| 1. |
- Eijsbouts, C., et al.
(author)
-
Genome-wide analysis of 53,400 people with irritable bowel syndrome highlights shared genetic pathways with mood and anxiety disorders
- 2021
-
In: Nature Genetics. - : Springer Science and Business Media LLC. - 1061-4036 .- 1546-1718. ; 53:11, s. 1543-1552
-
Journal article (peer-reviewed)abstract
- Irritable bowel syndrome (IBS) results from disordered brain–gut interactions. Identifying susceptibility genes could highlight the underlying pathophysiological mechanisms. We designed a digestive health questionnaire for UK Biobank and combined identified cases with IBS with independent cohorts. We conducted a genome-wide association study with 53,400 cases and 433,201 controls and replicated significant associations in a 23andMe panel (205,252 cases and 1,384,055 controls). Our study identified and confirmed six genetic susceptibility loci for IBS. Implicated genes included NCAM1, CADM2, PHF2/FAM120A, DOCK9, CKAP2/TPTE2P3 and BAG6. The first four are associated with mood and anxiety disorders, expressed in the nervous system, or both. Mirroring this, we also found strong genome-wide correlation between the risk of IBS and anxiety, neuroticism and depression (rg > 0.5). Additional analyses suggested this arises due to shared pathogenic pathways rather than, for example, anxiety causing abdominal symptoms. Implicated mechanisms require further exploration to help understand the altered brain–gut interactions underlying IBS. © 2021, The Author(s).
|
|
| 2. |
- Bonfiglio, F., et al.
(author)
-
Female-Specific Association Between Variants on Chromosome 9 and Self-Reported Diagnosis of Irritable Bowel Syndrome
- 2018
-
In: Gastroenterology. - : Elsevier BV. - 0016-5085 .- 1528-0012. ; 155:1, s. 168-179
-
Journal article (peer-reviewed)abstract
- BACKGROUND & AIMS: Genetic factors are believed to affect risk for irritable bowel syndrome (IBS), but there have been no sufficiently powered and adequately sized studies. To identify DNA variants associated with IBS risk, we performed a genome-wide association study (GWAS) of the large UK Biobank population-based cohort, which includes genotype and health data from 500,000 participants. METHODS: We studied 7,287,191 high-quality single nucleotide polymorphisms in individuals who self-reported a doctor's diagnosis of IBS (cases; n = 9576) compared to the remainder of the cohort (controls; n = 336,499) (mean age of study subjects, 40-69 years). Genome-wide significant findings were further investigated in 2045 patients with IBS from tertiary centers and 7955 population controls from Europe and the United States, and a small general population sample from Sweden (n = 249). Functional annotation of GWAS results was carried out by integrating data from multiple biorepositories to obtain biological insights from the observed associations. RESULTS: We identified a genome-wide significant association on chromosome 9q31.2 (single nucleotide polymorphism rs10512344; P = 3.57 x 10(-8)) in a region previously linked to age at menarche, and 13 additional loci of suggestive significance (P < 5.0 x 10(-6)). Sex-stratified analyses revealed that the variants at 9q31.2 affect risk of IBS in women only (P = 4.29 x 10(-10) in UK Biobank) and also associate with constipation-predominant IBS in women (P = .015 in the tertiary cohort) and harder stools in women (P = .0012 in the population-based sample). Functional annotation of the 9q31.2 locus identified 8 candidate genes, including the elongator complex protein 1 gene (ELP1 or IKB-KAP), which is mutated in patients with familial dysautonomia. CONCLUSIONS: In a sufficiently powered GWAS of IBS, we associated variants at the locus 9q31.2 with risk of IBS in women. This observation may provide additional rationale for investigating the role of sex hormones and autonomic dysfunction in IBS.
|
|
| 3. |
- Henstrom, M., et al.
