Clinical characteristics and nutritional profiles of children with different irritable bowel syndrome subtypes: a retrospective hospital-based study

Introduction

Irritable bowel syndrome (IBS) is a prevalent functional gastrointestinal disorder in children, marked by recurrent abdominal pain accompanied by alterations in bowel habits, including stool frequency and consistency (1). IBS in children is a frequent cause of chronic abdominal pain and gastrointestinal complaints, often leading to repeated medical visits and impaired quality of life (2,3). The Rome IV criteria provide a standardized framework for classifying IBS in children into constipation-predominant (IBS-C), diarrhea-predominant (IBS-D), mixed (IBS-M), and unclassified (IBS-U) subtypes (4,5). The clinical manifestations of IBS in children often overlap with those of other disorders of gut-brain interaction (DGBI) (6), including functional dyspepsia (7), and differ by IBS subtypes, affecting symptom severity, quality of life (8-10), and treatment response (2,8,11,12).

Emerging evidence suggests that nutritional status, including overweight, obesity (13,14), and malnutrition, may influence the development and clinical course of DGBI (15-19). Previous research has emphasized the importance of recognizing and addressing the risk of malnutrition in children with DGBI (20). Moreover, accumulating evidence suggests that obesity may be associated with DGBI, as childhood obesity and DGBI share several overlapping features (21). Functional constipation has been reported to be associated with both overweight/obesity and undernutrition among children (22). Children with IBS have also been reported to exhibit higher body weight and body fatness, whereas undernutrition and short stature are more frequently observed in other functional gastrointestinal disorders such as functional abdominal pain and functional constipation (20). However, the relationship between nutritional status and IBS in children remains controversial (23). Data on the nutritional characteristics of different IBS subtypes in children remain limited, and few studies have systematically evaluated both the clinical profiles and nutritional status of hospitalized children using the Rome IV criteria.

Hence, this study retrospectively analyzed 478 hospitalized children with IBS over approximately 6 years. We compared the clinical features, nutritional status, and sex-specific differences across IBS subtypes to provide comprehensive insights that may inform individualized evaluation and management of children with IBS. We present this article in accordance with the STROBE reporting checklist (available at https://tp.amegroups.com/article/view/10.21037/tp-2026-1-0111/rc).

Methods

Study population

Children with an initial diagnosis of IBS who were hospitalized at the Children’s Hospital, Zhejiang University School of Medicine between January 2020 and October 2025 were enrolled in this study.

The inclusion criteria were as follows: (I) fulfillment of the Rome IV diagnostic criteria for IBS and hospitalization during the study period and (II) completion of a digestive endoscopic examination, including upper gastrointestinal endoscopy (gastroscopy) and colonoscopy.

The exclusion criteria were as follows: (I) failure to meet the Rome IV diagnostic criteria; (II) presence of organic gastrointestinal diseases, such as inflammatory bowel disease or peptic ulcer disease; (III) a previous diagnosis of IBS and prior treatment at another medical institution; (IV) absence of a digestive endoscopic examination; and (V) incomplete clinical data.

Data collection

Upon admission, all eligible patients underwent standardized clinical interviews. Information was collected regarding the presence of abdominal pain, changes in bowel movement frequency or stool consistency, and whether abdominal pain was relieved after defecation. Additional data included potential aggravating factors, occurrence of abdominal pain in the early morning or at night, its relationship with food intake, and overall tolerability of pain. “Cold and irritant foods” refer to foods that may stimulate the gastrointestinal tract, such as cold beverages, spicy foods, and other foods commonly associated with gastrointestinal discomfort. Patients and their caregivers were also asked regarding their accompanying symptoms.

Data on general characteristics, including sex, age, disease duration, mode of delivery, gestational age at birth, picky eating habits, presence of siblings, family history of IBS, self-reported food allergies, psychiatric comorbidities, and history of abdominal surgery, were collected. Clinical manifestations were documented based on symptom descriptions provided by the patients and their caregivers upon admission. The laboratory and endoscopic findings were recorded.

Nutritional assessment

Height and weight were measured on the day of admission using a medical height and weight scale (model TB-QD501-300; Hangzhou Qida Medical Technology Co., Ltd., Hangzhou, China), and body mass index (BMI) was calculated. The BMI-for-age Z-score (BAZ) and height-for-age Z-score (HAZ) were calculated using World Health Organization (WHO) AnthroPlus software (version 1.0.4). Obesity was defined as BAZ ≥2 according to the WHO growth reference for children aged 5–19 years. Malnutrition severity was classified based on BAZ values ≤−1.0 (24). In this study, malnutrition refers to undernutrition, while obesity was analyzed separately.

