Endoscopic assessment of the J pouch in ulcerative colitis: A narrative review.

Patients with ulcerative colitis sometimes need a total colectomy with ileal pouch-anal anastomosis due to medically refractory disease or colitis-associated neoplasia. Up to 50% of patients with ulcerative colitis postoperatively develop pouchitis and the rate of chronic inflammatory pouch conditions requiring pouch excision or diverting ileostomy is reported to be 10%. In order to diagnose and monitor pouchitis, pouchoscopy is essential to assess endoscopic inflammatory findings of the J pouch and to survey neoplasia development, particularly in the remnant distal rectum. However, endoscopic protocols for the evaluation of the pouch may not be standardized worldwide and the reliability of existing disease activity indices for pouchitis has been questioned due to the lack of validation. Recently, reliable endoscopic scoring systems based on an observation of the anatomical location of the J pouch were reported and a significant association between the distribution pattern of endoscopic inflammation (i.e., endoscopic phenotype) and pouch outcomes was also uncovered. In this review, we discuss how to survey the J pouch using pouchoscopy, endoscopic indices for pouchitis disease activity, endoscopic phenotypes and classification, and the pathological mechanisms of pouchitis phenotype in patients with ulcerative colitis.

The prevalence of pouch fistulas in ulcerative colitis following restorative proctocolectomy: a systematic review and meta-analysis.

Background/Aims: One complication of restorative proctocolectomy with ileo-anal pouch anastomosis is fistula formation in the pouch. Fistulas can be associated with significant morbidity and pouch failure. We conducted a systematic review with meta- analysis to try and understand the prevalence of pouch fistulas in patients with ulcerative colitis following restorative proctocolectomy. Methods: The Embase, Embase Classic, and PubMed databases were searched between January 1979 and April 2022. Studies were included if there were cross-sectional, case-controlled, population-based or cohort studies reporting on prevalence of pouch fistulas in ulcerative colitis. Studies had to report the number of patients with pouch fistulas using either clinical, endoscopic, or radiological diagnosis in an adult population. Results: Thirty-three studies screened met the inclusion criteria. The pooled prevalence of developing at least 1 fistula was 0.05 (95% confidence interval [CI], 0.04-0.07). The pooled prevalence of pouch failure in patients with pouch fistula was found to be 0.24 (95% CI, 0.19-0.30). The pooled prevalence of developing a pouch fistula at 3 years, 5 years and more than 5 years was 0.04 (95% CI, 0.02-0.07), 0.05 (95% CI, 0.02-0.07), and 0.05 (95% CI, 0.02-0.10), respectively. Conclusions: This is the first systematic review and meta-analysis to report the prevalence of pouch fistula. It also provides a pooled prevalence of pouch failure in these patients. These results can help to shape future guidelines, power future studies, and help counsel patients.

Assessing the Value of Histology and Anatomic Segment Evaluation Among Patients Undergoing Pouchoscopy.

BACKGROUND: The value of histologic assessment after ileal pouch-anal anastomosis (IPAA) has not been definitively determined. We evaluated the correlation between histology and endoscopic findings, as well as the proportion of patients with inflammation in areas beyond the pouch body on their initial pouchoscopy after IPAA. METHODS: In a retrospective cohort study, we evaluated patients who underwent IPAA for UC between 2012 and 2020 and subsequently underwent a pouchoscopy with routine biopsies of the pouch body, pre-pouch ileum, and rectal cuff. We compared endoscopic and histologic assessments in each location using χ2 testing and Spearman correlation, as well as the development of pouchitis and Crohn's-like disease of the pouch (CLDP) in longitudinal follow-up. RESULTS: Among 126 patients, the median time to pouchoscopy after IPAA was 384 days, with 82 patients (65%) having inflammation of the pouch body. Significantly more patients with pouch body inflammation had histologic inflammation compared with patients without pouch body inflammation (96% vs 22%, P < .001, r = 0.769). Additionally, 16 patients (13%) were found to have endoscopic inflammation of the pre-pouch ileum with corresponding histologic inflammation in 88%; of these, 31% later developed CLDP. In contrast, 13% of patients with no endoscopic inflammation displayed histologic inflammation, with none later developing CLDP. Forty-six percent of patients had rectal cuff inflammation (correlation with histologic inflammation r = 0.580). CONCLUSIONS: In our evaluation, the added benefit of histology in the presence of visible endoscopic inflammation for disease activity assessment scores is unclear. The prognostic value of histologic inflammation without endoscopic inflammation warrants a longitudinal study.

