BackgroundObesity epidemic has impacted practically every area of health including care of patients with RA. Adipose tissue is an active organ that produces pro-inflammatory molecules. A significant treatment challenge remains is the standard dose of RA medications may not attain same concentrations at sites of inflammation in obese vs non-obese patients thus making them less effective.ObjectivesThe study aim was to determine whether obesity represents a risk factor for a poor remission in RA requiring biologic therapies. Obesity may be associated with more severe and refractory inflammation through increased levels of inflammatory adipocytokines leptin, resistin or visfatin or decreased levels of the anti-inflammatory adipocytokine adiponectin. We retrospectively analysed 178 patients diagnosed with RA at East Kent University Hospitals.MethodsData analysed for age, sex, disease duration, prior DMARD, positivity RF and anti-CCP antibodies and response to biologics DAS28 score pre-treatment and at 6 months were analysed.Main aim was to analyse any difference between obese and non-obese patients in terms of their response to treatment. Obese patients were defined with a BMI of 30 or above.ResultsSee Table 1.Table 1.Demographics and Baseline CharacteristicsVariableCategoryNon-Obese (n=95)Obese (n=83)P-value
SexFemale61 (64%)66 (80%)
0.02
Male34 (36%)17 (20%)Age53±1250±130.08Duration disease8 [6, 11]12 [7, 14]
<0.001
Rheumatoid factorNegative20 (21%)60 (72%)
<0.001
RF12 (13%)8 (10%)CCP17 (18%)0 (0%)RF/CCP46 (48%)15 (18%)CRP35 [10, 51]24 [7, 40]
0.02
ESR37 [14, 59]28 [17, 45]0.57MTX15.5±9.213.5±9.60.15AdministrationInfusion4 (4%)5 (6%)0.74Subcutaneous91 (96%)78 (94%)DAS pre-treatment5.6±0.75.4±0.80.06Results suggested that there were significant differences between two groups for sex, duration of disease, RF and CRP. There was also some evidence of difference between groups in terms of their age and pre-treatment DAS28 score but these differences were only of borderline statistical significance. There was smaller proportion of males in the obese group with 20% male compared to 36% of non-obese patients. Obese patients had on average a longer disease duration with a median of 12 years compared to a median of 8 years for the non-obese group. The RF status also varied between groups with a much higher proportion of patients in the negative category for the obese group. CRP values were significantly lower in the obese group with a median of 24 compared to 35 in the non-obese group.Table 2.EULAR response between obese and non-obese patientsEULAR responseNon-Obese N (%)Obese N (%)P-value
No response9 (9%)32 (39%)<0.001Moderate response40 (42%)36 (43%)Good response46 (48%)15 (18%)<0.001Non-Obese (n=95), Mean ± SDObese (n=83), Mean ± SDDAS28 post-treatment3.2±1.04.2±1.3DAS28 reduction2.4±1.31.1±1.3Non-obese had the best response with 48% good response compared to18% of the non-obese group with post treatment mean DAS28 score of 3.2 and mean reduction of 2.4.ConclusionsObesity is important factor that impacts treatment and ou...