Increased Hair Cortisol Concentrations in Patients With Progressive Keratoconus

To investigate hair cortisol concentration (HCC), a biochemical correlate of chronic psychological stress, and its relationship to the progression of keratoconus.

Eighty-six participants were included in this prospective observational study (32 patients with progressive keratoconus, 32 patients with stable keratoconus, and 22 healthy controls). Hair cortisol concentrations were determined from 3-cm hair strands collected near the scalp from patients and controls as an index of cumulative cortisol secretion during the 3-month period prior to hair sampling. In addition, self-reported chronic stress was assessed using the Trier Inventory for the Assessment of Chronic Stress screening scale.

Patients with progressive keratoconus exhibited higher hair cortisol concentrations (mean value: 29.11 pg/mg; 95% confidence interval [CI]: 22.13 to 38.28) than patients with stable keratoconus (mean value: 15.88 pg/mg; 95% CI: 12.25 to 20.65; P = .007) and healthy controls (mean value: 16.98 pg/mg; 95% CI: 12.30 to 23.44; P = .049). There were no significant differences in hair cortisol concentrations between healthy controls and patients with stable keratoconus (P = .991). Group differences were not affected by relevant covariates (body mass index, age, or sex).

This study shows that increased hair cortisol concentration seems to be associated with the progression of keratoconus. There are a variety of causes of increased hair cortisol concentration. [J Refract Surg. 2017;33(6):383-388.].