Hormonal–lipid interplay in metabolic disorders: Evaluating the prolactin–testosterone ratio in diabetic and hypothyroid-diabetic patients with a special emphasis on thyroid dysfunction

Background: Metabolic disorders such as diabetes and hypothyroidism frequently coexist and share underlying disturbances involving hormonal imbalance, lipid dysregulation, and impaired glucose homeostasis. Prolactin and testosterone, individually and in combination, may play a significant role in these metabolic alterations. Aims and Objectives: To evaluate the prolactin–testosterone (PRL-T) ratio as a potential biomarker for assessing metabolic dysfunction in diabetic, hypothyroid, and hypothyroid-diabetic patients, with a special emphasis on thyroid status and lipid abnormalities. Materials and Methods: This cross-sectional study included 200 participants divided into four groups: diabetic, hypothyroid-diabetic, hypothyroid, and healthy controls. Hormonal markers (prolactin and testosterone), thyroid profile (TSH and free thyroxine), lipid parameters, and glycemic indices (fasting blood glucose and glycated hemoglobin) were measured and analyzed. Correlation analyses were performed to assess the association between the PRL-T ratio and metabolic variables. Results: The hypothyroid-diabetic group showed the highest PRL-T ratio (0.155 ± 0.02), followed by the hypothyroid group (0.114 ± 0.015). A significant positive correlation was observed between the PRL-T ratio and TSH levels ( r = 0.51, P < 0.001). The PRL-T ratio also correlated with lipid parameters, indicating its strong association with thyroid dysfunction–related dyslipidemia and glycemic imbalance. Conclusion: The PRL-T ratio integrates hormonal, glycemic, and lipid abnormalities, functioning as a sensitive biomarker of metabolic dysfunction in hypothyroid-diabetic patients. Routine assessment of this ratio may support early detection of metabolic deterioration and improve therapeutic decision-making in patients with combined thyroid and diabetic disorders.