Contraindications to metformin therapy in patients with Type 2 diabetes—a population‐based study of adherence to prescribing guidelines

Abstract

This population-based study shows that 24.5% of patients prescribed metformin have contraindications to its use. Development of contraindications rarely results in discontinuation of metformin therapy. Despite this, lactic acidosis remains rare. Diabet. Med. 18, 483-488 (2001)

Metformin revisited: A critical review of the benefit–risk balance in at-risk patients with type 2 diabetes

“…Indeed, a population-based study shows that almost a quarter of patients prescribed metformin have contraindications to its use. Furthermore, development of contraindications rarely results in discontinuation of metformin therapy [16]. These data have been confirmed in several other studies in various countries [17,18].…”

“…In contrast to what has been reported for other glucose-lowering agents, especially the new incretin-based therapies, no specific trials have been performed assessing the benefit-risk balance of metformin use in patients with moderate or severe RI [51]. In the various series reporting real-life data, patients receiving metformin despite the presence of RI as official contraindication are not rare, apparently without any harm [16][17][18]. In the fourth National Health and Nutrition Examination Survey (NHANES IV), the proportion of patients using metformin progressively decreases according to the severity of RI, from 45.6 % at stage 1 to 23.8 at stage 3 and 0 % at stages 4 and 5 [52].…”

“…In patients without comorbid conditions that would predispose them to lactic acidosis, elevated serum creatinine levels (or reduced GFR) should be considered a risk factor for the development of lactic acidosis but not an absolute contraindication [84]. In daily clinical practice, development of contraindications, including RI, rarely results in discontinuation of metformin therapy and, despite this, lactic acidosis remains a rare event [16,85]. In some studies, the prevalence of T2DM receiving metformin despite having a contraindication (including a GFR < 60 mL/min) was over 80%.…”

Contraindications can damage your health—is metformin a case in point?

“…Moreover, both retrospective population-based studies [12] and studies in selected cohorts [10,11,13,14,35,36] showed that the currently proclaimed contraindications and precautions for metformin therapy are frequently disregarded (Table 2). Interestingly, among the ∼2,500 patients followed in these studies only one case of lactic acidosis was reported, and even this one case could not be causally attributed to metformin since it was associated with intercurrent myocardial infarction and renal failure [12].…”

“…The first is that some patients do not tolerate it well, and the second is that traditional contraindications limit its use [5][6][7][8][9]. Although such contraindications are frequently overlooked in clinical practice, an increased incidence of serious side-effectsparticularly lactic acidosis-has not been observed [10][11][12][13][14]. This raises the question whether the contraindications, as currently outlined, deprive many patients with type 2 diabetes of the benefits of metformin.…”