The Association Between 25 Hydroxy Vitamin D And Metabolic Syndrome In Systemic Lupus Erythematosis

ObjectiveSystemic lupus erythematosus(SLE) is a common chronic and systemic autoimmune disease, with various clinical presentations and diverse autoantibodies,especially anti-nuclear antibody. With the survival rate reaching to 80%-90%, the long-term prognosis of SLE has acquired increasing attention. Because the main reason for death after 5 years owed to cardiovascular disease(CVD) which caused by atherosclerosis(AS), and researches in China and from abroad showed higher incidence of metabolic syndrome(MS)and MS was associated with AS and CVD,exploration of the mechanism, risk factor about MS in SLE became a hotspot for research. In recent years, a lot of studies have suggested the regulating effect of vitamin D for metabolism and immune, the lower level of vitamin D in patients with SLE, and the obvious association between vitamin D and MS in general population.From which, we can easily guess that vitamin D may be a influencing factor for MS and CVD in SLE, However, there has been few studies confirmed this suppose. The objective of our work was to determine the incidence of serum 25-hydroxy vitamin D(25(OH)D) deficiency and the relationship with MS in SLE patients.MethodsThis was a cross-sectional study involving 113 pre-menopausal SLE patients from the Department of Rheumatology & Immunology in the first affiliated hospital of Zhengzhou University from March to May of 2015 who must be aged over 18 years and satisfy the 2009 ACR classify criteria for SLE without pregnancy,malabsorption, thyroid and parathyroid diseases, serious infection, vital organ failure,cancer and a previous history of other connective tissue disease. A control group with115 subjects matched for age, sex, race, and the place of residence was recruited from Department of the Physical Examination Center in the first affiliated hospital of Zhengzhou University. We de?ned MS following the joint interim statement about Chinese of IDF/ NHLBI/ AHA/ WHF/ IAS/ IASO in 2009.In addition to the measurement of the concentration of the serum 25(OH)D responsible for vitamin D level, our relevant data were collected and these included demographic and anthropometric information, and MS components such as age,height, weight, waist circumference(WC), blood pressure(BP), fasting blood-glucose(FBG), triglycerides(TGs) and high-density lipoprotein(HDL). Moreover, clinical characteristic and data, such as age at diagnosis, duration of the disease(period between SLE diagnosis and recruitment), C-reactive protein(CRP), erythrocyte sedimentation rate(ESR), complements and SLE Disease Activity Index(SLEDAI)were also evaluated for the patient group. Furthermore, the following therapeutic variables were recorded: current dosage of prednisone or equivalent medication,application of hydroxychloroquine(HCQ). Vitamin D supplementation and photoprotection measures were also taken into account. At first, we made comparison of the concentration of the serum 25(OH)D and the incidence of MS between the patients and the controls. Then separate SLE patients in two group according to the presence or absence of MS, and compared the clinical characteristic, disease activity and therapeutic data. At last, evaluated the associations between 25(OH)D,components of MS, and MS respectively.Results1.Compared to the controls, the SLE patients has significant lower 25(OH)D level(21.3 ± 7.7 vs 24.1 ± 5.6 ng/ml, p<0.05) and higher prevalence of MS(30.1% vs13%, p<0.01).2.Compared to the patients without SLE, patients with SLE has lower 25(OH)D level(18.1 ± 6.9 VS 23.7 ± 7.8ng/ml, p<0.05), higher WC?body mass index(BMI)?BP ? FBG ? TGs and lower HDL(p<0.05). Patients in SLE-MS group has higher SLEDAI?CRP and current dosage of prednisone than that of the SLE-nMS group(p<0.05). Significant difference was not found involving duration of disease, renal involvement, ESR, complements?cumulative dosage of prednisone, the use of HCQ,immunosuppressant, calcium, vitamin D and photoprotection.3.25(OH)D was associated with increased MS prevalence(OR=0.920,P=0.012),decreased level of HDL(OR=1.059,P=0.033) and a higher level of FBG(OR = 0.810,P=0.004). These associations were still detectible after the adjustment with confounding factors, such as age, BMI, duration of disease, renal involvement,SLEDAI?CRP?ESR?complements and drug use.Conclusion1.The prevalence of 25(OH)D de?ciency was common in SLE.2.25(OH)D is associated with MS, FBG and HDL in SLE.