The GUTFIT Cohort: Understanding of different gastrointestinal symptoms score variation between Chinese and non-Chinese individuals with functional constipation
Authors: Swarnamali H. , Cree J. , Jiet Lim J. , Jayaprakash R. , Zeng E. , Sharma P. , Shrestha A. , Rosanowski S. , Fraser K. , Butowski N. , Tegetmeyer H. , Young W. , Altermann E. , Nivins S. , Gearry R. , Roy N.C. , Mithen R.F. , Barnett M.P.G. , Milan A.M. 
Published: May 2024

The diagnosis of functional constipation (FC) relies on patient-reported outcomes evaluated as criteria based on the clustering of symptoms. Although the ROME IV criteria for FC diagnosis is relevant for a multicultural population(1), how an individual’s lifestyle, environment and culture may influence the pathophysiology of FC remains a gap in our knowledge. Building on insights into mechanisms underpinning disorders of gut-brain interactions (formerly functional gastrointestinal disorders) in the COMFORT Cohort(2), this study aimed to investigate the differences in gastrointestinal (GI) symptom scores among participants with FC in comparison to healthy controls between Chinese and non-Chinese New Zealanders. The Gastrointestinal Understanding of Functional Constipation In an Urban Chinese and Urban non-Chinese New Zealander Cohort (GUTFIT) study was a longitudinal cohort study, which aimed to determine a comprehensive profile of characteristics and biological markers of FC between Chinese and non-Chinese New Zealanders. Chinese (classified according to maternal and paternal ethnicity) or non-Chinese (mixed ethnicities) adults living in Auckland classified as with or without FC based on ROME IV were enrolled. Monthly assessment (for 3 months) of GI symptoms, anthropometry, quality of life, diet, and biological samples were assessed monthly over March to June 2023. Demographics were obtained through a self-reported questionnaires and GI symptoms were assessed using the Gastrointestinal Symptom Rating Scale (GSRS) and Structured Assessment of Gastrointestinal Symptoms Scale (SAGIS). This analysis is a cross-sectional assessment of patient-reported outcomes of GI symptoms. Of 78 enrolled participants, 66 completed the study (male, n = 10; female, n = 56) and were distributed across: Chinese with FC (Ch-FC; n = 11), Chinese control (Ch-CON; n = 19), non-Chinese with FC (NCh-FC; n = 16), non-Chinese control (NCh-CON; n = 20). Mean (SD) age, body mass index, and waist circumference were 40 ± 9 years, 22.7 ± 2.5 kg/m2, and 78.0 ± 7.6 cm, respectively. Ethnicity did not impact SAGIS domain scores for GI symptoms (Ethnicity x FC severity interaction p>0.05). Yet, the constipation symptoms domain of the GSRS was scored differently depending on ethnicity and FC status (Ethnicity x FC interaction p<0.05). In post hoc comparison, NCh-FC tended to have higher GSRS constipation severity scores than Ch-FC (3.4 ± 1.0 versus 3.8 ± 0.8 /8, p<0.1) Although constipation symptom severity tended to be higher in NCh-FC, on the whole, ethnicity did not explain variation in this cohort. FC status was a more important predictor of GI symptoms scores. Future research will assess differences in symptom burden to explore ethnicity-specific characteristics of FC.