Ethnic differences in blood pressure: Findings from the Fletcher Challenge-Auckland University Heart and Health Study

Aims. To investigate the determinants of ethnic differences in blood pressure, hypertension and the prevalence of additional risk factors for cardiovascular disease among a New Zealand population. Methods. Baseline data from the Fletcher Challenge-University of Auckland Heart and Health Study were analysed for ethnic differences in blood pressure, and the likelihood of those with hypertension having other major cardiovascular disease risk factors was estimated. Results. Maori and Pacific Islands participants had mean diastolic blood pressure up to 3 mmHg higher than Europeans, but Pacific Islands people had mean systolic blood pressure 3-4 mmHg lower than Europeans and Maori respectively. After adjustment for age and gender almost 20% of Maori, 16% of Pacific Islands and 11% of European people were classified as hypertensive. Adjustment for body mass index and alcohol consumption almost eliminated ethnic differences in blood pressure, and body mass index was found to be the single most important modifiable determinant of raised blood pressure. Greater proportions of Maori (15%) and Pacific Islands people (14%) with hypertension had multiple additional cardiovascular risk factors compared with Europeans (8%), but similar proportions were on antihypertensive drug treatment. Conclusions. Efforts to reduce obesity have the potential to significantly reduce raised blood pressure among Maori and Pacific Islands people. Overall cardiovascular risk is more likely to be higher in Maori and Pacific Islands people than in Europeans with hypertension, indicating that greater proportions of Maori and Pacific Islands people with high blood pressure should be receiving treatment.