Use of MTX in the Elderly
The absorption and distribution of MTX are similar in the elderly and younger RA patients. However, as both metabolism and renal or biliary excretion of MTX might be affected by age, these parameters should be considered when using this drug. Neither hemodialysis nor peritoneal dialysis effectively clears MTX, while high-flux dialysis may be effective. MTX efficacy is equivalent in the young and elderly. The side-effect profile includes a higher frequency of gastrointestinal, liver and hematological toxicities in older patients, even though the overall profile is not qualitatively different. By contrast, a population-based study indicated that increasing age was associated with a greater tendency for discontinuation of MTX in patients with newly diagnosed RA. The potential for renal toxicity should always be considered when determining which dosage of MTX to use for RA therapy, and there is modest doubt that the dosage of MTX is especially critical in the elderly.