Sleep disturbances are commonly reported in patients with type 2 diabetes mellitus (T2DM), particularly those with symptoms suggestive of obstructive sleep apnea (OSA). An observational analysis published in Diabetology evaluated the association between metformin therapy and sleep architecture in patients with T2DM and OSA-related symptoms, including snoring and fatigue.

The analysis included polysomnography (PSG)-derived sleep stage data along with patient characteristics such as age, body mass index (BMI), and biological sex. Statistical evaluation was performed using t-tests and linear regression, with significance set at p<0.05. Among patients with BMI <30, metformin use was associated with a shorter duration of rapid eye movement (REM) sleep compared with alternative therapies (p=0.036). This difference was not observed in patients with BMI ≥30. Slow-wave sleep (N3) duration did not differ significantly between treatment groups. In patients not receiving metformin, age showed a moderate negative correlation with N3 duration (R²=0.4555).

No significant associations were identified between sleep stages and sex, smoking status, or higher BMI. These findings suggest that metformin use is associated with alterations in REM sleep among non-obese patients with T2DM and OSA symptoms. Further research is required to clarify the clinical implications of these observations.