TY - JOUR
T1 - Locus-Level Changes in Macular Sensitivity in Patients with Retinitis Pigmentosa Treated with Oral N-acetylcysteine
AU - Kong, Xiangrong
AU - Hafiz, Gulnar
AU - Wehling, Dagmar
AU - Akhlaq, Anam
AU - Campochiaro, Peter A.
N1 - Publisher Copyright:
© 2020 Elsevier Inc.
PY - 2021/1
Y1 - 2021/1
N2 - Purpose: To identify characteristics of loci associated with locus-level sensitivity loss or improvement during treatment with N-acetylcysteine (NAC) in retinitis pigmentosa (RP). Design: Retrospective analysis of prospectively collected data in the FIGHT RP clinical trial. Methods: Patients (n = 30) were treated with 600, 1,200, or 1,800 mg of NAC twice daily for 3 months and then 3 times/day for 3 months. Microperimetry locus-level changes between baseline and month 6 were correlated with baseline characteristics of loci using regression models. The main outcome measurement was locus-level sensitivity change ≥6 dB. Results: Baseline mean sensitivity (3,468 loci; 51 evaluable eyes) was 7.7 dB and for foveal, parafoveal, and perifoveal loci were 20.2, 11.8, and 5.8 dB. During treatment, 287 loci (8.28%) increased ≥6 dB, and 119 of 1,613 loci with baseline sensitivity ≥6 dB decreased ≥6 dB (7.38%). A higher dose of NAC was associated with lower likelihood of sensitivity loss ≥6 dB (P = .033). Loci with low baseline sensitivity were more likely to decrease ≥6 dB (P = .034) but also more likely to increase ≥6 dB (P < .001). Foveal versus perifoveal loci (P < .001) and superior versus inferior loci (P = .005) were more likely to increase ≥6 dB. Conclusions: Higher doses of NAC reduced risk of macular loci sensitivity loss in RP. Greater sensitivity depression reversibility in the fovea during treatment suggests that high foveal cone density protects cones from irreversible loss of function in RP making them more likely to show improved function during NAC treatment.
AB - Purpose: To identify characteristics of loci associated with locus-level sensitivity loss or improvement during treatment with N-acetylcysteine (NAC) in retinitis pigmentosa (RP). Design: Retrospective analysis of prospectively collected data in the FIGHT RP clinical trial. Methods: Patients (n = 30) were treated with 600, 1,200, or 1,800 mg of NAC twice daily for 3 months and then 3 times/day for 3 months. Microperimetry locus-level changes between baseline and month 6 were correlated with baseline characteristics of loci using regression models. The main outcome measurement was locus-level sensitivity change ≥6 dB. Results: Baseline mean sensitivity (3,468 loci; 51 evaluable eyes) was 7.7 dB and for foveal, parafoveal, and perifoveal loci were 20.2, 11.8, and 5.8 dB. During treatment, 287 loci (8.28%) increased ≥6 dB, and 119 of 1,613 loci with baseline sensitivity ≥6 dB decreased ≥6 dB (7.38%). A higher dose of NAC was associated with lower likelihood of sensitivity loss ≥6 dB (P = .033). Loci with low baseline sensitivity were more likely to decrease ≥6 dB (P = .034) but also more likely to increase ≥6 dB (P < .001). Foveal versus perifoveal loci (P < .001) and superior versus inferior loci (P = .005) were more likely to increase ≥6 dB. Conclusions: Higher doses of NAC reduced risk of macular loci sensitivity loss in RP. Greater sensitivity depression reversibility in the fovea during treatment suggests that high foveal cone density protects cones from irreversible loss of function in RP making them more likely to show improved function during NAC treatment.
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U2 - 10.1016/j.ajo.2020.08.002
DO - 10.1016/j.ajo.2020.08.002
M3 - Article
C2 - 32795434
AN - SCOPUS:85095736483
SN - 0002-9394
VL - 221
SP - 105
EP - 114
JO - American journal of ophthalmology
JF - American journal of ophthalmology
ER -