Endoscopic evaluation after ileal pouch-anal anastomosis should include anatomic areas beyond the pouch body, including the rectal cuff and the pre-pouch ileum. The added benefit of histology in the presence of visible inflammation when assessing disease activity is unclear.

Risankizumab Is Effective for The Management of Crohn's Disease of the Pouch.

In this prospective, multicenter observational study of highly refractory patients with Crohn's disease of the pouch, risankizumab achieved the primary outcome of clinical remission in 50% and the more stringent secondary outcome of antibiotic- and steroid-free remission in 30.8% at 12 weeks.

Acute Kidney Injury in Inflammatory Bowel Disease Patients: A Nationwide Comparative Analysis.

Rationale & Objective: About 25%-40% of patients with inflammatory bowel disease (IBD) may have extraintestinal manifestations, mainly involving the liver, skin, and joints. Kidney involvement in patients with IBD has been reported, but there are no estimates of its prevalence in population-based studies in the United States. We compared the frequency of acute kidney injury (AKI) among hospitalizations with IBD with that among hospitalizations with collagen vascular diseases and hospitalizations with neither condition. Study Design: Retrospective, population-based cohort study. Setting & Participants: Healthcare Cost and Utilization Project-Nationwide Inpatient Sample database. Outcomes: AKI and AKI requiring dialysis. Analytical Approach: Regression models were used to compare the occurrence of AKI among groups. Inverse probability of treatment weighting was applied to balance groups on covariates. Results: The final sample comprised 5,735,804 hospitalizations, including 57,121 with IBD, 159,930 with collagen vascular diseases, and 5,518,753 with neither IBD nor collagen vascular diseases. AKI was observed in 13%, 15%, and 12.2% of hospitalizations with IBD, collagen vascular diseases, and the general population, respectively. When adjusting for demographic, hospital, and clinical characteristics using inverse probability of treatment weighting, hospitalizations with IBD had higher odds of being diagnosed with AKI than both those with collagen vascular diseases (odds ratio [OR], 1.32; 95% confidence interval [CI], 1.27-1.38) and the general population (OR, 1.27; 95% CI, 1.23-1.31) and also had higher odds of being diagnosed with AKI requiring dialysis than those with collagen vascular diseases (OR, 1.59; 95% CI, 1.31-1.94) or than the general population (OR, 1.45; 95% CI, 1.25-1.68). Limitations: Cross-sectional analysis, underreporting of International Classification of Diseases codes, and analyses relevant to in-hospital stays only. Conclusions: The prevalence and risk of AKI among hospitalizations with IBD is greater than that of hospitalizations with collagen vascular diseases and the general population. Coexisting kidney disease should be considered among patients with a known diagnosis of IBD.

As a nephrologist, we have evaluated many patients with inflammatory bowel disease with various forms of kidney disease, both inflammatory and noninflammatory. Based on a multitude of factors, we have always wondered if there are shared immune mechanisms between the gut and kidney that could explain the underlying inflammation in both organs. In addition, based on recent studies of other autoimmune/inflammatory diseases, there is growing interest in the role of the gut microbiome (microorganisms that reside in our gut) and its influence on the immune system as well as how both the altered microbiome and immune system affect the kidneys. As a first step, we wanted to understand if some forms of kidney disease are more prevalent in patients with inflammatory bowel disease than in the general population, which possibly suggests a shared pathogenesis.

Histologic Activity From Neoterminal Ileal Biopsies in Patients With Crohn's Disease in Endoscopic Remission is Associated With Postoperative Recurrence.

