PURPOSE:
Metformin can reduce
diabetes-related complications and
mortality. However, its use is limited because of potential
lactic acidosis-associated
adverse effects, particularly in renal impairment
patients. We aimed to investigate the
association of
metformin use with
lactic acidosis and
hyperlactatemia in
patients with
type 2 diabetes. MATERIALS AND
METHODS:
This was a
cross-sectional study from a tertiary
university-affiliated medical center. A total of 1954
type 2 diabetes patients were recruited in 2007–2011, and stratified according to the estimated
glomerular filtration rate of 60 mL/min/1.73 m2.
Lactic acidosis was defined as
plasma lactate levels >5 mmol/L and arterial
pH <7.35.
RESULTS:
Metformin was used in 61.4% of the
patients with
type 2 diabetes mellitus.
Plasma lactate levels were not different in the
patients with and without
metformin use. There was no difference in
prevalence of
hyperlactatemia and
lactic acidosis between the
patients with and without
metformin use (18.9% vs. 18.7%, p=0.905 for
hyperlactatemia and 2.8% vs. 3.3%, p=0.544 for
lactic acidosis).
Similar results were observed in the
patients with estimated
glomerular filtration rate <60 mL/min/1.73 m². Most
patients with
lactic acidosis had at least one condition related to
hypoxia or poor
tissue perfusion. Multiple
regression analysis indicated no
association between
metformin use and
lactic acidosis, whereas
tissue hypoxia was an independent
risk factor for
lactic acidosis [
odds ratio 4.603 (95%
confidence interval, 1.327–15.965)].
CONCLUSION:
Metformin use was not associated with
hyperlactatemia or
lactic acidosis in
patients with
type 2 diabetes.