CRISTOPH – A cluster-randomised intervention study to optimise the treatment of patients with hypertension in General Practice

Achim Mortsiefer¹ , Tobias Meysen¹ , Martin Schumacher¹ , Claudia Lintges¹ , Maren Stamer² , Norbert Schmacke² , Karl Wegscheider³ , Heinz-Harald Abholz¹ and Jürgen in der Schmitten¹

¹Department of General Practice, University Hospital, P.O. Box 101001, 40225 Düsseldorf, Germany

²Health Systems Research Chair (AKG), University of Bremen, Bibliothekstr. 1, 28359 Bremen, Germany

³Department of Medical Biometry and Epidemiology, University Medical Center Hamburg-Eppendorf, Martinistrasse 52, 20246 Hamburg, Germany

author email corresponding author email

BMC Family Practice 2008, 9:33doi:10.1186/1471-2296-9-33


Published:	10 June 2008

Abstract

Background

Recent guidelines for the management of hypertension focus on treating patients according to their global cardiovascular risk (CVR), rather than strictly keeping blood pressure, or other risk factors, below set limit values. The objective of this study is to compare the effect of a simple versus a complex educational intervention implementing this new concept among General Practitioners (GPs).

Methods/design

A prospective longitudinal cluster-randomised intervention trial with 94 German GPs consecutively enroling 40 patients each with known hypertension. All GPs then received a written manual specifically developed to transfer the global concept of CVR into daily General Practice. After cluster-randomisation, half of the GPs additionally received a clinical outreach visit, with a trained peer discussing with them the concept of global CVR referring to example study patients from the respective GP. Main outcome measure is the improvement of calculated CVR six months after intervention in the subgroup of patients with high CVR (but no history of cardiovascular disease), defined as 10-year-mortality ≥ 5% employing the European SCORE formula. Secondary outcome measures include the intervention's effect on single risk factors, and on prescription rates of drugs targeting CVR. All outcome measures are separately studied in the three subgroups of patients with 1. high CVR (defined as above), 2. low CVR (SCORE < 5%), and 3. a history of cardiovascular disease. The influence of age, sex, social status, and the perceived quality of the respective doctor-patient-relation on the effects will be examined.

Discussion

To our knowledge, no other published intervention study has yet evaluated the impact of educating GPs with the goal to treat patients with hypertension according to their global cardiovascular risk.

Trial registration

ISRCTN44478543