The 2001 Canadian Hypertension Recommendations: What’s New and What’s Not So New but Is Still Important

Abstract

INTRODUCTION

Hypertension is one of the most common reasons for an adult patient to visit a physician and is estimated to be the third leading risk associated with death worldwide.1 The most recent reliable data on hypertension prevalence and control in Canada are 10 to 15 years old.2 At that time 22% of adult Canadians had high blood pressure and only 16% of those with hypertension were treated and controlled. Preliminary data (N.R.C. Campbell, unpublished data) suggest a significant increase in prescriptions of major classes of antihypertensive agents coinciding with the introduction of the annual recommendations and implementation process; however, whether this trend reflects an improvement in treatment and control of hypertension is uncertain. Unfortunately, our national health surveillance is inadequate to determine whether hypertension prevalence, awareness, treatment, or control has changed. Given the data that are available, it behooves all health care professionals to prioritize hypertension as a public health issue and to aggressively identify, treat, and control hypertensive patients according to the best available evidence and recommendations. This is the third year that the Canadian Hypertension Recommendations Working Group has comprehensively updated its hypertension recommendations. 3-5 The recommendations are linked to an expanding implementation effort.6 The current report is a brief summary of the 2001 recommendations, highlighting those that are new, revised, or simply important to improve blood pressure control in Canada. New recommendations of specific interest include an updated section on management of hypertension in people with diabetes, especially new recommendations for initial therapy, and a new recommendation to lower blood pressure following the acute phase of stroke or transient ischemic attack. The arbitrary classification of elderly people as those age 60 or older has been removed. Evidence for an age effect is required, as opposed to the previous requirement for evidence in specific age categories. This has resulted in a more aggressive threshold for initiating therapy in those over age 60. The recommendation to switch first-line therapies when there is inadequate response has been changed to a recommendation to combine first-line therapies, in recognition of the need for multiple drugs to control hypertension as well as the sequential method of adding medications used in major therapeutic trials. There are also new comprehensive sections on management of patients with pheochromocytoma and hyperaldosteronism. The purpose of this summary is to provide a rapid update to the 2000 hypertension recommendations.4,5 A full publication of the comprehensive recommendations will be published separately. The latter publication is intended to be a scientific reference and not a clinical practice guideline. A slide kit and clinical practice algorithms supporting the full 2001 recommendations will be available to download at the Web site of the Canadian Hypertension Society (www.chs.md). The methods for producing the recommendations have been published previously,7 but there have been some revisions. In 2001 a separate meeting of those involved in the production of recommendations was held to discuss new, changed, or controversial recommendations and evidence. A voting process adopted in 2000 to exclude recommendations with which 30% or more of those involved on the subgroups, central review committee, and steering committee disagreed was continued, but individuals with a direct conflict of interest on specific recommendations were excluded from voting on those recommendations. Those with conflict of interest participated in the discussions following disclosure. The recommendations were based on the results of literature searches (to at least March 2001), personal knowledge of published literature, contact with authors, and major clinical trials published prior to November 2001.