CLINICAL AND MOLECULAR BIOMARKERS IN THE MANAGEMENT OF GLAUCOMA SMOKERS

Abstract

Purpose : Smoking is a health problem worldwide. Being the optic nerve especially vulnerable to tobacco abuse, we intend to identify clinical and molecular biomarkers and to evaluate its usefulness to provide objective metrics for glaucoma patient care in smokers.

Methods : A transversal prospective study was carried out in 195 participants (both sexes), classified as: POAG patients (n=78) and healthy controls (CG; n=117), subdivided according to tobacco habit [smokers (+S), ex-smokers (ex), non-smokers (-S)]. Interview, systematized ophthalmic examination [including papillary optic coherence tomography, (OCT)], exhaled air CO-oximetry to non-invasive determining carboxyhemoglobin saturation (SpCO), and blood collecting samples to perform pro-oxidant (malondialdehyde -MDA-) and antioxidant (TAC) status, were done. Data were statistically processed by the SPSS 24.0 program.

Results : Mean age was 57 ± 9 years. Gender distribution was 73% man/37% woman in the POAG patients and 52% man/48% woman in the CG. The POAG+S showed significantly lower retinal nerve fiber layer (RNFL) thickness versus the ex and –S groups (p<0,001), and the CG (p<0,001). Negative correlations were found between both the amount of cigarettes/day (mean 20 ± 6) and habit duration, regarding the RNFL thickness (p=0,000). Mean SpCO (ppm) in POAG+S was 5,4 ± 2.1 versus 2,3 ± 1,1 in the CG+S (p<0,05). Significantly higher MDA and lower TAC in plasma were found in the POAG+S respect to the ex (p<0,05) and –S (p<0,05), and the CG (p<0,001).

Conclusions : The optic fiber loss in glaucoma smokers can be monitoring by OCT screenings. The higher oxidative stress that the glaucoma smokers have strongly suggests an extreme susceptibility to vascular and neural damage. We confirm the effectiveness of dynamic CO-oximetry in the office to measure the tobacco exposure/severity in POAG. We propose new clinical and molecular biomarkers to provide actionable information to help identify which smoking patients may be at higher risk of glaucoma progression.

This is a 2020 ARVO Annual Meeting abstract.