|LETTER TO EDITOR
|Year : 2021 | Volume
| Issue : 3 | Page : 365-366
Comment on: Assessing the risk of retinopathy in indian patients using hydroxychloroquine for rheumatic and musculoskeletal diseases: A retrospective observational study
Manesh Manoj, Rasmi Ranjan Sahoo, Anupam Wakhlu
Department of Rheumatology, King George's Medical University, Lucknow, Uttar Pradesh, India
|Date of Submission||26-Dec-2020|
|Date of Acceptance||27-Dec-2020|
|Date of Web Publication||21-Sep-2021|
Dr. Anupam Wakhlu
Department of Rheumatology, King George's Medical University, Lucknow - 226 020, Uttar Pradesh
Source of Support: None, Conflict of Interest: None
|How to cite this article:|
Manoj M, Sahoo RR, Wakhlu A. Comment on: Assessing the risk of retinopathy in indian patients using hydroxychloroquine for rheumatic and musculoskeletal diseases: A retrospective observational study. Indian J Rheumatol 2021;16:365-6
|How to cite this URL:|
Manoj M, Sahoo RR, Wakhlu A. Comment on: Assessing the risk of retinopathy in indian patients using hydroxychloroquine for rheumatic and musculoskeletal diseases: A retrospective observational study. Indian J Rheumatol [serial online] 2021 [cited 2021 Dec 6];16:365-6. Available from: https://www.indianjrheumatol.com/text.asp?2021/16/3/365/313584
We read with interest the recent article by Roy et al. titled “Assessing the Risk of Retinopathy in Indian Patients using Hydroxychloroquine for Rheumatic and Musculoskeletal Diseases: A Retrospective Observational Study” and commend their work done to collect such a large body of data on hydroxychloroquine retinopathy (HCQR) from India. However, in this study, the authors have defined HCQR as either a single screening test abnormality (termed possible retinopathy) or those with abnormalities in at least one subjective and one objective test (definite retinopathy), thus possibly calculating an increased prevalence of HCQR. The reported prevalence of early-onset HCQR is alarming, especially given the small doses used and that hydroxychloroquine (HCQ) is contraindicated and to be stopped in those with HCQR. However, only one patient reportedly had visual symptoms. Moreover, details on whether HCQ was withdrawn or dose reduced are not available, adding complexity to the therapeutic implications. We believe, however, that in accordance with the American Academy of Ophthalmology 2016 and the Royal College of Ophthalmologists 2018 guidelines,, the patients with “possible retinopathy” should not be designated having HCQR but be closely followed up so that they are not denied HCQ. Most patients in the study were obese, with a mean body mass index (BMI) of 26.29 ± 5.58. Browning and Lee proposed that a HCQ dose of ≤5 mg/kg real body weight (RBW)/day tends to overdose in short, obese individuals and “ideal body weight” may be used instead, though the study reports no association between BMI and retinopathy.
The mean daily dose/kg RBW/day of patients, both with and without retinopathy, was around 3.5 mg and was significantly lower than the standard recommended dose. Among 842 patients treated with HCQ for 1–5 years, 103 had retinopathy; this is surprising given that guidelines recommend screening only after 5 years of the initial normal ophthalmologic assessment in asymptomatic patients, if the mean daily dose is as per recommendations. Although fundus autofluorescence is considered almost as sensitive to multifocal electroretinography (mfERG), there was a significant discordance between the two tests in detecting retinopathy in the study. Browning and Lee have suggested that tests such as mfERG may classify some healthy patients as having retinopathy (high negative predictive value). When comparing the different protocols for Humphrey visual field (HVF) (10-2, 24-2, and 30-2), only 9.8% and 3.3% of patients underwent testing for the latter two; the latter two may be more significant to pick up HCQR in Indians. A recent study including 110 patients by Manoj et al. (unpublished data) also showed possibly better detection of HCQR by the 30-2 protocol. Melles and Marmor also showed increased involvement on the 30-2 protocol in an Asian population, though only two East Indians were included. Given differences between Indians and the Far East population, generalization may not be appropriate. The association of HCQR with age could possibly be due to prolonged drug use, though that data are not available. There is an emergent need to enlighten physicians with regard to optimal dosing of HCQ.
Financial support and sponsorship
Conflicts of interest
There are no conflicts of interest.
| References|| |
Roy AN, Samala V, Kumar YA, Fatima SS. Assessing the risk of retinopathy in Indian patients using hydroxychloroquine for rheumatic and musculoskeletal diseases: A retrospective observational study. Indian J Rheumatol [Epub ahead of print]. Available from: https://www.indianjrheumatol.com/preprintarticle.asp?id=301572
[Last accessed on 2020 Dec 25].
Yusuf IH, Foot B, Galloway J, Ardern-Jones MR, Watson SL, Yelf C, et al
. The Royal College of Ophthalmologists recommendations on screening for hydroxychloroquine and chloroquine users in the United Kingdom: Executive summary. Eye (Lond) 2018;32:1168-73.
Marmor MF, Kellner U, Lai TY, Melles RB, Mieler WF. American Academy of Ophthalmology Statement: Recommendations on screening for chloroquine and hydroxychloroquine retinopathy (2016 Revision). Ophthalmology 2016;123:1386-94.
Browning DJ, Lee C. Somatotype, the risk of hydroxychloroquine retinopathy, and safe daily dosing guidelines. Clin Ophthalmol 2018;12:811-8.
Melles RB, Marmor MF. The risk of toxic retinopathy in patients on long-term hydroxychloroquine therapy. JAMA Ophthalmol 2014;132:1453-60.