Background: In the clinical-practice setting, only a small percentage of patients treated with antihypertensive drugs become normotensive. Furthermore, the diversity of drug classes used makes comparison of treatments difficult.
Objective: The goal of this study was to characterize the types and efficacy of antihypertensive treatments used in primary care in the area of Ravenna, Italy. The study was conducted in the context of the PANDORA Project, an open-ended global outcome study.
Methods: Data were gathered from general practitioners (GPs) and were stored by the GPs or through links with national health service databases. The population of interest was patients with essential hypertension taking antihypertensive medication, each of whom was observed for 365 days. Blood pressure was measured in the morning or afternoon using an automated device, in accordance with normal clinical practice. At each office visit, the GP reviewed and made any necessary adjustments to the patient's antihypertensive treatment. Antihypertensive drug use was assessed by calculating the mean daily dose (MDD) of the prescribed drug and the duration of treatment (DT). A DT > or = 273 days constituted continuous therapy, and a DT <273 days constituted discontinuous therapy. Adverse events were not collected.
Results: Twenty-one GPs took part in the study. The study population included 969 patients (443 men, 526 women), all of them white, whose ages ranged from 23 to 88 years. At enrollment, 327 patients were normotensive (blood pressure <140/90 mm Hg) and 642 were hypertensive despite drug treatment. More than 25 treatment regimens were identified. Over the course of follow-up, 49 patients had discontinuous therapy and 920 had continuous therapy. Among those who had continuous therapy, 117 (12.7%) took an MDD of <0.5 tablet/d; 297 (32.3%) took > or = 0.5 and <1 tablet/d; 364 (39.6%) took > or = 1 and <2 tablets/d; and 142 (15.4%) took > or = 2 tablets/d. At the end of the observation period, the proportion of normotensive patients had increased by 5.7% (P < 0.001).
Conclusion: Based on the findings of this study, improper use of antihypertensive drug therapy appears to be one of the reasons for the relatively small proportion of patients who attain blood pressure control with treatment.