Antihypertensive Therapy in Diabetic Patients

Hypertension in diabetic patients is more common than in controls, contributes substantially to their increased cardiovascular morbidity and mortality, and should be treated as accurately as diabetes mellitus itself. After appropriate exclusion of secondary forms, the first therapeutic step consists of reduction of overweight, salt intake, and smoking; the omission of interfering drugs; and adequate instruction. Step 2 has usually been the prescription of a diuretic drug, in spite of its known side effects on carbohydrate and lipid metabolism. A new possible alternative may be a calcium antagonist. Results in 10 hypertensive diabetic persons suggest that at a dose that normalizes blood pressure, neither carbohydrate nor lipid metabolism is altered, uric acid decreases, the exaggerated cardiovascular reactivity toward norepinephrine becomes normal, and the pressor dose for angiotensin II tends to rise. Body weight, blood volume, exchangeable sodium, as well as plasma and urinary sodium, potassium, and creatinine levels were unchanged. The third therapeutic step is the addition of a cardioselective beta blocker in a moderate dose. This avoids the disadvantages of beta 2-adrenergic blockade such as decreased insulin output, prolonged hypoglycemia, diminished glucagon secretion, and increased vasospasticity during hypoglycemic states, as well as aggravation of peripheral vascular disease. Alternatives are other sympatholytics with their known tendency to cause or increase orthostatic and sexual problems or, again, a calcium antagonist. In step 4, a hydralazine-type drug or prazosine is added. The fifth step, which adds minoxidil or captopril to the previous drugs, should only be taken after a specialist reevaluates the overall situation.