Cognitive Impairment and Brain Oxygenation in Chronic Obstructive Pulmonary Disease

Abstract

Objective: To explore the potential connection between cognitive deficiency and cerebral oxygenation in chronic
obstructive pulmonary disease sufferers and to examine potential links with their prevalent inflammatory, oxidative,
and vascular markers levels.
Study Design: Cross-sectional study
Place and Duration of Study: This study was conducted at the Tikrit Teaching Hospital, Iraq from 1st January to
31st December 2025.
Methods: This cross-sectional study was conducted at the Tikrit Teaching Hospital, Iraq from 1st January to 31st
December 2025 on a sample of 200 chronic obstructive pulmonary disease participants and 100 healthy volunteers
between the ages of 35-75 years. The chronic obstructive pulmonary disease group will include sociodemographic
information and clinical characteristics and some standard respiratory signs as forced expiratory volume in 1, forced

vital capacity, SpO2, and arterial blood gas, among other data. Cerebral oxygen saturation was measured by near-
infrared spectroscopy, and cognitive function was assessed by the Montreal Cognitive Assessment test.

Results: Chronic obstructive pulmonary disease patients had significantly lower mean rSO2 levels at 59.8±5.3%,
and worse Montreal cognitive assessment scores at 22.4±3.1 compared to the control group at 68.4±4.7% and
27.1±1.9, correspondingly. Inflammatory and oxidative markers C-reactive protein, interleukin-6, tumor necrosis
factor-α, elevated malondialdehyde were elevated in chronic obstructive pulmonary disease patients, and total
antioxidant capacity and brain-derived neurotrophic factor were reduced, all p<0.001. There was a strong positive
correlation between Montreal cognitive assessment scores and rSO2 at 0.68, SpO2 at 0.62, brain-derived
neurotrophic factor at 0.58, and negative with partial carbon monoxide pressure at -0.47 and C-reactive protein at -
0.51.
Conclusion: Since the neuromuscular oxygenation of chronic obstructive pulmonary disease is correlated with
markedly diminished cerebral oxygenation and systemic hypoxemia and various indicators of inflammation and
oxidative stress are increased while those of neurotrophic factors reduced, neuromuscular oxygenation and its
markers should be included for the measurement to enable early identification and treatment for these conditions.