Table 2

Selected studies for systematic review and meta-analysis

AuthorPublication yearType of studyType of manuscriptOriginCentresTime framePatients with perianal fistulaDefinition of responseDefinition of remissionFirst time framePatients with responsePatients in remissionSecond time framePatients with improvementPatients in remissionThird time framePatients with improvementPatients in remission
Harris et al112020Retrospective observationalFull manuscriptUK1Unspecified8Improvement in PGA categoryUnspecifiedMedian 14.7 weeks (IQR 5–21)3/8N/AN/AN/AN/AN/AN/AN/A
Weaver et al202019Retrospective observationalFull manuscriptUSA42013–201819Decrease in fistula drainageUnspecified6 months9/11N/AN/AN/AN/AN/AN/AN/A
Chavannes et al212019Retrospective observationalFull manuscriptCanada, USA, France, Australia42014–20182Changes in mean aPCDAI)aPCDAI <106 months0/20/212 months0/10/1N/AN/AN/A
Krugliack et al222018Retrospective cohortAbstractUSA12013–201716Clinical assessment: cessation of drainage and no abscessUnspecified6 months10/16N/AN/AN/AN/AN/AN/AN/A
Satyam et al132018Retrospective observationalAbstractUSA12013–201721Improvement in perianal symptoms as assessed by a treating physician and continuation of ustekinumabComplete absence of perianal symptoms on history, physical exam and endoscopy if availableMean 382 days (64–1271)7/212/21N/AN/AN/AN/AN/AN/A
Battat et al232017Case seriesAbstractCanada12013–20156>50% reduction from baseline in the number of draining fistulasClosure of all fistulas>6 months4/62/6N/AN/AN/AN/AN/AN/A
Tsistrakis and Oikonomou242017Retrospective observationalAbstractUSA12016–20176Decrease in fistulous drainage or partial healing of fistulasComplete closure of fistula3 months2/51/5N/AN/AN/AN/AN/AN/A
Ma et al252017Retrospective cohortFull manuscriptCanada22011–201645Reduction in number of draining fistulas by 50% compared with baseline as assessed by physical exam without the need for surgical interventions including exam under anesthesia, fistulotomy or seton placementComplete absence of fistula drainage on patient history and closure of all fistulas on physical exam12 months22/4512/45N/AN/AN/AN/AN/AN/A
Sands152017Randomized prospective clinical trialAbstractUSA, Canada, Belgium, South Africa, UK2602011–2015161>50% reduction in draining fistulas100% fistula reduction8 weeks39/15037/15022 weeks9/19N/A44 weeks12/15NA
Khorrami et al122016Retrospective observationalFull manuscriptSpain422010–201418Physician judgementUnspecifiedMedian 10 months (IQR 5–21)11/18N/AN/AN/AN/AN/AN/AN/A
Bishop et al102016Paediatric case seriesFull manuscriptUSA12013–20142UnspecifiedUnspecifiedMean 11 months±4.9½N/AN/AN/AN/AN/AN/AN/A
Wils et al142018Retrospective observationalFull manuscriptFrance, Switzerland202011–201412Significant improvement in CD-related clinical symptoms and laboratory tests assessed by the patient’s physician leading to continued ustekinumab treatment, associated with complete weaning from steroids if they were being taken at inclusion, without surgery or immunosuppressant introductionUnspecifiedMedian 12 weeks (39.2±32.8)8/12N/AN/AN/AN/AN/AN/AN/A
Kopylov et al262014Retrospective observationalFull manuscriptCanada12011–201313Improvement in the patient’s symptoms coupled with the decision to continue ustekinumab treatment Physician’s assessmentUnspecified12 weeks9/13N/A12 months¾N/AN/AN/AN/A
Attauabi et al272020Retrospective cohortFull manuscriptDenmark22015–202018Fistula response was defined as a combination of the physician’s objective assessment and the patient’s self-reported improvement in disease symptoms without the need for surgical procedures compared with baseline.Fistula remission was defined as healing with no secretion or symptomatic activity.8 weeks3/180/1824 weeks6/120/1252 weeks7/11N/A
Straatmijer et al282021Prospective cohortFull manuscriptThe Netherlands8Unspecified29Clinical response (at least
