Integrative assessment of cerebral blood regulation in COPD patients

Cerebrovascular responses were compared between COPD and non-COPD participants. The association between COPD severity and cognitive function was also investigated. Cerebral blood velocity in the middle cerebral artery, blood pressure, and end-tidal CO₂ were recorded at rest, followed by a brain activation paradigm, and an inhaled gas mixture (5% CO₂) to assess cerebral autoregulation (CA), neurovascular coupling (NVC) and cerebrovascular reactivity to carbon dioxide (CVR_CO2), respectively. Pulmonary function, blood gas analysis (COPD) and cognitive function (MoCA test) were also performed. No difference in baseline (systemic and cerebral parameters) and CA was found between 20 severe COPD and 21 non-COPD. Reduced NVC and CVR_CO2 test were found in the COPD group. Lower pulmonary function was positively correlated with CA, NVC and CVR_CO2 in COPD patients. Cognitive impairment (MoCA<26) was associated with lower NVC responses (COPD and non-COPD) and lower pulmonary function (COPD). Both mechanisms, CVR_CO2 and NVC, were lower in COPD patients. Moreover, disease severity and cognitive impaired were associated with worse cerebrovascular regulation.