Association of anxiety with resistance vessel dysfunction in human atherosclerosis.

OBJECTIVE: Anxiety predicts cardiovascular events, although the mechanism remains unclear. We hypothesized that anxiety symptoms will correlate with impaired resistance and conduit vessel function in participants aged 55 to 90 years.
METHODS: Anxiety symptoms were measured with the Symptom Checklist-90--Revised in 89 participants with clinically diagnosed atherosclerotic cardiovascular disease and 54 healthy control participants. Vascular function in conduit arteries was measured using flow-mediated dilatation, and vascular function in forearm resistance vessels (FRVs) was measured using intra-arterial drug administration and plethysmography.
RESULTS: Anxiety symptoms were not associated with flow-mediated dilatation in either group. Participants with atherosclerosis exhibited significant inverse associations of anxiety symptoms with FRV dilatation (acetylcholine: β = -.302, p = .004). Adjustment for medication, risk factors, and depression symptoms did not alter the association between anxiety and FRV dysfunction, except for body mass index (BMI; anxiety: β = -.175, p = .060; BMI: β = -.494, p < .001). Although BMI was more strongly associated with FRV function than anxiety, combined BMI and anxiety accounted for greater variance in FRV function than either separately. Control participants showed no association of anxiety with FRV function.
CONCLUSIONS: Anxiety is uniquely and substantially related to poorer resistance vessel function (both endothelial and vascular smooth muscle functions) in individuals with atherosclerosis. These relationships are independent of medication, depression, and cardiovascular risk factors, with the exception of BMI. These findings support the concept that anxiety potentially increases vascular events through worsening of vascular function in atherosclerotic disease.