Effect of systemic hypertension on retinal layers in patients without retinopathy.

Objective: Retinal neuronal damage can be recorded as thinning of inner layers of retina using optical coherence tomography (OCT). This study aimed to determine the effect of systemic hypertension (HTN) on the inner retinal layers in patients without clinically evident hypertensive retinopathy.

Methodology: This cross-sectional observational study used spectral domain OCT to measure the thickness of the peripapillary and macular retinal nerve fibre layer (pRNFL and mRNFL) thickness as well as macular ganglion cell-inner plexiform layer (mGC-IPL) thickness in HTN patients without retinopathy. These measurements were compared with age-matched and sex-matched controls.

Results: Fifty HTN patients without retinopathy and 50 age-sex matched controls ( p  > 0.05) were included in the study. The pRNFL, mRNFL and mGC-IPL thickness in HTN group were 98.9 ± 6.29, 34.62 ± 3.98 and 63.57 ± 4.61 μm, respectively. This was significantly reduced when compared to controls [113.04 ± 6.94 μm ( p  = 0.001); 36.50 ± 5.26 μm ( p  = 0.047); 68.04 ± 4.60 μm ( p  = 0.001) respectively]. A significant reduction in pRNFL ( p  = 0.003) and mGC-IPL ( p  = 0.007) was noted with increased duration of HTN. Sex, family history of HTN, Type of anti-HTN medication did not seem to affect the inner retinal thickness in our study ( p  > 0.05).

Conclusion: Hypertensive patients without retinopathy showed significant thinning of the pRNFL, mRNFL and mGC-IPL when compared to the controls. Longer duration of hypertension was associated with greater thinning of inner retinal layers.