THE HYPERTRIGYLCERIDEMIC WAIST FOR THE DIAGNOSIS OF METABOLIC SYNDROME
Author Block: MF Matangi, DW Armstrong, C Onochie
PURPOSE. Recent data has suggested that the simple measurements of waist circumference (WC) and serum triglycerides (TG) can be used to diagnose the presence of the metabolic syndrome. The algorithm in males is a WC >90cm and TG >2.0mmol/l. For females the algorithm is a WC >85cm and TG >1.5mmol/l. This algorithm is said to have a >80% accuracy for the diagnosis of the metabolic syndrome when compared to the NCEP ATP III criteria. The purpose of our investigation was to evaluate these algorithms for the diagnosis of metabolic syndrome in our patients.
METHODS. Patients with all required data were extracted and analyzed from CARDIOfile, our cardiology database. The data required were, WC, TG, HDL cholesterol, blood pressure and fasting blood sugar (FBS). Only patients with blood work within 30 days of the office visit were included. Patients with an established diagnosis of either diabetes mellitus or those with a FBS >7.0mmol/l were excluded. There were 408 patients, consisting of 226 males and 182 females, who fulfilled all criteria that make up the study population. Calculations were made for sensitivity, specificity, positive predictive value (PPV), negative predictive value, (NPV), accuracy and overall prevalence using NCEP ATP III diagnostic criteria as the gold standard for the diagnosis of metabolic syndrome.
RESULTS. See Table 1.
CONCLUSIONS. This simple algorithm has a high specificity but a relatively low sensitivity for the clinical diagnosis of metabolic syndrome. The overall accuracy is consistent with previously reported data at 82.1%. The disadvantage of this algorithm is the low sensitivity, which may necessitate a need for further testing in a number of patients.
|MS (+ve) ATP III||MS (-ve) ATP III||Total|
|MS WC/TG (+ve)||98||19||117||PPV 83.8%|
|MS WC/TG (-ve)||54||237||291||NPV 81.4%|
|Sensitivity 64.4%||Specificity 92.6%||Accuracy 82.1%|