Objective: Depression is a risk factor for morbidity and mortality in a variety of populations, and anxiety has also been associated with risk of mortality among cardiac patients. Dysfunction of the autonomic nervous system may be involved in this risk. The primary goal of this study was to evaluate the relationship between levels of self-reported symptoms of depression and anxiety and 24-hour urinary catecholamine excretion.
Method: Ninety-one women aged 47-55 years were evaluated. Depression symptoms were assessed with the Beck Depression Inventory (BDI) and state anxiety was assessed with the state anxiety portion (SAI) of the Spielberger State-Trait Anxiety Inventory (STAI). Twenty-four hour urine collections were assayed for epinephrine (EPI), norepinephrine (NE) and cortisol (CORT). EPI, NE and CORT were indexed by body surface area to control for individual differences in body size.
Results: Higher levels of depression symptoms were associated with increased 24-hour NE excretion (r=.27, P=.009), with depressed women (n=17, BDI scores >/=10) exhibiting an approximately 25% higher rate of urinary NE excretion than women with BDI scores <10 (n=74), P=.007. Higher levels of state anxiety were also related to greater NE excretion (r=.28, P=.01), and CORT excretion was related to both depression (r=.23, P=.02) and anxiety (r=.22, P=.04). Depression and anxiety symptoms were unrelated to urinary EPI excretion.
Conclusions: The current findings that higher levels of depression and anxiety symptoms are related to increased 24-hour urinary NE and CORT excretion among women suggests that depression and anxiety may be associated with increased sympathetic nervous system (SNS) activity, and are consistent with the possibility that SNS activity may play a role in the increased mortality associated with depression in community-dwelling older adults.