Ethical statement

This study was conducted in accordance with the Declaration of Helsinki and its subsequent amendments. This study was approved by the Ethics Committee of Children’s Hospital, Zhejiang University School of Medicine (No. 2025-IRB-0247-P-01), and the need for informed consent was waived because this was a retrospective analysis of anonymized clinical data. All methods were performed according to relevant guidelines.

Statistical analysis

Statistical analyses were conducted using SPSS 29.0.1.0. The normality and homogeneity of variance were assessed for all continuous variables. Continuous variables are expressed as mean ± standard deviation (SD) for normally distributed data and as median (25^th–75^th percentiles) for non-normally distributed data. Categorical variables are presented as numbers and percentages. Depending on the distributional characteristics, intergroup differences were examined using one-way analysis of variance followed by Tukey’s post-hoc test, or the Kruskal-Wallis H test with Dunn-Bonferroni adjustments for multiple comparisons. Categorical variables were compared using the χ² test or Fisher’s exact test. Pairwise categorical comparisons employed 2×2 χ² or Fisher’s exact tests, with Bonferroni-adjusted significance levels of P<0.02 for three-group comparisons and P<0.008 for four-group comparisons. All analyses were two-tailed, with P<0.05 considered statistically significant for overall tests.

Results

Baseline clinical data of hospitalized children with IBS subtypes

A total of 478 children diagnosed with IBS were enrolled in the study (Figure 1), including 204 girls (42.68%) and 274 boys (57.32%), with a mean age of 12.29±2.19 years. Among the hospitalized children with IBS, IBS-D was the predominant subtype (n=296, 61.92%). A significantly higher proportion of male patients was observed in the IBS-D group than in the other three subtypes (n=197, 66.55%; P<0.008). Age differed significantly among the four IBS subtypes (χ²=4.16, P=0.006). Post hoc comparisons showed that children with IBS-D were significantly older than those with IBS-C (P<0.008), whereas no significant differences were observed among the other subtype pairs. No statistically significant differences were detected among the four subtypes of children with IBS in terms of disease duration, mode of delivery, gestational age at birth, picky eating behavior, presence of siblings, family history of IBS, self-reported food allergies, psychiatric comorbidities, or history of abdominal surgery (all P>0.05). The diagnostic profile of the enrolled children is presented in Table 1.

Figure 1 Flow diagram of patient selection for the retrospective hospital-based study of children with IBS. IBS, irritable bowel syndrome; IBS-C, constipation-predominant irritable bowel syndrome; IBS-D, diarrhea-predominant irritable bowel syndrome; IBS-M, mixed-type irritable bowel syndrome; IBS-U, unclassified irritable bowel syndrome.

Clinical manifestations in hospitalized children with IBS

In addition to abdominal pain, children hospitalized for IBS frequently presented with concurrent upper and lower gastrointestinal symptoms (Table 2). Cold and irritant food consumption-induced symptom aggravation and sleep disturbances were significantly different among the four groups (P=0.03 and P=0.009, respectively). Children with IBS-C were significantly more prone to experiencing sleep disturbances than those with IBS-D and IBS-U (P<0.008). No statistically significant differences were observed among the four IBS subtypes in terms of the remaining symptoms (all P>0.05). Colonoscopy revealed no significant structural abnormalities in any of the patients. Furthermore, gastroscopy results revealed no significant differences among the different subtypes of IBS in the incidence of Helicobacter pylori gastritis or bile reflux gastropathy (all P>0.05).

Nutritional status of hospitalized children with different IBS subtypes

The nutritional status of hospitalized children with different IBS subtypes is shown in Table 3. BAZ and HAZ differed significantly among the four groups (P=0.002 and P=0.003, respectively). Children with IBS-D had significantly higher HAZ and BAZ than IBS-C patients (P<0.02), differences among the remaining subtypes were not significant. Among the laboratory measures, hemoglobin levels varied significantly across the subtypes (F=18.13, P<0.001). Children with IBS-D had the highest median hemoglobin concentrations. By contrast, no significant differences were observed in serum total protein, serum albumin, or prealbumin levels among the IBS subtypes (all P>0.05).

