Primary prevention of cardiovascular diseases in primary care: prove principles and persistent practice

Prevention of cardiovascular diseases in clinical practice includes identification of persons at high risk, assessing the well known risk factors, proper estimation and optimal communication of CVD risk and appropriate allocation of therapies, all with the aim to ultimately improve outcomes for patients. In many countries, including the Netherlands, primary care physicians play a crucial role in this multi-factorial approach, since they have repeated contact and long-term relationships with the majority of the population, know their lifestyle, know about illnesses of a patient’s relatives, register risk factor measurements and have practice nurses carry out chronic disease management programs under their supervision. This make general practitioners particularly capable to accomplish preventive tasks as spelled out in current cardiovascular risk management guidelines. The question of how prevention is actually carried out in primary care needs to be addressed, as is done in the present thesis. The present Dutch cardiovascular risk management guideline included in this thesis gives general practitioners directions to identify, advice and treat high risk patients they may encounter in daily practice. In this guideline, risk charts are included to estimate risk of cardiovascular diseases, based on an individual’s age, sex, smoking habit, blood pressure and cholesterol level. In this thesis, the adapted European SCORE risk prediction model for cardiovascular diseases used in the guideline was compared to the former used Framingham prediction model. Both have a good discriminative ability (ranking persons in order of risks) and the SCORE is slightly better in predicting absolute risks. Furthermore we concluded in this thesis that the risk model of the guideline is regularly used to estimate absolute risk of individual patients in many cardiovascular risk management consultations in primary care, but the model is used to a lesser extent to explain risk to patients. In the studies in the thesis, we showed that an ECG in hypertensive patients often detects abnormalities important for daily for clinical practice. According to the guideline, patients at high risk for cardiovascular diseases should be advised to improve their lifestyle and, depending of the level of risk, they should receive anti-hypertensive and lipid lowering therapy. However, in this thesis we found that these directions were not yet sufficiently incorporated into routine clinical practice as hypertensive persons, who are aware of this condition, had almost similar lifestyles compared to persons not aware of their hypertension. Furthermore, we showed that only two third of the hypertensive persons who are also at high risk, were treated with appropriate drug therapy and only 16% of those with increased cholesterol level and also at high risk are treated with drug therapy as recommended in the guideline. Thus, major opportunities for cardiovascular prevention are being missed. The evidence for effectiveness of risk reduction strategies is overwhelming but current cardiovascular prevention could dramatically be improved by better implementation of the available knowledge. Different means to enhance implementation could be: improvement of risk factor registration, explaining risk to patients when applicable, involvement of non-physicians and assuring adequate financial support while restricting the workload