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 hypothalamo-pituitary-adrenal 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 six weeks, followed by COX-2 inhibitor (celecoxib) augmentation or 'treatment as usual' for a further six 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 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 hair cortisol concentration is practicable in patients with anxiety disorders. These preliminary findings warrant further investigation in larger samples.