Sleep disturbances, including reduced nocturnal sleep time, sleep fragmentation and parasomnias are common clinical problems in dementia. It has been reported that they affect 25–35% of individuals with Alzheimer’s disease (AD).1 This has been shown to result in significant amounts of patient and carer distress. Sleep disorders cannot always be managed by sleep hygiene methods alone, so medical treatment is often sought. However, there is significant uncertainty about the efficacy and side effects of the various hypnotic medications, especially in this vulnerable population.

Insomnia
The causes of insomnia are complex and multifactorial, and can often be put down to both physical and psychiatric comorbidities, especially in the elderly population. Insomnia can either be ‘primary’ where there is no identifiable cause for insomnia or ‘secondary’ where there is another condition including a physical, pharmacological or physiological cause contributing to the sleep disturbance. Primary insomnia is therefore a diagnosis of exclusion and if investigated, only counts for 12–30% of chronic insomnia, and could be even lower in an elderly population. 

Drug treatment and its efficacy
Drug treatment is frequently used in sleep disorders in patients with dementia. A number of hypnotic agents are licensed for treatment: including the benzodiazepines; zaleplon, zolpidem and zopiclone (Z-drugs). However medication such as neuroleptics, antidepressants, anticonvulsants and beta blockers are also occasionally used. With the increasing usage of hypnotics in care homes, and the consequences of sleep problems cause in people with dementia, we must be sure that we are using the correct pathways of treatment. We must be clear that the benefit of medically treating patients will outweigh risk. 

Hypnotics, such as zopiclone, have been proven to increase the risk of falls, yield a quick development of dependence, tolerance, and may also cause subsequent withdrawal.2 These concerns led the Committee on Safety of Medicines to recommend the use of benzodiazepines should be restricted to the treatment of severe insomnia. Additionally treatment should be at the lowest possible dose and not be continued beyond four weeks.3 This can be done by stating a stop date on the drug chart to force a prescriber’s review. Furthermore, the Medicines and Healthcare products Regulatory Agency (MHRA) has re-classified zopiclone and zaleplon as class C drugs from the 10th June 2014, and they will be prescribed similarly to controlled drugs such as morphine.4  

Parasomnias
Another important consideration is that night terrors, visual hallucinations and sleep walking are common symptoms of parasomnia, a condition this is closely associated to Parkinson/Lewy body dementia. At its most severe this has been linked to aggression and murder in old age: dramatic reports of homicide still gain considerable attention in the media.5
Research has shown that hypnotics are usually ineffective for parasomnias, yielding the need for a different treatment pathway. In these cases, consideration should be given to gradually withdrawing anti-Parkinsonian medication that might have triggered parasomnias in people with Parkinson’s. Similarly mirtazapine and centrally acting beta-blockers can promote parasomnias.6 The National Sleep Disorders Research plan suggests that clonazepam 500mcg can be used, but the evidence of any other treatment for this condition is limited.7
Parasominas have been defined as: ‘undesirable motor or sensory experiences that occur during entry to sleep, within sleep or during arousal from sleep.’ They range from simple imagery at sleep onset to complex and coordinated motor activity such as running and punching.

Pharmacotherapies for sleep disturbances
A recent paper reviewed the available pharmacotherapies for sleep disturbances in AD. The paper aimed to identify and appraise evidence from randomised controlled trails of different drug treatments in patients with dementia, and identify both short and long-term benefits and risks of medical treatment. Their results looked at patients with night time behaviours that were associated with disturbance or distress to both patient and care-giver. They found that low dose trazodone (50mg) significantly improved total nocturnal sleep time and sleep efficiency with AD and disturbed sleep. 

It was also shown that melatonin has neither beneficial nor harmful effects on sleep in patients with dementia.8 The paper concluded that there was only limited primary evidence, so until more evidence develops all pharmacotherapies for sleep disturbance should be used with caution.  

Who are we treating?
Sleeplessness can result in a significant amount of distress to both patient and carer. Many caregivers cite sleep disturbances, including night wandering and confusion, as the reason for institutionalising the elderly. However in care homes especially, it is important that the distress of the patients themselves is what is being treated, not the distress of the staff. 

Sleep hygiene

  • Think comorbidity—is it causing insomnia eg. breathlessness due to congestive cardiac failure or nocturia due to benign prostatic hyperplasia
  • Increase day-time simulation
  • Minimise daytime napping
  • Encourage routine
  • Reduce caffeine
  • Regular toileting
  • Keep the bedroom quiet, dark and a comfortable temperature 
  • Avoid going to bed hungry or too full
  • Get regular exposure to natural light.

Conclusion
In conclusion, sleep disturbances in dementia are common and can be distressing. They are often caused by physical illness, iatrogenic causes or parasomnias. It is important that these causes are investigated and treated accordingly. Medical treatment is frequently used when insomnia cannot be treated by sleep hygiene alone. However, there is considerable uncertainty about the balance of benefits and risks associated with treatment. Therefore, pharmacological intervention should be used with caution and be restricted to severe cases. The supply should be limited to pulses of treatment, with a stop date on the prescription. Medication should be used following the guidelines available and Cochrane hints at trazodone 50mg having the best evidence base. Finally, treatment should be used for the right reasons; treating the patient’s distress not that of their carers. 

 

Conflict of interest: none declared
References


1. Dauvilliers Y. Insomnia in patients with neurodegenerative conditions. Sleep Medicine 2007; 4: 27–34
2. NICE. http://www.nice.org.uk/guidance/ta77/documents/nice-issues-guidance-on-the-use-of-drugs-for-the-management-of-insomnia-. (accessed 10/11/14)
3. NICE. http://www.nice.org.uk/nicemedia/pdf/TA077fullguidance.pdf (accessed 10/11/14)
4. Home Office Circular 008/2014: http://www.mhra.gov.uk/Howweregulate/Medicines/Medicinesregulatorynews/CON421308 (accessed 10/11/14)
5. Broughton et al. Homicidal Somnambulism: A Case Report. Sleep 1994; 17(3)
6. NICE. https://www.nice.org.uk/guidance/cg35 (accessed 10/11/14)
7. Uddin ABMS, et al, REM Sleep Behavior Disorder, August 2009 eMedicine. http://emedicine.medscape.com/article/287104-overview (accessed 10/11/14)
8. McCleery J1, et al. ‘Pharmacotherapies for sleep disturbances in Alzheimer’s disease’. Cochrane Database of Systematic Reviews 2014, Issue 3