Impact of cognitive impairment on asthma control in older asthmatics

Purpose: Assessment of the severity and clinical course of asthma is important for effective disease control. Cognitive and physical impairments occur due to the aging process, which may impact on asthma control. We aimed to evaluate the impact of cognitive function on the assessment of asthma control in older asthmatics as a prospective interventional trial. Methods: A total of 50 mild to moderate asthmatics over 60 years of age were enrolled. Three questionnaires were used: the asthma control test (ACT), the asthma-specific quality of life, and the Korean version of the Short Form of the Geriatric Depression Scale. The Seoul neuropsychological screening battery-dementia version (SNSB-D), Korean version of the Mini-Mental Status Examination, and the Seoul instrumental activities of daily living scale were applied for neuropsychological assessment. Results: The mean patient age was 67.0 +/- 4.9 years, and 30 patients (60.0%) were female. The sensitivity and specificity of the ACT for determining well-controlled asthma were 91.7% and 39.5%, respectively. Regarding neuropsychological assessment, 22 patients (44%) had mild cognitive impairment, 4 (8.7%) had dementia, and 17 (34%) had depression. Total SNSB-D score was significantly higher in patients with an ACT score of >= 20 (P=0.015). The ACT scores were significantly associated with SNSB-D results in analyses adjusted for age, sex, education duration, lung function, and depression (P=0.004). Conclusion: We found significant positive correlations between cognitive functions, as measured by SNSB-D, and asthma control status, as measured by ACT scores, in older patients with asthma. Therefore, cognitive impairment may be associated with poor asthma control in older asthmatics.