Differences in baseline characteristics and clinical presentations among children with varying nutritional status

Among the enrolled patients, 74 were classified as having obesity, 292 as having normal weight, and 112 as having malnutrition based on BAZ (Table 4). The proportion of male patients was significantly higher in the obesity group than in the normal weight (77.03% vs. 53.42%) and malnutrition groups (77.03% vs. 54.46%) (χ²=13.93, P<0.001). Disease duration did not differ significantly among groups (χ²=9.53, P=0.15). Subtype distribution differs significantly between groups (χ²=16.01, P=0.01). Picky eating (preference for meat) was more frequently observed in malnourished patients than in those with normal weight (19.64% vs. 8.56%). The number of patients with psychiatric comorbidities showed a statistically significant difference overall among the three groups (χ²=6.12, P=0.047). The prevalence of psychiatric comorbidities was significantly higher in children with abnormal nutritional status (including malnutrition and obesity) than in those with normal nutritional status (χ²=5.90, P=0.02). Decreased appetite was most common in the malnutrition group (64.29%) and was significantly greater than in the remaining groups (χ²=18.76, P<0.001). The differences in other baseline characteristics and clinical manifestations among the three nutritional groups showed no significant differences (all P>0.05).

Sex-specific variations in nutritional status across IBS subtypes

Subsequent analyses examined sex-specific differences in nutritional status across IBS subtypes (Table 5). Among the children with IBS-D, male patients exhibited significantly higher BAZ values than female patients (Z=2.76, P=0.006). The prevalence of obesity was consistently and significantly higher in boys than in girls (24.37% vs. 11.11%, P=0.007). However, no significant sex-related differences were observed in HAZ or the prevalence of malnutrition among children with IBS-D (P>0.05). By contrast, no statistically significant sex-based differences in BAZ, HAZ, obesity, or malnutrition were identified among the IBS-C, IBS-M, or IBS-U subtypes (all P>0.05).

Discussion

We analyzed the demographic, clinical, and nutritional profiles of children hospitalized with IBS at our institution between January 2020 and October 2025. By comparing these features among different subtypes of IBS, this study offers clinically relevant insights that may guide a more accurate diagnosis and tailored management of children with IBS.

IBS-D was the predominant subtype among hospitalized children with IBS (61.92%). Previous epidemiological studies have shown substantial geographic variations in the distribution of IBS subtypes. Hospital- and school-based studies from Turkey (25) and Italy (26) have reported IBS-C as the most prevalent subtype, whereas studies in Nigeria (27) and South Korea (28) have identified IBS-M as the dominant subtype. By contrast, a school-based study in Sri Lanka has reported a relatively even distribution of IBS-D, IBS-C, and IBS-M (12). Studies in the United States have generally reported IBS-C as the most common subtype (29), whereas investigations in Chinese adult outpatient populations have consistently identified IBS-D as predominant (30). Because our cohort comprised exclusively of hospitalized children rather than a community-based population, these findings did not reflect population-level epidemiological patterns. The predominance of IBS-D in this cohort may reflect the greater functional impairment associated with diarrhea as well as differences in health-seeking behavior, whereby caregivers may be more likely to pursue hospital-based evaluation for diarrhea-related symptoms than for constipation or mixed bowel habits. In this study, significant differences in sex and age distributions were observed among the IBS subtypes, with a marked male predominance in the IBS-D group (66.55%). Previous studies on sex differences in IBS in children have reported inconsistent findings, with some showing a higher prevalence in girls (3,12,27,31,32), particularly for IBS-C (12), whereas others have reported no significant differences (29,33,34). By contrast, population-based studies in Japanese adolescent and adult IBS cohorts have identified IBS-D as being more common in men than in women (35), consistent with our results. These variations may reflect differences in study design, subtype classification, or healthcare utilization, and sex hormones may contribute to sex-related differences in IBS (36), although pediatric-specific mechanisms remain unclear. A systematic review has indicated that IBS is more prevalent in children aged 8–12 years and that our cohort largely fell within this high-risk age range. Although the mean age differed significantly among IBS subtypes, the absolute differences were small and may reflect sampling variation (3).