INTRODUCTION: Following ileocolic resection (ICR), the clinical importance and prognostic implications of histologic activity on biopsies in Crohn's disease (CD) patients with endoscopic remission are not well defined. The aim of this study was to determine if histologic activity in patients with endoscopic remission is associated with future risk of endoscopic and/or radiologic postoperative recurrence (POR). METHODS: In this multicenter retrospective cohort study, adult patients with CD who underwent ICR between 2009 and 2020 with endoscopic biopsies of ileal mucosa from Rutgeerts i0 on index colonoscopy were included. The composite rate of endoscopic (Rutgeerts score ≥i2b) and radiologic (active inflammation on imaging) recurrence was compared in patients with and without histologic activity using a Kaplan-Meier survival analysis. A multivariable Cox proportional hazard regression model including clinically relevant risk factors of POR, postoperative biologic prophylaxis, and histology activity was designed. RESULTS: A total of 113 patients with i0 disease on index colonoscopy after ICR were included. Of these, 42% had histologic activity. Time to POR was significantly earlier in the histologically active versus normal group ( P = 0.04). After adjusting for clinical risk factors of POR, histologic activity (HR 2.37, 95% CI 1.17-4.79; P = 0.02) and active smoking (HR 2.54, 95% CI 1.02-6.33; P = 0.05) were independently associated with subsequent composite POR risk. DISCUSSION: In patients with postoperative CD, histologic activity despite complete endoscopic remission is associated with composite, endoscopic, and radiographic recurrence. Further understanding of the role of histologic activity in patients with Rutgeerts i0 disease may provide a novel target to reduce disease recurrence in this population.

Diagnosis of Inflammatory Bowel Disease-Associated Peripheral Arthritis: A Systematic Review.

BACKGROUND: Inflammatory bowel disease (IBD)-associated peripheral spondyloarthritis (pSpA) decreases quality of life and remains poorly understood. Given the prevalence of this condition and its negative impact, it is surprising that evidence-based disease definitions and diagnostic strategies are lacking. This systematic review summarizes available data to facilitate development and validation of diagnostics, patient-reported outcomes, and imaging indices specific to this condition. METHODS: A literature search was conducted. Consensus or classification criteria, case series, cross-sectional studies, cohort studies, and randomized controlled trials related to diagnosis were included. RESULTS: A total of 44 studies reporting data on approximately 1500 patients with pSpA were eligible for analysis. Data quality across studies was only graded as fair to good. Due to large heterogeneity, meta-analysis was not possible. The majority of studies incorporated patient-reported outcomes and a physical examination. A total of 13 studies proposed or validated screening tools, consensus, classification, or consensus criteria. A total of 28 studies assessed the role of laboratory tests, none of which were considered sufficiently accurate for use in diagnosis. A total of 17 studies assessed the role of imaging, with the available literature insufficient to fully endorse any imaging modality as a robust diagnostic tool. CONCLUSIONS: This review highlights existing inconsistency and lack of a clear diagnostic approach for IBD-associated pSpA. Given the absence of an evidence-based approach, a combination of existing criteria and physician assessment should be utilized. To address this issue comprehensively, our future efforts will be directed toward pursuit of a multidisciplinary approach aimed at standardizing evaluation and diagnosis of IBD-associated pSpA.

This systematic review highlights the lack of an evidence-based approach to the diagnosis of inflammatory bowel disease­associated peripheral spondyloarthritis and the need to standardize evaluation and diagnosis via multidisciplinary collaboration with development of patient-reported outcomes and imaging indices.

The Natural History After Ileal Pouch-Anal Anastomosis for Ulcerative Colitis: A Population-Based Cohort Study From the United States.

INTRODUCTION: There are limited data regarding the natural history after ileal pouch-anal anastomosis (IPAA) for ulcerative colitis (UC). The principal objectives of this study were to identify 4 key outcomes in the natural history after IPAA within 1, 3, 5, and 10 years: the incidence of pouchitis, Crohn's-like disease of the pouch, use of advanced therapies after IPAA, and pouch failure requiring excision in a network of electronic health records. METHODS: We performed a retrospective cohort study in TriNetX, a research network of electronic health records. In addition to evaluating incidence rates, we also sought to identify factors associated with pouchitis and advanced therapy use within 5 years of IPAA after 1:1 propensity score matching, expressed as adjusted hazard ratios (aHRs). RESULTS: Among 1,331 patients who underwent colectomy with IPAA for UC, the incidence of pouchitis increased from 58% in the first year after IPAA to 72% at 10 years after IPAA. After propensity score matching, nicotine dependence (aHR 1.61, 95% confidence interval [CI] 1.19-2.18), antitumor necrosis factor therapy (aHR 1.33, 95% CI 1.13-1.56), and vedolizumab prior to colectomy (aHR 1.44, 95% CI 1.06-1.96) were associated with an increased risk of pouchitis in the first 5 years after IPAA. The incidence of Crohn's-like disease of the pouch increased to 10.3% within 10 years of IPAA while pouch failure increased to 4.1%. The incidence of advanced therapy use peaked at 14.4% at 10 years after IPAA. DISCUSSION: The incidence of inflammatory conditions of the pouch remains high in the current era, with 14% of patients requiring advanced therapies after IPAA.

