More evidence for harm of intensive diabetes treatment in older patients
medwireNews: Research shows an increased mortality risk associated with the use of intensive antidiabetes treatments in older patients with type 2 diabetes.
The data, obtained from 367 participants of the Fremantle Diabetes Study Phase II (FDS2) who were at least 75 years of age, show a 45% and 94% increased mortality risk for patients treated with sulfonylureas and insulin, respectively, compared with those receiving diet-based treatment.
Of note, there was also a significant 80% mortality risk increase for patients taking metformin. Researcher David Bruce (University of Western Australia, Fremantle) and team describe this as “unexpected given [metformin’s] safety profile and low risk of hypoglycaemia,” adding that “to our knowledge the impact of tight glycaemic control related to metformin has not been investigated in older people.”
They suggest this could be partly explained by doctors opting for metformin in the frailest patients, on the basis of its benign safety profile.
Metformin was used by 60.4% of patients, sulfonylureas by 35.3%, and insulin by 23.2%. The researchers note that use of newer medications was rare, given the study baseline of 2008–2011.
Within the three medication classes, the lowest risk for mortality occurred at a mid-range glycated hemoglobin (HbA1c) level, of 6.5–6.9% (48–52 mmol/mol) for metformin and 7.0–7.9% (53–63 mmol/mol) for sulfonylureas and insulin, with both higher and lower levels generally being associated with increased mortality risk.
“Whilst confounding by indication is likely to explain some of the medication-associated mortality in this study, within the treatment groups there were optimum HbA1c levels, above or below which it would appear to be worth changing treatment intensity and no survival advantage was seen with tight glycaemic control,” write the researchers in Diabetes, Obesity and Metabolism.
They note that hypoglycemia was “a potent candidate mechanism” underlying the mortality risk in patients taking sulfonylureas and insulin, especially “given the health status of our study population where hypoglycaemic risk factors were common.”
Bruce and team conclude: “These data are consistent with published concerns about the frequency of overtreatment in older people and strengthen calls to individualize glycaemic targets and pharmacotherapy in the older population.
“Studies of a deprescribing or represcribing policy are required in older people with type 2 diabetes to determine whether this results in improved survival and a reduced treatment burden.”
medwireNews is an independent medical news service provided by Springer Healthcare. © 2018 Springer Healthcare part of the Springer Nature group