In our study, most clinical characteristics and comorbidities were largely comparable across the IBS subtypes. No significant differences were observed among the subtypes with respect to disease duration, perinatal history, family history, selective eating behaviors, or psychiatric comorbidities, suggesting a relatively homogeneous clinical background of IBS in children. In addition, endoscopic examinations revealed no structural abnormalities across the subtypes, further supporting the functional nature of IBS. In summary, IBS subtype classification in children may primarily reflect differences in symptom presentation rather than the underlying disease background. Previous studies on the clinical characteristics of IBS subtypes in children have yielded inconsistent results. Some studies have reported no differences in symptoms or psychological comorbidities among the subtypes (9), whereas others have indicated a lower quality of life in individuals with IBS-D and IBS-M than in those with IBS-C (37). Children with IBS generally exhibit more intestinal and extraintestinal symptoms than healthy controls (12), and abdominal pain alone is insufficient to distinguish subtypes (29). Sleep disturbances are also common (38), with evidence linking IBS to delayed sleep phases and poor sleep quality (35). In line with this, sleep disturbances and food-triggered symptom exacerbations differed across the subtypes in our study, with children with IBS-C being more affected. As we only assessed the subjective sleep impact, future studies should use validated tools such as the Children’s Sleep Habits Questionnaire (39) to better evaluate sleep quality and guide subtype-specific management strategies.

The analysis revealed that children with IBS-D exhibited higher HAZ and BAZ than those with IBS-C, suggesting that IBS-C may be associated with a greater risk of growth impairment. Studies have shown that the prevalence of overweight and obesity is higher among children with DGBI than among healthy controls (40). Similar trends have been observed in adults, where overweight and obesity are more common in individuals with IBS (41), and the prevalence of IBS is also higher in those with obesity (42). Compared to children without obesity, those with obesity are at a greater risk of developing DGBI, including IBS-C and IBS-D (43). Functional constipation in children has been associated with both overweight/obesity and undernutrition in Asian countries (22), whereas research specifically focusing on the IBS-C subtype remains limited. The potential mechanisms include chronic appetite reduction, dietary restriction, avoidance of defecation, and altered gut function in children with IBS-C. Despite significant differences in anthropometric indices, no significant differences were observed in serum total protein, albumin, or prealbumin levels among IBS subtypes, indicating that single laboratory indicators cannot adequately reflect the nutritional status of children with IBS and that a comprehensive nutritional assessment is warranted.

Furthermore, children with abnormal nutritional status (malnutrition or obesity) had a significantly higher prevalence of psychiatric comorbidities than those with a normal nutritional status. IBS, a disorder marked by abnormalities in the gut-brain interaction, is frequently accompanied by various comorbidities, including anxiety, depression, and other psychological disorders, particularly in children (44). Children with malnutrition were more likely to exhibit decreased appetite and selective eating behaviors, such as a preference for meat, which may further exacerbate their nutritional imbalance. These findings underscore the bidirectional relationship between nutritional status and psychological health in children with IBS, highlighting the need for a comprehensive approach to manage both nutritional and mental health in these patients.

These findings demonstrated sex-specific differences in nutritional outcomes among children with IBS-D. Boys had a significantly higher BAZ and greater prevalence of obesity than girls, whereas no sex-based differences were observed in the other IBS subtypes. This may be partially explained by previous findings that individuals with overweight generally have faster colonic and rectosigmoid transit times, leading to more frequent bowel movements (45). Nonetheless, the relationships among sex, IBS subtypes, and BAZ in pediatric populations warrant further investigation in studies with larger sample sizes and indicate that male children with IBS-D may benefit from earlier monitoring and targeted interventions for weight management.

This study enrolled participants according to the Rome IV criteria and classified children with IBS into specific subtypes. In addition, we used retrospectively collected standardized clinical records from a large pediatric hospital in China rather than relying on self-administered questionnaires. To our knowledge, this study represents a relatively comprehensive retrospective analysis of clinical characteristics and nutritional status among Chinese children with IBS. However, because this study was conducted in a hospital setting and included only hospitalized children, the findings may not be fully generalizable to children with IBS in the community. In addition, lactose intolerance was not systematically assessed because of the retrospective study design and the absence of standardized diagnostic testing in the available medical records, which may have influenced the interpretation of gastrointestinal symptoms. Future research should involve multicenter cohorts and incorporate more comprehensive nutritional assessments, such as body composition analysis and dietary intake quantification, to characterize sex- and subtype-specific variations more accurately in the clinical presentation and nutritional status among children with IBS.

