ABSTRACT
AIM: Prospective studies suggest that sleep-disordered breathing enhances the risk of diabetes. However, it remains unclear whether diabetes could worsen sleep-disordered breathing. METHODS: The participants from Sleep Heart Health Study underwent two polysomnograms at a 5-year interval. The relationship of baseline diabetes to change in the apnoea-hypopnoea index (AHI) was examined based on general linear models, adjusting for demographics, lifestyles, history of hypertension, pulmonary function, length of follow-up and baseline AHI. RESULTS: In total, 161 of the 2603 participants were diagnosed with diabetes at the first polysomnograms. Compared with participants without diabetes, those with diabetes had a higher baseline and larger increases in follow-up AHI and obstructive apnoea index (oAI). Diabetes increased 2.52 events per hour (95% confidence interval 0.45-4.59; p = .017) for AHI change and 1.13 events per hour (95% confidence interval 0.04-2.23; p = .042) for oAI change, respectively. In addition, subgroup analysis suggested that the association was consistent across baseline obstructive sleep apnoea severity and body mass index groups. CONCLUSIONS: Baseline diabetes was associated with worsening sleep-disordered breathing over 5 years, which mainly increased the change in AHI and oAI.
ABSTRACT
Chronic obstructive pulmonary disease (COPD) is commonly associated with type 2 diabetes mellitus (T2DM). Metformin is a first-line treatment for most patients with T2DM, and may have antiaging, antioxidant, and anti-tumour effects. A few published studies report the use of metformin for the treatment of COPD in patients with or without T2DM, but the results are inconsistent. This study aimed to confirm the effectiveness and safety of metformin as a treatment option in patients with COPD. We performed a systematic search of PubMed, EMBASE, and the Cochrane database from their starting date to December 2017. Randomised controlled trials (RCTs), controlled clinical trials, and retrospective researches reporting the use of metformin for treating patients with COPD were identified. We included a total of six articles (involving 3,467 participants) and found that metformin may benefit patients with COPD and T2DM by improving health status and symptoms, hospitalisations, and mortality. There was no effect on patients with COPD without T2DM. Metformin causes minimal increases in plasma lactate concentrations without lactic acidosis and has little impact on blood glucose and minor adverse events. Metformin is safe and effective for treating COPD in patients with concomitant T2DM.
