Hair cortisol concentration (HCC) may be an accurate biomarker of chronic stress in patients with retinitis pigmentosa (RP), according to a study published in Experimental Eye Research.

Researchers conducted an observational study at a single center between 2019 and 2021 consisting of patients with RP (n=78, mean age 51.59±13.40 years) and healthy controls (n=148, 41.29±5.14 years). The team collected 3 cm hair strands from all participants near the scalp and evaluated stress levels using the State-Trait Anxiety Inventory (STAI) questionnaire.

Among the RP cohort, 67% had severe RP, average disease duration was 25.4 (range, 2-50) years, and 74.35% had severe grade anxiety.


Continue Reading

Stratified by severe (n=52) and mild to moderate (n=26) RP status, severe disease was associated with poorer visual acuity (P =.001), more optic disc atrophy (P =.023) and bone spicules (P =.001), lower perimetry (P =.001), and thinner outer retinal thickness at the fovea (P =.001).

Researchers noted higher HCC levels among the RP cohort compared with controls (500.04±120.99 pg/mg vs 136.17±60.51 pg/mg; P <.001). Disease severity correlated with higher levels of HCC with a difference of 274.27 pg/mg measured between patients with severe RP and those classified as mild-moderate (P <.001). However, they observed no such association between self-reported anxiety levels and RP severity. 

“HCC as a clinical measure for long term cortisol exposure in patients with RP are elevated when compared to controls,” according to the investigators, who state that HCC has the potential to be a “promising tool to identify RP patients at risk of vision loss.”

This study was limited by a small sample size, single center design, underrepresentation of patients with mild RP, and failure to account for potential confounding factors such as hair dye or participant body mass index.

Reference

Mateos-Olivares M, Sobas EM, Puertas-Neyra K, et al. Hair cortisol level as a molecular biomarker in retinitis pigmentosa patients. Exp Eye Res. Published online March 6, 2022. doi:10.1016/j.exer.2022.109019