Observational studies have reported associations between low lung function and dementia risk but cannot test causality of this relationship. If causal, interventions to maintain lung function with ageing could reduce the burden of dementia. It is unclear how early in life the association between low lung function and cognitive impairment begins.
Observational studies have shown an association between asthma and multi-morbidity, especially psychological e.g. anxiety and depression. However this work has been carried out on small numbers of patients, and is purely cross-sectional. Using ALSPAC data we can do larger studies longitudinally gaining insight into how early these affects appear, how long they last and how severe. If we find a consistent association then we may be able to test for causality.