CHAPTER 7 Age Trends in Blood Pressure and Obesity among the Urban Bhutias of Sikkim Sobhanjan Sarkar and Barun Mukhopadhyay INTRODUCTION Many studies have revealed that age is an important factor with which the cardiovascular disease (CVD) risk factors are related (Eisenmann and Malina 2002; Guo et al., 1999). Fact remains that the problems of high blood pressure (essential hypertension) and obesity considered to be the major risk factors for CVD are increasingly assuming global importance (Stevenson, 1999; WHO, 2000). Clearly, essential hypertension happens to be one of the most prevalent disorders in the industrialized world. Further, according to an estimate, over 150 million individuals in the United States, India and China have at or above the WHO recommended threshold value (Reddy, 1996; National Center for Health Statistics, 1977). Many studies, most of which were conducted before 1972, have found that in some human groups blood pressure increases insignificantly or not at all. These groups were mostly traditional and non-western relatively isolated tribal/indigenous populations. Needless to say lifestyle changes have occurred in the last three decades in many different ways among majority of populations inhabiting diffe- rent parts of the world. And as a consequence, increase in blood pressure with age has been a feature for many populations in developed and developing nations. The positive influences of high sodium and high fat diet, urban living, stress and so on with age could be the operational factors (Waldron et al., 1982). A few studies among the American women demonstrate that with increasing age there is an increasing accumu- lation of body fat and blood pressure (Wing et al., 1991; Dawson-Hughes and Harris 1992). Some cross-sectional studies have shown that among different populations age related changes in anthropometric and behavioural traits like phy- sical activity occur (Poehlman et al., 1995; Pasquali et al., 1994). A study among the migrant Pakistani men in UK also shows the relationship between age and other anthropometric and clinical traits (Bose and Mascie-Taylor, 1997). In Indian context, death caused by CVD is increased to 33% in 1990s from 4% in 1960s and is on the threshold of an epidemic (WHO, 1993). Like other developing countries, India is also undergoing changes owing to the forces of modernisation, which are affecting the health of many Indians adversely. In India age related changes regarding obesity and blood pressures have recently been shown by a study among the elderly Bengalees of Kolkata (Ghosh et al., 2001). Some authors have also studied different Indian populations and found age and sex variations in blood pressure and obesity measures (Majumder et al., 1994; Dalal, 1978). Most of the studies regarding age related changes in obesity, hyper- tension in India were conducted among the non- tribal populations while studies among the tribal groups are rare. However, a study among a tribal population, considering the age range between 18 and 75 years, of Andhra Pradesh shows an increasing trend in BMI values with increasing age (Reddy, 1998). Recently, another study conducted in the Sikkim Himalayan region among the Lepchas, a tribal community, observed age related changes in diastolic blood pressure (DBP) (Mukhopadhyay and Mukhopadhyay, 2001). In view of the above, the aim of the present paper is to examine the age related changes in blood pressure and obesity measures among the ‘Bhutias’, a tribal community of Sikkim. MATERIALS AND METHODS For the present study, the Bhutias, residing in the town of Gangtok and its neighbourhood, are considered as the study participants. The Bhutias are of Mongoloid origin. They have a language of their own which is known as ‘Sikkimese’. However they also speak in Nepali. Many Bhutias especially the educated section can speak Hindi and English as well. In the middle of 17 th century the Bhutias started coming to Sikkim from Tibet (Dutta, 1991). The main occupation of the Bhutias living in the rural areas is agriculture while the urban Bhutias are predominantly engaged in service and business. After the merger of Sikkim with the Indian Union