Effect of aging on blood pressure in Leh, Ladakh, a high-altitude (3524 m) community, by comparison with a Japanese town.

The effect of aging on blood pressure (BP) and heart rate (HR) was investigated in a cross-sectional study in the high-altitude community of Leh, Ladakh (altitude: 3524 m) and a Japanese community in U town, Hokkaido (altitude: 25 m). BP and HR were obtained in a sitting position from 332 subjects 13-81 years of age in Ladakh, and from 216 Japanese citizens, 24-79 years of age. Measurements were taken after a 2-min rest, using a semi-automated BP device (UA-767 PC, A and D Co. LTD, Tokyo). High-altitude people showed higher diastolic BP and HR values than lowland people (83.2 vs. 76.9 mmHg and 78.6 vs. 69.2 bpm, P < 0.001), but no difference in systolic BP. Highland people also showed a steeper BP increase with age than the lowland people (systolic BP: 0.7476 vs. 0.3179 mmHg/year, P < 0.0005; diastolic BP: 0.3196 vs. 0.0750 mmHg/year, P < 0.001). This chronoecologic investigation in Ladakh examined the circulation as a physiological system at high-altitude. Our data indicate the need for a more comprehensive cardiovascular assessment for a better diagnosis and a more fruitful treatment. Longitudinal observations of effects of socio-ecologic factors on the cardiovascular system should help prevent strokes and other cardiovascular events, especially at high altitude.

Chronoecological health watch of arterial stiffness and neuro-cardio-pulmonary function in elderly community at high altitude (3524 m), compared with Japanese town.

Effects of high altitude on arterial stiffness and neuro-cardio-pulmonary function were studied. Blood pressure (BP) and heart rate (HR) were measured in a sitting position on resting Ladakhis, living at an altitude of 3250-4647 m (Phey village, 3250 m: 17 men and 55 women; Chumathang village, 4193 m: 29 men and 47 women; Sumdo village, 4540 m: 38 men and 57 women; and Korzok village, 4647 m: 84 men and 70 women). The neuro-cardio-pulmonary function, including the Kohs block design test, the Up and Go, the Functional Reach and the Button tests, was examined in 40 elderly subjects (19 men and 21 women, mean age: 74.7 +/- 3.3 years) in Leh, Ladakh (altitude: 3524 m), for comparison with 324 elderly citizens (97 men and 227 women, mean age: 80.7 +/- 4.7 years) of Tosa, Japan (altitude: 250 m). Cardio-Ankle Vascular Index (CAVI) was measured as the heart-ankle pulse wave velocity (PWV) in these subjects using a VaSera CAVI instrument (Fukuda Denshi, Tokyo). SpO(2) decreased while Hb and diastolic BP increased with increasing altitude. At higher altitude, residents were younger and leaner. Women in Leh vs. Tosa had a poorer cognitive function, estimated by the Kohs block design test (3.7 +/- 3.6 vs. 16.4 +/- 9.6 points, P < 0.0001) and poorer ADL functions (Functional Reach: 13.7 +/- 7.0 cm vs. 25.3 +/- 8.7 cm, P < 0.0001; Button test: 22.5 +/- 4.8 vs. 14.8 +/- 5.7 s, P < 0.0001). Time estimation was shorter at high altitude (60-s estimation with counting: 41.1% shorter in men and 23.0% shorter in women). A higher voltage of the QRS complex was observed in the ECG of Leh residents, but two times measurement of CAVI showed no statistically significant differences between Leh and Tosa (two times of CAVI measures; 9.49 vs. 10.01 m/s and 9.41 vs. 10.05 m/s, respectively), suggesting that most residents succeed to adapt sufficiently to the high-altitude environment. However, correlation of CAVI with age shows several cases who show an extreme increase in CAVI. Thus, for the prevention of stroke and other adverse cardiovascular outcomes, including dementia, CAVI may be very useful, especially at high altitude. In conclusion, elderly people living at high altitude have a higher risk of cardiovascular disease than low-latitude peers. To determine how these indices are associated with maintained cognitive function deserves further study by the longitudinal follow-up of these communities in terms of longevity and aging in relation to their neuro-cardio-pulmonary function.