People with the lung disease, COPD, may have an increased risk of experiencing cognitive impairment, including memory loss, a new study suggests.

COPD (chronic obstructive pulmonary disease) is an umbrella term for a number of chronic lung disorders, including bronchitis and emphysema. It is a progressive, disabling condition caused by a narrowing of the airways. Smoking is the main cause.

The disease currently affects around 440,000 people in Ireland and it is the world's fourth biggest killer.

US researchers followed the progress of around 2,000 people aged between 70 and 89. They found that people with COPD were twice as likely to experience mild cognitive impairment (MCI), and this risk increased the longer a person had the lung disease.

Incidence rates were similar among men and women.

The researchers explained that MCI is a stage between normal cognitive ageing and dementia. Those with MCI have an increased risk of going on to develop dementia, including Alzheimer's disease.

Because the risk of dementia increases with age and people are living longer today, identifying risk factors is essential, particularly as the management and treatment of dementia is limited.

"COPD is reversible in early stages, especially in smokers. These findings are important because they highlight the importance of COPD as a potential risk factor for MCI and will hopefully lead to early intervention to prevent incidence or progression," the researchers explained.

Details of these findings are published in the journal, Mayo Clinic Proceedings.

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