Abstract
It has been suggested that sunbathing may increase the amplitude of the sleep-wake rhythm and nocturnal serum melatonin secretion, and have effects on insomnia as well. A case report of a patients with epilepsy, cerebral palsy, and severe mental and intellectual disabilities (SMID) with severe behavioral disturbance is presented, in which the sleep-wake-cycle (SWC) was markedly improved by a sunbathing for seven months. The schedule included a sunbathing for 30 minutes in the morning, and a walk with a sunbathing for 10~30 minutes in the afternoon. Reduction of frequency of excitement and pyrexia was also observed, and the latter effect persisted for more than six months after the completion of this schedule. In the present case, being similar to the effects of light therapy for insomnia in elderly persons, low level of nocturnal melatonin level exhibited a tendency toward normalization. These findings show that a sunbathing is an effective and simple method for the treatment of insomnia and behavioral disturbance associated with severe mental retardation. The effects of light therapy and / or a sunbathing on insomnia and serum melatonin level, particularly in individuals with brain damages, are reviewed based on the literatures.
Keywords: melatonin, light therapy, insomnia, mental retardation, sunbathing, dementia
Introduction
Patients with brain damages, e. g., those with certain types of mental retardation or dementia, frequently manifest behavioral disturbances, including insomnia, disturbance of sleep-wake cycle (SWC), wandering, excitement and hyperactivity. In addition to various types of pharmacotherapy, combinations of melatonin administration and / or light therapy, have been used to reduce these signs and symptoms [1-3].
In this review, a case report of a patient with severe mental and intellectual disabilities (SMID) with behavioural disturbance, epilepsy, and cerebral palsy is presented, in which the SWC was markedly improved by sunbathing for seven months [4]. In this case, a sunbathing was performed instead of light therapy, since the patient could neither understand the effects of light therapy nor remain in front of illumination equipment for long because of hyperactivity, and also tended to break the equipment. Sunbathing, which affects plasma melatonin level, and reinforcing social synchronizing factors as well as light synchronizing factors might comprise a simple and safe method for improving the SWC in patients with behavioural disturbance [5].
Case
The case is 39-year-old male with profound mental retardation, epilepsy (secondary generalized seizure), and cerebral palsy (incomplete right hemiplegia), i. e., SMID with severe behavioral disturbance.
Clinical History
Neonatal asphyxia occurred during a difficult delivery. He failed to develop communication skills, and manifested excitement with a loud voice, throwing of things, and violence towards others. Behavioural disturbance worsened as he developed. At 13 years of age, he was admitted to a special ward for SMID accompanied by severe behavioural disturbances. Though hypnotics were prescribed for insomnia following admission, he woke easily in response to even small sounds, shouted in a loud voice, and rapped on doors. When his excitement at night worsened, the doses of hypnotics were increased, but this proved ineffective. Instead, the following day, the risk of falling was increased because of unsteadiness. Assignment to a private room after each episode of excitement and walking with a nurse were ineffective in obtaining sedation. Repeated episodes of pyrexia (3-4 times per month) and phlegmon of the legs were observed.
EEG examination revealed a basic rhythm with poorly organized irregular a waves (8~12Hz, 20~30^V) intermingled with irregular slow waves in the left hemisphere, especially in the central region, and bilateral P waves. Multi-focal small spikes were frequently observed (right > left). Generalized 3 Hz spike-and-wave complexes appeared for 1 second, though their reproducibility was poor.
MRI demonstrated a small and thick skull. The left fronto-temporo-occipital and right parietal area contained vacuolar regions, indicating, old infarction. There was also lateral ventricular enlargement (left > right) and atrophy of the left ventral brainstem suggesting probable secondary change involving Wallerian degeneration of the corticospinal tract.
To improve insomnia, sunbathing was initiated. During this period, the same dosages of drugs (sodium valproate 1000mg, phenobarbital 100mg, levomepromazine 25 mg, diazepam 15mg, nitrazepam 5mg and flunitrazapam 1mg) were maintained.
