Serum long-chain omega-3 polyunsaturated fatty acids and future blood pressure in an ageing population

To investigate the associations of serum long-chain omega-3 polyunsaturated fatty acids (PUFA) and hair mercury with future blood pressure in an ageing population. Prospective study with baseline measurements in 1998-2001 and follow-up measurements in 2005-2008. The linear relationships (beta) of baseline serum fatty acids and hair mercury with future systolic and diastolic blood pressure and pulse pressure were analyzed with multiple linear regression models, using log-transformed values. 181 men and 200 women aged 53-73 y from the Kuopio Ischemic Heart Disease Risk Factor Study (KIHD) population in Eastern Finland, who were free of cardiovascular disease, diabetes or hypertension at baseline. Total serum esterified and nonesterified fatty acids and pubic hair mercury were used as markers for exposure. Anthropometric and other lifestyle and health-related data were collected. The mean serum concentrations were 1.67% (SD 0.92) for eicosapentaenoic acid (EPA), 0.79% (SD 0.16) for docosapentaenoic acid (DPA) and 2.78 (SD 0.92) for docosahexaenoic acid (DHA), of all serum fatty acids. The mean hair mercury concentration was 1.5 mu g/g (SD 1.6). We did not find statistically significant associations between the baseline serum long-chain omega-3 PUFA concentrations or hair mercury content and future blood pressure. Hair mercury did not modify the associations with the long-chain omega-3 PUFAs, either. Higher serum long-chain omega-3 PUFA concentration, a biomarker of fish or fish oil consumption, may not have an impact on future blood pressure in an ageing population.