Patterns of antihypertensive drug utilization in primary care

In the treatment of hypertension, physicians' attitudes and practice patterns are receiving increased attention as contributors to poor blood pressure (BP) control. Thus, current use of antihypertensive drugs in primary care was analyzed and the association with selected physician and patient characteristics was assessed.

The Hypertension and Diabetes Risk Screening and Awareness (HYDRA) study is a cross-sectional point prevalence study of 45,125 primary care attendees recruited from a representative nationwide sample of 1912 primary care practices in Germany. Prescription frequencies of the various antihypertensive drugs in the individual patients were recorded by the physicians using standardized questionnaires. We assessed the association of patient variables [age, gender; co-morbidities such as diabetes, nephropathy or coronary heart disease (CHD)] and physician variables (general practitioner vs internist, guideline adherence, etc.) with drug treatment intensity and prescription patterns.

Of all 43,549 patients for whom a physician diagnosis on hypertension or diabetes was available, 17,485 (40.1%) had hypertension. Of these hypertensive patients, 1647 (9.4%) received no treatment at all, 1191 (6.8%) received non-pharmacological measures only, and 14,647 (83.8%) were given one or more antihypertensive drugs. Drug treatment rates were lower in young patients (16-40 years: 57.4%). BP control was poor: 70.6% of all patients were not normalized, i.e., had BP >/=140/90 mmHg. Antihypertensive treatment was generally intensified with increasing age, or if complications or comorbidities were present. The use of the different drug classes was rather uniform across the various patient subgroups (e.g., by age and gender). Individualized treatment with regard to co-morbidities as recommended in guidelines was not the rule. Adherence to guidelines as self-reported by physicians as well as other physician characteristics (region, training etc.) did not result in more differentiated prescription pattern.

Despite the broad armamentarium of drug treatment options, physicians in primary care did not treat hypertension aggressively enough. Treatment was only intensified at a late stage, after complications had occurred. Treatment should be more differentiated in terms of coexisting morbidities such as diabetes, nephropathy, or CHD.