Study of Association of Serum Prolactin Levels with Insulin Resistance in Type 2 Diabetes Mellitus Patients

OBJECTIVE: Prolactin (PRL) regulates glucose metabolism and insulin sensitivity. The study aimed to evaluate the role of PRL in glucose homeostasis and its association with insulin resistance in patients with diabetes mellitus (DM). METHODS AND MATERIALS: This cross-sectional, observational study included 100 patients (25–60 years) with T2DM. Primary information including demographics, anthropometric measurements, and biochemical measures (complete blood count, glucose parameters, liver and kidney function test, lipid profile, thyroid function test, serum fasting insulin levels, serum PRL levels) was collected. RESULTS: A total of 100 patients, 50 men and 50 women (25 premenopausal and 25 postmenopausal), were enrolled in this study. The correlation between serum cholesterol and PRL was found to be statistically non-significant (P = 0.129) in men and significant (P = 0.041) in women. There was an inverse relationship between fasting plasma glucose and serum PRL levels in both men (r = −0.88; P < 0.0001) and women patients (r = −0.768; P < 0.0001). Negative correlation between postprandial plasma glucose and PRL was found to be statistically significant (r = −0.398; P = 0.048) in postmenopausal women. The comparison in both men and women indicated an inverse correlation between serum PRL and glycated haemoglobin levels. There was a significant negative correlation between homeostasis model assessment-estimated insulin resistance (HOMA-IR) and PRL levels in both men (r = −0.362; P = 0.039) and women patients (r = −0.362; P = 0.003). Homeostasis model assessment of β cell function (HOMA-β), which directly correlates with residual pancreatic beta cell function, was positively correlated with prolactin levels, irrespective of gender and menopausal status of female subjects. CONCLUSION: Serum PRL levels correlate with improved glycaemic control.