Improved outcomes with linagliptin in patients with persistent prediabetes after metformin and lifestyle modifications.

This study evaluated the addition of linagliptin (Trajenta) to metformin (Glucophage) and lifestyle changes in patients with persistent prediabetes. The authors concluded that adding linagliptin after 12 months of metformin treatment and lifestyle changes improved glucose levels and pancreatic β-cell function in these patients. 

Prediabetes places patients at high risk of developing type 2 diabetes (T2D). Patients with prediabetes have impaired glucose tolerance (IGT). IGT is an abnormally high blood glucose level 2 hours after drinking water with glucose (oral glucose tolerance test; OGTT). 

Patients with prediabetes usually have a dysfunction of the β-cells of the pancreas that produce insulin. Insulin is the hormone that lowers glucose in the blood. In prediabetes, there is also a degree of insulin resistance (cells do not respond to insulin and glucose remains in the blood). Delaying or preventing prediabetes progression to T2D can be approached by lifestyle changes (diet and excercise) and metformin treatment. However, many patients still have high glucose levels after this treatment.

Linagliptin is a diabetes medication that works by increasing gut hormones called incretins. These gut hormones are naturally released after eating that help control blood glucose. It is not known if the addition of linagliptin to metformin and lifestyle changes in patients with prediabetes improves blood glucose and pancreatic cell function. 

This trial included 25 patients with prediabetes. All patients had been previously treated with 850 mg of metformin, twice daily along with lifestyle changes over 12 months. 15 patients were randomly assigned to receive linagliptin in addition to metformin (LM group). The other 10 patients continued to receive metformin and lifestyle changes (M group). Follow-up occurred every month for 6 months.

After 6 months, patients in the LM group had a reduction in body weight by 1.7 kg and a drop in blood pressure by 7.3 mmHg. The M group had a 2.4 kg increase in body weight and a 1.2 mmHg increase in the average blood pressure.

The LM group also had lower blood glucose levels after a OGTT compared to the M group. Blood glucose control over the past 2-3 months (measured through the HbA1c levels) was reduced by 0.2% in the LM group and increased by 0.3% in the M group.

Insulin sensitivity and pancreatic β-cell function were improved in the LM group, while they were slightly worse in the M group. 

The study showed that the addition of linagliptin to metformin and lifestyle changes improved the outcomes of patients with persistent prediabetes. 

This study had a very small number of participants.