Conclusions

The management of children with IBS should extend beyond the assessment of abdominal pain and bowel habits to include careful evaluation of nutritional status, sleep quality, and psychological comorbidities. Differences across IBS subtypes and between sexes suggest distinct nutritional and psychological risk profiles, underscoring the need for individualized and multidisciplinary management strategies for children with IBS.

Acknowledgments

We gratefully thank the Director of Pediatric Evidence-Based Medical and Clinical Research Laboratory, Dr. Guannan Bai, for the great support in terms of methodology and data analysis.

Footnote

Reporting Checklist: The authors have completed the STROBE reporting checklist. Available at https://tp.amegroups.com/article/view/10.21037/tp-2026-1-0111/rc

Data Sharing Statement: Available at https://tp.amegroups.com/article/view/10.21037/tp-2026-1-0111/dss

Peer Review File: Available at https://tp.amegroups.com/article/view/10.21037/tp-2026-1-0111/prf

Funding: The study was supported by the National Key Research and Development Program of China (Nos. 2023YFC2706500 and 2023YFC2706504).

Conflicts of Interest: All authors have completed the ICMJE uniform disclosure form (available at https://tp.amegroups.com/article/view/10.21037/tp-2026-1-0111/coif). The authors have no conflicts of interest to declare.

Ethical Statement: The authors are accountable for all aspects of the work in ensuring that questions related to the accuracy or integrity of any part of the work are appropriately investigated and resolved. This study was conducted in accordance with the Declaration of Helsinki and its subsequent amendments. This study was approved by the Ethics Committee of Children’s Hospital, Zhejiang University School of Medicine (No. 2025-IRB-0247-P-01), and the need for informed consent was waived because this was a retrospective analysis of anonymized clinical data. All methods were performed according to relevant guidelines.

Open Access Statement: This is an Open Access article distributed in accordance with the Creative Commons Attribution-NonCommercial-NoDerivs 4.0 International License (CC BY-NC-ND 4.0), which permits the non-commercial replication and distribution of the article with the strict proviso that no changes or edits are made and the original work is properly cited (including links to both the formal publication through the relevant DOI and the license). See: https://creativecommons.org/licenses/by-nc-nd/4.0/.