(author)
-
Functional variants in the sucrase-isomaltase gene associate with increased risk of irritable bowel syndrome
- 2018
-
In: Gut. - : BMJ. - 0017-5749 .- 1468-3288. ; 67:2, s. 263-270
-
Journal article (peer-reviewed)abstract
- Objective IBS is a common gut disorder of uncertain pathogenesis. Among other factors, genetics and certain foods are proposed to contribute. Congenital sucraseisomaltase deficiency (CSID) is a rare genetic form of disaccharide malabsorption characterised by diarrhoea, abdominal pain and bloating, which are features common to IBS. We tested sucrase-isomaltase (SI) gene variants for their potential relevance in IBS. Design We sequenced SI exons in seven familial cases, and screened four CSID mutations (p.Val557Gly, p. Gly1073Asp, p.Arg1124Ter and p.Phe1745Cys) and a common SI coding polymorphism (p.Val15Phe) in a multicentre cohort of 1887 cases and controls. We studied the effect of the 15Val to 15Phe substitution on SI function in vitro. We analysed p.Val15Phe genotype in relation to IBS status, stool frequency and faecal microbiota composition in 250 individuals from the general population. Results CSID mutations were more common in patients than asymptomatic controls (p=0.074; OR=1.84) and Exome Aggregation Consortium reference sequenced individuals (p=0.020; OR=1.57). 15Phe was detected in 6/7 sequenced familial cases, and increased IBS risk in case-control and population-based cohorts, with best evidence for diarrhoea phenotypes (combined p=0.00012; OR=1.36). In the population-based sample, 15Phe allele dosage correlated with stool frequency (p=0.026) and Parabacteroides faecal microbiota abundance (p=0.0024). The SI protein with 15Phe exhibited 35% reduced enzymatic activity in vitro compared with 15Val (p<0.05). Conclusions SI gene variants coding for disaccharidases with defective or reduced enzymatic activity predispose to IBS. This may help the identification of individuals at risk, and contribute to personalising treatment options in a subset of patients.
|
|
| 4. |
- Angelison, Leif, et al.
(author)
-
Long-term outcome of infliximab treatment in chronic active ulcerative colitis : a Swedish multicentre study of 250 patients
- 2017
-
In: Alimentary Pharmacology and Therapeutics. - : Wiley-Blackwell Publishing Inc.. - 0269-2813 .- 1365-2036. ; 45:4, s. 519-532
-
Journal article (peer-reviewed)abstract
- Background: Real-life long-term data on infliximab treatment in ulcerative colitis are limited.Aim: To study the long-term efficacy and safety of infliximab in chronic active ulcerative colitis and possible predictors of colectomy and response were also examined.Methods: A retrospective multi-centre study of infliximab treatment in 250 patients with chronic active ulcerative colitis with inclusion criteria: age ≥18 years, ambulatory treated, steroid-dependent or intolerant and/or immunomodulator refractory or intolerant.Results: Steroid-free clinical remission was achieved by 123/250 patients (49.2%) at 12 months and in 126/250 patients at a median follow-up of 2.9 years (50.4%). Primary response at 3 months was achieved by 190/250 (76.0%) patients and associated with a high probability of response 168/190 (88.4%) at 12 months and 143/190 (75.3%) at follow-up. Long-term rate of colectomy in primary responders was 6/190 (3.2%) at 12 months and 27/190 (14.2%) at last follow-up. Failure to achieve response at 3 months was associated with a high risk of subsequent colectomy, 29/60 (48.3%) at 12 months and 41/60 (68.3%) at follow-up. Response at 12 months was associated with a low risk of subsequent colectomy, 14/181 (7.7%) compared with non-response 19/34 (55.9%) (P < 0.0001). Non-response at 3 months was an independent predictor of subsequent colectomy (HR = 9.40, 95% CI = 5.10-17.35, P < 0.001). Concomitant azathioprine therapy did not influence outcome in terms of colectomy.Conclusions: Long-term efficacy of infliximab treatment in chronic active ulcerative colitis is excellent especially in patients who respond to induction treatment. Conversely, non-response at 3 months predicts a poor outcome, with a high risk of subsequent colectomy.
|
|
| 5. |
|
|
| 6. |
|
|
| 7. |
|
|
| 8. |
- Grännö, O., et al.
