Evaluation of ganglion cell complex in patients taking hydroxychloroquine.

Background: To evaluate the ganglion cell complex thickness in patients taking oral hydroxychloroquine.

Methods: In this hospital-based, cross-sectional, non-interventional, comparative study, 87 eyes of 87 patients taking hydroxychloroquine were recruited. All the patients underwent complete ophthalmological evaluation along with dilated fundus examination. Patients were divided into two groups based on the duration of hydroxychloroquine intake: Group 1 (62 patients having duration of hydroxychloroquine intake < 5 years) and Group 2 (25 patients having duration of hydroxychloroquine intake ≥ 5 years). Age and gender-matched healthy volunteers with normal ocular findings were taken as controls. Average, superior, inferior GCC thickness, focal loss volume, and global loss volume were measured by RTvue XR Avanti SD-OCT.

Results: The average, superior, and inferior GCC thicknesses were significantly reduced in both Group 1 (< 5 years) and Group 2 (≥ 5 years) as compared to controls (p < 0.001). In Group 1, mean GCC values were 94.70 ± 6.34 μm (average), 94.43 ± 6.28 μm (superior), and 94.74 ± 6.81 μm (inferior), while the corresponding values in controls were 99.79 ± 4.61 μm, 99.38 ± 4.63 μm, and 99.97 ± 4.61 μm. Likewise, FLV and GLV in Group 1 were 1.76 ± 2.5% and 4.07 ± 3.27%, significantly higher than in controls (0.72 ± 0.45% and 1.39 ± 1.1%, respectively; p = 0.002 for FLV, p = 0.001 for GLV). Similarly, in Group 2, mean GCC thicknesses were 92.70 ± 6.39 μm (average), 92.44 ± 5.92 μm (superior), and 93.32 ± 7.25 μm (inferior), all significantly lower than in controls (p < 0.001). While GLV was significantly elevated in Group 2 (4.46 ± 4.42%; p-0.003), the difference in FLV (1.23 ± 1.12%) was not statistically significant compared to controls (p-0.077).

Conclusion: The Ganglion Cell Complex thickness was significantly thinner in patients taking hydroxychloroquine along with elevated Focal Loss Volume % and Global Loss Volume %. However, no statistically significant correlation was observed between GCC thickness and duration of hydroxychloroquine use.