Do patients with RA on MTX and FA 5 mg daily need to continue FA long term?

August 22, 2004

Do patients with rheumatoid arthritis established on methotrexate and

folic acid 5 mg daily need to continue folic acid supplements long term?

Background. It is postulated that some aspects of methotrexate toxicity

may be related to its action as an anti-folate. Folic acid (FA) is often

given as an adjunct to methotrexate therapy, but there is no conclusive

proof that it decreases the toxicity of methotrexate and there is a

theoretical risk that it may decrease the efficacy of methotrexate.

Objectives. To look at the effect of stopping FA supplementation in UK

rheumatoid arthritis (RA) patients established on methotrexate <20 mg

weekly and FA 5 mg daily, to report all toxicity (including absolute

changes in haematological and liver enzyme indices) and to report

changes in the efficacy of methotrexate.

Methods. In a prospective, randomized, double-blind, placebo-controlled

study, 75 patients who were established on methotrexate <20 mg weekly

and FA 5 mg daily were asked to stop their FA and were randomized to one

of two groups: placebo or FA 5 mg daily. Patients were evaluated for

treatment toxicity and efficacy before entry and then at intervals of 3

months for 1 yr.

Results. Overall, 25 (33%) patients concluded the study early, eight

(21%) in the group remaining on FA and 17 (46%) in the placebo group (P

= 0.02). Two patients in the placebo group discontinued because of

neutropenia. At 9 months there was an increased incidence of nausea in

the placebo group (45 vs 7%, P = 0.001). The placebo group had

significantly lower disease activity on a few of the variables measured,

but these were probably not of clinical significance.

Conclusions. It is important to continue FA supplementation over the

long term in patients on methotrexate and FA in order to prevent them

discontinuing treatment because of mouth ulcers or nausea and vomiting.

Our data suggest that FA supplementation is also helpful in preventing

neutropenia, with very little loss of efficacy of methotrexate.

I'll tell you where to go!

Mayo Clinic in Rochester

s Hopkins Medicine

Recommended Posts