Long-term outcome of cardiovascular prevention: a Nijmegen Academic Family Practices Network study

Abstract

Context: Cardiovascular disease is common and preventable. Primary care is the preferred setting for individual prevention and management.

Objective: This study analyzed the long-term outcome of cardiovascular risk in a family practice population.

Design: A longitudinal cohort analysis of cardiovascular outcome after 18 years, in participants of a randomized controlled trial (RCT) of cardiovascular prevention. In 1977, a RCT with cluster randomization at practice level assessed the effects of a 1-year preventive intervention in patients 20 to 50 years of age. Cardiovascular risk factors (smoking, body mass index, blood pressure, serum cholesterol, family history, and physical activity) were measured and intervention was a practice-nurse support for the follow-up of those at elevated risk. The control practices prescribed care as usual. Between 1994 and 1995, all participants were approached again, to analyze subsequent (cardiovascular) mortality and morbidity and their cardiovascular risk in a random sample.

Setting: The Nijmegen Academic Family Practices Network, The Netherlands.

Participants: All participants (7092) of the 1977 screening for follow-up morbidity and mortality, 2600 for re-measurement risk factors.

Outcome measures: Cardiovascular risk factors; cardiovascular morbidity and mortality 1977-1995.

Results: Follow-up was achieved in 5945 participants (84%) and 2335 participated in the re-measurement (89%). No effects of the preventive intervention were found, but those initially at low risk profile were still so 18 years later. Risk of subsequent cardiovascular mortality and morbidity was related to baseline risk, but for women, the absolute risk was low in all risk strata and lower than predicted from international references.

Conclusions: This study demonstrated the feasibility of family practice network research in pursuing longitudinal research. A single cardiovascular screening resulted in reliable risk assessment: those initially at low risk still were so after 18 years. Effects of a 1-year intensive intervention could no longer be demonstrated.