Monitor and Modify Care in the Era of Cystic Fibrosis Transmembrane Conductance Regulators

As we characterize the clinical benefits of highly effective modulator therapy (HEMT) in the cystic fibrosis (CF) population, our paradigm for treating and monitoring disease continues to evolve. More sensitive approaches are necessary to detect early disease and clinical progression. This article reviews evolving strategies to assess disease control and progression in the HEMT era. This article also explores developments in pulmonary function monitoring, advanced respiratory imaging, tools for the collection of patient-reported outcomes, and their application to profile individual responses, guide therapeutic decisions, and improve the quality of life of people with CF.

Probiotic knowledge of adults with cystic fibrosis is limited but is associated with probiotic use: A cross-sectional survey study

Background: Probiotics are used by people with cystic fibrosis (CF) and other chronic diseases to manage gastrointestinal symptoms. Aim: To describe probiotic knowledge; its relationship with probiotic use, probiotic information sources and factors influencing choice in adults with CF and a general population control group. Methods: A cross-sectional questionnaire study was conducted in adults with CF (n = 205) and Controls (n = 158). Probiotic knowledge was compared between CF and Controls using a knowledge score (maximum 5) based on predefined criteria: (1a) bacteria/microorganism; (1b) live; (2a) administered; (2b) adequate dose and (3) health benefit, using independent samples t-test. Two-way analysis of variance explored knowledge scores between CF and Control and between Ever User and Never User groups. Chi-square and Fisher's exact tests compared knowledge criterion, probiotic sources and influences on probiotic choice between groups. Thematic analysis of open-text responses explored probiotic-related knowledge and influences on probiotic decision making. Results: Knowledge scores (mean ± SD) did not differ between CF (1.70 ± 1.12) and Controls (1.89 ± 0.99), p = 0.13. Probiotic use was associated with knowledge score (p < 0.001). More CF Ever Users than Never Users correctly identified criteria 1a (65% vs. 38%), 1b (16% vs. 0%), 2a (45% vs. 22%) and 3 (73% vs. 42%) (all p < 0.005). CF participants considered 'dairy yoghurt' (69%), 'live cultures' (64%) and 'fermented foods' (37%) as 'all/mostly' probiotic sources. The internet was the commonest source of probiotic-related information. Conclusion: Probiotic knowledge and use were associated in adults with CF. Understanding of probiotic characteristics and sources were limited. Education is needed to help guide patient probiotic decision making.

Community Perspective on Pancreatic Enzyme Replacement Therapy in Cystic Fibrosis

People with cystic fibrosis (CF) and exocrine pancreatic insufficiency must take pancreatic enzyme replacement therapy (PERT) to prevent malnutrition and gastrointestinal (GI) symptoms. Finding better ways to manage GI complaints is a high priority for the CF community. We fielded a survey to assess the perspective of people affected by CF regarding symptoms attributed to and challenges associated with current PERT, to identify factors that affect participation in PERT studies, and to understand attitudes toward an outcome measure that could be an alternative to the coefficient of fat absorption test. Persistent GI symptoms are commonly ascribed to PERT. Minimizing time commitment and maximizing patient safety were factors affecting participation in research. We demonstrate 4 generalizable ways to incorporate patient experience early in the research process to aid in development of new medications and help improve study enrollment.

Association between stool consistency and clinical variables among infants with cystic fibrosis: Findings from the BONUS study

BACKGROUND

Concerns related to stool consistency are common in the first year of life among children with cystic fibrosis (CF). However, normal stool patterns for infants with CF have not been described.

METHODS

Secondary analysis was completed from the previously described BONUS cohort which followed 231 infants with CF through the first 12 months of life. Pain, stool category, stool frequency, feeding type, PERT dose, acid suppression medication, antibiotics usage, stool softener usage and fecal calprotectin were described at 3, 6, and 12 months. Repeated measure ANOVA was used to test the difference in mean stool number. Generalized linear mixed models were used to investigate the relationship between stool characteristics and various factors.