References

1. Gordon M, Groen J, Sinopoulou V, et al. European and North American guidelines for treating irritable bowel syndrome and functional abdominal pain in childhood: a guide for health-care professionals. Lancet Child Adolesc Health 2025;9:808-16. [Crossref] [PubMed]
2. Friesen CA, Rosen JM, Schurman JV. Prevalence of overlap syndromes and symptoms in pediatric functional dyspepsia. BMC Gastroenterol 2016;16:75. [Crossref] [PubMed]
3. Devanarayana NM, Rajindrajith S. Irritable bowel syndrome in children: Current knowledge, challenges and opportunities. World J Gastroenterol 2018;24:2211-35. [Crossref] [PubMed]
4. Thapar N, Benninga MA, Crowell MD, et al. Paediatric functional abdominal pain disorders. Nat Rev Dis Primers 2020;6:89. [Crossref] [PubMed]
5. Drossman DA, Hasler WL. Rome IV-Functional GI Disorders: Disorders of Gut-Brain Interaction. Gastroenterology 2016;150:1257-61. [Crossref] [PubMed]
6. Barbara G, Aziz I, Ballou S, et al. Rome Foundation Working Team Report on overlap in disorders of gut-brain interaction. Nat Rev Gastroenterol Hepatol 2025;22:228-51. [Crossref] [PubMed]
7. Colombo JM, Deacy AD, Schurman JV, et al. Heartburn in children and adolescents in the presence of functional dyspepsia and/or irritable bowel syndrome correlates with the presence of sleep disturbances, anxiety, and depression. Medicine (Baltimore) 2021;100:e25426. [Crossref] [PubMed]
8. Ohlsson B. Extraintestinal manifestations in irritable bowel syndrome: A systematic review. Ther Adv Gastroenterol 2022;15:17562848221114558. [Crossref] [PubMed]
9. Rey de Castro NG, Miller V, Carruthers HR, et al. Irritable bowel syndrome: a comparison of subtypes. J Gastroenterol Hepatol 2015;30:279-85. [Crossref] [PubMed]
10. Singh P, Staller K, Barshop K, et al. Patients with irritable bowel syndrome-diarrhea have lower disease-specific quality of life than irritable bowel syndrome-constipation. World J Gastroenterol 2015;21:8103-9. [Crossref] [PubMed]
11. de Bruijn CMA, Geijtenbeek A, Browne PD, et al. Children with functional gastrointestinal disorders with and without co-existing nausea: A comparison of clinical and psychological characteristics. Neurogastroenterol Motil 2023;35:e14591. [Crossref] [PubMed]
12. Rajindrajith S, Devanarayana NM. Subtypes and Symptomatology of Irritable Bowel Syndrome in Children and Adolescents: A School-based Survey Using Rome III Criteria. J Neurogastroenterol Motil 2012;18:298-304. [Crossref] [PubMed]
13. Malaty HM, Abudayyeh S, Fraley K, et al. Recurrent abdominal pain in school children: effect of obesity and diet. Acta Paediatr 2007;96:572-6. [Crossref] [PubMed]
14. Phatak UP, Pashankar DS. Prevalence of functional gastrointestinal disorders in obese and overweight children. Int J Obes (Lond) 2014;38:1324-7. [Crossref] [PubMed]
15. Song SW, Park SJ, Kim SH, et al. Relationship between irritable bowel syndrome, worry and stress in adolescent girls. J Korean Med Sci 2012;27:1398-404. [Crossref] [PubMed]
16. Fifi AC, Velasco-Benitez C, Saps M. Functional Abdominal Pain and Nutritional Status of Children. A School-Based Study. Nutrients 2020;12:2559.
17. Nwosu BU, Maranda L, Candela N. Vitamin D status in pediatric irritable bowel syndrome. PLoS One 2017;12:e0172183. [Crossref] [PubMed]
18. Khayyatzadeh SS, Kazemi-Bajestani SMR, Mirmousavi SJ, et al. Dietary behaviors in relation to prevalence of irritable bowel syndrome in adolescent girls. J Gastroenterol Hepatol 2018;33:404-10. [Crossref] [PubMed]
19. Roczniak W, Szymlak A, Mazur B, et al. Nutritional Status and Selected Adipokines in Children with Irritable Bowel Syndrome. Nutrients 2022;14:5282. [Crossref] [PubMed]
20. Pawłowska K, Umławska W, Iwańczak B. A Link between Nutritional and Growth States in Pediatric Patients with Functional Gastrointestinal Disorders. J Pediatr 2018;199:171-7. [Crossref] [PubMed]
21. Calcaterra V, Cena H, Loperfido F, et al. Functional Gastrointestinal Disorders and Childhood Obesity: The Role of Diet and Its Impact on Microbiota. Nutrients 2024;17:123. [Crossref] [PubMed]
22. Lazarus G, Junaidi MC, Oswari H. Relationship of Functional Constipation and Growth Status: A Systematic Review and Meta-Analysis. J Pediatr Gastroenterol Nutr 2022;75:702-8. [Crossref] [PubMed]
23. Kim CY, Hyun JH, Ryoo E. Functional Gastrointestinal Disorders and Abdominal Visceral Fat in Children and Adolescents. Pediatr Gastroenterol Hepatol Nutr 2023;26:338-45. [Crossref] [PubMed]
