Negi P C, Bhardwaj Rajeev, Kandoria Arvind, Asotra Sanjeev, Ganju Neeraj, Marwaha Rajeev, Sharma Rajesh, Kanwar Anubhav
Deptt. of Cardiology, Indira Gandhi Medical College, Shimla 171001, Himachal Pradesh.
J Assoc Physicians India. 2012 Jun;60:21-5.
Hypertension is the result of interaction between genetic vulnerability and exposure to unhealthy lifestyle. However, studies investigating the impact of cardiovascular adaptive response to hypobaric hypoxia and extreme cold in natives of high altitude on the development of hypertension have yielded conflicting results. A community based cross-sectional study was carried out in an unique population of Spiti valley of Greater Himalayas residing at an altitude of 3100-3500 m (group 1) and 3500 m and above (group 2) to evaluate the impact of altitude of residence on prevalence of hypertension. 413 subjects, age 20 years and above were selected by stratified cluster random sampling technique and screened for recording socio-demographic profile, anthropometrics, fasting blood sugar and blood pressure. There was no significant difference in the mean age (40.1 vs.38.0 years) and gender distribution (65.7% vs. 61.4% females) between the two groups. The overall prevalence of hypertension was 22.5% and achieved higher significance in group 1 (27.5%) compared to group 2 (19%); p < 0.041. The socioeconomic profile and lifestyle of group from higher altitude was significantly different with people being less educated, agriculture as main occupation compared to the group at lower altitude. On comparison, the same group had a lower prevalence of obesity 17.4% vs. 35.9% (p < 0.000), Diabetes 0.4% vs. 4.1% (p < 0.03) and impaired fasting glucose 5% vs. 11.1% (p < 0.06). Obesity, age and altitude of residence were significantly associated as independent predictors of prevalence of hypertension in this study. Hypobaric hypoxia thus appears to have a protective effect from developing hypertension. The prevalence of hypertension in natives of Spiti valley is thus influenced by lifestyle related risk factors, age and possibly altitude of residence.
高血压是遗传易感性与不健康生活方式相互作用的结果。然而，关于高海拔地区原住民心血管对低压缺氧和极端寒冷的适应性反应对高血压发展影响的研究结果相互矛盾。在大喜马拉雅山脉斯皮提山谷的一个独特人群中开展了一项基于社区的横断面研究，该人群居住在海拔3100 - 3500米（第1组）和3500米及以上（第2组），以评估居住海拔对高血压患病率的影响。采用分层整群随机抽样技术选取了413名20岁及以上的受试者，并对其社会人口学特征、人体测量学指标、空腹血糖和血压进行记录筛查。两组之间的平均年龄（40.1岁对38.0岁）和性别分布（女性分别为65.7%对61.4%）无显著差异。高血压的总体患病率为22.5%，第1组（27.5%）比第2组（19%）具有更高的显著性；p < 0.041。与低海拔组相比，高海拔组的社会经济状况和生活方式有显著差异，教育程度较低，以农业为主要职业。相比之下，同一组的肥胖患病率较低（17.4%对35.9%，p < 0.000）、糖尿病患病率较低（0.4%对4.1%，p < 0.03）以及空腹血糖受损患病率较低（5%对11.1%，p < 0.06）。在本研究中，肥胖、年龄和居住海拔作为高血压患病率的独立预测因素显著相关。因此，低压缺氧似乎对高血压的发生具有保护作用。斯皮提山谷原住民的高血压患病率因此受到生活方式相关风险因素、年龄以及可能的居住海拔的影响。
