Jennifer Martin

Effect of Light Treatment on Sleep and Circadian Rhythms in Demented Nursing Home Patients

OBJECTIVESnTo determine whether fragmented sleep in nursing home patients would improve with increased exposure to bright light.nnnDESIGNnRandomized controlled trial.nnnSETTINGnTwo San Diego-area nursing homes.nnnPARTICIPANTSnSeventy-seven (58 women, 19 men) nursing home residents participated. Mean age +/- standard deviation was 85.7 +/- 7.3 (range 60-100) and mean Mini-Mental State Examination was 12.8 +/- 8.8 (range 0-30).nnnINTERVENTIONSnParticipants were assigned to one of four treatments: evening bright light, morning bright light, daytime sleep restriction, or evening dim red light.nnnMEASUREMENTSnImprovement in nighttime sleep quality, daytime alertness, and circadian activity rhythm parameters.nnnRESULTSnThere were no improvements in nighttime sleep or daytime alertness in any of the treatment groups. Morning bright light delayed the peak of the activity rhythm (acrophase) and increased the mean activity level (mesor). In addition, subjects in the morning bright light group had improved activity rhythmicity during the 10 days of treatment.nnnCONCLUSIONnIncreasing exposure to morning bright light delayed the acrophase of the activity rhythm and made the circadian rhythm more robust. These changes have the potential to be clinically beneficial because it may be easier to provide nursing care to patients whose circadian activity patterns are more socially acceptable.

Illumination levels in nursing home patients: effects on sleep and activity rhythms

Studies examining levels of illumination in adult populations have demonstrated that the level and amount of light exposure are lower in the elderly compared with younger adults, particularly in institutionalized patients with dementia. Although insufficient light exposure has been implied as a cause of sleep fragmentation, evidence for such a relationship is scant. Sixty‐six institutionalized elderly had their activity and light exposure monitored for a 3‐day period. Mean and median light levels, minutes spent over 1000 and over 2000u2003lux, percent sleep and wake, and number of naps were computed for daytime intervals, defined as 07.00–18.59. Percentages of sleep and wake, number of awakenings and mean duration of wake periods were computed for night‐time intervals, defined as 22.00–05.59. Mesor, amplitude and acrophase of activity and of light were determined by cosinor analysis. A mixed linear model was used to assess the effects of daytime Actillume measures on subsequent night‐time measures, and vice versa. Spearman correlations were computed, and multiple regression analyses were carried out with light variables and dementia level as predictors and sleep–wake and activity measures as dependent variables. The median light level was 54u2003lux and a median of only 10.5u2003min were spent over 1000u2003lux. Higher light levels predicted fewer night‐time awakenings, and severe dementia predicted more daytime sleep and lower mean activity. Increased bright light exposure predicted later activity acrophase. There was an association between the acrophases of light and of activity, with maximum illumination preceding peak activity. These results suggest that daytime light exposure has an impact on both night‐time sleep consolidation and timing of peak activity level.

CIRCADIAN RHYTHMS OF AGITATION IN INSTITUTIONALIZED PATIENTS WITH ALZHEIMER'S DISEASE

Agitation is a common problem in institutionalized patientswith Alzheimers disease (AD). “Sundowning,” or agitationthat occurs primarily in the evening, is estimated to occur in 10—25%of nursing home patients. The current study examined circadian patterns ofagitation in 85 patients with AD living in nursing homes in the San Diego,California, area. Agitation was assessed using behavioral ratings collectedevery 15 minutes over 3 days, and activity and light exposure data were collectedcontinuously using Actillume recorders. A five-parameter extension of thetraditional cosine function was used to describe the circadian rhythms. Themean acrophase for agitation was 14:38, although there was considerable variabilityin the agitation rhythms displayed by the patients. Agitation rhythms weremore robust than activity rhythms. Surprisingly, only 2 patients (2.4%) were“sundowners.”In general, patients were exposed to very low levelsof illumination, with higher illumination during the night being associatedwith less robust agitation rhythms with higher rhythm minima (i.e., some agitationpresent throughout the day and night). Seasonality was examined; however,there were no consistent seasonal patterns found. This is the largest studyto date to examine agitation rhythms using behavioral observations over multiple24h periods. The results suggest that, although sundowning is uncommon, agitationappears to have a strong circadian component in most patients that is relatedto light exposure, sleep, and medication use. Further research into the understandingof agitation rhythms is needed to examine the potential effects of interventionstargeting sleep and circadian rhythms. (ChronobiologyInternational, 17(3), 405–418, 2000)

