Metabolic syndrome is a constellation of findings that increases a patient’s risk for cardiovascular disease. A diagnosis of metabolic syndrome is made when three of the criteria shown in Table 12–1 are met. Mrs. Seits’s results meet three of the criteria for metabolic syndrome: hypertriglyceridemia, low high-density lipoprotein (HDL), and impaired fasting glucose. Although this patient’s low-density lipoprotein (LDL) is high, LDL is not a criterion for metabolic syndrome. It is important to remember that weight gain is the biggest risk factor for developing metabolic syndrome. It is estimated that 60% of patients with schizophrenia also have metabolic syndrome. (pp. 161–163, 165)
Three of the following criteria: |
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Abdominal obesity |
Men: waist circumference ≥ 40 in. (102 cm) Women: waist circumference ≥ 35 in. (88 cm) |
Hypertriglyceridemia |
Serum TG ≥ 150 mg/dL |
Low HDL cholesterol |
Men: serum HDL < 40 mg/dL Women: serum HDL < 50 mg/dL |
Elevated blood pressure |
BP ≥ 130/85 mmHg Or medication for HTN |
Impaired fasting glucose |
Fasting BG ≥ 100a Or medication for diabetes |
Note. BG = blood glucose; BP = blood pressure; HDL = high-density lipoprotein; HTN = hypertension; TG = triglycerides. aHemoglobin A1c (HbA1c) ≥ 6.5% is now used for the diagnosis of diabetes. HbA1c ≥ 5.7% has a 91% specificity for impaired fasting glucose (BG ≥ 100 mg/dL) (American Diabetes Association: “Diagnosis and Classification of Diabetes Mellitus.” Diabetes Care 33 (suppl 1):S62–S69, 2010). Source. Adapted from Alberti KG, Zimmet P, Shaw J: “Metabolic Syndrome—A New Worldwide Definition: A Consensus Statement From the International Diabetes Federation. Diabetic Medicine 23:469–480, 2006; Expert Panel on Detection, Evaluation, and Treatment of High Blood Cholesterol in Adults: “Executive Summary of the Third Report of the National Cholesterol Education Program (NCEP) (Adult Treatment Panel III).” JAMA 285:2486–2497, 2001. |
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This patient has dyslipidemia and should be treated with a 3-hydroxy-3-methylglutaryl–coenzyme A (HMG-CoA) reductase inhibitor, or statin. Guidelines for appropriate initiation and choice of statins are based on the presence of cardiovascular risk factors, lipid levels, and age. Because this patient is over age 21 and has an LDL above 190 mg/dL, a statin should be initiated to reduce risk for cardiovascular disease. Although her hemoglobin A1c is above goal, her metformin dose should be increased prior to adding insulin. Because her blood pressure is at goal (< 140/90 mmHg) and she is already taking an angiotensin-converting enzyme inhibitor (ACE) inhibitor, an angiotensin II receptor blocker (ARB) such as losartan need not be added. Weight loss may be improved with optimization of metformin dose, which would be more appropriate than starting topiramate. (pp. 166, 168, 172)
Patients taking second-generation antipsychotics (SGAs) should be evaluated and screened for metabolic syndrome. Prior to starting an SGA, providers should check baseline BMI, waist circumference, blood pressure, fasting glucose, and a fasting lipid panel. A personal/family history should also be established. BMI should be monitored at weeks 4, 8, 12, and then quarterly. If BMI is stable, it can then be followed annually. Blood pressure, lipids, and fasting glucose should be rechecked 12 weeks after an SGA is started. If patient is at goal, blood pressure and glucose can then be monitored annually, whereas lipids should be checked every 5 years. Waist circumference and history should also be monitored annually. (p. 164)
ACE inhibitors and ARBs are first-line treatment in patients with high blood pressure and diabetes. Stage I hypertension is defined as average systolic blood pressure greater than 139 mmHg or average diastolic blood pressure greater than 89 mmHg occurring at two separate visits after an initial screening. It is important to note that use of an ACE inhibitor (as well as thiazides diuretics and ARBs) can increase lithium levels and increase risk for lithium toxicity. They can also cause hyperkalemia; therefore, a basic metabolic panel should be checked prior to initiating an ACE inhibitor, and rechecked shortly after starting or adjusting dosage. Patients should be informed that cough is the most common side effect of an ACE inhibitor, often requiring a substitution for the ACE inhibitor by an ARB, which has a low incidence of cough but similar benefits for blood pressure and kidney disease. (pp. 169, 173–175)
Switching to a medication with lower risk for obesity is a first-line intervention in patients who develop metabolic syndrome. In general, first-generation antipsychotics have fewer metabolic side effects than SGAs. Ideally, all patients with metabolic syndrome should be referred to a primary care physician (PCP) for intensive management. A nutritionist can help tailor diet to help treat the dyslipidemia, hyperglycemia, obesity, and hypertension. (pp. 172–176)
Each component of this patient’s metabolic syndrome should be addressed and treated. Lisinopril is appropriate to initiate for better blood pressure control, whereas metformin can help control blood glucose levels and limit additional weight gain. Although Mrs. Heater does have dyslipidemia and should begin taking a statin, simvastatin 40 mg is a more appropriate starting dose. Higher dosages of statins are associated with more side effects, including myalgias and abdominal pain. If lipids are still not at goal after she has taken simvastatin 40 mg/day for 3 months, the patient should be switched to a more potent statin, such as rosuvastatin or atorvastatin. (pp. 168, 172–173)
This patient’s metabolic syndrome is still poorly controlled despite the interventions you have made, and will likely need more aggressive management. Therefore, Mrs. Heater needs to establish with a PCP as soon as possible. Absolute indications for referral to a PCP in this patient include blood glucose above 200 mg/dL despite treatment, and persistent blood pressure above 180/110 mmHg despite treatment. It is unlikely that a small dosage adjustment in her lisinopril will get her blood pressure to goal. Waist circumference should be checked annually in patients taking SGAs, not after just 1 month. A lipid panel should be checked 3 months after initiating therapy, not after 1 month. (pp. 164, 174–175)
Mrs. Heater is doing much better, and her blood pressure and diabetes are now well controlled on her new medication regimen. She is tolerating the simvastatin, and her lipid panel is at goal. She is having symptoms of obstructive sleep apnea, which can be a common complication of obesity and the metabolic syndrome. A diagnostic sleep study is the best test to evaluate for this concern. (pp. 172–174)