Table 1.

Summary of Clinical Studies of Light Therapy for Sleep and Circadian Rhythm Disorders in Older Persons

Study	Design	Treatment					Control Procedure	Sleep or Circadian Rhythm Measure(s)c	Major Findingsa
		Population (n; mean age; depression; circadian disorder; institutional setting; dementia)	Intensity (lux); Duration (hours)	Spectrum	Timing	Adjunct treatment
Alessi et al., 200544	Randomized, controlled, parallel-groups trial	62; 88; N; Y; Y; N	≥10,00; 0.5	Sunlight	Generally in morning	Exercise, nighttime routine, noise reduction	Usual care	Actigraphy, oximetry, observations	Reduction in nighttime awakening duration and daytime sleeping in treatment group.* No other differences between groups.
Ancoli-Israel et al., 200225	Randomized, controlled, parallel-groups trial	77; 86; N; N; Y; Y	2,500; 2	White	9:30–11:30am or 5:30–7:30pm	-	50 lux red light or daytime sleep restriction	Actigraphy	Phase delay and increased mesor in morning light treatment group.* Phase delay in evening light treatment group. No other differences between groups.
Ancoli-Israel et al., 200345	Randomized, controlled parallel-groups trial	61; 82; N; N; Y; Y	2,500; 2	‘Full spectrum’	9:30–11:30 am or 5:30–7:30pm	-	<300 lux red light	Actigraphy	Increase in maximum sleep bout duration in both treatment groups. No other differences between groups.
Colenda et al., 199746	Pre-post trial	5; 76; -; Y; N; Y	2,000; 2	White	Upon awakening – between 7am and 9:30am	-	-	Actigraphy	No consistent effects across subjects.
Dowling et al., 200547	Randomized, controlled, parallel groups trial	70; 84; -; Y; Y; Y	≥2,500; 1	Sunlight or white light	9:30–10:30 am or 3:30–4:30 pm	-	Usual care	Actigraphy	Phase delay in control group.* No other differences between the morning and afternoon groups, or control group.
Fetveit et al., 200348	Pre-post trial	11; 86; N; Y; Y; Y	6,000–8,000; 2	White	Between 8am and 11am	-	-	Actigraphy, Sleep-wake questionnaire	Improved sleep efficiency and sleep-wake score, reduced total wake time, sleep onset latency, and mesor in treatment group.* No other differences between groups.
Figueiro et al., 200232	Controlled, crossover trial	4; -; -; -; Y; Y	30; 2	Blue	6pm–8pm	-	30 lux red light	Actigraphy, body temperature, nurse observation	Phase delay and improved sleep-wakefulness in treatment period.
Kobayashi et al., 200149	Pre-post trial	10; 81; -; Y; Y; N	8,000; 1	White	11:30am –12:30pm	-	-	Nurse ratings of sleep and behavior	Improved clinical ratings of sleep-wakefulness in 80% of subjects.*
Koyama et al., 199950	Baseline-intervention trial	6; 86; N; Y; Y; Y	4,000; unstated	White	Late morning	-	-	Nurse ratings of sleep and behavior	Phase advance, increased nighttime sleep, and decreased daytime sleep in 50% of subjects.
Loving et al., 200551	Randomized, controlled, parallel-groups trial	41;68; Y; -; N; Y	8,500; 1	White	Morning, mid-day, or evening	Partial sleep deprivation	10 lux red light	Urinary melatonin, actigraphy, sleep log	Phase advance in morning light treatment group and in females in all treatment groups.*b No other differences between groups.
Loving et al., 200552	Randomized, controlled, parallel-groups trial	17; 68; Y; Y; N; Y	1,200; 1	Green	Within 1 h of waking	Partial sleep deprivation	10 lux red light	Actigraphy, sleep log	No differences between groups.
Lyketsos et al., 199953	Randomized, controlled, crossover trial	15; 81; N; N; Y; Y	10,000; 1	‘Full spectrum’	Morning	-	Dim, low-frequency, blinking light	Sleep log	Greater increase in sleep time in treatment period.
Martiny et al., 200415	Randomized, controlled, single-blind, parallel groups trial	48; 46; Y; -; N; N	10,000; 1	White	Upon awakening, but by 10am	sertraline	50 lux dim red light + sertraline	Sleep log	Greater increase in sleep duration in control group.* Later wake-up time in treatment group.*
Mishima et al., 199854	Randomized, controlled, crossover trial	22; 78; -; Y; Y; Y	5,000–8,000; 2	White	9am–11am	-	300 lux dim light	Actigraphy	Decrease in nighttime activity in treatment period.*
Mishima et al., 199455	Pre-post trial	14; 75; -; Y; Y; Y	3,000–5,000; 2	‘Full spectrum’	9am–11am	-	Usual care	Nurse observation, serum melatonin	Increase in total and nocturnal sleep time, and decrease in daytime sleep time, in treatment group.* No changes in acrophase.
Ouslander et al., 200656	Controlled, parallel-groups trial	77; 84; N; N; Y; N	1,467; 2	‘Full spectrum’	Between 5pm and 8pm	Exercise, noise reduction, nighttime routine	Usual care	Actigraphy, oximetry, observation, polysomnography	Decrease in daytime sleeping in treatment group.* No other differences between groups.
Rosenthal et al., 199057	Randomized, controlled, crossover trial	20; -; N; Y; N; N	2,500; 2	‘Full spectrum’	Between 6am and 9am	Dark goggles in evening	300 lux light and clear goggles in evening	Body temperature, questionnaire	Phase advance and improved morning alertness and earlier sleep time in treatment period.*
Satlin et al., 199258	Pre-post trial	10; 70; -; Y; Y; Y	1,500–2,000; 2	White	7pm – 9pm	-	-	Nurse ratings of sleep-wakefulness disturbances and agitation, Actigraphy	Clinical improvement in sleep-wakefulness*, nocturnal activity*, and intradaily variability. Phase advance.
Skjerve et al., 200459	Pre-post trial	10; 79; -; Y; Y; Y	5,000–8,000; 0.75	White	Between 8am and 10am	-	-	Actigraphy, SWD	Phase advance. No other differences between treatments.
Suhner et al., 200260	Pre-post trial	15; 72; N; Y; N; N	4,000; 2	White	8pm–11pm	-	-	Body temperature, sleep log, sleep quality	Phase delay in treatment period*. Effect of treatment diminished post-treatment.
Van Someren et al., 199761	Pre-post trial	22; 79; -; -; Y; Y	1,136; continuous	White	All day	-	-	Actigraphy	Increase in interdaily stability and decrease in sleep fragmentation.*

^aSignificant differences marked with an asterisk (*)

^bAuthors point out that this data is of low-quality, due to a low number of usable cases for analysis.

^cSWD = Short Scale for Sleep-Wake Disturbances