(author)
-
Preclinical protein signatures in blood predict Crohn's disease and Ulcerative colitis several years before the diagnosis
- 2024
-
In: Journal of Crohn's & Colitis. - : Oxford University Press. - 1873-9946 .- 1876-4479. ; 18:Suppl. 1, s. I660-I661
-
Journal article (other academic/artistic)abstract
- Background: We aimed to identify protein signatures predictive of a future diagnosis of inflammatory bowel disease (IBD).Methods: We conducted a case-control study, nested within large population-based cohorts with biorepositories. Samples were obtained from individuals who later in life were diagnosed with IBD (preclinical cases) and compared with age and sex-matched individuals who remained free from IBD during follow-up (controls). Using proximity extension assays (Olink, Uppsala), we measured 176 proteins. We applied regularized logistic regression to identify protein signatures of preclinical disease in serum from the discovery cohort (n=312). Their performance was validated in an external preclinical cohort (n=222). The biological relevance of identified proteins was further assessed in an inception cohort (n=144). Finally, we used an IBD twin cohort (n=327) to examine the impact of genetic and shared environmental factors on identified proteins.Results: We identified 34 proteins associated with preclinical Crohn’s disease (CD) in the discovery cohort (Pfalse discovery rate <0.10), with 9 confirmed in the validation cohort (Pfalse discovery rate <0.05). For preclinical ulcerative colitis (UC), 45 proteins were identified and 12 validated (Fig. 1A-B). In the discovery cohort, a signature of 29 proteins differentiated preclinical CD cases from controls with an AUC of 0.85 (Fig. 1G). Its performance was confirmed when applied to the preclinical validation cohort (AUC=0.84, Fig. 1H). Moreover, the signature had excellent capacity to differentiate newly diagnosed CD from healthy controls in the inception cohort (AUC = 0.99, Fig. 1I). The preclinical UC signature had a significant, but albeit lower, predictive capacity in the discovery (AUC=0.77), validation (AUC=0.67) and inception cohort (AUC=0.90, Fig. 1G-I).15 of 17 proteins associated with preclinical IBD demonstrated significantly higher intra-pair correlation coefficients in healthy monozygotic- compared to dizygotic twin pairs, indicating an influence from genetic factors on the regulation of these protein markers. The preclinical signature for CD demonstrated an AUC of 0.87 when comparing twins with preclinical CD (n=10) to matched external healthy twins. However, its predictive capacity was lower when comparing preclinical CD twins with their healthy twin siblings (AUC=0.58), i.e., when accounting for genetic and shared environmental factors. The difference in AUC estimates in the twin cohort was not significant (P=0.07).
|
|
| 9. |
- Karling, P., et al.
(author)
-
Prediagnostic markers in late onset inflammatory bowel disease
- 2019
-
In: Journal of Crohn's & Colitis. - : OXFORD UNIV PRESS. - 1873-9946 .- 1876-4479. ; 13, s. S186-S187
-
Journal article (other academic/artistic)abstract
- BackgroundWe aimed to determine whether patients who later develop IBD show signs of inflammatory activity in blood measured with high-sensitivity CRP, calprotectin and albumin before clinical onset of inflammatory bowel disease (IBD).MethodsWe identified 96 subjects who participated in the heath survey ‘Northern Sweden Health and Disease Study’ and who later developed IBD (70 UC and 26 CD). High-sensitivity CRP, calprotectin and albumin was analysed in stored blood donated from cases and sex-age-matched controls 1 to 15 years before diagnosis.ResultsWe found that subjects who later developed UC had lower albumin levels and subject who later developed CD had higher levels of CRP compared with the controls. Multi-variate conditional logistic regression with albumin, calprotectin and CRP showed a lower risk for developing IBD and UC with higher albumin levels (OR 0.789; CI 0.691–0.901 respective OR 0.773; CI 0.657–0.909). Higher CRP levels were associated with increased risk of developing CD (OR 1.314; CI 1.060–1.630). Adding BMI or smoking in the logistic regression model similar results was found. Serum calprotectin levels in the prediagnostic period in patients with IBD did not differ from controls.ConclusionsThis nested case–control study show that subjects who later develop IBD have signs of low-grade systemic inflammation years before the diseases become clinical. CRP and albumin was more sensitive to detect low-grade systemic inflammation than calprotectin.
|
|
| 10. |
- Karling, Pontus, et al.
(author)
-
Spectral analysis of heart rate variability in patients with irritable bowel syndrome.
- 1998
-
In: Scandinavian Journal of Gastroenterology. - : Informa UK Limited. - 0036-5521 .- 1502-7708. ; 33:6, s. 572-576
-
Journal article (peer-reviewed)abstract
- BACKGROUND: Autonomic dysfunction, both adrenergic and cholinergic, has been associated with the irritable bowel syndrome (IBS). The accuracy of the methods in use, however, has been limited by the need for active co-operation by the patients, with consequent difficulties in standardization. The aim of this study was to investigate the function of the autonomic nervous system in patients with IBS by using spectral analysis of the heart rate variability, an accurate method depending very little on patient cooperation. METHODS: Eighteen patients with IBS were compared with 36 sex- and age-matched controls. Spectral analysis of heart rate variability was performed to quantify sympathetic and parasympathetic nerve activity. RESULTS: The patients with IBS had significantly higher sympathetic activity than controls (P = 0.005). There was no significant (P = 0.308) increase in parasympathetic activity. There were no significant differences in heart rate or blood pressure between the patients and controls. CONCLUSION: Spectral analysis of heart rate variability has been used to assess the function of the autonomic nervous system in patients with IBS. IBS patients have significantly increased symphathetic activity, whereas parasympathetic activity does not differ from that of controls.
|
|
| 11. |
|
|
| 12. |
- Kochar, Bharati, et al.
