Cardio-metabolic health risks in indigenous populations of Southeast Asia and the influence of urbanization

Abstract

BackgroundSouth East Asia (SEA) is home to over 30 tribes of indigenous population groups who are currently facing rapid socio-economic change. Epidemiological transition and increased prevalence of non-communicable diseases (NCD) has occured. In Peninsular Malaysia, the Orang Asli (OA) indigenous people comprise 0 · 6% (150,000) of the population and live in various settlements. OA comprise three distinct large tribes with smaller sub-tribes. The three large tribes include Proto-Malay (sub-tribes: Orang Seletar and Jakun), Senoi (sub-tribes: Mahmeri and Semai), and Negrito (sub-tribes: Jehai, Mendriq and Batek).MethodsWe studied the health of 636 OA from seven sub-tribes in the Peninsular. Parameters that were assessed included height, weight, BMI and waist circumference whilst blood pressure, cholesterols, fasting blood glucose and HbA1c levels were recorded. We then analysed cardio-metabolic risk factor prevalences and performed multiple pair-wise comparisons among different sub-tribes and socio-economic clusters.ResultsCardio-metabolic risk factors were recorded in the seven sub-tribes.. Prevalence for general and abdominal obesity were highest in the urbanized Orang Seletar (31 · 6 ± 5 · 7%; 66 · 1 ± 5 · 9%). Notably, hunter gatherer Jehai and Batek tribes displayed the highest prevalence for hypertension (43 · 8 ± 9 · 29% and 51 · 2 ± 15 · 3%) despite being the leanest and most remote, while the Mendriq sub-tribe, living in the same jungle area with access to similar resources as the Batek were less hypertensive (16.3 ± 11.0%), but displayed higher prevalence of abdominal obesity (27.30 ± 13.16%).ConclusionsWe describe the cardio-metabolic risk factors of seven indigenous communities in Malaysia. We report variable prevalence of obesity, cholesterol, hypertension and diabetes in the OA in contrast to the larger ethnic majorities such as Malays, Chinese and Indians in Malaysia These differences are likely to be due to socio-economic effects and lifestyle changes. In some sub-tribes, other factors including genetic predisposition may also play a role. It is expected that the cardio-metabolic risk factors may worsen with further urbanization, increase the health burden of these communities and strain the government’s resources.

Health and saliva microbiomes of a semi-urbanized indigenous tribe in Peninsular Malaysia

“…We reported a high prevalence of cardio-metabolic diseases such as obesity, pre-diabetes, insulin resistance and pre-hypertension among Temiar. These non-communicable diseases were previously not reported in OA, but recent studies have indicated their high prevalence, especially in OA tribes living near cities 1,3,15 . Increased cardio-metabolic risks were also reported in aboriginal Torres Straits Islanders from Australia 16 , the Jaguapiru indigenous community in Brazil 17 and the Rang Bothiya tribe in India 18 .…”

“…They are categorized into three main groups, namely Negrito, Senoi and Proto Malay. OAs are widely spread across the Peninsular and range from semi-nomadic deep forest hunter-gatherers such as the Jahai to resettled communities such as Mah Meri to urbanized city-fringe dwellers such as Orang Seletar 1 . This study focused on the Temiar who are a subtribe of Senoi and are believed to be descendants of the first Neolithic farmers who migrated to the Malay Peninsula 2 .…”

“…As the OA became more urbanized and by large left their ancestral habitats and practices, they led more sedentary lifestyles. These factors, coupled with loss of access to forest resources and increasing pressures to turn to store-bought food, may largely explain the rise in cardio-metabolic diseases such as hypertension, diabetes and obesity shown in recent studies 1,3,4 .…”

Do not neglect the indigenous peoples when reporting health and nutrition issues of the socio-economically disadvantaged populations in Malaysia

“…While underweight and stunting are common in Orang Asli children, overweight and obesity are becoming increasingly prevalent among the adults. Studies across the sub-tribes showed that approximately 10-50% Orang Asli adults were overweight and/or obese, with women more likely to be overweight or obese than men [39][40][41][42][43]. There is also accumulating evidence of metabolic risks (i.e.…”

“…There is also accumulating evidence of metabolic risks (i.e. impaired glucose intolerance, hypertension, central obesity, hyperlipidaemia) in the Orang Asli adults [41][42][43][44][45][46]. The rising prevalence of metabolic risks could lead to increasing occurrence of diabetes mellitus, hypertension and cardiovascular diseases in the indigenous community.…”