Clinical Decision Making in Inflammatory Bowel Disease Mimics: Practice Management from Inflammatory Bowel Disease LIVE.

Background: Since 2009, inflammatory bowel disease (IBD) specialists have utilized "IBD LIVE," a weekly live video conference with a global audience, to discuss the multidisciplinary management of their most challenging cases. While most cases presented were confirmed IBD, a substantial number were diseases that mimic IBD. We have categorized all IBD LIVE cases and identified "IBD-mimics" with consequent clinical management implications. Methods: Cases have been recorded/archived since May 2018; we reviewed all 371 cases from May 2018-February 2023. IBD-mimics were analyzed/categorized according to their diagnostic and therapeutic workup. Results: Confirmed IBD cases made up 82.5% (306/371; 193 Crohn's disease, 107 ulcerative colitis, and 6 IBD-unclassified). Sixty-five (17.5%) cases were found to be mimics, most commonly medication-induced (n = 8) or vasculitis (n = 7). The evaluations that ultimately resulted in correct diagnosis included additional endoscopic biopsies (n = 13, 21%), surgical exploration/pathology (n = 10, 16.5%), biopsies from outside the GI tract (n = 10, 16.5%), genetic/laboratory testing (n = 8, 13%), extensive review of patient history (n = 8, 13%), imaging (n = 5, 8%), balloon enteroscopy (n = 5, 8%), and capsule endoscopy (n = 2, 3%). Twenty-five patients (25/65, 38%) were treated with biologics for presumed IBD, 5 of whom subsequently experienced adverse events requiring discontinuation of the biologic. Many patients were prescribed steroids, azathioprine, mercaptopurine, or methotrexate, and 3 were trialed on tofacitinib. Conclusions: The diverse presentation of IBD and IBD-mimics necessitates periodic consideration of the differential diagnosis, and reassessment of treatment in presumed IBD patients without appropriate clinical response. The substantial differences and often conflicting treatment approaches to IBD versus IBD-mimics directly impact the quality and cost of patient care.

The Pouch Corner: A Review of Functional Pouch Disorders.

Functional pouch disorders such as dyssynergic defecation, fecal incontinence, and irritable pouch syndrome are common and manifest with symptoms that overlap with those of pouchitis. The appropriate recognition of these disorders is imperative to guide necessary management and reduce unnecessary antibiotic exposure.

Efficacy and Safety of Liraglutide in Patients With an Ileal Pouch-Anal Anastomosis and Chronic High Bowel Frequency: A Placebo-Controlled, Crossover, Proof-of-Concept Study.

INTRODUCTION: After colectomy with ileoanal pouch anastomosis (IPAA), many patients develop high bowel frequency (BF) refractory to antimotility agents, despite normal IPAA morphology. Low circulating levels of glucagon-like protein-1 (GLP-1), a modulator of gastroduodenal motility, have been reported after colectomy. METHODS: Double-blind crossover study of 8 IPAA patients with refractory high BF treated with daily administration of the GLP-1 receptor agonist liraglutide or placebo. RESULTS: Liraglutide, but not placebo, reduced daily BF by more than 35% ( P < 0.03). DISCUSSION: Larger randomized controlled studies are warranted to delineate the treatment potential of GLP-1 receptor agonists in IPAA patients suffering from noninflammatory high BF.

Antibiotic Use in the 12 Months Prior to Ileal Pouch-Anal Anastomosis Increases the Risk for Pouchitis.