Treatment Schedule
From April, 2007, sunbathing for 30 min in the morning and a walk with sunbathing for 10~30 min in the afternoon were performed. The latter was considered exercise. Walking was combined with sunbathing because the patient easily tired of staying in the same place for a long time. Exercise was performed for 10~30 min depending on the patient’s willingness to exercise and satisfaction.
The hospital was located at 39 degrees 24 min of North latitude. Illumination in the patient’s room was about 10000 Lx on sunny days and more than 3000 Lx on cloudy days from spring to autumn. A location with illumination above 2000 Lx was chosen for him to spend the daytime hours.
His SWC was checked from March, 2007, by observing sleep states and daytime activities to assess the effects of sunbathing. Serum levels of melatonin and cortisol were measured before, and 5 and 7 months after the beginning of the investigation to determine whether these levels were affected by sunbathing.
Quality of sleep and level of excitability were assessed according to standardized criteria, and compared with the same months of the previous year. Sleeping well was defined as sleeping until the morning with disturbed sleep limited to less than 30 min and waking no earlier than 4:00 in the morning. Excitement was defined as the existence of episodes for which isolation was required due to restlessness and excitement.
Results
On all the days when both sunbathing and exercise were performed, the patient slept well. The order of frequency of sleeping well in April to October, 2007 was as follows: sunbathing and exercise (100%, 22 days / 22 days) > sunbathing alone (87%, 27 / 31) > exercise alone (73%, 47 / 64) > neither treatment (62%, 26 / 42). In April to October, 2006 (the previous year), the frequency of sleeping well was lower for days with exercise alone (66%, 62 / 94) or neither treatment (55%, 55 / 92).
The frequency of excitement during the period of examination was lowest (4%, 1 / 21) on days when both sunbathing and exercise were performed. The frequency was 19% (6 / 31) on days with sunbathing alone, 23% (15 / 64) with exercise alone, and 26% (11 / 42) with neither treatment. In the previous year, the frequency of excitement was higher without sunbathing, i. e., 30% (28 / 94) with exercise alone and 43% (40 / 92) with neither treatment.
Since sunbathing and exercise were markedly effective for insomnia and behavioural disturbance, we terminated the examination at the end of October, 2007. The time course of sleeping well and excitement is shown in Figure 1. The SWC of the patient was remarkably improved as shown in Figure 2.
Figure 1. Relationship between frequencies of sleeping well and excitement during the period of sunbathing. Frequency of sleeping well increased while that of excitement decreased as sunbathing continued.
Figure 2. Sleep-wake-cycle. (a) Sleep log (based on nurses’ observation). A month before the start of sunbathing. (b) Sleep log. Six months after the start of sunbathing.
After the start of sunbathing and exercise, the frequencies of pyrexia and repetitive phlegmon of the legs, as well as epileptic seizures were reduced. From October, 2007, there were no episodes of pyrexia episode for more than 6 months [2].
Serum Levels of Melatonin and Cortisol
Before the investigation began (March 19, 2007), the serum melatonin level was low at 0:00 (9.5pg/mL). After 5 months (August 28, 2007), it had increased to 16 pg/mL, within the standard range (10-127 pg/mL [6]), and after 7 months (October 29, 2007), it remained 14 pg/mL, also within the standard range [6]. The serum melatonin levels at time 12:00 on March 19, August 28 and October 29 were consistently <2.8 pg/mL, the standard level (2.8—5.6 pg/mL [6]).
Serum cortisol level at time 0:00, though lower than the standard level (3.8—18.4 i g/dl; report from BML, Tokyo, Japan), increased during the investigation (levels on March 19, August 28 and October 28 were 2.6—2.9—3.41 g/dl). The level at 12:00 consistently remained in the standard range (11.8—^8.9—^11.6i g/dl).
Effect of Sunbathing
In the present case of SMID accompanied by behavioural disturbance, sunbathing appeared to be effective for the treatment of insomnia. Its effect included, i) improvement of the SWC; ii) reduction of the frequency of excitement; iii) reduction of the frequency of pyrexia, suggesting improvement of immune function; and iv) reduction of the frequency of epileptic seizures.
