When hyperlipidemia is confirmed on at least two separate occasions, secondary causes should be diagnosed or excluded by taking a detailed medical and drug history, measuring serum creatinine and fasting glucose levels, and testing thyroid and liver function. Causes of secondary dyslipidemia include diabetes, hypothyroidism, obstructive liver disease, chronic renal failure, and use of medications such as progestins, anabolic steroids, and corticosteroids. Therapeutic lifestyle changes should be initiated in all patients to reduce their risk of coronary heart disease: 1.
Reduced intakes of saturated fats (<7% of total calories) and cholesterol (<200 mg per day) 2.
Therapeutic options for enhancing LDL lowering, such as plant stanols/sterols (2 g per day) and increased viscous (soluble) fiber (10–25 g per day) 3.
4.
LDL ≥190 mg/dL Drug therapy Lifestyle LDL >100 mg/dL CHD or CHD risk equivalents Lifestyle Check total cholesterol, HDL, LDL and triglycerides in 5 years changes Drug therapy Drug therapy Lifestyle changes CHD or CHD risk equivalents? No Yes no CHD or CHD risk factors and no changes 0–1 Risk factor and equivalents* 2 or more risk CHD or CHD risk equivalents LDL ≥160 mg/dL LDL ≥130 mg/dL No
Figure 9.4 Treatment decisions based on the LDL cholesterol. LDL, low-density lipoprotein; HDL, high-density lipoprotein. *Coronary heart disease (CHD) risk equivalents: Diabetes or other forms of atherosclerotic disease like peripheral arterial disease, abdominal aortic aneurysm, and symptomatic carotid artery disease. (Adapted from The 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] Expert Panel on the Detection, Evaluation, and Treatment of High Blood Cholesterol in Adults. JAMA 2001;285:2486–2497.)
Figure 9.4 is a suggested algorithm for cholesterol control based on LDL levels. Cholesterol fat-lowering diet books abound in most bookstores and allow the patient to choose a diet she will best follow. The role of exercise and cigarette cessation should be stressed to all patients. Patients with a family history of cardiovascular disease (history of premature coronary artery problems and strokes) should be tested and started on conservative programs in their 20s. After 3 to 6 months, if the LDL remains above 160 mg/dL with zero to one risk factor or above 130 mg/dL with two or more risk factors, then medical therapy should be initiated. Any woman with coronary heart disease or equivalents such as diabetes or other forms of atherosclerotic disease (peripheral arterial disease, abdominal aortic aneurysm, and symptomatic carotid artery disease) should initiate lifestyle changes if her LDL is 100 mg/dL or more and drug therapy if her LDL is 130 mg/dL or more. Anyone with an LDL 190 mg/dL or higher should be considered for drug therapy (33).