(author)
-
Prevalence and Implications of Frailty in Older Adults With Incident Inflammatory Bowel Diseases : A Nationwide Cohort Study
- 2022
-
In: Clinical Gastroenterology and Hepatology. - : Elsevier. - 1542-3565 .- 1542-7714. ; 20:10, s. 2358-2365
-
Journal article (peer-reviewed)abstract
- Background and Aims: We aimed to compare the risk of frailty in older adults with incident inflammatory bowel disease (IBD) and matched non-IBD comparators and assess the association between frailty and future hospitalizations and mortality.Methods: In a cohort of patients with incident IBD ≥60 years of age from 2007 to 2016 in Sweden identified using nationwide registers, we defined frailty using Hospital Frailty Risk Score. We compared prevalence of frailty in patients with IBD with age, sex, place of residency– and calendar year–matched population comparators. In the IBD cohort, we used Cox proportional hazards modeling to examine the associations between frailty risk and hospitalizations or mortality.Results: We identified 10,590 patients with IBD, 52% female with a mean age of 71 years of age, matched to 103,398 population-based comparators. Among patients with IBD, 39% had no risk for frailty, 49% had low risk for frailty, and 12% had higher risk for frailty. Mean Hospital Frailty Risk Score was 1.9 in IBD and 0.9 in matched comparators (P < .01). Older adults with IBD at higher risk for frailty had a 20% greater risk for mortality at 3 years compared with those who were not frail. Compared with nonfrail older patients with IBD, patients at higher risk for frailty had increased mortality (hazard ratio [HR], 3.22, 95% confidence interval [CI], 2.86–3.61), all-cause hospitalization (HR, 2.42; 95% CI, 2.24–2.61), and IBD-related hospitalization (HR, 1.50; 95% CI, 1.35–1.66). These associations were not attenuated after adjusting for comorbidities.Conclusions: Frailty is more prevalent in older adults with IBD than in matched comparators. Among older patients with IBD, frailty is associated with increased risk for hospitalizations and mortality.
|
|
| 13. |
- Olén, Ola, et al.
(author)
-
Increasing Risk of Lymphoma Over Time in Crohn's Disease but Not in Ulcerative Colitis : A Scandinavian Cohort Study
- 2023
-
In: Clinical Gastroenterology and Hepatology. - : Elsevier. - 1542-3565 .- 1542-7714. ; 21:12, s. 3132-3142
-
Journal article (peer-reviewed)abstract
- Background & Aims: Earlier studies have provided varying risk estimates for lymphoma in patients with inflammatory bowel disease (IBD), but often have been limited by detection biases (especially during the first year of follow-up evaluation), misclassification, and small sample size; and rarely reflect modern-day management of IBD.Methods: We performed a binational register-based cohort study (Sweden and Denmark) from 1969 to 2019. We compared 164,716 patients with IBD with 1,639,027 matched general population reference individuals. Cox regression estimated hazard ratios (HRs) for incident lymphoma by lymphoma subtype, excluding the first year of follow-up evaluation.Results: From 1969 to 2019, 258 patients with Crohn's disease (CD), 479 patients with ulcerative colitis (UC), and 6675 matched reference individuals developed lymphoma. This corresponded to incidence rates of 35 (CD) and 34 (UC) per 100,000 person-years in IBD patients, compared with 28 and 33 per 100,000 person-years in their matched reference individuals. Although both CD (HR, 1.32; 95% CI, 1.16–1.50) and UC (HR, 1.09; 95% CI, 1.00–1.20) were associated with an increase in lymphoma, the 10-year cumulative incidence difference was low even in CD patients (0.08%; 95% CI, 0.02–0.13). HRs have increased in the past 2 decades, corresponding to increasing use of immunomodulators and biologics during the same time period. HRs were increased for aggressive B-cell non-Hodgkin lymphoma in CD and UC patients, and for T-cell non-Hodgkin lymphoma in CD patients. Although the highest HRs were observed in patients exposed to combination therapy (immunomodulators and biologics) or second-line biologics, we also found increased HRs in patients naïve to such drugs.Conclusions: During the past 20 years, the risk of lymphomas have increased in CD, but not in UC, and were driven mainly by T-cell lymphomas and aggressive B-cell lymphomas.
|
|
| 14. |
|
|
| 15. |
- Shrestha, Sarita, 1991-, et al.