RESULTS

The frequency of constipation was stable throughout the first year of life (10-13%) while watery stool significantly decreased from 21.3% at 3 months to 5.8% at 12 months (p=<0.001). The number of stools at months 6 (mean=2.40) and 12 (mean=2.50) are significantly lower than in month 3 (mean=2.83), p<0.025. Exclusive breast feeding was associated with an increased risk for constipation (OR=2.64  [1.60-4.37], p = 0.002) while exclusive formula feeding and acid suppression was associated with decreased risk for constipation (OR=0.40  [0.26-0.61], p=<0.0001 and OR=0.59  [0.39-0.89], p = 0.01 respectively). Pain was not significantly associated with stool consistency.

CONCLUSION

Stool frequency and consistency evolves in infant with CF in a fashion similar to that reported in non-CF infants over the first year. Constipation was not associated with pain and was less common among infants receiving acid suppression or exclusively formula feeding.

Recent advances in the early treatment of cystic fibrosis: Bridging the gap to highly effective modulator therapy

Highly effective modulator therapy (HEMT) for cystic fibrosis (CF) has been touted as one of the greatest advances to date in CF care. As these therapies are now available for many older children and adults with CF, marked improvement of their nutritional status, pulmonary and gastrointestinal symptoms has been observed. However, most infants and younger children are not current candidates for HEMT due to age and/or cystic fibrosis transmembrane conductance regulator (CFTR) mutation. For these young children, it is essential to provide rigorous monitoring and care to avoid potential disease sequelae while awaiting HEMT availability. The following article highlights recent advances in the care of infants and young children with CF with regard to surveillance and treatment of nutritional, pulmonary, and gastrointestinal disorders. Recent clinical trials in this population are also reviewed.

The Intestinal Microbiome and Cystic Fibrosis Transmembrane Conductance Regulator Modulators: Emerging Themes in the Management of Gastrointestinal Manifestations of Cystic Fibrosis

PURPOSE OF REVIEW

While commonly associated with pulmonary manifestations, cystic fibrosis (CF) is a systemic disease with wide-ranging effects on the gastrointestinal (GI) tract. This article reviews major recent updates in gastroenterological CF care and research.

RECENT FINDINGS

The high burden of GI symptoms in CF has led to recent studies assessing GI-specific symptom questionnaires and scoring systems. Intestinal dysbiosis potentially contributes to gastrointestinal symptoms in patients with CF and an increased risk of gastrointestinal cancers in CF. An increased incidence of colorectal cancer (CRC) has led to CF-specific CRC screening and surveillance recommendations. Pharmacologic therapies targeting specific cystic fibrosis transmembrane conductance regulator (CFTR) mutations have shown promise in treating GI manifestations of CF. New research has highlighted the importance of intestinal dysbiosis in CF. Future studies should assess whether CFTR modulators affect the gut microbiome and whether altering the gut microbiome will impact GI symptoms and GI cancer risk.

Utilization of electronic patient-reported outcome measures in cystic fibrosis research: Application to the GALAXY study

BACKGROUND

The Food and Drug Administration considers patient-reported outcome measures (PROMs) an essential part of clinical research studies for approval of new drugs and new indications for existing drugs. GALAXY evaluated the feasibility of electronic PROMs (ePROMS) to conduct a comprehensive evaluation of gastrointestinal (GI) symptoms in persons with cystic fibrosis (pwCF).

METHODS

Three validated GI ePROMs (PAC-SYM, PAGI-SYM and PAC-QOL) were combined with a Stool-Specific questionnaire to make up the GALAXY ePROMs and administered prospectively across 26 CF centers in the United States. The ePROMs were completed at enrollment visit and then electronically at weeks 1, 2 and 4. PwCF at least 2 years and older were eligible for the study. Reminders were only provided by the mobile application during the study window.

RESULTS

There were 402 participants enrolled in GALAXY. Of those, 169 (42%) were under 18 years old and 193 (48%) were female. The proportion of all follow-up weeks with at least 1 ePROM fully completed was 80%, slightly higher in those ≥18 years of age (82.5%) compared to those <18 years of age (76.5%). When assessing the completion for all 4 ePROMs, the percentage was 77.6%, also higher among those ≥18 year of age (81.5% versus 72.2% for < 18 years of age).

CONCLUSION

Using ePROMs, our study demonstrated that GI symptoms can be feasibly collected with good reproducibility and with minimal involvement of research coordinator time. This mechanism of symptom collection may provide an efficient tool for future CF trials.