Metabolic syndrome: comparison of diagnostic capability among waist circumference and supine and upright...

Metabolic syndrome (MetS) is screened for or assessed by manual waist circumference (WC) measurements or adipose tissue evaluation using supine multidetector CT (MDCT). Currently, upright MDCT was clinically established and tested for different clinical aims. The purpose of this study was to directly compare the utility of metabolic disorder assessments and the diagnosis of MetS among WC, upright MDCT, and supine MDCT in a Japanese health checkup test cohort.

This study cohort consisted of 47 consecutive subjects who underwent WC measurements, blood tests, upright MDCT, and supine MDCT on the same day. In each subject, the total fat area (TFA), subcutaneous fat area (SFA), visceral fat area (VFA), and visceral-to-subcutaneous fat ratio (VSR) were semi-automatically assessed using upright MDCT and supine MDCT data. To compare each index on both CTs, as well as manual WC measurements between the MetS and non-MetS groups, Student's t-test was performed. Univariate regression analyses were performed to evaluate the relationship between each index and blood test results. Subsequently, receiver operating characteristic (ROC)-based positive tests were performed. Finally, the sensitivity, specificity, and accuracy were compared among all indexes from both CTs, and a manual WC measurement evaluation was conducted using McNemar's test.

Some indices showed significant differences between two groups (p < 0.05). All indices shows significant correlations with BMI, TG, HDL-cholesterol, uric acid, glucose, HbA1c, insulin, HOMA-IR, GOT (or AST), GPT (or ALT), or creatinine (manual WC measurement: - 0.58 ≤ r ≤ 0.87, p < 0.05; supine MDCT: - 0.61 ≤ r ≤ 0.84, p < 0.05; upright MDCT: - 0.64 ≤ r ≤ 0.91, p < 0.05). TFA and VFA on upright MDCT had significantly higher sensitivities than WCs determined from manual and supine MDCT as well as the VSR (p < 0.05).

Upright MDCT-derived adipose tissue indices showed preliminary potential for assessing metabolic syndrome, but larger prospective studies are needed to validate their clinical utility.