A population-based study found no increased incidence of dementia in people with chronic obstructive pulmonary disease (COPD), but patients with COPD did have an increased risk of incident cognitive impairment. Findings from this study were published in Respiratory Medicine.
A team of UK researchers analyzed data for 62,148 patients with confirmed COPD (mean age, 66.4 years) recorded in the UK General Practice (GP) health records obtained from The Health Improvement Network database. Each patient was matched to up to 4 patients without a COPD diagnosis by age, sex, as well as GP practice (n=230,076; mean age, 65.7 years). The researchers used Cox proportional hazards models to evaluate the incidence rates of dementia and cognitive impairment in patients with vs without COPD.
A significantly greater proportion of patients with COPD developed cognitive impairment over the median follow-up period of 4.4 years compared with patients without COPD (9% vs 7%, respectively; P <.001). The incidence rates of cognitive impairment in patients with vs without COPD were 25.1 (95% CI, 24.3–25.6) and 17.6 per 1000 person-years (95% CI, 17.3–17.9), respectively.
In addition, the likelihood of having cognitive impairment after a COPD diagnosis was 22% compared with patients without COPD (adjusted hazard ratio [aHR], 1.21; 95% CI, 1.16─1.26; P <.001). An analysis adjusted for confounders found that the incidence of either cognitive impairment or dementia was significantly greater in patients with COPD (aHR, 1.13; 95% CI, 1.09─1.18; P <.001). There was no difference between patients with vs without COPD in regard to incident dementia (aHR, 0.91; 95% CI, 0.83─1.01; P =.053).
Limitations of this study included its retrospective nature as well as the researchers’ lack of adjustment for oxygen saturations and oxygen therapy.
The investigators concluded that these findings highlight “the potential likelihood of under-diagnosis of dementia with missed opportunity for proper intervention and underlining the need to accurately estimate the proportion of patients with COPD and dementia with a systematic assessment.”
Disclosure: Several study authors declared affiliations with the pharmaceutical industry. Please see the original reference for a full list of authors’ disclosures.
Siraj RA, McKeever TM, Gibson JE, Gordon AL, Bolton CE. Risk of incident dementia and cognitive impairment in patients with chronic obstructive pulmonary disease (COPD): A large UK population-based study.. Respir Med. Published online December 24, 2020. doi:10.1016/j.rmed.2020.106288