Hypertension: Etiology (Risk Factors)

00:00 So again the risk factors for high blood pressure: again, a lot of families will have a high baseline blood pressure because of the way that their thermostat is set in the brain; older age with stiffening of the blood vessels increases the blood pressure, causing hypertension; chronic kidney disease of any form is often associated with increased release of renin and hypertension. Even when the kidney disease is not due to arterial stenosis or blood flow change, even if it’s due to diabetic change or other kidney damages – glomerulosclerosis, damage to the little glomerulus that filters the blood from inflammation for example – glomerulonephritis – all of these are diseases that are not caused by low blood pressure but, when they damage the kidney, the result can be increased release of renin and hypertension.

01:02 Diabetes is very commonly associated with kidney disease and certainly associated with hypertension. You see again, left ventricular hypertrophy is often seen in people who have had long-standing hypertension. In the United States, African Americans are particularly prone to hypertension. And it’s a particularly nasty disease in African Americans and also in Africans.

01:26 Females, again, are at higher risk in the elderly population, again partly because they’re the ones that are surviving. But also high blood pressure – high systolic blood pressure – is very common in elderly females often because of marked stiffening of the arterial system with advanced age.

01:48 There are a number of lifestyle factors that contribute to hypertension.

01:52 Number one is obesity. And I need not tell you that obesity is an epidemic in the West these days. And even it’s starting to become epidemic in Asia as well.

02:06 Every increase in weight increases the blood pressure. High intake of salt increases the blood pressure, partly we think because it increases the blood volume. Physical inactivity, failing to exercise regularly increases the risk for hypertension. Ingestion of a low-fibre, high-fat diet increases the risk for hypertension. And heavy alcohol ingestion. So these are all lifestyle factors that contribute to hypertension and often make it difficult to treat the hypertension if these lifestyle factors continue despite medication.