MRI findings demonstrated infarction of the cerebral cortex and atrophy of the brainstem, suggesting injury of the ascending reticular formation which plays roles in determining the SWC [7]. This was a possible cause of sleep disturbance in the present case. During the period of sunbathing, serum levels of melatonin, an endogenous sleep-inducer, and cortisol at time 0:00 tended to increase to normal levels, although sampling number and reproducibility were insufficient for definitive analysis.
Sunbathing, a simple and safe method, is thought to reinforce social synchronizing factors as well as light synchronizing factors [5]. In the present case, similar to the effect of light therapy for insomnia in elderly persons, low melatonin level exhibited a tendency toward normalization [3].
Generally, mentally retarded people typically exhibit poor sleep efficiency and reduced nocturnal plasma melatonin levels. This state is similar to that of the elderly, in whom decrease in amplitude of the sleep-wake rhythm and decreased levels of melatonin secretion are observed [4]. Exposure to bright light suppresses the production of melatonin, increases nocturnal melatonin secretion, and contributes to regulation of the circadian rhythm. The mechanism of elevation of nocturnal melatonin level in the present case remains to be explored.
Effects of Melatonin on Insomnia and Behavioural Disturbance
Mental Retardation
Several reports have described clinical trials of administration of exogenous melatonin to individuals with intellectual disabilities (ID) to improve insomnia and behavioural disturbance. Niederhofer et al. (2003) reported that oral administration of 0.1 or 3 mg melatonin, 30 minutes before bedtime, to mentally retarded subjects with sleep deficits facilitated sleep [8]. Dodd et al. (2008) reported that melatonin administration to three adults with moderate to severe ID changed circadian rhythm and improved challenging behaviour, though no significant effect was noted with regard to either quantity or quality of sleep [9]. Braam et al. (2008) reported that melatonin was, compared with placebo, effective for chronic insomnia in individuals with ID, including significant advance of mean sleep onset time and decrease in sleep latency [10]. Ishizaki et al. (1998) reported that melatonin at bedtime was efficacious in 42 of 50 patients with developmental disorders and sleep disorders (3-28 years of age; 41 males and 9 females; autism in 27 patients, mental retardation in 20 patients, and SMID in 3 patients), i. e., that excitability was often improved in patients with emotional / behavioural disturbance, whose sleep disorder was also improved, while stereotyped behavior and school/work refusal remained almost unchanged [11]. In these studies, the dosage of melatonin administered ranged from 2.5—6 mg per day [9-11].
In patients with severe behavioural disturbance, wrist actigraphy could not be performrd because the patients easily broke the device due to impaired mental function and behavioural problems. Sunbathing and / or phototherapy improves the SWC and reduces behavioural disturbance, possibly by increasing nocturnal melatonin secretion. Melatonin might be a key substance in improvement of the SWC and behavioural disturbance in cases of application of sunbathing and / or light therapy.
The Elderly and Persons with Dementia
In comparison with mental retardation, the insomnia of patients with dementia has been studied in greater detail. Mishima et al. reported that insufficient environmental illumination diminished melatonin secretion in the elderly [12], and that administration of artificial bright light and melatonin improved the circadian rhythm of institutionalized demented elderly persons [3]. It has also been reported that morning bright light reduced insomnia and behavioural disturbance including delirium [13].
There are numerous reports indicating that melatonin is effective for sleep disturbance in the elderly and patients with dementia [14-15], while, there is as yet insufficient evidence to conclude that melatonin improves cognitive function [15].
Conclusions
Sunbathing and / or phototherapy appears to be useful for treating insomnia in individuals with brain damage including certain types of mental retardation and dementia. Melatonin, insomnia, behavioural disturbance, and sunbathing should be further studied in larger numbers of patients with mental retardation, to obtain evidence for the effectiveness of sunbathing in treating insomnia and behavioural disturbance in the mentally retarded.
