High attitudes may produce hypoxemia through

The left ventricle is responsible for pumping oxygenated blood out of the heart and into systemic circulation, which requires generating enough pressure to overcome the resistance of the systemic blood vessels. Therefore, the left ventricle has thicker and more muscular walls than the right ventricle and can generate higher pressures during contraction. In contrast, the right ventricle pumps deoxygenated blood to the lungs, which have lower resistance compared to the systemic circulation, and therefore do not need to generate as high pressures.

Primary hypertension, also known as essential hypertension, refers to high blood pressure that has no identifiable underlying cause. Risk factors for developing primary hypertension include a family history of hypertension, age, obesity, smoking, sedentary lifestyle, stress, and certain dietary factors.

Specifically, diabetes mellitus is a risk factor for hypertension due to the effects of insulin resistance and hyperinsulinemia on the blood vessels, as well as the increased prevalence of obesity and other comorbidities. Moderate alcohol consumption (up to 1 drink per day for women and up to 2 drinks per day for men) may actually have a protective effect against hypertension, but excessive alcohol intake can raise blood pressure and contribute to the development of hypertension.

Asian race is not a significant risk factor for primary hypertension, although there may be differences in the prevalence and severity of hypertension among different racial and ethnic groups.