Self-reported sleep disturbance and mild cognitive impairment in COPD patients with severe airflow limitation

COPD has multiple extrapulmonary manifestations and the latest studies have focused on cognitive dysfunction effects on sleep quality. The purpose of this study is to assess if there is a relationship between sleep quality and cognitive decline in COPD patients with severe airflow limitation.

We performed an observational study to determine if there is a link between cognitive function and sleep quality. The included patients were divided into two groups: a group with COPD patients and control group. We evaluated lung volumes, cognitive function, sleep quality and disease impact on the quality of life.

Most of the COPD patients presented mild cognitive impairment (MCI) (95.7%), compared with only 24.1% in the control group (Pearson chi-square χ² (1) = 42.560, p < 0.001). We observed that all the COPD patients were poor sleepers, while only 13.8% of the control patients presented a poor sleep (Pearson chi-square χ² (1) = 60.379, p < 0.001). We observed that poor sleep was significantly associated with MCI (OR = 9.200; 95% CI = 3.656-23.153; p < 0.001). At the same time, when considering only the COPD patients with moderate disease impact, poor sleep was also a risk factor for MCI (OR = 1.210; 95% CI = 1.016-1.440; p < 0.001).

COPD patients with severe airflow limitation report a high prevalence of poor sleep quality and cognitive function. We observed a significant association between cognitive function and sleep quality.