Orang Asli Health and Lifeways Project (OA HeLP): Study Protocol
Authors: Wallace Ian J. , Lea Amanda J. , Lim Yvonne A. L. , Chow Steven K. W. , bin Mohd Sayed Izandis , Ngui Romano , Haji Shaffee Mohd Tajudin , Ng Kee-Seong , Nicholas Colin , Venkataraman Vivek V. , Kraft Thomas S. 
Published: October 2021

Introduction

Non-communicable disease (NCD) risk is influenced by environmental factors that are highly variable worldwide, yet prior research has focused mainly on high-income countries where most people are exposed to relatively homogenous and static environments. Understanding the scope and complexity of environmental influences on NCD risk around the globe requires more data from people living in diverse and changing environments. Our project will investigate the prevalence and environmental causes of NCDs among the indigenous peoples of Peninsular Malaysia, known collectively as the Orang Asli, who are currently undergoing varying degrees of lifestyle and sociocultural changes that are predicted to increase vulnerability to NCDs, particularly metabolic disorders and musculoskeletal degenerative diseases.

Methods

Biospecimen sampling and screening for a suite of NCDs (e.g., cardiovascular disease, type II diabetes, osteoarthritis, osteoporosis), combined with detailed ethnographic work to assess key lifestyle and sociocultural variables (e.g., diet, physical activity, technology usage), will take place in Orang Asli communities spanning a gradient from remote, traditional villages to acculturated, market-integrated urban areas. Analyses will, first, test for relationships between environmental variables, NCD risk factors, and NCD occurrence to investigate how environmental changes are affecting NCD susceptibility among the Orang Asli. Second, we will examine potential molecular and physiological mechanisms (e.g., epigenetics, systemic inflammation) that mediate environmental effects on health. Third, we will identify intrinsic (e.g., age, sex) and extrinsic (e.g., early life experiences) factors that predispose certain people to NCDs in the face of environmental change to better understand which Orang Asli individuals are at greatest risk of NCDs.

Ethics

Approval was obtained from multiple ethical review boards including a committee at the Malaysian Ministry of Health. This study follows established principles for ethical biomedical research among vulnerable indigenous communities, including fostering collaboration, building cultural competency, enhancing transparency, supporting capacity building, and disseminating research findings.

Strengths and Limitations of This Study

Environmental influences on non-communicable disease (NCD) risk are understudied outside of high-income countries, particularly among societies transitioning from traditional, non-industrial lifestyles to market-integrated, urban lifestyles.

This multidisciplinary project aims to better understand how rapid lifestyle and sociocultural changes are affecting NCD risk among the indigenous peoples of Peninsular Malaysia, known collectively as the Orang Asli.

More broadly, this project aims to provide insights useful for understanding the rising prevalence of NCDs in other low- and middle-income countries and societies experiencing rapid environmental changes.

This project might be limited by the SARS-CoV-2 pandemic.