Improving compliance and increasing control of hypertension: needs of special hypertensive populations. Approximately 60 million people in the United States have hypertension. More than half are either untreated or treated without blood pressure control, despite the well-known risks of hypertension and the established benefits of treatment. The major reason for inadequate control of hypertension is poor adherence to treatment. Approximately 50% of patients with hypertension fail to keep follow-up appointments, and only 60% take their medications as prescribed. Barriers to effective therapeutic adherence include poor doctor-patient communication, cost of antihypertensive therapy, and side effects of the drugs. To increase control of hypertension, compliance with therapy must be improved. Physicians and patients must be mutually committed to achieving control of blood pressure. Physicians should communicate instructions clearly and prescribe therapies that are effective, affordable, and have minimal or no adverse effects on patient quality of life or overall cardiac risk profile. The needs of special hypertensive populations (i.e., elderly, black, and young patients) must also be recognized and addressed. Patients must follow recommendations and alert their physicians to any problems with their medications--particularly those relating to side effects and cost. When selecting drug therapy it should be noted that older patients are sensitive to volume depletion and sympathetic inhibition. In this group of patients, initial drug doses should be low and increments smaller and more gradual than in younger patients. Black patients with hypertension show an accentuated response to diuretics and blunted responses to beta-blockers and angiotensin-converting enzyme (ACE) inhibitors as monotherapy. However, when used with a diuretic, there are no racial differences in the blood pressure lowering effects of beta-blockers and ACE inhibitors. 