EFFECT OF PSYCHOSOCIAL STRESS AND AGE ON PLASMA NOREPINEPHRINE LEVELS - A REVIEW

Forearm venous plasma norepinephrine and muscle sympathetic nerve activity, which are closely correlated, both increase with age. Recent studies have shown that the increase in plasma norepinephrine with aging is confined to long-term cigarette smokers, whereas values in elderly nonsmokers or young smokers were not different from values obtained in young nonsmokers. The mechanism of the increase in plasma norepinephrine in long-term smokers has not been clarified, but cardiac output and plasma volume were not different in smokers and nonsmokers. In patients who have or have had a duodenal ulcer, the increase in plasma norepinephrine with age is markedly increased. These patients tend to die prematurely because of smoking-associated diseases. These patients may select dysfunctional coping strategies like smoking, which may result in organ pathologies and a compensatory increase in plasma norepinephrine. No close correlation has been established between plasma epinephrine and ''ill health.'' High plasma epinephrine levels may have a deleterious effect on the cardiovascular system in elderly subjects during certain conditions. In a population study, however, we found that low resting plasma epinephrine levels were associated with an unfavorable survival rate. We speculate that an inadequate response to psychosocial stress and the choice of dysfunctional coping strategies may be more harmful and cause more ''ill health,'' than hypersecretion of stress hormones like epinephrine and cortisol, which has been the traditional view.