(author)
-
The use of ICD codes to identify IBD subtypes and phenotypes of the Montreal classification in the Swedish National Patient Register
- 2020
-
In: Scandinavian Journal of Gastroenterology. - : Informa UK Limited. - 0036-5521 .- 1502-7708. ; 55:4, s. 430-435
-
Journal article (peer-reviewed)abstract
- Introduction: Whether data on International Classification of Diseases (ICD)-codes from the Swedish National Patient Register (NPR) correctly correspond to subtypes of inflammatory bowel disease (IBD) and phenotypes of the Montreal classification scheme among patients with prevalent disease is unknown. Materials and methods: We obtained information on IBD subtypes and phenotypes from the medical records of 1403 patients with known IBD who underwent biological treatment at ten Swedish hospitals and retrieved information on their IBD-associated diagnostic codes from the NPR. We used previously described algorithms to define IBD subtypes and phenotypes. Finally, we compared these register-generated subtypes and phenotypes with the corresponding information from the medical records and calculated positive predictive values (PPV) with 95% confidence intervals. Results: Among patients with clinically confirmed disease and diagnostic listings of IBD in the NPR (N = 1401), the PPV was 97 (96-99)% for Crohn's disease, 98 (97-100)% for ulcerative colitis, and 8 (4-11)% for IBD-unclassified. The overall accuracy for age at diagnosis was 95% (when defined as A1, A2, or A3). Examining the validity of codes representing disease phenotype, the PPV was 36 (32-40)% for colonic Crohn's disease (L2), 61 (56-65)% for non-stricturing/non-penetrating Crohn's disease behaviour (B1) and 83 (78-87)% for perianal disease. Correspondingly, the PPV was 80 (71-89)% for proctitis (E1)/left-sided colitis (E2) in ulcerative colitis. Conclusions: Among people with known IBD, the NPR is a reliable source of data to classify most subtypes of prevalent IBD, even though misclassification commonly occurred in Crohn's disease location and behaviour and also among IBD-unclassified patients.
|
|
| 16. |
- Visuri, Isabella, 1991-, et al.
(author)
-
Anti-TNF agent drug survival in patients with IBD : real-world comparisons of individual anti-TNF agents based on the Swedish National Quality Registry for IBD (SWIBREG)
- 2019
-
In: Journal of Crohn's & Colitis. - : OXFORD UNIV PRESS. - 1873-9946 .- 1876-4479. ; 13, s. S443-S444
-
Journal article (other academic/artistic)abstract
- Background: Studies comparing drug survival in different anti-tumour necrosis factor (TNF) agents in IBD patients are scarce, especially for second-line anti-TNF agents. We aimed to (A) assess drug survival and predictors of response and adverse drug reactions to first-line anti-TNF treatment and (B) examine drug survival for individual anti-TNF agents when used as second-line anti-TNF. Methods: Well-characterised patients with IBD (n = 955) starting their first anti-TNF treatment between 2006 and 2016 (Table 1), were identified from the Swedish National Quality Registry for IBD (SWIBREG). Drug survival was examined, stratified by reason for discontinuation, that is, lack/loss of clinical effectiveness or adverse drug reactions. Multi-variable Cox regression models were used to identify predictors of drug survival. Drug survival for the second anti-TNF was assessed by type of first anti-TNF agent. Results: Risk factors at baseline for shorter drug survival, in patients with Crohn’s disease, were use of infliximab as first-line anti-TNF (compared with adalimumab, adjusted HR = 1.95, 95% CI: 1.19‒3.18) (Figure 1A) and colonic disease (L2) (compared with ileal disease (L1) and ileocolonic disease (L3), adjusted HR = 2.16, 95% CI: 1.25‒3.74). Consistently, Crohn’s disease patients who switched from adalimumab to infliximab had shorter drug survival, compared with those who switched from infliximab to adalimumab (Figure 1B). A normalisation of CRP level at 3 months was associated with decreased risk of short drug survival in both Crohn’s disease (adjusted HR = 0.40, 95% CI: 0.19‒0.81) and ulcerative colitis (adjusted HR = 0.40, 95% CI: 0.19‒0.86). In Crohn’s disease, but not in ulcerative colitis, immunomodulators were associated with a lower risk of short drug survival due to adverse drug reactions (adjusted HR = 0.50, 95% CI: 0.31‒0.82). Conclusions: Drug survival duration was longer for adalimumab compared with infliximab both when used as first anti-TNF agent and when used as second-line treatment. The consistent pattern indicates that these differences are not only explained by channelling bias (differential prescribing behaviour).
|
|
