Background Only postmenopausal women were in the researcher's focus in the majority of publications on osteoporosis (OP) risk factors (RF) in RA female patients (pts). Meanwhile the data on OP RF in menstruating women presented in the rare available papers are not consistent.
Objectives To identify the major OP RF in RA female pts with normal menstrual cycle.
Methods 51 RA (based on ACR criteria) female pts with normal menstrual cycle aged 20 to 51 years (mean age 41,1±7,9) were examined. The following info was included in each individual pts' files: anthropometric parameters, social and demographic data, case history, clinical examination and lab findings, traditional OP RF, pts' joint status, comorbidities status, pain intensity assessments and VAS evaluation of pts' general health status. Axial bone mineral density (BMD) was measured with DEXA scan using Z-score calculator. Based on the OP status all pts were divided into 2 groups:pts with OP–16 (31,4%), and pts without OP–35 (68,6%).
Results Comparative analyses of the groups showed that: OP pts were younger vs the pts without OP (36,9±10 vs 42,8±6,3 years, p=0,02). Disease duration was comparable in both groups. Clinical manifestations of inflammation activity (mean DAS 28 score and hsCRP) were statistically significantly more pronounced in the OP group vs the pts without OP (4,91±1,39 vs 4,19±1,06, p=0,049; 27,8 (10,8–43,5) vs 7,4 (1,4–22,7) mg/L, p=0,02, respectively). High DAS 28 (50 vs 20,6%, RR=2,43, 95% CI 1,07–5,53, p=0,03) scores were more often documented in the OP pts. Pronounced feet and hand bone destruction based on the radiographic findings was documented in the majority of pts in both groups, although in the OP pts the joint space narrowing counts (97 (62,5–121) vs 73,5 (53–87), p=0,02) and the total Sharp score (98 (64,5–183) vs 89,0 (63–112), p=0,03) were statistically significantly higher. The OP pts were more often administered oral GCs (81,3 vs 37,1%, RR=2,19, 95% CI 1,34–3,57, p=0,004), as well as GCs -pulse therapy (56,3 vs 25,7%, RR=2,18, 95% CI 1,08–4,45, p=0,04), had higher GCs cumulative dose (18,8 (8,1–30,7) vs 6,4 (0,8–14,1)g, p<0,01), higher GC daily dose at the time of examination (8,8 (6,3–10) vs 5 (3,8–6,3)mg/day, p=0,01) and higher average daily dose in the previous year (8,8 (5–10) vs 3,8 (2,5–6,3)mg/day, p=0,01) versus the pts without OP. Analysis of traditional RF (low body weight/BMI, long immobilization periods, smoking, family history of OP and others) showed no difference between the two groups. Discriminant analysis revealed the following major OP RF in the RA female pts before menopause: RA activity (based on the Das 28 score) and GCs dose at the time of examination (given GCs therapy lasts ≥3 months). Meanwhile the patient's body weight and age at the onset of RA were identified as protective factors for BMD. Based on the abovementioned risk and protective factors and the derived coefficients the authors designed a formula allowing to predict of OP in female RA pts before menopause with high accuracy (area under the ROC-curve=0,833). The model accuracy is 85,1%.
Conclusions RA activity and GCs dose (GCs therapy duration ≥3 months) were identified as the major OP RF in young RA female pts before menopause, thus adequate and timely therapy aimed at obtaining RA control and achieving remission should be considered as key OP prevention strategy.
Disclosure of Interest None declared