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Human Life, Aging, and Disease in High-Altitude Environments:
Physio-medical, Ecological and Cultural Adaptation in “Highland Civilizations”
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| okumiya Kiyohito RIHN |
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| sakamoto Ryota RIHN |
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ando Kazuo Center for Southeast Asian Studies, Kyoto University
inamura Tetsuya School of Foreign Studies, Aichi Prefectural University
kawai Akinobu Faculty of Liberal Arts, The Open University of Japan
kosaka Yasuyuki RIHN
shigeta Masayoshi Graduate School of Asian and African Area Studies, Kyoto University
takeda Shinya Graduate School of Asian and African Area Studies, Kyoto University
tsukihara Toshihiro Faculty of Education and Regional Studies, University of Fukui
matsubayashi Kozo Center for Southeast Asian Studies, Kyoto University |
This project examines how humans have adapted to high-altitude environments physiologically, ecologically and culturally. Project researchers document the health status of elderly highlanders, and explore possible factors associated with lifestyle-related diseases in this population. Finally, we investigate the impact of modern development over the past 50 years on high altitude lifestyles and environments, and assess how these changes affect the quality of life (QOL) of elderly highlanders. Study sites have been selected from four areas in the Himalaya-Tibet region, the Ladakh region in India, the Arunachal Pradesh State in India, Khaling in Bhutan, and the Qinghai Province in China, and each of which has distinct ecological and socioeconomic conditions.
Project Objectives
This project explores new perspectives on human lifestyle in high-altitude environments where oxygen levels are low and natural resources are limited. Project research focuses on aging problems and lifestyle-related diseases, which are regarded as manifestations of global environmental issues evident in the human body. We aim to clarify the concept of “highland civilization”, defined in relation to social, ecological and cultural adaptations to high-altitude environments, and to examine human physiological adaptations to high altitude environments and how recent changes in lifestyle have affected the health and quality of life (QOL) of the elderly.
Figure 1 Vertical distribution pattern of edible and medicinal plants
(click to see bigger image)
Trade networks of ethnic groups distributed important edible and medicinal plants throughout the steep Arunachal Pradesh landscape (Kosaka et al., 2011).
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Figure 2 Agro-pastoral linkage
Transhumance of Ladakh pastoralists is closely linked to the agricultural cycle at each settlement of different altitudes (Hirata 2011). |
Ecological and cultural adaptation to the high-altitude environment and recent lifestyle change
Subsistence lifestyle and economic conditions were studied in three ecologically distinct zones in Himalaya-Tibet region: a forest in Arunachal Pradesh and Bhutan, the Ladakh oasis, and the grasslands of Qinghai. Distribution of vegetation, ethnic groups, patterns of subsistence and alien plant invasion were described from 200 to 4000 m in Arunachal Pradesh (Kosaka 2010). Detailed household interviews and analysis of satellite imagery revealed a recent decrease in the number of livestock, increasing use of chemical fertilizer, and an expanding pattern of abandoned land at Domkhar village in Ladakh (Fig. 4). Shortage of fodder, heavy snowfall, and limited access to social services were identified as causes of outmigration of pastoral people from the Changthang highland to Leh city in Ladakh. In Ladakh, researchers assessed the risk of glacial lake collapse, documented damage due to flood (Yamaguchi 2011) and analyzed the role of climate as a cause of natural disaster (Fig. 3).
