Hair cortisol concentration in anxiety disorders: exploration of relationships with symptom severity and inflammatory markers.

Background: Hair cortisol concentration (HCC) can be used to periodically assess hypothalamic-pituitary-adrenal (HPA) axis function, and appears correlated with prolonged exposure to stress.

Methods: Serial assessment (at Baseline, Week 6 and Week 12) of participants (n = 35) with anxiety disorders by psychopathological rating scales, with assays of HCC and levels of peripheral anti- and pro-inflammatory cytokines. Patients underwent antidepressant treatment for an initial 6 weeks, followed by cyclo-oxygenase inhibitor-2 (COX-2) inhibitor (celecoxib) augmentation or 'treatment as usual' for a further 6 weeks.

Results: At Baseline (n = 35), HCC was elevated in patients with single-episode but not recurrent-episode anxiety disorders, mean IL-12p70 levels were low, and mean TNF-α levels were elevated. Following 6 weeks of antidepressant treatment (n = 33), mean HCC was within the normal range but mean IL-2 level was low. Celecoxib augmentation (n = 18) was associated with a reduction in anxiety symptoms and normalisation of mean IL-2 levels.

Limitations: Small sample size. Not all participants were assessed at all time points.

Conclusion: Serial assessment of HCC is practicable in patients with anxiety disorders. These preliminary findings warrant further investigation in larger samples.