Epidemiological study of chronic mountain sickness in natives of Spiti Valley in the Greater Himalayas.
OBJECTIVE
This study determined the prevalence of chronic mountain sickness (CMS) and its predisposing factors among natives of Spiti Valley in the northern state of Indian Himalayas. A cross-sectional survey study was conducted in natives of Spiti Valley aged ≥ 20 years residing at altitudes of 3000 to 4200 meters. CMS was diagnosed using Qinghai criteria. Demographics, behavioral characteristics, specified symptoms of CMS were recorded, including BP, anthropometrics, evidence of RHF, PAH, and severe cyanosis. ECG, echocardiography, PFT, and Sao2 were recorded, and Hb level was estimated with the cyanmethhemoglobin method.


RESULTS
694 subjects free of cardiorespiratory diseases were analyzed. Prevalence of CMS was 28.7%, (95% C.I. of 25.9%-32.8%) and was higher in women than in men (36.6% vs. 15.7%, p<0.001). Erythrocythemia and hypoxemia were recorded in 10.5% and 7.5%, respectively. Age, truncal obesity, female gender, altitude of residence, and physical activity index were independent predictors of CMS with z statistics of 4.2, 2.29, -3.7, 2.8, and -2.8, respectively, and were statistically significant p<0.001. 6.2% of the surveyed population had HAPH.


CONCLUSIONS
28.7% (95% C.I. of 25.9%-32.8%) of the natives of the Spiti Valley in the Indian Himalayas are affected with CMS. Higher prevalence of CMS amongst women needs further studies. Westernized lifestyle appears to have predisposition to CMS.
Department of Cardiology, Indira Gandhi Medical College , Shimla Himachal Pradesh, India .
Prakash Chand
PC
Negi
Sanjeev
S
Asotra
Ravi Kumar
RK
V
Rajeev
R
Marwah
Arvind
A
Kandoria
Neeraj Kumar
NK
Ganju
Rajesh
R
Sharma
Rajeev
R
Bhardwaj
D000328:Adult; D000367:Age Factors; D000531:Altitude; D000532:Altitude Sickness / Q000097:blood / Q000453:epidemiology* / Q000503:physiopathology; D044466:Asian People / Q000706:statistics & numerical data*; D002908:Chronic Disease; D003430:Cross-Sectional Studies; D004906:Erythrocyte Count; D005260:Female; D005541:Forced Expiratory Volume; D006454:Hemoglobins / Q000378:metabolism; D006801:Humans; D000860:Hypoxia / Q000453:epidemiology; D007194:India / Q000453:epidemiology; D008297:Male; D008875:Middle Aged; D009043:Motor Activity; D056128:Obesity, Abdominal / Q000453:epidemiology; D010100:Oxygen / Q000097:blood; D011086:Polycythemia / Q000453:epidemiology; D015995:Prevalence; D012737:Sex Factors; D014797:Vital Capacity
D006454:Hemoglobins; D010100:Oxygen