Association of ABO and Rh blood groups with retinal structural indices

Purpose: To determine the association between ABO and Rh blood groups with retinal structural indices including macular thickness and peripapillary retinal nerve fiber layer thickness.

Methods: This cross‐sectional study was conducted using convenience sampling in a tertiary referral eye hospital in Tehran, Iran. Study participants were referred to the hospital laboratory to test their blood group. Ocular examinations were performed including measurement of visual acuity, auto‐refraction, subjective refraction, and slit‐lamp biomicroscopes. Retinal imaging was carried out using Spectral‐domain optical coherence tomography under dilated papillary conditions.

Results: According to the multiple linear regression model, the global retinal nerve fiber layer thickness [coefficient: ‐3.05 (95% confidence interval: ‐5.30 to ‐0.74); p = 0.010] and retinal nerve fiber layer thickness in the superior [coefficient: ‐4.65 (95% confidence interval: ‐8.40 to ‐0.89), p < 0.001] and inferior [coefficient: ‐4.00 (95% confidence interval: ‐7.81 to ‐0.19); p = 0.040] quadrants were significantly thinner in individuals with blood type B compared to those with other ABO blood groups. The average [coefficient: 12.69 (95% confidence interval: 4.12‐21.64); p = 0.004) and central [coefficient: 16.21 (95% confidence interval: 6.44‐25.97); p = 0.001) macular thicknesses were significantly thicker in AB group compared to other blood groups. The average macular thickness was significantly thinner in Rh+ compared to the Rh‐ group [coefficient: ‐8.33 (95% confidence interval: ‐15.4 to ‐1.25); p = 0.021].

Conclusions: Retinal structural indices are related to blood groups implying a genetic linkage. Clinicians should consider blood groups in the clinical evaluation of retinal structural indices to avoid misdiagnoses. It is also recommended that the optical coherence tomography devices include the blood group in their databases.