BACKGROUND & AIMS: Pouchitis is the most common complication after ileal pouch-anal anastomosis (IPAA) for ulcerative colitis (UC); however, clinical and environmental risk factors for pouchitis remain poorly understood. We explored the relationship between specific clinical factors and the incidence of pouchitis. METHODS: We established a population-based cohort of all adult persons in Denmark undergoing proctocolectomy with IPAA for UC from 1996-2020. We used Cox proportional hazard modeling to assess the impact of antibiotic, nonsteroidal anti-inflammatory drug (NSAID) exposure, and appendectomy on diagnosis of acute pouchitis in the first 2 years after IPAA surgery. RESULTS: Among 1616 eligible patients, 46% developed pouchitis in the first 2 years after IPAA. Antibiotic exposure in the 12 months before IPAA was associated with an increased risk of pouchitis (adjusted hazard ratio [aHR], 1.41; 95% confidence interval [CI], 1.22-1.64) after adjusting for anti-tumor necrosis factor alpha use and sex. Compared with persons without any antibiotic prescriptions in the 12 months before IPAA, the risk of pouchitis was increased in those with 1 or 2 courses of antibiotics in that period (aHR, 1.30; 95% CI, 1.11-1.52) and 3 or more courses (aHR, 1.77; 95% CI, 1.41-2.21). NSAID exposure in the 12 months before IPAA and appendectomy were not associated with risk of acute pouchitis (P = .201 and P = .865, respectively). CONCLUSIONS: In this population-based cohort study, we demonstrated that antibiotic exposure in the 12 months before IPAA is associated with an increased risk of acute pouchitis. Future prospective studies may isolate specific microbial changes in at-risk patients to drive earlier interventions.

One-Year Comparative Effectiveness of Upadacitinib vs Tofacitinib for Ulcerative Colitis: A Multicenter Cohort Study.

INTRODUCTION: The comparative effectiveness of upadacitinib and tofacitinib for ulcerative colitis (UC) is poorly understood. METHODS: In this retrospective cohort study, we compared steroid-free clinical remission (SFCR) and endoscopic response/remission at 52 weeks among adults initiating upadacitinib or tofacitinib for UC. RESULTS: A total of 155 patients initiated upadacitinib (n = 81; 30% prior tofacitinib exposure) or tofacitinib (n = 74; 0% prior upadacitinib exposure). After inverse probability of treatment-weighted logistic regression, upadacitinib was associated with significantly higher odds of SFCR (odds ratio 3.01, 95% confidence interval 1.39-6.55) vs tofacitinib. There were no differences for endoscopic response/remission. DISCUSSION: Upadacitinib was more effective at achieving SFCR in UC at 52 weeks vs tofacitinib.

Patients With Inflammatory Bowel Disease Are at Increased Risk of Hospitalization Due to Respiratory Syncytial Virus.

INTRODUCTION: Patients with inflammatory bowel disease (IBD) are at increased risk of developing respiratory infections. Respiratory syncytial virus (RSV) is a common respiratory virus with adverse outcomes in older adults. This study aimed to determine whether patients with IBD are at increased risk of a serious infection due to RSV. METHODS: We conducted a retrospective study using the multi-institutional research network TriNetX to assess the risk of hospitalization in a cohort of patients with IBD compared with that in a non-IBD control cohort with RSV infection from January 1, 2007, to February 27, 2023. One-to-one (1:1) propensity score matching was performed for demographic variables and RSV risk factors between the 2 cohorts. Risk was expressed as adjusted odds ratio (aOR) with 95% confidence interval (CI). RESULTS: There were 794 patients in the IBD-RSV cohort and 93,074 patients in the non-IBD-RSV cohort. The mean age of the IBD-RSV cohort was 55.6 ± 20 years, 59% were female, 80% were White, and 56.9% had Crohn's disease. The IBD-RSV cohort was at an increased risk of hospitalization (aOR 1.30, 95% CI 1.06-1.59). There was no difference in the risk (aOR 0.83, 95% CI 0.58-1.19) of a composite outcome of hospitalization-related complications between the 2 cohorts. Recent systemic corticosteroid use (<3 months) was associated with an increased risk of hospitalization (aOR 1.86, 95% CI 1.30-2.59) in the IBD-RSV cohort. DISCUSSION: We found that adult patients with IBD and RSV infection are at an increased risk of hospitalization and may benefit from the new RSV vaccine recommended for adults aged 60 years and older.

Factors Associated With Performing IPAA After Total Colectomy for Ulcerative Colitis.