Effect of Light on Agitation in Institutionalized Patients With Severe Alzheimer Disease

OBJECTIVEnPreliminary data suggest that morning bright light might improve symptoms of agitation, a serious problem in patients with dementia. The authors expand on an earlier pilot study by evaluating the effect of bright light therapy on agitated behavior in a large sample of patients with severe dementia.nnnMETHODSnNinety-two patients were randomly assigned to morning bright light, morning dim red light, or evening bright light. Agitation was rated by research staff who observed the patients every 15 minutes throughout the treatment period and by caregivers at one time-point before and one time-point after treatment.nnnRESULTSnMorning bright light delayed the acrophase of the agitation rhythm by over 1.5 hours. Bright light was associated with improved caregivers ratings but had little effect on observational ratings of agitation.nnnCONCLUSIONnAlthough the result that light shifted the peak of the agitated behavior might be generalizable to patients with milder forms of AD, the fact that agitation was not ameliorated might not be. Because the suprachiasmatic nucleus (SCN) of patients with severe AD is likely to be more degenerated, and the circadian activity rhythms deteriorate as the disease progresses, it is still possible that patients with more intact SCNs, that is, patients with mild or moderate AD, might benefit from light treatment even more than those with severe AD.

Sleep-disordered breathing and agitation in institutionalized adults with Alzheimer disease.

OBJECTIVEnThe authors examined the relationship between sleep-disordered breathing (SDB) and agitation in patients with Alzheimer disease (AD).nnnMETHODSnThirty-eight AD patients (29 women, 9 men) in nursing homes in San Diego, CA participated. The mean age was 82.3 years, with a range of 61 to 95 years. Mean Mini-Mental State Exam score was 6.5 (range: 0-16). Sleep was recorded for one night, and agitation was measured with behavioral observations and ratings by nursing staff.nnnRESULTSnSDB was very prevalent in this sample and was related to some types of agitation during the day but not in the evening or night. Aggressive Agitation on the Cohen-Mansfield Agitation Inventory and Manual Manipulation on the Agitated Behavior Rating Scale were greater with more severe SDB. Searching and wandering agitation decreased with more severe SDB.nnnCONCLUSIONnThis study supports the hypothesis that SDB is related to agitation in AD, although the results are specific to certain types of agitation. Treatment of SDB may decrease agitation, easing the burden of caregiving and prolonging the time that patients are able to remain at home.

Identification and treatment of sleep problems in the elderly

For many adults, changes in sleep occur with aging. An estimated 15 million elderly, or 50% of older Americans, experience some sleep problem. The elderly complain that their sleep is more fragmented and that as they have gotten older, they experience more daytime sleepiness. Laboratory studies have confirmed these complaints. Research has shown that it is not the need for sleep that decreases with age, but rather the ability to sleep. Circadian rhythm disturbances, sleep disorders such as sleep disordered breathing and periodic movements in sleep, medical illness, medication use, and impaired cognitive functioning all contribute to poor sleep and decreased daytime alertness. In institutionalized elderly, sleep is even more disturbed and disrupted. With careful assessment, many of these problems can be addressed and treated, and sometimes cured.

Assessment and treatment of sleep disturbances in older adults.

