AB0212 Clinical and sociodemographic characteristics associated with response to methotrexate (MTX) in a cohort of patients with rheumatoid arthritis (RA) naÏve to dmard

Abstract

BackgroundRA treatment involves starting early with a DMARD. MTX achieves good sustained response in 30–40% of patients (pts). When MTX response is insufficient add other DMARD by achieve RA remission. Different factors may affect the response to MTXObjectivesTo analyze the clinical and demographic characteristics related to response to MTX in RA pts DMARD-naïveMethodsWe enrolled between 2011 and 2015, pts>18years RA diagnosed (ACR 1987 criteria), treated firs with MTX monotherapy (MTXm). A case-control study (MTXm persistence with CRP-DAS28<3.2 and suspension of MTXm by ineffectiveness or toxicity, respectively) was performed. We collected information that can influence the response to MTXm by medical records review and patient survey. A descriptive and analitical study with SPSS statistics 21 was performedResultsWe included 222 pts (70 men and 152 women). The characteristics of cases (123) and controls (99) are shown in the table. The causes of MTXm suspension were remission (7), intolerance/toxicity (19) and inefficiency (79). MTX was discontinued in 40 (18.2%) pts, 28 (12.7%) of them by intolerance/toxicity. Of 123 (55.4%) responders, 71 (32.0%) were CRP-DAS28<2.6. MTXm response was associated with age at onset ≥60 years (χ2 18.47, p<0.01, OR 3.67), rheumatoid factor (RF) <100 IU (χ2 10.92, p<0.01, OR 3.16) and current smoking (χ2 12.71, p<0.01, OR 2.95). Tobacco was associated with RF+ (χ2 8.9 p<0.01 OR 2.59 (1.37; 4.89) and ACPA+ (χ2 4.49 p<0.05 OR 1.88 (1.04, 3.38). We found no association with gender, education, job, coffee, tea or alcoho drinks, comorbidities, cardiovascular risk, possitivity ACPA or FR, RA presentation, treatment delay, or corticosteroid use. We found no correlation between age of RA-onset and RF or ACPA levels and MTXm duration. MTXm persistence at 5 years was 59% pts and their median survival was 93 months (77.14 to 108.8). We only found significant differences in favor of non-smokers and RF<100Table 1.Clinical and sociodemographics characterisitics of RA patientsCharacteristicsRespondersNonrespondersStatistic Significancy n=125n=99 Age at onset (y) (mean, SD)53.48 (13.0)46.65 (11.5)t=4.08 p=00006Female n (%)80 (65.0)72 (72.7)nsCurrent Smokers n (%)23 (18.7)40 (40.4)χ2 12.7 (p<0,01)OR 2.95 (1.6, 5.4)Alcohol consumers n (%)35 (28.5)28 (28.3)nsComorbidity n (%)92 (74.8)61 (61.6)χ2 4.45 (p<0.05)OR 1.21 (1.0, 1.5)CV risk factors n (%)92 (74.8)81 (81.8)nsPolyarticular onset of AR n (%)61 (49.6)61 (61.6)nsExtraarticular involvement n (%)17 (13.8)21 (21.2)nsPossitive RF n (%)89 (72.4)79 (79.8)nsPossitive ACPA n (%)70 (60.3)64 (68.1)nsDuration of RA (m) (mean (SD)96.1 (63.1)96,0 (73.9)nsMTX toxicity n (%)47 (38.2)59 (59.6)χ2 10.0 (p<0.01)OR 2.38 (1.4, 4.1))MTX dose (mg) (mean, SD)15.6 (0.32)17.8 (0.37)t=-4.52 p=00001ConclusionsThe initial treatment of RA with MTX is an effective and safe option, with a high drug survival. MTX response was not associated with antibody positivity (RF or ACPA), but it was significantly better in non-smokers patients and RF <100. Smoking cessation could signific...