Fasting Plasma Total IGF-1 and Bile Acids Levels Correlate With the Disease Prognostic Indices in Type 2 Diabetic Patients

Abstract

Although they are pathophysiologically involved, evidences inconsistently highlight a relationship between type 2 diabetes
mellitus (T2DM) and its prognosis with variation in circulating levels of each of bile acids (BAs) and Insulin-like growth factor1 (IGF-1). We aimed to investigate the possible role of BAs and IGF-1 in the prediction of T2DM and its complications in Saudi
patients. Their fasting plasma levels were correlated to each other and to the disease clinical and biochemical prognostic indices.
This is an analytical cross-sectional Tertiary care center-based study. We consecutively included 184 hospital-diagnosed T2DM
patients and 113 healthy controls from their accompanying relatives. Anthropometrics, demographics and disease history were
recorded. Fasting plasma levels of total BAs, lipids and glucose were assayed colorimetrically, and, total IGF-1, hemoglobin A1c
(HbA1c), insulin, and C-reactive protein (CRP) were quantitatively immunoassayed. Atherogenic index of plasma (AIP) and
homeostatic model assessment of insulin resistance (HOMA-IR) were calculated. Diabetic patients were stratified by disease
severity score and treatment score for association analysis. Correlations among parameters were assessed. Area under the receiver
operating characteristic (ROC) curve (AUC) assessed the discriminative power of BAs and IGF-1 vs. prognostic indices. Our
main outcomes were correlation among BAs and IGF-1 with diabetes prognostic indices. Majority of patients were overweight,
females, <60 years old and had complications. Patients showed significant increase in all studied biochemical parameters than
controls, except for total BAs; particularly with advancement of age and BMI. AUC showed that CRP, AIP, IR and HbA1c were
better predictors of disease complications and that BAs level was the single best predictor of absence of complications. Binary
logistic regression showed that only age and treatment score significantly predicted the presence of complications. In conclusion,
IGF-1 can be a monitoring marker and BAs can predict the absence of complications in T2DM. Further prospective researches
are needed to elucidate these conclusions in larger multicenter and longitudinal studies that take in consideration other limitations
of this study.