Helicobacter Pylori Infection and Gastric Diseases in Lao PDR: First Community-Wide Population-Based Study

A Community-based Collaborative Study for Eradication of Helicobacter Pylori and Associated Gastric Cancer in Luangprabang and Champasak Province, in Lao PDR 2025.

This study aims to determine the regional prevalence of Helicobacter pylori infection, bacterial strain differences, and the prevalence of gastric cancer in two provinces of Laos, a multi-ethnic country where these factors may vary by region and ethnicity. The study also evaluates whether H. pylori eradication therapy contributes to disease prevention. Residents aged 18 years or older in Luang Prabang Province and Champasak Province underwent stool antigen testing, and H. pylori-positive individuals received eradication therapy. High-risk participants aged ≥40 years underwent upper gastrointestinal endoscopy for early detection of gastric cancer.

Study Overview

• Status: Completed
• Conditions: Helicobacter Infections; Prevention and Control; Gastric Cancer Screening; Helicobacter Eradication

Detailed Description

This population-based study was conducted in Laos to investigate geographic variation in Helicobacter pylori infection, bacterial strains, and the prevalence of precancerous and cancerous gastric lesions. Laos is a multi-ethnic nation, and differences in H. pylori prevalence and strain distribution are expected across ethnic groups and regions. The goal of this study is to assess the current burden of infection and evaluate the effectiveness of eradication therapy as a preventive strategy for gastric cancer.

Eligible participants were residents aged ≥18 years living in Luang Prabang Province (North) and Champasak Province (South). The study received approval from the Ethics Committee of the Ministry of Health of Laos. All participants received an explanation of the risks and benefits of screening and provided written informed consent.

The study procedures were conducted as follows:

1. Stool H. pylori antigen rapid test was performed for all enrolled participants.
2. Participants aged ≥40 years who tested positive were considered a high-risk group and underwent upper gastrointestinal endoscopy for early detection of precancerous gastric lesions and gastric cancer.
3. All H. pylori-positive participants received 14-day triple therapy consisting of lansoprazole, amoxicillin, and clarithromycin.
4. Eradication was assessed using a follow-up stool antigen test at 8 months after treatment in Luang Prabang Province and 6 months after treatment in Champasak Province.

Screening in Luang Prabang Province was conducted between December 2023 and October 2024, and screening in Champasak Province between October 2024 and June 2024.

• Study Type: Observational
• Enrollment (Actual): 1251

Contacts and Locations

Study Locations

• Laos
  • Capital
    • Vientiane, Capital, Laos, 0100
      • National Cancer Center

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult; Older Adult
• Accepts Healthy Volunteers: Yes

• Sampling Method: Non-Probability Sample

Study Population

Study Locations

1. Luangprabang Province, Lao PDR
2. Champasak Province, Lao PDR

Description

Inclusion Criteria:

• Age ≥18 years
• Resident of Luangprabang or Champasak Province
• Able to provide written informed consent

Exclusion Criteria:

• Severe comorbidities contraindicating screening or treatment
• Allergy to medications used in triple therapy
• Pregnant or breastfeeding women (if applicable)

Study Plan

How is the study designed?

Number of groups / cohorts

2

Cohorts and Interventions

Group / Cohort
Residents of Luang Prabang Province; Residents aged ≥18 years in Luang Prabang Province who underwent stool antigen testing for H. pylori. Participants ≥40 years who tested positive additionally underwent upper endoscopy. All positive individuals received triple therapy and were followed for eradication.
Residents of Champasak Province; Residents aged ≥18 years in Champasak Province who underwent stool antigen testing for H. pylori. Participants ≥40 years who tested positive additionally underwent upper endoscopy. All positive individuals received triple therapy and were followed for eradication.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Prevalence of H. pylori infection • Method: Stool antigen test • Time Frame: Baseline	The proportion of participants who test positive for H. pylori infection using a stool antigen rapid test at baseline. All enrolled residents aged ≥18 years in Luang Prabang Province and Champasak Province undergo stool antigen testing. H. pylori positivity is defined according to the manufacturer's validated cutoff value. This measure provides a population-based estimate of the current H. pylori infection prevalence in two geographically distinct regions of Laos.	Baseline

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
H. pylori eradication rate after triple therapy,	The percentage of H. pylori-positive participants who achieve eradication following 14-day triple therapy, confirmed by stool antigen testing.	6-8 months after treatment completion,

Other Outcome Measures

Outcome Measure	Measure Description	Time Frame
Prevalence of gastric cancer	Number of gastric cancer detected during screening endoscopy among high-risk participants (≥40 years, H. pylori positive).	Baseline endoscopy

Collaborators and Investigators

• Sponsor: Zero Helicobacter IGAN Network
• Collaborators: Oita University; Setthathirath Hospital; Mahosot Hospital, Laos; Lao National Cancer Center

Study record dates

Study Major Dates

• Study Start (Actual): December 18, 2023
• Primary Completion (Actual): October 10, 2024
• Study Completion (Actual): June 7, 2025

Study Registration Dates

• First Submitted: December 19, 2025
• First Submitted That Met QC Criteria: January 13, 2026
• First Posted (Actual): January 14, 2026

Study Record Updates

• Last Update Posted (Actual): January 14, 2026
• Last Update Submitted That Met QC Criteria: January 13, 2026
• Last Verified: January 1, 2026

More Information

Terms related to this study

• Keywords: gastric cancer; helicobacter pylori; cancer prevention; Laos; H pylori eradication
• Additional Relevant MeSH Terms: Neoplasms by Site; Neoplasms; Infections; Gastrointestinal Neoplasms; Digestive System Neoplasms; Digestive System Diseases; Gastrointestinal Diseases; Stomach Diseases; Bacterial Infections; Bacterial Infections and Mycoses; Gram-Negative Bacterial Infections; Stomach Neoplasms; Helicobacter Infections
• Other Study ID Numbers: 1015/REC

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO
• IPD Plan Description: Individual participant data will not be shared. Due to ethical and regulatory considerations in Laos, and because the dataset includes sensitive health information collected from community residents, de-identified participant-level data will not be made publicly available.

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No