Alanine aminotransferase and high sensitivity C-reactive protein: correlates of cardiovascular risk factors in youth.

OBJECTIVE

The association between high-sensitivity C-reactive protein (hs-CRP) and alanine aminotransferase (ALT) with clinical/metabolic variables was evaluated in overweight Brazilian children and adolescents.

STUDY DESIGN

Oral glucose tolerance test was performed in 407 students (273 overweight/obese, 11.3 +/- 3.1 y). Measurements included body mass index (BMI), waist circumference (WC), blood pressure, lipids, insulin, hs-CRP, and ALT. Overweight/obese was defined using BMI z-score; insulin resistance (IR) by homeostatic model assessment: insulin resistance (HOMA-IR); and metabolic syndrome (MS) in accordance with the modified NCEP-ATPIII.

RESULTS

As weight increased, systolic blood pressure (SBP), diastolic blood pressure (DBP), triglycerides (TG), insulin, HOMA-IR, hs-CRP, ALT, ALT, hs-CRP, and AST and the number of MS components (nMSc) also increased (P </= .001 for all). Subjects with hs-CRP and ALT above the median had higher BMI z-score, WC, SBP, DBP, TG, AST, insulin, HOMA-IR, and nMSc than those with both markers below the median (P </= .002 for all). After adjustment for age, sex and ethnicity, BMI z-score (OR, 1.5; CI, 1.38 to 1.86; P < .001), WC (OR,1.3; CI, 1.19 to 1.43; P < .001) SBP (OR, 1.2; CI, 1.03 to 1.38; P = .015), DBP (OR, 1.4; CI, 1.15 to 1.69; P < .001), TG (OR, 1.8; CI, 1.29 to 2.62; P < .001), insulin (OR, 1.4; CI, 1.23 to 1.71; P < .001), HOMA-IR (OR, 1.2; CI, 1.09 to 1.29; P < .001) and nMSc (OR, 2; CI, 1.16 to 3.47; P = .012) were independently associated with high ALT and hs-CRP. For every 5-cm increase in WC and every 1-point increase in BMI z-score, there were a 1.3- and 1.5-fold greater chance of having increased ALT and hs-CRP, respectively.

CONCLUSIONS

Simultaneous measurements of ALT and hs-CRP should be considered as a screening test for metabolic syndrome and cardiovascular disease risk factors in overweight/obese children/adolescents.