BACKGROUND: IPAA is considered the procedure of choice for restorative surgery after total colectomy for ulcerative colitis. Previous studies have examined the rate of IPAA within individual states but not at the national level in the United States. OBJECTIVE: This study aimed to assess the rate of IPAA after total colectomy for ulcerative colitis in a national population and identify factors associated with IPAA. DESIGN: This was a retrospective cohort study. SETTINGS: This study was performed in the United States. PATIENTS: Patients who were aged 18 years or older and who underwent total colectomy between 2009 and 2019 for a diagnosis of ulcerative colitis were identified within a commercial database. This database excluded patients with public insurance, including all patients older than 65 years with Medicare. MAIN OUTCOME MEASURES: The primary outcome was IPAA. Multivariable logistic regression was used to assess the association between covariates and the likelihood of undergoing IPAA. RESULTS: In total, 2816 patients were included, of whom 1414 (50.2%) underwent IPAA, 928 (33.0%) underwent no further surgery, and 474 (16.8%) underwent proctectomy with end ileostomy. Younger age, lower comorbidities, elective case, and laparoscopic approach in the initial colectomy were significantly associated with IPAA but socioeconomic status was not. LIMITATIONS: This retrospective study included only patients with commercial insurance. CONCLUSIONS: A total of 50.2% of patients who had total colectomy for ulcerative colitis underwent IPAA, and younger age, lower comorbidities, and elective cases are associated with a higher rate of IPAA placement. This study emphasizes the importance of ensuring follow-up with colorectal surgeons to provide the option of restorative surgery, especially for patients undergoing urgent or emergent colectomies. See Video Abstract . FACTORES ASOCIADOS CON LA REALIZACIN DE ANASTOMOSIS ANALBOLSA ILEAL DESPUS DE UNA COLECTOMA TOTAL POR COLITIS ULCEROSA: ANTECEDENTES:La anastomosis ileo-anal se considera el procedimiento de elección para la cirugía reparadora tras la colectomía total por colitis ulcerosa. Estudios previos han examinado la tasa de anastomosis ileo-anal dentro de los estados individuales, pero no a nivel nacional en los Estados Unidos.OBJETIVO:Evaluar la tasa de anastomosis bolsa ileal-anal después de la colectomía total para la colitis ulcerosa en una población nacional e identificar los factores asociados con la anastomosis bolsa ileal-anal.DISEÑO:Se trata de un estudio de cohortes retrospectivo.LUGAR:Este estudio se realizó en los Estados Unidos.PACIENTES:Los pacientes que tenían ≥18 años de edad que se sometieron a colectomía total entre 2009 y 2019 para un diagnóstico de colitis ulcerosa fueron identificados dentro de una base de datos comercial. Esta base de datos excluyó a los pacientes con seguro público, incluidos todos los pacientes >65 años con Medicare.MEDIDAS DE RESULTADO PRINCIPALES:El resultado primario fue la anastomosis ileal bolsa-anal. Se utilizó una regresión logística multivariable para evaluar la asociación entre las covariables y la probabilidad de someterse a una anastomosis ileal.RESULTADOS:En total, se incluyeron 2.816 pacientes, de los cuales 1.414 (50,2%) se sometieron a anastomosis ileo-anal, 928 (33,0%) no se sometieron a ninguna otra intervención quirúrgica y 474 (16,8%) se sometieron a proctectomía con ileostomía terminal. La edad más joven, las comorbilidades más bajas, el caso electivo, y el abordaje laparoscópico en la colectomía inicial se asociaron significativamente con la anastomosis ileal bolsa-anal, pero no el estatus socioeconómico.LIMITACIONES:Este estudio retrospectivo incluyó sólo pacientes con seguro comercial.CONCLUSIONES:Un 50,2% de los pacientes se someten a anastomosis ileo-anal y la edad más joven, las comorbilidades más bajas y los casos electivos se asocian con una mayor tasa de colocación de anastomosis ileo-anal. Esto subraya la importancia de asegurar el seguimiento con cirujanos colorrectales para ofrecer la opción de cirugía reparadora, especialmente en pacientes sometidos a colectomías urgentes o emergentes. (Traducción-Dr. Yolanda Colorado ).

The Ileal Pouch-Anal Anastomosis: Identifying Structural Disorders.

Chronic disorders of a pelvic pouch may result from structural complications secondary to postoperative surgical complications which manifest as a variety of symptoms. Knowing the crucial pitfalls of pouch construction can guide treatment options in patients suffering from signs of pouch failure.

Machine Learning and Health Science Research: Tutorial.

Machine learning (ML) has seen impressive growth in health science research due to its capacity for handling complex data to perform a range of tasks, including unsupervised learning, supervised learning, and reinforcement learning. To aid health science researchers in understanding the strengths and limitations of ML and to facilitate its integration into their studies, we present here a guideline for integrating ML into an analysis through a structured framework, covering steps from framing a research question to study design and analysis techniques for specialized data types.