Met-Pro Study

  • Research type

    Research Study

  • Full title

    Met-Pro Study: The role of METhanogens in the PROgression of Parkinson's disease and related neurological conditions

  • IRAS ID

    358942

  • Contact name

    Marta Camacho

  • Contact email

    msc72@cam.ac.uk

  • Sponsor organisation

    CAMBRIDGE UNIVERSITY HOSPITALS NHS FOUNDATION TRUST

  • Duration of Study in the UK

    3 years, 0 months, 1 days

  • Research summary

    Intestinal methanogen overgrowth (IMO), associated with archaea (a type of microorganism) in the gut, has been found to be more prevalent in Parkinson’s disease (PD) when compared to controls and associated with constipation and worse motor function. Constipation is a risk factor for PD dementia, but the association between breath methane levels and cognition in PD has not been investigated. Pilot data has shown that methane levels were associated with delayed whole gut transit time and with higher faecal archaeal abundance in PD. Moreover, methane levels correlated with worse cognition, particularly memory scores in both PD patients and controls. This study aims to validate these findings in a large cohort of people with PD, people with a high risk of developing PD, healthy controls and people with other neurodegenerative disorders and to investigate whether non-invasive breath tests warrant further investigation as a biomarker in PD cognition and other related neurodegenerative diseases. Moreover, the mechanistic link between methane-producing archaea (‘methanogens’) and cognition, and the possible role of gut and systemic inflammation in this, is unknown. This study will also investigate the effect of L. reuteri, a probiotic which inhibits methanogens, on breath methane levels, faecal archaeal abundance, inflammation and gut function markers in high methane producing PD participants. If the findings are positive, this will validate methane breath tests as a biomarker in PD and lay the groundwork for a future randomised controlled trial of methanogen inhibitors.

  • REC name

    London - Queen Square Research Ethics Committee

  • REC reference

    25/LO/0615

  • Date of REC Opinion

    9 Sep 2025

  • REC opinion

    Further Information Favourable Opinion