Cedars-Sinai Medical Center Los Angeles, California
Award: Presidential Poster Award
Connor Stewart, MD1, Janice Oh, MD1, Sepideh Mehravar, MD2, Lauren Schlussel, MD1, Hannah Hackbart, MD1, Bianca Chang, MD1, Ruchi Mathur, MD1, Mark Pimentel, MD, FACG2, Ali Rezaie, MD, MSc, FRCPC3 1Cedars-Sinai Medical Center, Los Angeles, CA; 2Cedars-Sinai Medical Center, West Hollywood, CA; 3Cedars-Sinai Medical Center, Beverly Hills, CA
Introduction: The role of methanogenic archaea is becoming more widely recognized in a variety of gastrointestinal symptoms, including bloating and constipation along with systemic effects. Higher methanogenesis has been reported with aging (Takakura W et al. sci rep.2020). We aimed to characterize demographics of patients with intestinal methanogen overgrowth (IMO) in a large database.
Methods: A retrospective chart review was conducted among patients evaluated at Cedars-Sinai Medical Center with lactulose breath tests from 2005-2022. Patients undergoing their first lactulose breath test were included. A value of ≥10ppm in exhaled breath was considered positive for IMO and a rise of hydrogen ≥20ppm from baseline within 90 minutes was considered positive for hydrogen-predominant small intestinal bacterial overgrowth (SIBO). Patients were categorized by age grouping. Maximal and baseline methane production were compared among those with positive IMO.
Results: We assessed a database of 18,482 lactulose breath tests, of which 16,505 patients (70.7% female; age 47.75 ± 18.53 years, range 2-100 years) were included in analysis after excluding repeat breath tests. Patients with IMO were older than non-IMO patients (Table 1). Prevalence of all IMO increases with age with odds of IMO increasing by 1.8% (OR 1.018; 95%CI 1.016-1.020) (Figure 1A). Male sex was associated with a slight higher risk of IMO (OR 1.095, 95%CI 1.007-1.190). Age is associated with higher maximum methane level (r = 0.15, p < 0.0001) and a higher baseline methane (r = 0.12, p < 0.0001) (Figure 1B).
Discussion: This database represents the largest analysis of SIBO and IMO to date and further supports that IMO positivity increases with age. Additionally, baseline and maximal methane levels increase with age, suggesting a higher burden of methanogen overgrowth as patients age. Association of the phenomenon with aging warrants future mechanistic studies.
Reference: Takakura W, Oh SJ, Singer-Englar T, et al. Comparing the rates of methane production in patients with and without appendectomy: results from a large-scale cohort. Sci Rep. 2020;10(1):867. Published 2020 Jan 21.
Figure: Figure 1A. Breath tests positive for either IMO alone or both SIBO and IMO as a percentage of total breath tests acquired for each age group. Total number of breath tests for each group are included above each group. Figure 1B. Average methane baseline and maximum in all patients with IMO (regardless of SIBO positivity) per age group with standard error bars.
Disclosures:
Connor Stewart indicated no relevant financial relationships.
Janice Oh indicated no relevant financial relationships.
Sepideh Mehravar indicated no relevant financial relationships.
Lauren Schlussel indicated no relevant financial relationships.
Hannah Hackbart indicated no relevant financial relationships.
Bianca Chang: Vibrant Gastro – Consultant.
Ruchi Mathur: 9 meters – Grant/Research Support. Bausch Health – Grant/Research Support. gemelli Biotech – Stock-privately held company.
Mark Pimentel: 9meters – Grant/Research Support, Cedars-Sinai has a licensing agreement with 9meters, Stock Options. Aytu Biosciences – Cedars-Sinai has a licensing agreement with Aytu Biosciences. Bausch Health – Grant/Research Support, Former consultant. Dieta Health – Consultant, Stock Options. Ferring Pharmaceuticals Inc – Consultant. Gemelli Biotech – Cedars-Sinai has a licensing agreement with Gemelli Biotech, Stock Options. Hobbs Medical – Cedars-Sinai has a licensing agreement with Hobbs Medical. Salvo Health – Consultant, Stock Options. Synthetic Biologics (now Theriva) – Grant/Research Support, Stock Options. Vivante Health Inc. – Consultant, Stock Options.
Connor Stewart, MD1, Janice Oh, MD1, Sepideh Mehravar, MD2, Lauren Schlussel, MD1, Hannah Hackbart, MD1, Bianca Chang, MD1, Ruchi Mathur, MD1, Mark Pimentel, MD, FACG2, Ali Rezaie, MD, MSc, FRCPC3. P2627 - Association of Excess Methanogenesis With Age and Sex: A Large Scale Database Analysis, ACG 2023 Annual Scientific Meeting Abstracts. Vancouver, BC, Canada: American College of Gastroenterology.
