Conference Coverage

Reduced-frequency methotrexate monitoring causes no harm


 

FROM BSR 2022

Reducing the frequency of routine blood monitoring for methotrexate in patients with rheumatoid arthritis during the COVID-19 pandemic was associated with no adverse outcomes for patients, British researchers have found.

Similar laboratory results were recorded in patients who were switched from testing once per month to once every 3 or 5 months, Natasha Wood, a general practice trainee at North Devon District Hospital in Barnstaple, England, reported at the annual meeting of the British Society for Rheumatology.

Medicine vial of Methotrexate, made by APP Pharmaceuticals. Vial is partially full. sshepard/iStock

“Less frequent monitoring did not result in patient harm,” she said.

“There’s an increasing evidence base; we wonder whether now’s the time to reconsider our DMARD-monitoring strategy,” Ms. Wood said.

Changes in monitoring because of pandemic

Methotrexate monitoring is important to minimize the risk of harm to patients, and it is recommended that standard laboratory tests, such as a complete blood count, creatinine, and liver enzymes are measured regularly. Indeed, both the BSR and the American College of Rheumatology have specific recommendations on the monitoring of methotrexate and other conventional synthetic disease-modifying antirheumatic drugs (csDMARDS).

“The BSR used to advise for monthly blood tests in patients taking methotrexate,” Ms. Wood said, but the BSR moved to recommend testing patients on a stable dose every 3 months in 2017.

“Things of course changed again rapidly with COVID, with the BSR quickly updating their guidelines advising for less frequent monitoring in this patient group,” Ms. Wood said.

As a result, the North Devon Clinical Commissioning Group, which covers the hospital where Ms. Wood works, agreed to allow testing every 6 months for patients on a stable methotrexate dose. “This was across specialties, so not just rheumatology, but dermatology and gastroenterology as well,” she said.

“This provided us with a really exciting and unique opportunity to look at this patient group and see what happened,” Ms. Wood explained.

Effect of less frequent monitoring

At the meeting, Ms. Wood presented the results of an audit of 854 patients found via a search of hospital pathology records who were stable on methotrexate monotherapy for at least 12 months.

Two subanalyses were performed: One looked at patients who had changed from blood testing once every month to once every 3 months (n = 229) and the other looking at a group of 120 patients who had gone from testing once every 3 months to approximately every 5 months.

The mean age of patients was 67 for monthly testing, 69 for testing every 3 months, and 66 for testing about every 5 months, with around two-thirds of patients being of female sex.

A comparison of the number of blood tests performed to the end of April 2020 with the number performed to the end of April 2021 showed that there had mainly been a shift from testing once per month to once every 3 months, with some patients being tested in line with the revised BSR guidelines at around 5 months.

“Interestingly, a third of this group had no changed monitoring frequency despite the change in guidelines,” Ms. Wood said.

“Prepandemic, most patients [were] having monthly bloods despite BSR advice from 2017, and despite the pandemic with the updated shared care guidelines,” patients were still having blood drawn every 3 months, Ms. Wood noted. This perhaps needs further investigation and consideration to understand why recommended changes to the frequency of testing are not being adhered to.

The overall distribution of laboratory findings was similar among those who went from testing once per month to once every 3 months and from every 3 months to every 5 months. This included the distribution of neutrophils, whole blood counts, and alanine aminotransferase. There were some changes for platelets, mean cell volume, and the estimated glomerular filtration rate, but these were not clinically significant.

“Abnormal blood results aren’t common in stable methotrexate monotherapy patients,” Ms. Wood reported. “Where abnormalities did occur, it was in the context of patients being concurrently unwell and symptomatic.”

Time for patient-initiated testing?

There are several advantages of less frequent methotrexate monitoring, Ms. Wood said. One is the practicalities of getting to and from appointments, particularly in remote locations, such as where she works.

In addition to reducing workloads and pressure on already busy hospitals and primary care, this could have a huge environmental impact, she suggested.

Moreover, “moderate-quality evidence” supports the current monitoring frequency recommendation.

“We know that our numbers are small – we’re a small center – but our findings are consistent with much larger studies across the U.K.,” Ms. Wood said.

“We wonder whether there’s the possibility of moving towards annual monitoring with good safety netting and patient education for additional blood tests if they are unwell,” she said, adding that “now may be the time for patient-initiated methotrexate monitoring.”

Ms. Wood disclosed Janssen sponsorship for attending the BSR 2022 annual meeting.

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