Sleep disturbances are common in older adults. These disturbances are often secondary to medical illness and/or medication use or are due to specific problems such as sleep disordered breathing, periodic limb movements in sleep and circadian rhythm disturbances. The prevalence of sleep disordered breathing and periodic limb movement in sleep increases with age. The circadian rhythm tends to advance with age, causing older people to awaken early in the morning. Insomnia is often caused by pain associated with medical illness. Insomnia can also be caused by stimulating medications. In institutionalized elderly, sleep becomes even more disturbed and fragmented than in community-dwelling older adults. Accurate assessment and diagnosis is crucial since effective treatment strategies are available for these sleep disturbances. The effect, prevalence and treatment of each of these conditions is reviewed.

Sleep-disordered breathing and periodic limb movements in sleep in older patients with schizophrenia

BACKGROUNDnSince the prevalence of both sleep-disordered breathing (SDB) and periodic limb movements in sleep (PLMS) increase with age, we explored whether older schizophrenia patients would have a high incidence of SDB and PLMS. Correlations between sleep and clinical variables were also examined.nnnMETHODSnFifty-two patients (mean age = 59.6 years, SD = 8.9) had their sleep/wake, respiration, and leg movements recorded using a modified Medilog/Respitrace portable recording system plus oximetry. A battery of clinical, psychosocial, and motor disturbance variables were collected by research center staff.nnnRESULTSnForty-eight percent of these patients had at least 10 respiratory events per hour of sleep. These patients reported more symptoms of daytime sleepiness than patients with fewer than 10 events per hour. The relatively high prevalence of SDB in this group may contribute to overall sleep disturbances, and does not appear to be a result of high body mass index. Only 14% of the patients had at least five limb movements per hour of sleep, suggesting the prevalence of PLMS is much lower than expected in this age group. The number of leg jerks was inversely related to symptoms of tardive dyskinesia.nnnCONCLUSIONSnThe disturbance of sleep in these patients may be due, in part, to SDB, but is unlikely due to PLMS.

Actigraphic estimates of circadian rhythms and sleep/wake in older schizophrenia patients

Twenty-four hour circadian activity rhythms and light-exposure levels of 28 older schizophrenia patients (mean age=58years) were examined using an Actillume recorder. Sleep and wake were scored using the algorithm of the ACTION3 software which revealed that the patients slept for 67% of the night and napped for 9% of the day. Patients with more disturbed sleep and less robust circadian rhythms performed more poorly on neuropsychological tests. Patients with higher cognitive functioning and fewer extrapyramidal symptoms were more alert during the day. Few patients were exposed to high levels of illumination during the day, and older age was associated with lower levels of light exposure. Duration of antipsychotic use and higher antipsychotic doses were associated with decreased daytime alertness and less robust circadian activity rhythms. Patients taking antipsychotics were more sleepy both during the day and night than patients not taking antipsychotics. The circadian rhythm disturbances found in these patients did not seem to be due solely to low levels of illumination exposure. Life-style factors, behavioral factors, psychiatric symptoms and medications were likely contributors to the disturbed rhythms. The effects of the sleep disturbances did not seem to be benign. There were strong relationships between sleep and circadian rhythms and functioning.

Light Exposure and Quality of Life in Older Schizophrenia and Schizoaffective Disorder Patients

It is well known that patients with psychiatric disorders complain of sleep difficulties and, in fact, these complaints are confirmed by objective studies.1 Patients with schizophrenia and patients with mood disorders tend to have extremely disturbed sleep and complain of excessive daytime sleepiness, insomnia, or both. There is some evidence that patients with schizophrenia may have circadian rhythm disturbances and/or blunted circadian sleep/wake patterns.2-4 It is known that light exposure is a strong synchronizer of the sleep/wake system and that exposure to bright light tends to decrease with advancing age5 In addition to its direct effect on the circadian system, light exposure has also been implicated as a treatment for some mood disorders.