Lactic acidosis rates in type 2 diabetes

Area of Science:

• Endocrinology and Metabolism
• Pharmacology and Therapeutics

Background:

• Metformin is a common medication for type 2 diabetes.
• Lactic acidosis is a rare but serious complication associated with metformin use.
• Understanding the baseline risk of lactic acidosis in type 2 diabetes patients is crucial for accurate risk assessment.

Purpose of the Study:

• To determine the incidence of lactic acidosis in patients with type 2 diabetes prior to metformin's approval in the U.S.
• To provide a baseline for interpreting the risk of lactic acidosis in metformin users.
• To investigate potential causes of lactic acidosis in this patient population.

Main Methods:

• Retrospective study using electronic health records from a large health maintenance organization.
• Identification of potential lactic acidosis events in type 2 diabetes patients.
• Confirmation and etiological analysis of events through review of clinical records.

Main Results:

• Over 41,000 person-years of data were analyzed.
• Four confirmed, three possible, and three borderline cases of lactic acidosis were identified.
• Severe co-existing medical conditions were identified as likely causes in all confirmed cases.

Conclusions:

• Lactic acidosis occurs infrequently in type 2 diabetes patients, with rates similar to those reported for metformin users.
• Severe medical conditions are potential causes for both metformin-associated and naturally occurring lactic acidosis.
• The observed association between metformin and lactic acidosis may be coincidental, warranting further investigation.