The management of severe hypertension in Australian general practice

Abstract

Background: Severe hypertension (SHT) (Blood Pressure, BP ≥ 180/110 mmHg) is associated with considerable morbidity and mortality, yet little is known about how it is managed. The purpose of this study is to examine the management of SHT by Australian general practitioners (GPs) and to explore its variance across patient characteristics and clinical practices.

Methods: Review of electronic medical records for a year before and after a recorded measure of SHT in 7,499 patients by 436 GPs in 167 clinics throughout Australia during 2008-2009. Outcome measures included follow-up, referral, changes to antihypertensive drug treatment, and BP control (normotensive reading, BP < 140/90 mmHg, and whether subsequent recorded measures were also in the normal range--sustained normotension).

Results: Of 7,499 patients with an electronic BP record of SHT, 94% were followed up (median time 14 days); 8% were referred to an appropriate specialist (median time 89 days--2% within 7 days) and 86% were managed by GPs. GPs initiated or changed antihypertensive drugs in 5,398 patients (72% of cohort); of these, 46% remained hypertensive (4% with SHT) and 7% achieved sustained normotension; 6% had no further electronic BP records. The remaining 14% had no medication changes; among these, 43% remained hypertensive (5% with SHT) and 3% achieved sustained normotension; 32% had no further electronic BP records. Some outcome measures displayed a variance across GP clinics that was mostly unexplained by patient or practice characteristics.

Conclusions: Most patients with SHT had at least one follow-up visit and 72% had initiation of, or changes to, antihypertensive drug treatment. Although most of the patients experienced some improvement, blood pressure control was poor. Some clinics showed better performance. Suggestions are made for the development of clinical standards to facilitate appropriate management of this dangerous condition.

Figure 1

Summary illustration of the numbers of patients with severe hypertension (SHT) with respect to follow-up, referral, changes in antihypertensive drugs treatment and blood pressure (BP) control during the year of follow-up.

Figure 2

Times to follow-up, referral, a normotensive reading and sustained normotension during the study year. Percentages are calculated with respect to the full cohort of 7,499 patients. Shaded areas correspond to 50% of patients (median time).

Figure 3

Distribution of the percentage of patients with follow-up visits, who had a normotensive reading, and who achieved and sustained normotension by general practice (GP) clinic. Only GP clinics with 20 or more severe hypertension (SHT) patients are included. Percentages are calculated with respect to the full cohort of 7,499 patients. Clinics were sorted from lowest to highest percentage value of follow-up visits.