three points HBI reduction)		Corticosteroid-free clinical remission
(HBI ≤4)		12 weeks5/29N/A24 weeks11/29N/A52 weeks11/29N/A
Plevris et al292020Retrospective cohortFull manuscriptIsrael142017–201937Perianal response was determined by follow-up MRI (reduction in enhancement, closure or fibrosis of tract compared with baseline MRI)Unspecified24 weeks3/24N/A52 weeks4/7N/ANAN/AN/A
Bar-Gil Shitrit et al302020Prospective cohortFull manuscriptIsrael8Unspecified26Patients were described as having or stopped having perianal fistulas, which were described as actively draining perianal fistula.Unspecified8 weeks6/26N/A24 weeks8/26N/AN/AN/AN/A
Tursi et al312021Retrospective cohortFull manuscriptItaly25Up to 201927HBS <5 after 3 months of follow-upUnspecified8 weeks16/2716/27Mean of 12 months14/2714/27N/AN/AN/A
Miyazaki et al322019Retrospective cohortFull manuscriptJapan12017–20189Decrease in CDAI of >100 points from the baselineCDA<150 points8 weeks2/9N/AN/AN/AN/AN/AN/AN/A
Bacaksız et al332021Retrospective cohortFull manuscriptTurkey120185Clinical response was defined as a decrease of 70
points in CDAI score; a decrease of 3 points in the HBI was accepted as clinical response.		Clinical remission was defined as a CDAI score of <150; an HBI score of 4 was accepted as clinical remission.8 weeks4/52/552 weeks2/22/2N/AN/AN/A
Marquès-Camí et al342020Retrospective cohortFull manuscriptSpain12009–20198The
CDAI23 was used to evaluate disease activity, and the long-term clinical remission was defined by a cut-off of less than 150 points during the
52 weeks of treatment.		The
CDAI23 was used to evaluate disease activity, and the long-term clinical remission was defined by a cut-off of less than 150 points during the
52 weeks of treatment.		52 weeks5/85/8N/AN/AN/AN/AN/AN/A
Manlay et al352021Retrospective cohortFull manuscriptFrance22014–202039UnspecifiedDeep remission
(=combination of corticosteroid-free clinical remission and deep biological remission), active perianal lesions (defined as the persistence of draining, perianal pain or abscesses		14 weeksN/A17/3624 weeksN/A15/3054 weeksN/A14/21
Yokoyama et al322021Retrospective cohortFull manuscriptJapan912017–202065Clinical response (defined as reduction from baseline in the CDAI score of ≥100
points)		Clinical remission (defined as a CDAI score of
≤150) at week 8		8 weeks12/6512/65N/AN/AN/AN/AN/AN/A
Chapuis-Biron et al92020ProspectiveFull manuscriptFrance182020148Clinical success at 6 months of treatment assessed by the physicians’ judgement,with (1) no need for dedicated medical treatment for perianal lesions (antibiotics and/or topics) nor (2) unscheduled surgical treatment such as abscess drainage, fistulectomy, fistulotomy, seton drainage, stricture dilatation or abdominoperineal resectionUnspecifiedMedian 52.1 (19.6–69.4)57/148N/AN/AN/AN/AN/AN/AN/A
Takeuchi et al362020Retrospective cohortFull manuscriptJapan1By 20196Weighted paediatric CD Activity Index (wPCDAI) was used to assess their disease activity. Clinical remission was defined as wPCDAI under 10, and steroid-free clinical remission was defined as clinical remission without corticosteroids. For patients who underwent ileocolonoscopy during their follow-up, the change in disease activity was assessed by using the simple endoscopic score for CD.Clinical remission was defined as wPCDAI under 10, and steroid-free clinical remission was defined as clinical remission without corticosteroids.26 weeks2/60/6N/AN/AN/AN/AN/AN/A

  • aPCDAI, Abberviated Paediatric Crohn’s Disease Activity Index; CD, Crohn’s disease; CDAI, Crohn’s Disease Activity Index; HBI, Harvey-Bradshaw Index; N/A, not available; PCDAI, Paediatric Crohn’s Disease Activity Index; PGA, physician global assessment; wPCDAI, Weighted Paediatric Crohn’s Disease Activity Index.