Objectives: The sympathetic nervous system is implicated in the development and maintenance of hypertension. However, the predictive impact of arterial plasma catecholamines has never been reported. We investigated arterial catecholamines and blood pressures (BPs) prospectively over 20 years in a group of well-characterized middle-aged men.
Methods: Fifty-six of original 79 men were available for the follow-up. Multiple regression analysis was done with mean BP at follow-up as a dependent variable, and arterial plasma catecholamines and BP at baseline as independent variables.
Results: Half of the originally normotensive men developed hypertension during follow-up. There were significant differences in the screening BP values measured at baseline between the new hypertensives and the sustained normotensives. Multiple regression analysis revealed arterial adrenaline at baseline as an independent predictor of mean BP at follow-up in the new hypertensives (beta = 0.646, R2 = 0.42, p = 0.007). Furthermore, arterial noradrenaline at baseline was a negative independent predictor of mean BP at follow-up in the sustained normotensives (beta = -0.578, R2 = 0.334, p = 0.020). Noradrenaline increased with age in the group as a whole (1318+/-373 vs 1534+/-505 pmol/l, p = 0.010) while adrenaline did not change.
Conclusion: Our data suggest that arterial adrenaline is involved in the development of hypertension over 20 years in middle-aged men. Men with sustained normotension may have an inherent protection against sympathetic overactivity. Furthermore, screening BP at baseline in normotensive men differentiated between those who developed hypertension and those who remained normotensive at follow-up.