This trial is designed to:
1. Assess the response to montherapy with : a thiazide diuretic (HCTZ), a calcium-channel
blocker (CCB, amlodipine) and an angiotensin-receptor blocker (telmisartan), among
hypertensive subjects who live at sea level, at medium altitude above sea level and at
high altitude above sea level.
2. To test whether diferentes exist in the response to therapy among subjects who live at
different altitude above sea level
3. To assess the hemodynamic characteristics of hypertension in populations that live at
sea level, at medium altitude above sea level, and at high altitude above sea level.