, Masakazu Nagahori3
, Tadakazu Hisamatsu4
, Taku Kobayashi5
, Teppei Omori6
, Jimmy K. Limdi7,8
, John T. McLaughlin7,8
, Shu-Chen Wei9
, Jovelle Fernandez10
, Shunichi Fukuhara1,2,11
, Katsuyoshi Matsuoka12
1Section of Clinical Epidemiology, Department of Community Medicine, Graduate School of Medicine, Kyoto University, Kyoto, Japan
2Center for Innovative Research for Communities and Clinical Excellence (CiRC2LE), Fukushima Medical University, Fukushima, Japan
3Clinical Research Center, Tokyo Medical and Dental University Hospital, Tokyo, Japan
4Department of Gastroenterology and Hepatology, Kyorin University School of Medicine, Tokyo, Japan
5Center for Advanced IBD Research and Treatment, Kitasato University Kitasato Institute Hospital, Tokyo, Japan
6Institute of Gastroenterology, Tokyo Women’s Medical University, Tokyo, Japan
7Department of Gastroenterology, Northern Care Alliance NHS Foundation Trust, Greater Manchester, UK
8Division of Diabetes, Endocrinology & Gastroenterology, Faculty of Biology, Medicine and Health, University of Manchester, Manchester Academic Health Sciences Centre, Manchester, UK
9Department of Internal Medicine, National Taiwan University Hospital, Taipei, Taiwan
10Japan Medical Office, Takeda Pharmaceutical Company Limited, Tokyo, Japan
11Department of Health Policy and Management, Johns Hopkins Bloomberg School of Public Health, Baltimore, MD, USA
12Division of Gastroenterology and Hepatology, Department of Internal Medicine, Toho University Sakura Medical Center, Sakura, Japan
© 2026 Korean Association for the Study of Intestinal Diseases.
This is an Open Access article distributed under the terms of the Creative Commons Attribution Non-Commercial License (http://creativecommons.org/licenses/by-nc/4.0/) which permits unrestricted non-commercial use, distribution, and reproduction in any medium, provided the original work is properly cited.
| Characteristic | All patients (n = 911) |
|---|---|
| Age (yr), median (IQR) | 44 (34–55) |
| Sex, No. (%) | |
| Male | 492 (54.0) |
| Female | 419 (46.0) |
| BMI (kg/m2), median (IQR) |
21.7 (20.1–24.2) |
| Disease duration (yr), median (IQR) |
9 (5–15) |
| Relapse within the past year, No. (%) | 196 (21.5) |
| Disease extent, No. (%) | |
| Extensive colitis | 498 (54.7) |
| Left-sided colitis | 225 (24.7) |
| Proctitis | 161 (17.7) |
| Right-sided colitis | 11 (1.2) |
| Unknown | 16 (1.8) |
| Current medication, No. (%) | |
| Oral 5-aminosalicylates | 795 (87.3) |
| Immunomodulators | 221 (24.3) |
| Biologics (TNF-α inhibitors, vedolizumab), tofacitinib | 181 (19.9) |
| ASK-12, median (IQR) |
31 (27.0–34.5) |
| Education, No. (%) |
|
| Graduated from university or college | 574 (63.0) |
| Employment status, No. (%) |
|
| Full-time | 581 (63.8) |
| Part-time | 123 (13.5) |
| Unemployed | 205 (22.5) |
| Living status, No. (%) |
|
| With family | 749 (82.2) |
| Alone | 144 (15.8) |
| With others | 15 (1.6) |
| Limitation of selecting food or drink due to income, No. (%) |
113 (12.4) |
| Annual income (JPY), No. (%) |
|
| < 3 million | 104 (11.4) |
| 3 to < 5 million | 218 (23.9) |
| 5 to < 7 million | 205 (22.5) |
| 7 to < 10 million | 187 (20.5) |
| 10 to < 12 million | 85 (9.3) |
| ≥ 12 million | 88 (9.7) |
| Relapse, % (n/N) | Crude |
Multivariable adjusted |
|||
|---|---|---|---|---|---|
| HR (95% CI) | P-value | HR (95% CI) | P-value | ||
| Diet | |||||
| Not avoid | 24.3 (71/292) | Reference | Reference | ||
| Avoid | 26.2 (145/554) | 1.06 (0.80–1.40) | 0.71 | 1.08 (0.81–1.44) | 0.62 |
| Physical exercise | |||||
| Not avoid | 24.1 (195/808) | Reference | Reference | ||
| Avoid | 34.3 (24/70) | 1.50 (0.98–2.30) | 0.06 | 1.58 (1.02–2.44) | 0.04 |
| Work/study/housework | |||||
| Not avoid | 23.1 (106/459) | Reference | Reference | ||
| Avoid | 26.9 (113/420) | 1.13 (0.87–1.48) | 0.35 | 1.14 (0.87–1.50) | 0.34 |
| Total | Crude |
Multivariable adjusted |
|||
|---|---|---|---|---|---|
| β (95% CI) | P-value | β (95% CI) | P-value | ||
| Diet | |||||
| Not avoid | 205 | Reference | Reference | ||
| Avoid | 391 | 0.26 (0.17–0.35) | < 0.001 | 0.22 (0.13–0.32) | < 0.001 |
| Physical exercise | |||||
| Not avoid | 568 | Reference | Reference | ||
| Avoid | 47 | 0.35 (0.19–0.51) | < 0.001 | 0.30 (0.14–0.46) | < 0.001 |
| Work/study/housework | |||||
| Not avoid | 317 | Reference | Reference | ||
| Avoid | 298 | 0.16 (0.08–0.25) | < 0.001 | 0.12 (0.03–0.20) | 0.008 |
Missing data: ASK-12 (n=5), BMI (n=13), disease duration (n=5), education (n=1), living status (n=3), employment status (n=2), income with limiting dietary choices (n=1), and annual income (n=24). IQR, interquartile range; BMI, body mass index; TNF, tumor necrosis factor; ASK-12, Adherence Starts with Knowledge-12; JPY, Japanese yen.
The multivariable Cox regression models included 12 likely confounders: age, sex, smoking, 5-aminosalicylate, immunomodulators, tumor necrosis factor-α inhibitors/tofacitinib/vedolizumab, medication adherence, relapse within the past year, disease duration, employment status, income, and education. The number of patients analyzed was 846 for diet, 878 for physical exercise, and 879 for work/study/housework, based on available data for all variables included in these multivariable analyses. HR, hazard ratio; CI, confidence interval.
QOL was assessed 4 times using the QDIS-1 measure, and a higher QDIS-1 score indicates worse QOL. The baseline standard deviation of the QDIS-1 score in the group not avoiding these lifestyle factors was 0.3 (diet), 0.5 (physical activity), and 0.4 (work/study/housework). The mixed-effects linear regression models included 12 likely confounders: age, sex, smoking, 5-aminosalicylate, immunomodulators, tumor necrosis factor-α inhibitors/tofacitinib/vedolizumab, medication adherence, relapse within the past year, disease duration, employment status, income, and education. The number of patients analyzed was 596 for diet, 615 for physical exercise, and 615 for work/study/housework, based on available data for all variables included in these multivariable analyses. QOL, quality of life; β, regression coefficient; CI, confidence interval; QDIS-1, quality of life disease impact scale-1.
