A Review of Insomnia Treatments for Patients with Mild Cognitive Impairment.

Katherine Pitcher,Meghan K Mattos,Angela Chang,Lee M Ritterband,Carley Whitt,Mark S Quigg

doi:10.14336/ad.2021.0423

Abstract

Mild cognitive impairment (MCI) impacts approximately 20% of older adults, with many also experiencing sleep disorders, such as insomnia. Given the relationship between sleep and dementia, addressing sleep issues may offer an opportunity to treat reversible causes. There are two primary treatments for insomnia: behavioral-based (cognitive behavioral therapy for insomnia, CBT-I) and pharmacological interventions. Although CBT-I is recommended as first-line treatment for insomnia in older adults, sedative-hypnotics are more likely to be recommended than non-pharmacological treatments given their convenience and accessibility. However, there are significant concerns in prescribing medications to patients with MCI. To explore this disconnect, we reviewed insomnia treatments in older adults with MCI studies and current guidelines of pharmacological therapy. First, we reviewed studies presenting non-pharmacological treatment of insomnia in older adults with MCI. Although the search yielded over 4,000 non-duplicate titles, only one article presented data on non-pharmacological treatment of insomnia in MCI. The literature covering comorbid insomnia, CBT-I, and MCI is sparse. In contrast to review of non-pharmacological studies, studies on the pharmacological treatment of insomnia in older adults were ample. Finally, we reviewed international guidelines for pharmacological treatment of insomnia in cognitive disorders. More widely used pharmacological interventions show short-term effectiveness with problems of recurrence, ineffectiveness in inadvertent or purposeful chronic use, and adverse side effects. Despite evidence regarding adverse consequences, pharmacological treatment of insomnia remains the most common treatment for insomnia. Reflecting on age-related changes in older adults, particularly those with MCI, inappropriate or mismanagement of medication can lead to unnecessary complications. Further research examining effective behavioral-based sleep management options in older adults with cognitive impairment is needed with exploration of improved sleep on cognitive function.

Highlights

Mild cognitive impairment (MCI, formerly “predementia”) is an important transitional state between normal cognition and dementias, such as Alzheimer’s disease (AD) [1, 2]
Because insomnia is common in individuals with MCI, the evaluation and treatment of insomnia present an opportunity to intervene in the early stages of cognitive decline in disorders that generally present with no known cure
Current guidelines [16,17,18,19,20] recommend nonpharmacological cognitive-behavioral therapy for insomnia (CBT-I) as the first step in insomnia treatment with pharmacological intervention only offered if the CBT-I was not effective or available [20]

Summary

Introduction

Mild cognitive impairment (MCI, formerly “predementia”) is an important transitional state between normal cognition and dementias, such as Alzheimer’s disease (AD) [1, 2]. Studies have shown that a lack of sleep likely contributes to the progression of AD [11] and may prevent interstitial fluid drainage through cerebrospinal fluid into interstitial space to clear beta-amyloid and phosphorylated tau from the brain [12, 13] This increased beta-amyloid production is even more concerning as insomnia symptoms are known to negatively impact the brain’s ability to clear these beta-amyloid plaques [6, 7]. Based on the current guidelines and complications of polypharmacy in older adults with cognitive concerns, our original intention was to review current non-pharmacologic therapies in older adults with MCI, namely CBT-I We found that these studies, quite do not yet exist in a quantity that makes sense for a review. Up to 50% of older adults report symptoms of insomnia that may or may not impact daytime functioning [21, 23]; chronic insomnia occurs in closer to 10-15% of the population [26, 27]

Findings

Discussion

Conclusion