Figure 3 Vulnerability and flexibility in relation to disaster
Analysis of weather-monitoring data indicated the vulnerability of less vegetated oasis zones to mudflow disaster even with moderate rainfall in Ladakh (Yatagai et al., 2011). On the other hand, health examinations detected fewer mental stresses among disaster victims there than in other regions, which suggested a psychological coping capacity related to the sense of value and flexible social support in Ladakh (Ishikawa 2011). |
Figure 4 Land use in a household with cases of lifestyle-related diseases
This household in Ladakh had one case with polycythemia and high blood sugar and another case with obesity and hypertension. Nutritional survey revealed high intake of carbohydrate, lipid and salt. A land use survey revealed cultivation of cash crops and abandoned land related to labor shortage. Elderly agro-pastoral people adapted to hypoxic conditions suffered from lifestyle-related diseases associated with changes of diet and activity (Nose, Takeda 2011, Fukutomi, and Kimura 2011). |
The “Himalaya model of lifestyle-related diseases”: Interaction between long-term physiological high-altitude adaptation and recent lifestyle change
We have documented a relationship between physiological hypoxic adaptation and lifestyle-related diseases. Han people had higher hemoglobin concentration compared with Tibetans in Qinghai. Increasing prevalence of diabetes mellitus was strongly associated with increases in hemoglobin levels related to adaptation to hypoxia in Ladakh, Yushu, and Arunachal (Okumiya 2010).
There is association between high-altitude and lifestyle-related diseases. High blood sugar, pulmonary disorder caused by dust, sleep disorder (in Ladakh), hypertension and hyperlipidemia (in Arunachal) were more prevalent among higher-altitude dwelling people (Ishimoto 2011).
There was association between ecological context, globalization and food diversity. Food diversity was highest in humid Arunachal, moderate in semi-arid Qinghai and lowest in arid Ladakh. Rural areas in Ladakh show less food diversity than urban areas.
There was association between settlement, livelihood change and lifestyle-related diseases. Lifestyle-related diseases were more prevalent in urban area of Yushu than rural area of Haiyan in Qinghai (Okumiya 2010). Official workers and monks had higher prevalence of obesity, hypertension and diabetes than agro-pastoral local people in urban areas of Yushu and Leh.
The prevalence of diabetes was low among pastoral peoples following the traditional lifestyle in Arunachal and Haiyan (3000 m. altitude). In Ladakh (2900-3800 m) the prevalence of prediabetes in Ladakh was high, however. The difference may be related to the scarcity of natural resources in Ladakh, and their fragility in relation to contemporary change in lifestyle. There was greater prevalence of high hemoglobin level and high blood sugar with obesity and hypertension in Yushu (3600 m) than in Ladakh. Rapid change of lifestyle in hypoxia-adapted people may accelerate lifestyle-related diseases, as according to our “Diabetes-acceleration hypothesis” (Fig. 5).
Figure 5 Diabetes acceleration hypothesis
In high altitude Himalaya regions, after rapid changes in lifestyle, adaptation mechanisms to hypoxia and low nutrition may have accelerated the onset and aggravation of diabetes. This is “the Himalaya model of lifestyle-related diseases” -“diabetes acceleration hypothesis” (Okumiya 2011). |
Aging with high QOL: Health care design for the highland elderly
With the collaboration of local health staff in Ladakh we initiated follow-up monitoring of blood pressure, body weight and amount of exercise (Photo 1). Comprehensive geriatric functional analysis in all elderly people in Khaling, Bhutan was conducted and we are developing a geriatric care system in collaboration with local health staff, including traditional medical practitioners and monks, to promote health, high spirituality and quality of life (Sakamoto 2011).
Photo 1 Local participants and health staff in a medical camp in Domkhar, Ladakh
Follow up monitoring of body weight, physical activity and blood pressure is now underway. |
Schedule in 2011/2012
Global environmental changes associated with socioeconomic globalization and climate warming are manifest in the human bodies of highland peoples. In the coming period of research, we will examine the difference between adaptation and maladaptation in relation to our hypotheses of Himalaya lifestyle-related diseases and diabetes acceleration. In this task, we will continue to integrate the research and findings of the medical and cultural/ecological teams. In describing a model of health care that is culturally and ecologically suited to the challenges of highland civilizations, and that is based in the wisdom of the elderly concerning quality of life, aging, and death, we will reflect on present lifestyles and the future of not only highland civilization but also modern civilization.
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