Intensive glycemic control in adults aged 80 years and older: A randomized trial evaluating diabetes complications...

To evaluate whether intensive glycemic control reduces microvascular or macrovascular events compared with conservative glycemic targets in independently ambulatory adults aged 80 years or older with type 2 diabetes.

We conducted a prospective, randomized, open-label, single-center trial enrolling independently ambulatory adults aged ≥ 80 years with type 2 diabetes. Participants were assigned (1:1) to an intensive glycemic target (HbA1c < 7 %) or a conservative target (HbA1c < 9 %) and followed for 5 years. Primary outcomes were composite microvascular and macrovascular events. Analyses were done by intention to treat. Cause-specific Cox models and Fine-Gray subdistribution hazard models were used to account for all-cause mortality as a competing event. This trial is registered with ClinicalTrials.gov, NCT00850798.

206 participants were randomly assigned to intensive (n = 102) or conservative (n = 104) treatment. At 5 years, mean HbA1c was lower in the intensive group than in the conservative group (7·42 % vs 8·21 %; p = 0·005). Intensive therapy did not reduce microvascular events (hazard ratio [HR] 1·24, 95 % CI 0·76-2·04) or macrovascular events (HR 1·02, 0·36-2·92). Competing risk analyses showed no reduction in cumulative incidence of vascular outcomes (subdistribution HR approximately 1·0 for both). The cumulative incidence of death exceeded that of vascular events, indicating that many participants died before potential glycemic benefits could be realized. Severe hypoglycemia requiring hospitalization was more frequent with intensive therapy (7 vs 1 event).

In adults aged 80 years or older with type 2 diabetes, intensive glycaemic control improved glycaemic levels but did not reduce vascular events and increased the risk of severe hypoglycaemia. High competing mortality substantially limits the potential long-term benefit of intensive treatment, supporting conservative and individualized glycemic targets in very old adults.

ClinicalTrials.gov Identifier: NCT00850798.