Obesity in hypertension: effects on prognosis and treatment

OBESITY AND RISK OF MORBIDITY: Obesity is becoming an increasingly important factor in the pathogenesis of hypertension, dyslipidemia and diabetes, which together with hyperinsulinemia comprise the deadly quartet of the insulin resistance syndrome. Obesity in the absence of these other factors is only a minor risk factor, but most obesity is accompanied by one or more of these, worsening the prognosis. The presence of obesity complicates the management of hypertension, probably in large part because of the concomitant insulin resistance which adds to the pathogenetic mechanisms and subtracts from the therapeutic efficacy of many antihypertensive regimens. Unfortunately, some of the agents used to reduce obesity may further aggravate the problem through their stimulation of sympathetic nervous activity. Nonetheless, in the treatment of hypertension in most obese patients who have relatively little excess risk, attempts to reduce body weight should be attempted first, through sensible dietary restrictions, increased aerobic exercise and judicious use of non-hypertensinogenic appetite suppressants. Thereby, additional motivation to lose weight may be provided by the potential of escaping or at least delaying antihypertensive drug therapy. TREATMENT OF HIGHER-RISK OBESE INDIVIDUALS: Those obese hypertensive individuals at greater risk should be immediately started on antihypertensive drug therapy along with attempts to reduce the obesity. The choice of initial and subsequent therapy should take the patient's individual needs into account. For those with dyslipidemia or diabetes, diuretics and beta-blockers should be avoided unless there are specific indications for their use (e.g. reactive sodium retention or postmyocardial infarction). In such patients, an alpha-blocker, an angiotensin converting enzyme inhibitor or a calcium antagonist may be more appropriate. If the first drug is not sufficient, combination therapy should be considered. A diuretic may be needed to overcome reactive sodium retention. Because most obese hypertensive individuals will not be able to lose much weight, effective antihypertensive drug therapy will usually be indicated.