discriminatory performance of body mass index, waist circumference, waist-to-hip ratio and waist-to-height ratio for detection of metabolic syndrome and their optimal cutoffs among Iranian adults

The superiority of either of body mass index [BMI], waist circumference [WC], waist-to-hip ratio [WHR] and waist-to-height ratio [WHtR] for prediction of metabolic syndrome [MetS] is remained controversial in Asian population. The objective of this study was to compare the discriminative capacity of either of these measures in prediction of non-adipose components of MetS. In this population-based cross sectional study, 1000 representative samples of adults were recruited in Babol, northern Iran. The demographic, anthropometric measures and blood pressure were determined by standard method. Fasting plasma glucose [FPG], triglycerides [TG], total cholesterol [CHL], high density lipoprotein [HDL] cholesterol levels were measured with enzymatic methods by an auto analyzer. The presence of two or more any of four non-obese components were considered as MetS. The diagnostic accuracies [AUCs] of four different measures were rather similar. While AUC for BMI [AUC=0.684; 95% CI: 0.633, 0.736] slightly tended to be higher than that of WC [AUC=0.640; 95% CI: 0.587, 0.693] and WHtR [AUC=0.649; 95% CI: 0.596, 0.701] in men but the accuracy of WC [equivalently WHtR [AUC=0.708; 95% CI: 0.664, 0.751] is tended to be greater than that of BMI in women. The optimal cut-off value for WC was higher in men compared with women. Overall, BMI, WC and WHtR were significant predictors of MetS equally but WC [equivalently WHtR] was a better predictor than BMI and WHR in women. The optimal cut-offs of WC are lower compared with western population for men but not for women

prevalence and diagnostic performance of anti-cyclic citrullinated peptide antibody in rheumatoid arthritis: the predictive and discriminative ability of serum antibody level in recognizing rheumatoid arthritis

The utility of anticyclic citrullinated peptide [anti-CCP] antibody in the diagnosis of rheumatoid arthritis [RA] varies across different studies. We determined the diagnostic performance and predictive ability of anti-CCP for RA. We studied 201 patients with RA and compared them with 208 non-RA patients as controls. RA patients included in the study fulfilled the American College of Rheumatology revised criteria and patients with other diseases as well as those with undifferentiated arthritis [UIA] were used as controls. Anti-CCP was measured by enzyme-linked immunosorbent assay [ELISA] and rheumatoid factor [RF] by the agglutination method. The optimal cutoff value and diagnostic accuracy were determined using receiver operating characteristics [ROC] curve and area under the curve [AUC].The sensitivity and specificity were determined by comparison of RA patients with non-RA controls. The anti-CCP test was positive in 164 patients with RA for a sensitivity of 81.6%, specificity of 87.5%, and overall accuracy of 84.6%. The respective values for RF were 75.6%, 86.5% and 84.4%. The anti-CCP test discriminated RA from non-RA patients with high accuracy [AUC=0.889 [0.017] 95% CI, 0.856-0.952, P=.001], and predicted progression of UIA to RA with moderate accuracy [AUC=0.733 [0.069], 95% CI 0.60-0.87, P<.006] at a sensitivity of 75% and a specificity of 68.1%. Among 60 UIA patients, in 16 [26.7%] who differentiated to RA, the mean [standard deviation] for anti-CCP was significantly higher than in 24 [40%] patients who progressed to non-RA [134.8 [172] vs 46 [86] U/mL, P<.01]. These findings indicate that anti-CCP yields higher sensitivity and overall accuracy, but slightly greater specificity than RF for diagnosis of RA. Anti-CCP positivity, particularly a higher level of serum antibody in patients with UIA, may be a predictor of subsequent RA