GLP-1 Receptor Agonists and Early Proctologic Effects in Morbid Obesity

Glucagon-like peptide-1 receptor agonists (GLP-1 RAs) are increasingly used in the treatment of obesity and type 2 diabetes mellitus. Although gastrointestinal adverse effects such as constipation, diarrhea, nausea, delayed gastric emptying, and altered bowel habits are well recognized, their potential impact on anorectal symptoms and proctologic diseases remains poorly investigated.

Changes in bowel habits and stool consistency associated with GLP-1 RA therapy may contribute to the development or progression of anorectal disorders including hemorrhoidal disease, anal fissures, perianal irritation, pruritus ani, and fecal incontinence. However, prospective clinical data evaluating these associations are lacking.

This prospective observational cohort study aims to evaluate the early proctologic effects of GLP-1 receptor agonist therapy in morbidly obese patients. Participants who are newly prescribed GLP-1 RA treatment will undergo baseline assessment before treatment initiation and follow-up evaluation at 3 months.

Baseline evaluation will include demographic characteristics, comorbidities, bowel habit assessment, anorectal symptom assessment, and standardized proctologic examination including perianal inspection, digital rectal examination, and anoscopy. Follow-up evaluation at 3 months will reassess symptoms and repeat proctologic examination.

The primary objective is to determine the incidence of newly developed proctologic diseases during the first 3 months after initiation of GLP-1 receptor agonist therapy. Secondary objectives include evaluating changes in anorectal symptom severity, bowel habits, progression of pre-existing anorectal disease, and the relationship between weight loss magnitude and anorectal symptoms.

Inclusion criteria

• Age ≥18 years
• Morbid obesity (BMI ≥40 kg/m² or BMI ≥35 kg/m² with obesity-related comorbidities)
• Newly prescribed GLP-1 receptor agonist therapy
• Ability and willingness to provide written informed consent
• Ability to attend 3-month follow-up visit

Exclusion criteria

• Inflammatory bowel disease
• Perianal Crohn's disease
• History of anorectal malignancy
• Previous pelvic radiotherapy
• Anorectal surgery within the previous 3 months
• Pregnancy
• Neurogenic bowel dysfunction
• Inability to comply with follow-up visits
• Discontinuation of GLP-1 receptor agonist therapy before follow-up assessment
• Active anorectal infection or abscess