Hypertension status and its risk factors in highlanders living in Ganzi Tibetan Plateau: a cross-sectional study.

BACKGROUND

The updated status of hypertension and its risk factors are poorly evaluated in Tibetan highland areas. We initiated a large-scale cross-sectional survey to provide updated status of hypertension and its risk factors (especially salt intake) in the Ganzi Tibetan Plateau, China.

METHODS

Stratified multistage random sampling was performed to obtain a representative sample of 4,036 adult residents from 4 counties in the Ganzi Tibetan area. The whole survey population was used to present the epidemiology and risk factors of hypertension. The participants with blood and urine biochemistry data were used to analyze the relationship between salt intake parameters and hypertension.

RESULTS

Stratified multistage random sampling was performed to obtain a representative sample of 4,036 adult residents. The overall prevalence rate of hypertension was 33.5% (the age-adjusted prevalence rate was 28.9%). A total of 50.9% of the hypertensive patients knew their conditions; 30.1% of them received antihypertensive treatment; and 11.2% of them had their blood pressure controlled. Age, male sex, living altitude ≥ 3500 m, overweight and abdominal obesity were positively correlated with hypertension. In addition, the adjusted odds ratio (OR) for hypertension was 1.33 (95% CI: 1.01-1.74) for drinking tea with salt, and 1.51 (95% CI: 1.32-1.72) for per SD increase in the estimation of 24-hour urinary sodium excretion (e24hUSE). Furthermore, per 100mmol/day increase in e24hUSE was associated with elevation of blood pressure (+ 10.16, 95% CI: 8.45-11.87 mmHg for SBP; +3.83, 95% CI: 2.74-4.93 mmHg for DBP) in this population.

CONCLUSIONS

Our survey suggests a heavy disease burden of hypertension in the Ganzi Tibetan Plateau. Age, male sex, altitude of residence ≥ 3500 m, overweight, abdominal obesity, and excessive salt intake (shown as drinking tea with adding salt and a higher level of e24hUSE) all increased the risk of hypertension in this highland area.