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

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.

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.

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

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