Endocrine Abstracts

Introduction: Renal function and glucose lowering therapy, particularly metformin, influence serum lactate concentration in patients with type 2 diabetes (T2D). However, seems to be an acute precipitating event that triggers hyperlactacidemia and metabolic acidosis. This study aims to assess prevalence of hyperlactacidemia in T2D patients who presented at emergency room (ER), calculate relative risk of hyperlactacidemia in diabetics under metformin, identify predictive factors for high lactate concentration and determine influence of hyperlactacidemia in patients’ prognosis.

Methods: Prospective study of consecutive T2D patients that attended our hospital’s ER. Exclusion criteria: organ transplantation, pregnancy, metastatic malignancy, HIV, pheochromocytoma, alcoholism, convulsions, severe hypoxemia, hemodynamic instability, severe hepatic dysfunction or any known cause of metabolic acidosis. Selected as controls non-diabetic patients observed during same period. Studied variables: age, sex, cause of visit, blood pressure, arterial blood gas analyses with lactate, glucose, creatinine, ALT, AST, GGT, C-reactive protein, drugs, history of heart failure, pulmonary disease or obesity, and destination. Statistical analysis was performed using SPSS 21.0.

Results: Total of 221 patients, 83 (37.6%) non-diabetics and 138 (62.4%) diabetics, of these 65 (47.1%) treated with metformin. Mean serum lactate and prevalence of hyperlactacidemia were significantly higher in T2D patients relatively to control group (2.1±0.1 vs 1.1±0.1, P<0.01 and 39.1 vs 3.6%, P<0.01 respectively), and in T2D patients under metformin compared to diabetics without this drug (2.7±0.2 vs 1.6±0.1, P<0.01 and 56.9 vs 23.3%, P<0.01 respectively). T2D patients on metformin presented a 25-fold increased risk of hyperlactacidemia (OR=25.10, P<0.05). Creatinine level was the only independent predictive factor for lactate increased concentrations (β=1.33, P<0.05). Patients with hyperlactacidemia had 4.4 higher odds of being hospitalized or die (OR=4.37, P<0.05).

Conclusions: T2D patients, particularly those under metformin, presented significantly higher serum lactate and prevalence of hyperlactacidemia. Creatinine level was the only independent predictive factor for lactate increased concentrations. Hyperlactacidemia implies a worse prognosis and must be discarded in T2D patients observed in ER.