Cognitive impairment in chronic respiratory disease patients using long-term oxygen therapy: a narrative review

Long-term oxygen therapy is used to treat of chronic respiratory diseases with chronic hypoxia. To date, long-term oxygen therapy has significantly contributed to the relief of dyspnea in the daily life of patients with chronic respiratory disease and chronic hypoxemia. Chronic hypoxia is a possible cause of cognitive impairment, and patients with chronic respiratory disease using long-term oxygen therapy with severe chronic hypoxia may be at a higher risk of cognitive impairment than patients using non-long-term oxygen therapy. Cognitive impairment in patients with chronic respiratory disease can lead to a decline in treatment adherence, including medication usage, health care check-ups, and smoking cessation efforts, which contribute to disease progression. In addition, patients using long-term oxygen therapy require oxygen delivery equipment. Operating oxygen delivery equipment is difficult for patients with cognitive impairment, and the inability to use long-term oxygen therapy properly is a serious challenge that can affect their life expectancy. Patients with chronic respiratory disease who use long-term oxygen therapy may be more affected by cognitive impairment than non-long-term oxygen therapy patients. Several review articles have addressed cognitive impairment in patients with chronic respiratory disease; however, none specifically focus on patients with chronic respiratory disease using long-term oxygen therapy. This narrative review describes the current knowledge and future issues regarding cognitive impairment in patients with chronic respiratory disease using the long-term oxygen therapy.