Cardiovascular disease

WHO/ISH Hypertension guidelines

Hypertension is already a highly prevalent cardiovascular risk factor worldwide because of increasing longevity and prevalence of contributing factors such as obesity. Whereas the treatment of hypertension has been shown to prevent cardiovascular diseases and to extend and enhance life, hypertension remains inadequately managed everywhere.

Multiple guidelines for the more effective management of hypertension have been published. Guidelines, to be useful in clinical practice, must be evidence-based and up-to-date. The 1999 WHO/ISH guidelines for the management of hypertension were updated both to respond to some specific concerns and to address a number of issues for which considerable new evidence has been obtained from epidemiological surveys and therapeutic trials.

As to concerns about the 1999 guidelines, one relates to their possible lack of applicability to less developed societies with limited resources since WHO guidelines should be directed towards a global audience.

A second concern relates to their strong advocacy of more intensive blood pressure lowering with the implication of the need for more pharmacological (drug) therapy with intimations that financial support to the committee from pharmaceutical marketers may have influenced this advocacy.

A third concern addresses the lack of documentation of the evidence base for the 1999 guidelines. And lastly, concerns that expert committees may not reflect the needs of practitioners and patients.

Four policies were used to strengthen the scientific validity and credibility of the 2003 update: 1) an explicit evidence based process was used for the development of evidence based recommendations; 2) the expert group was composed of general practitioners, a physician who has worked with consumer groups, a nurse practitioner and specialists to ensure that the recommendations are fully compatible with usual clinical practice; 3) all potential conflicts of interest were fully disclosed; and 4) all expenses incurred in the preparation of the guidelines were paid by the WHO alone.

This revision specifically, addresses the following issues: 1) the ascertainment of global cardiovascular risk to establish both the thresholds for initiation of treatment and the goals of treatment for hypertensives overall and for various subgroups; 2) the appropriate treatment strategies for both non-drug and drug therapies; and 3) the costs of evaluation and treatment in order to optimize the application of guidelines in less developed societies with limited resources that must be most effectively utilized.

A summary of this update has been published in the Journal of Hypertension (ref: J Hypertens. 2003 Nov; 21(11):1983-1992). The detailed update (including evidence tables) is being incorporated into an integrated guideline for assessment and management of cardiovascular risk and is due to be published by end of 2005.