Cognitive impairment and its effect on chronic obstructive pulmonary disease: An underestimated phenomenon

Abstract

Background: To assess the ability of the Rowland Universal Dementia Assessment Scale (RUDAS) to predict inhaler technique and determine the prevalence of cognitive impairment in chronic obstructive pulmonary disease (COPD). Patients and Methods: This cross-sectional study included 98 participants, and we recorded age, education, locality, occupation, COPD stage, comorbidities, duration of inhaler use, and smoking history. Inhaler technique was assessed using an internationally accepted schedule (nine steps). RUDAS, a multicultural cognitive assessment scale, was used to assess cognitive function. Results: The study included 92 males and 6 females with the mean age of 63.9 years. At a cutoff of 24, RUDAS had 93.6% sensitivity and 88.2% specificity in screening incorrect inhaler technique. Those having a RUDAS score <24 were 272 times more likely to perform incorrect inhaler technique. On comparison of incorrect and correct inhaler technique groups on various parameters in univariate analysis, it was found that the groups were significantly different in terms of education, locality, occupation, COPD stage, comorbidities, and smoking history. However, in logistic regression, only RUDAS score <24 was found to be a predictor of incorrect inhaler technique. At the original cutoff of 23, RUDAS screened 42.9% (n = 42) of the patients as having cognitive impairment. Conclusions: High prevalence of cognitive impairment among COPD patients and its untoward impact on inhaler technique is an important but underestimated clinical issue. RUDAS is an effective tool to predict incorrect inhaler technique and cognitive impairment in COPD.

Keywords

• chronic obstructive pulmonary disease
• cognitive impairment
• inhaler technique