Differential responses of autonomic function in sea level residents, acclimatized lowlanders at & gt;3500  m and Himalayan high altitude natives at & gt;3500  m: A cross-sectional study

Publication date: Available online 9 April 2018 Source:Respiratory Physiology & Neurobiology Author(s): Priyanka Dhar, Vijay K. Sharma, Saroj K. Das, Kalpana Barhwal, Sunil K. Hota, Shashi B. Singh We studied the differential responses of autonomic function in sea level residents (SLR), acclimatized lowlanders (ALH) in high altitude (HA) and HA natives (HAN) at >3500 m. Out of 771 male volunteers included in this cross-sectional study, SLR, ALH and HAN groups were comprised of 351, 307 and 113 volunteers, respectively. Our results showed persistent sympathetic dominance with significantly reduced (p < 0.05) parasympathetic response in ALH as compared to SLR and HAN populations. This may be attributed to significantly increased (p < 0.05) concentration of coronary risk factors and plasma catecholamines in ALH as compared to SLR and HAN. The ALH also showed significantly increased (p < 0.05) level of serum homocysteine as compared to SLR. The HAN exhibited no changes in autonomic function despite significantly elevated (p < 0.05) homocysteine level as compared to SLR. Our findings may have clinical relevance for assessment of susceptibility to cardiovascular risks in HA dwellers, native highlanders and patients with hypoxemia.
Source: Respiratory Physiology and Neurobiology - Category: Respiratory Medicine Source Type: research