15 March 2021
Conflicting international advice on baseline retinal testing for HCQ patients
The Royal College of Ophthalmologists (RCOphth) in the UK has recently released revised guidelines for baseline retinal screening of patients prescribed hydroxychloroquine (HCQ) and chloroquine, endorsed by the British Society for Rheumatology (BSR). The new recommendations do not support baseline testing for patients.
The previous RCOphth guidelines, which formed the basis of the BSR DMARD guidelines, “introduced a significant burden on clinical teams, and some services were unable to deliver them,” according to an editorial in Rheumatology. While not supporting baseline testing, the new recommendations state that for patients with additional risk factors for retinal toxicity annual monitoring should begin after one year of treatment, and after five years for all other users.
“The new RCOphth recommendations are expected to increase the efficiency and reduce the cost of delivering monitoring services without reducing the overall diagnostic yield,” said the editorial authors, noting that “improvements in the efficiency and cost-effectiveness of the monitoring protocol are expected to improve access to monitoring for individuals at risk of sight loss”.
Weeks later, the American College of Rheumatology released its updated HCQ guidelines with respect to retinal toxicity in a joint statement with the American Academy of Ophthalmology, the American Academy of Dermatology and the Rheumatologic Dermatology Society.
In contrast to the UK guidelines, these guidelines continued to recommend a baseline retinal exam within the first few months of taking HCQ to rule out underlying retinal disease that may contraindicate HCQ use.
Melbourne-based rheumatologist Associate Professor Alberta Hoi said, “Obviously the US and UK have different guidelines as they stand, but in principle follow a few similar observations. The difference in the guidelines is related to the healthcare model and access to services.”
With limited access to monitoring services behind the change to UK guidelines, said Professor Hoi, “the removal of baseline screening is not unreasonable, as the first screening visit is highly unlikely to diagnose HCQ retinal toxicity, but rather is used as a reassurance exercise to ensure the patient does not have any baseline abnormality that warrants follow up.
“I think the more important aspect of the monitoring is recognising the at-risk groups – that is, people on higher dose, renal impairment, tamoxifen user, and anyone with pre-existing macular disease,” she added.
There is no national guideline in Australia, but Professor Hoi and her colleagues developed a local one with their ophthalmology team to make it easier for HCQ prescribers and patients to get the right screening.
“At Monash we still recommend the baseline screening, but suggest this can be done any time within the first six months of starting HCQ which is in line with the US screening guideline,” said Professor Hoi, head of the lupus clinic at Monash Medical Centre.
In terms of costs of the screening in Australia, the automated visual field testing is available from most optometrists and attracts a Medicare rebate. However, the availability of ocular coherence tomography is more limited and not covered by Medicare, making it more costly for patients.
“While we recommend doing both tests, we often discuss it with patients so they understand,” said Professor Hoi.
UK guidelines: Rheumatology 2021, 9 February
US guidelines: Arthritis & Rheumatology 2021, 9 February