Background

The consumption of caffeine has well known effects on the behavior and sleep of healthy adults. Behavioral symptoms and sleeping difficulties are common in patients with dementia which may be affected by caffeine consumption. This systematic review examines the association between caffeine intake and neuropsychiatric symptoms in patients with dementia.

Methods

In January 2019 an extensive search was conducted in Medline (PubMed), Embase, Emcare, Cochrane, PsychInfo, Web of Science and gray literature. Studies were included when they: i) investigated patients diagnosed with dementia, ii) reported neuropsychiatric symptoms, iii) used caffeine or coffee consumption as an intervention, and iv) reported associations between caffeine or coffee consumption and neuropsychiatric symptoms. Studies were excluded when they also included participants without a diagnosis of dementia, or presented a review or expert opinion. Two reviewers independently rated the studies and reached consensus on the appraisal.

Results

Of the seven studies eligible for this review, four reported on sleeping difficulties and five on behavioral symptoms. There was no consistent effect of caffeine administration on neuropsychiatric symptoms: e.g., both high caffeine consumption and eliminating caffeine were associated with less apathy, the total Neuropsychiatric Inventory (Nursing Home) decreased after both coffee therapy and after eliminating caffeine, and both caffeine consumption and eliminating caffeine improved sleep.

Conclusion

These findings suggest that caffeine can either induce or reduce neuropsychiatric symptoms in individual patients with dementia. Therefore, in these patients, caffeine consumption requires a prudent individualized approach and further research on the effects of caffeine on individual neuropsychiatric symptoms is required.

Copyright © 2019 Elsevier Inc. All rights reserved.