24. Becker P, Carney LN, Corkins MR, et al. Consensus statement of the Academy of Nutrition and Dietetics/American Society for Parenteral and Enteral Nutrition: indicators recommended for the identification and documentation of pediatric malnutrition (undernutrition). Nutr Clin Pract 2015;30:147-61. [Crossref] [PubMed]
25. Karabulut GS, Beşer OF, Erginöz E, et al. The Incidence of Irritable Bowel Syndrome in Children Using the Rome III Criteria and the Effect of Trimebutine Treatment. J Neurogastroenterol Motil 2013;19:90-3. [Crossref] [PubMed]
26. Giannetti E, de’Angelis G, Turco R, et al. Subtypes of irritable bowel syndrome in children: prevalence at diagnosis and at follow-up. J Pediatr 2014;164:1099-1103.e1. [Crossref] [PubMed]
27. Adeniyi OF, Adenike Lesi O, Olatona FA, et al. Irritable bowel syndrome in adolescents in Lagos. Pan Afr Med J 2017;28:93. [Crossref] [PubMed]
28. Son YJ, Jun EY, Park JH. Prevalence and risk factors of irritable bowel syndrome in Korean adolescent girls: a school-based study. Int J Nurs Stud 2009;46:76-84. [Crossref] [PubMed]
29. Self MM, Czyzewski DI, Chumpitazi BP, et al. Subtypes of irritable bowel syndrome in children and adolescents. Clin Gastroenterol Hepatol 2014;12:1468-73. [Crossref] [PubMed]
30. Yao X, Yang YS, Cui LH, et al. Subtypes of irritable bowel syndrome on Rome III criteria: a multicenter study. J Gastroenterol Hepatol 2012;27:760-5. [Crossref] [PubMed]
31. Kesuma Y, Sekartini R, Timan IS, et al. Irritable bowel syndrome in Indonesian adolescents. J Pediatr (Rio J) 2021;97:197-203. [Crossref] [PubMed]
32. Zhu X, Chen W, Zhu X, et al. A cross-sectional study of risk factors for irritable bowel syndrome in children 8-13 years of age in suzhou, china. Gastroenterol Res Pract 2014;2014:198461. [Crossref] [PubMed]
33. Lu PL, Velasco-Benítez CA, Saps M. Sex, Age, and Prevalence of Pediatric Irritable Bowel Syndrome and Constipation in Colombia: A Population-based Study. J Pediatr Gastroenterol Nutr 2017;64:e137-41. [Crossref] [PubMed]
34. Zheng S, Fu W, Zhou J, et al. Prevalence and related factors of irritable bowel syndrome among middle-school students in areas affected by Wenchuan Earthquake: an epidemiological study. J Clin Gastroenterol 2012;46:345-6. [Crossref] [PubMed]
35. Yamamoto R, Kaneita Y, Osaki Y, et al. Irritable bowel syndrome among Japanese adolescents: A nationally representative survey. J Gastroenterol Hepatol 2015;30:1354-60. [Crossref] [PubMed]
36. Ruiz-González D, Cavero-Redondo I, Hernández-Martínez A, et al. Comparative efficacy of exercise, diet and/or pharmacological interventions on BMI, ovulation, and hormonal profile in reproductive-aged women with overweight or obesity: a systematic review and network meta-analysis. Hum Reprod Update 2024;30:472-87. [Crossref] [PubMed]
37. Kibune Nagasako C, Garcia Montes C, Silva Lorena SL, et al. Irritable bowel syndrome subtypes: Clinical and psychological features, body mass index and comorbidities. Rev Esp Enferm Dig 2016;108:59-64. [Crossref] [PubMed]
38. Zhou HQ, Yao M, Chen GY, et al. Functional gastrointestinal disorders among adolescents with poor sleep: a school-based study in Shanghai, China. Sleep Breath 2012;16:1211-8. [Crossref] [PubMed]
39. Deng YJ, Lin T, Li W, et al. Reliability and validity of the revised Chinese version of the Children’s Sleep Habits Questionnaire (CSHQ-CH-R). World J Pediatr 2025;21:1163-74. [Crossref] [PubMed]
40. Galai T, Moran-Lev H, Cohen S, et al. Higher prevalence of obesity among children with functional abdominal pain disorders. BMC Pediatr 2020;20:193. [Crossref] [PubMed]
41. Purssell H, Whorwell PJ, Athwal VS, et al. Non-alcoholic fatty liver disease in irritable bowel syndrome: More than a coincidence? World J Hepatol 2021;13:1816-27. [Crossref] [PubMed]
42. Pugliese G, Muscogiuri G, Barrea L, et al. Irritable bowel syndrome: a new therapeutic target when treating obesity? Hormones (Athens) 2019;18:395-9. [Crossref] [PubMed]
43. Kiyak U, Urganci N, Usta M. Assesment of functional gastrointestinal diseases in obese children. Eur J Pediatr 2023;182:4949-55. [Crossref] [PubMed]
44. Zamani M, Alizadeh-Tabari S, Zamani V. Systematic review with meta-analysis: the prevalence of anxiety and depression in patients with irritable bowel syndrome. Aliment Pharmacol Ther 2019;50:132-43. [Crossref] [PubMed]
45. Sadik R, Björnsson E, Simrén M. The relationship between symptoms, body mass index, gastrointestinal transit and stool frequency in patients with irritable bowel syndrome. Eur J Gastroenterol Hepatol 2010;22:102-8. [Crossref] [PubMed]