Treatment of hypertension in obesity

Background: Hypertension and obesity are common medical conditions independ ently associated with increased cardiovascular risk. Many large epidemiolog ical studies have demonstrated associations between body mass index and blo od pressure, and there is evidence to suggest, that obesity is a causal fac tor in the development of hypertension in obese subjects. Weight Reduction and maintenance is an essential first step in the treatmen t of obesity-associated hypertension. Weight reduction may be achieved by b ehavior modification, diet, and exercise or by the use of anti-obesity medi cation. However, the long-term outcomes of weight management programs for o besity are generally poor, and most hypertensive patients will require anti hypertensive drug therapy Pathophysiology: Obese hypertensive patients often have metabolic abnormali ties known to be exacerbated by commonly used antihypertensive agents but a Iso obesity per se is often associated with endorgan damage including left ventricular hypertrophy, glomerular hyperfiltration and microalbuminuria, congestive heart failure or sudden cardiac death. Furthermore they have rev ealed volume expansion, increased cardiac output, and lower total periphera l resistance than lean patients. Hypertension in obese patients appears to be related to both increased sympathetic nervous system activity a nd activ ation of the renin-angiotensin systems. Where antihypertensive therapy is necessary, the aim should be to use agent s based on the hemodynamic and metabolic background and that have benefits beyond blood pressure lowering and improve the conditions most commonly lin ked with obesity-associated hypertension, such as hyperlipidaemia, Type II diabetes, left ventricular hypertrophy, coronary artery disease, or congest ive heart failure. Pharmacotherapy: Based on their favorable metabolic profiles, it would appe ar that ACE inhibitors, angiotensin receptor blockers, calcium channel bloc kers, moxonidine and alpha-blockers can lower blood pressure without worsen ing the metabolic abnormalities, that is just one aspect of the problem. Ye t, most guidelines fail to provide specific advice on the pharmacological m anagement of hypertension in obese patients. This may be due to the fact th at there are currently no studies that have addressed the efficacy of speci fic antihypertensive agents in reducing mortality in obese-hypertensive pat ients. Th is pa per reviews the theoretical reasons for the differential us e of the major classes of antihypertensive agents in the pharmacological ma nagement of obesity-related hypertension and also considers the potential r ole of anti-obesity agents.