Plasma levels of natriuretic peptides and year-by-year blood pressure variability: a population-based study
Augmented blood pressure (BP) variability over various time periods has been recognized as a risk factor for cardiovascular diseases. Both atrial and B-type natriuretic peptides (ANP and BNP) are secreted in response to volume or pressure overload to the heart, exerting natriuretic and vasodilator actions. In this study, we examined the relationships between year-by-year BP variability and plasma levels of ANP and BNP in the general population. Study subjects were local residents receiving an annual heath checkup, who had an estimated glomerular filtration rate of > 30 ml min-1 per 1.73 m2 and no history of heart disease. Of those, we selected 314 subjects that received checkups at least five times over the past 6 years. BP variability year-by-year was retrospectively evaluated by s.d., coefficient of variation, average real variability and variation independent of the mean of BP values of 6 or 7 time points. The four parameters of BP variability were each found to significantly correlate with logarithmically transformed ANP and BNP levels by simple regression. When classified by quartiles of s.d. of systolic BP, the highest quartile group showed significantly higher levels of the natriuretic peptides compared with other groups. Multivariate analyses revealed that BP variability was an independent determinant for the ANP and BNP levels. In conclusion, augmented year-by-year BP variability over the past 6 years was associated with elevation of plasma levels of ANP and BNP, suggesting a possible relationship between the BP variability and cardiac load, in the general population.