Aspirin is the most appropriate treatment to reduce cardiovascular risk in this patient with metabolic syndrome. According to the International Diabetes Federation and the American Heart Association (AHA), diagnosis of metabolic syndrome is made by the presence of three or more of the following five criteria: (1) increased waist circumference; (2) serum triglyceride level of 150 mg/dL (1.70 mmol/L) or higher (or taking medications for hypertriglyceridemia); (3) HDL cholesterol level lower than 40 mg/dL (1.04 mmol/L) in men and lower than 50 mg/dL (1.30 mmol/L) in women (or taking medication specifically for low HDL cholesterol); (4) blood pressure of 130/85 mm Hg or higher (or taking antihypertensive medications); and (5) fasting plasma glucose level of 100 mg/dL (5.6 mmol/L) or higher (or taking medications for hyperglycemia). The patient meets at least three criteria (elevated triglyceride level, decreased HDL cholesterol level, antihypertensive treatment). Management of patients with metabolic syndrome should focus on optimizing general health and targeting the individual components of the metabolic syndrome. Lifestyle changes include education on the importance of following a heart-healthy diet, implementing a weight loss plan, and exercising for 30 minutes daily at least 5 days per week. Patients with hypertension should be treated aggressively to achieve the blood pressure goals outlined by the Eighth Joint National Committee. Similarly, dyslipidemia should be treated according to American College of Cardiology (ACC) and AHA cholesterol treatment guideline, and hyperglycemia should be managed per guidelines from the American Diabetes Association. Additionally, the AHA recommends low-dose aspirin for patients with metabolic syndrome with a 10-year cardiovascular risk of 10% or higher. This patient's hypertension and hyperlipidemia are being managed; however, he should also be prescribed aspirin based on his increased risk, provided that his risk for bleeding is not increased.

Diltiazem will not provide additional cardiovascular risk reduction in this patient. Moreover, intensification of his hypertension therapy is not indicated, since the blood pressure goal for patients younger than 60 years is a systolic pressure of less than 140 mm Hg and a diastolic pressure of less than 90 mm Hg. The patient's pressures are within this range.

Fenofibrate increases the potential for drug-induced side effects and has uncertain additive cardiovascular risk reduction when used with statins, which are clearly indicated in this patient based on ACC/AHA guidelines. Fibrate therapy is reserved for patients with hyperlipidemia who do not tolerate or do not respond to statin monotherapy, patients who have triglyceride levels higher than 500 mg/dL (5.65 mmol/L), or patients with hypertriglyceridemia-induced pancreatitis.

The role of metformin in the metabolic syndrome has not been clearly defined. It may reduce the incidence of metabolic syndrome in at-risk patients, but healthy lifestyle modifications are equally effective or superior to metformin in reducing cardiovascular risk. Metformin has also not been shown to reduce cardiovascular events in patients without diabetes. Metformin would be a reasonable choice for both treatment of hyperglycemia and improvement of metabolic parameters if this patient did have impaired fasting glucose or impaired glucose tolerance, and it would be the initial drug of choice if the patient develops diabetes.