Alterations of the default mode network and cognitive impairments in patients with chronic obstructive pulmonary disease

Abstract

Background and objectives

Cognitive impairment is a common extrapulmonary comorbidity in COPD patients. The default mode network (DMN) plays a critical role in maintaining the normal activities of humans, and its function can be evaluated by resting state functional magnetic resonance imaging. The aim of this study was to investigate the correlations between cognition and function changes of the DMN in COPD patients.

Methods

One hundred and thirteen eligible participants including 30 control subjects and 83 COPD patients matched for demographic characteristics were recruited. All participants performed cognitive function tests and underwent resting state functional magnetic resonance imaging.

Results

The total cognitive function scores of COPD patients were significantly different from those of control subjects (P<0.05) and worsened with the degree of airflow obstruction. The activated brain regions in the DMN of COPD patients were less than those of normal controls. Six activated brain regions in the DMN were found to develop significantly different functional connectivity (FC) values among the subjects. Meanwhile, the FC values of the left posterior cingulate cortex and left hippocampus correlated well with cognitive functions and pulmonary function.

Conclusion

COPD patients have cognitive impairments that correlate well with disease severity. FC changes in activated brain regions in the DMN may predict cognitive impairment, and the left posterior cingulate cortex and left hippocampus may be important brain regions related to cognitive impairment in COPD patients.

Keywords:

• chronic obstructive pulmonary disease
• cognitive function
• resting state functional magnetic resonance imaging
• default mode network

Acknowledgments

The authors would like to sincerely thank the Pulmonary Department, Magnetic Resonance Imaging Department, and Physical Examination Center, First Affiliated Hospital of Anhui Medical University for assistance with recruitment and clinical assessment of participants. The authors also thank professor Jia-Hu Hao in Anhui Medical University for verifying the data analysis. This work was supported by the National Science Foundation of China (numbers 81270081 and 81570034).

Author contributions

XW Hu carried out the experiment and performed the statistical analysis. YH Tu collected the clinical information. MM Yin and HB Wang carried out the rs-fMRI scan and image processing. All authors participated in the conception and design of the experiment, contributed toward data analysis, drafting and critically revising the paper, gave final approval of the version to be published, and agree to be accountable for all aspects of the work.

Disclosure

The authors report no conflicts of interest in this work.