Patients with fibromyalgia syndrome (FMS) have impaired mobility and therefore get less sunlight exposure, we postulated that they may be at increased risk of developing osteoporosis (OP). The aim of this study was to assess and compare serum vitamin D level and bone mineral density (BMD) value in patients with primary FMS (PFMS) and healthy controls. A total of 50 patients with PFMS participated in this case-control study, and 50 healthy females who were age-matched to the patients were used as the control group. Venous blood samples collected from all subjects were used to evaluate serum 25-hydroxyvitamin D3 (25-OHD). BMD was measured at the lumbar spine (L2-L4) anteroposterior, femoral neck and forearm by dual-energy X-ray absorptiometry. Patients with PFMS had significantly lower serum 25-OHD than controls (15.1 ± 6.1 and 18.8 ± 5.4 ng/ml, respectively, p = 0.0018). Apart from the BMD in the lumbar spine, which was significantly lower in the PFMS patients compared with controls (p = 0.0012), no significant difference was found in other measures of BMD. Compared to PFMS patients who had serum level of the 25-OHD >20 ng/ml, the patients with 25-OHD ≤20 ng/ml are more likely to have impaired short memory (46.4 vs. 13.6%, respectively, p = 0.0136), confusion (50 vs. 18.2%, respectively, p = 0.0199), mood disturbance (60.7 vs. 27.3%, respectively, p = 0.0185), sleep disturbance (53.6 vs. 22.7%, respectively, p = 0.0271), restless leg syndrome (57.1 vs. 27.3%, respectively, p = 0.0346) and palpitation (67.9 vs. 36.4%, respectively, p = 0.0265). Serum level of the 25-OHD is inversely correlated with visual analogue scale (VAS) of pain (p = 0.016), Beck score for depression (p = 0.020) and BMD at lumbar spine (p = 0.012). The lumbar BMD inversely correlated with VAS of pain (p = 0.013) and Beck score for depression (p = 0.016). This study confirmed high prevalence of hypovitaminosis D among in patients with PFMS. This study confirmed the concept that FMS is a risk factor for OP. Based on this, an early nutrition program rich in calcium and vitamin D, appropriate exercise protocols, and medical treatment should be considered in these patients in terms of preventing OP development.

Reports suggest leptin, which was initially described as a hormone that regulates food intake and energy balance, has an intimate relationship, and interacts with the immune system. Leptin consumption in the synovial cavity in patients with rheumatoid arthritis (RA) reported to have protective effect against erosion. To determine the difference in serum leptin and synovial/serum leptin ratio between RA and control and to assess whether these parameters correlate with systemic inflammation in RA. Also, the hypothesis that synovial/serum leptin ratio could be linked to joint erosion in RA was evaluated. The study subjects consisted of 40 consecutive patients with RA, 30 patients of them had knee effusion, and 30 controls. Ten of these controls had acute knee injury and their synovial fluid was obtained for comparison of synovial/serum leptin ratio with patients with RA. The mean serum leptin in patients with RA was significantly higher than controls. Also, the synovial leptin and synovial/serum leptin ratio in the RA patients with effusion was significantly higher than in the 10 control subjects with traumatic effusion. Serum leptin in the 30 RA patients with effusion was higher than the matched synovial leptin. In RA patients with effusion, synovial/serum leptin ratio was also significantly higher in RA patients with erosion than RA patients without erosion. Serum leptin level and synovial/serum leptin ratio are significantly correlated with the RA duration, DAS28, ESR, CRP, TNF-α, and IL-6. Finally, in regression analysis, only the synovial/serum leptin ratio was positively associated with erosion in patients with RA. In RA, there is a significant increase in circulating leptin levels and synovial/serum leptin ratio compared to non-RA controls. Serum leptin and synovial/serum leptin ratio are significantly in erosive RA than non-erosive RA. Both parameters are correlated with disease duration and parameters of RA activity. In regression analysis, only the synovial/serum leptin ratio was positively associated with erosion in patients with RA. These results indicate that local consumption of leptin in the joint cavity has a protective role against the destructive course of RA.

The role of paraoxonase (PON) and arylesterase (ARE) in the pathogenesis of inflammatory arthritis has been investigated, and their serum levels have been evaluated, but clinical study concerning PON1 and ARE and ankylosing spondylitis (AS) is little reported in literature. The aim of this study was to investigate PON1 and ARE activities in AS in comparison with healthy persons and their relation with the disease activity parameters. 35 AS patients and 35 healthy controls (matched for age and sex) participated. Disease activity of AS patients was assessed clinically according to the Bath AS disease activity index, and AS functional impairment was assessed using the Bath AS Functional Index. Serum samples were collected from all subjects to evaluate serum PON1, ARE activities, and lipid profile. The mean serum triglycerides, total cholesterol, and low density lipoprotein (LDL) were significantly higher in the AS patients than in controls, while the high-density lipoprotein (HDL) is significantly lower in the AS patients than controls. Serum PON1 and ARE activities were significantly lower in AS patients than in controls, while malondialdehyde (MDA) was significantly higher. AS patients with active disease had significantly higher serum triglycerides, total cholesterol, LDL and MDA while lower HDL, PON1 and ARE than those with no active AS. Decrease in the PON1/ARE activity leading to generation of oxidative stress may play an important role in the pathogenesis of AS. Moreover, it seems that activity of PON1/ARE in patients with AS is strictly correlated with the activity of the inflammatory process.

We found a significant decrease in serum leptin in FMS patients compared to controls and this decrease correlated with disease severity.