Limits...
Wake up time, light, and mood in a population sample age 40-64 years.

Endo T, Kripke DF, Ancoli-Israel S - Psychiatry Investig (2014)

Bottom Line: From 1990 to 1994, a home survey of sleep disorders among adults ages 40-64 was conducted in the City of San Diego California, using stratified representative sampling techniques.Questionnaires included the CESD depression scale and a scale of symptoms typical of winter depression.Complete data were available from 286 men and women, whose mean in-bed intervals averaged 7 hours and 42 minutes.

View Article: PubMed Central - PubMed

Affiliation: Sleep Clinic Chofu, Tokyo, Japan.

ABSTRACT

Objective: Concern that disturbances of sleep and light exposures at night might increase cancer risks have been expressed, but little actual exposure data has been collected. Measurements from a representative population sample were examined to understand the magnitude of in-bed light exposure at night and possible correlates.

Methods: From 1990 to 1994, a home survey of sleep disorders among adults ages 40-64 was conducted in the City of San Diego California, using stratified representative sampling techniques. Along with questionnaires, sleep logs, and 3-night wrist activity and pulse oximetry measures, bedside illumination was measured with a computer recording system. Questionnaires included the CESD depression scale and a scale of symptoms typical of winter depression.

Results: Complete data were available from 286 men and women, whose mean in-bed intervals averaged 7 hours and 42 minutes. The mean room illumination during the first part of the night was mean 12.7 lux (median 3.2 lux) and during the last 2 hours in bed averaged 28.7 lux (median 18.9 lux). Nocturnal light exposure was positively correlated with age, male gender, summer season, time in bed, wake-up time, and depressive symptoms.

Conclusion: Complex bi-directional interactions may take place between sleep disturbances, depression, time in bed, wake-up-time, and in-bed illumination. The most crucial light exposures appear to occur in the last 2 hours in bed, largely after dawn, so daylight exposure may be an important factor.

No MeSH data available.


Related in: MedlinePlus

CES-D depression score (ordinate) is shown versus the in-bed illumination during the early and late intervals, showing the positive correlations. CES-D: Center for Epidemiologic Studies Depression Scale, LIBP: late in-bed period, EIBP: early in-bed period.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
getmorefigures.php?uid=PMC4390587&req=5

Figure 3: CES-D depression score (ordinate) is shown versus the in-bed illumination during the early and late intervals, showing the positive correlations. CES-D: Center for Epidemiologic Studies Depression Scale, LIBP: late in-bed period, EIBP: early in-bed period.

Mentions: The mean score on the CES-D was 7.5 (median 5.0, SD 8.0; range 0-43) and that on the SAD scale was 2.4 (median 1.0, SD 2.9; range 0-20). CES-D and SAD scores were positively correlated with each other (Spearman's correlation rS=0.45, p<0.0001). The CES-D score was affected by ethnicity (ANOVA: F=3.73, DF=4, p<0.01) but not by gender, age, or day length. The CES-D scores of Hispanics and African Americans were significantly higher than non-Hispanic Whites (p<0.05). The CES-D score was positively correlated with time getting out of bed (r=0.18, p<0.01), and with the in-bed interval duration (r=0.25, p<0.0001). The CESD score was also positively correlated with log-transformed illumination during EIBP (r=0.21, p=0.001) (Figure 3) and LIBP (r=0.16, p<0.05) (Figure 3), and with the log-transformed sum of illumination during in-bed period (mean illuminationĂ—in-bed period, r=0.18, p<0.01). The positive correlation to the LIBP and the sum of illumination lost significance when the time getting out of bed or the in-bed interval length was used as a covariate. The SAD score was also positively correlated with time getting out of bed (r=0.18, p<0.01), and with the in-bed interval (Pearson's correlation: r=0.14, p<0.05), but the SAD scores were not significantly correlated with early or late in-bed illumination.


Wake up time, light, and mood in a population sample age 40-64 years.

Endo T, Kripke DF, Ancoli-Israel S - Psychiatry Investig (2014)

CES-D depression score (ordinate) is shown versus the in-bed illumination during the early and late intervals, showing the positive correlations. CES-D: Center for Epidemiologic Studies Depression Scale, LIBP: late in-bed period, EIBP: early in-bed period.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4390587&req=5

Figure 3: CES-D depression score (ordinate) is shown versus the in-bed illumination during the early and late intervals, showing the positive correlations. CES-D: Center for Epidemiologic Studies Depression Scale, LIBP: late in-bed period, EIBP: early in-bed period.
Mentions: The mean score on the CES-D was 7.5 (median 5.0, SD 8.0; range 0-43) and that on the SAD scale was 2.4 (median 1.0, SD 2.9; range 0-20). CES-D and SAD scores were positively correlated with each other (Spearman's correlation rS=0.45, p<0.0001). The CES-D score was affected by ethnicity (ANOVA: F=3.73, DF=4, p<0.01) but not by gender, age, or day length. The CES-D scores of Hispanics and African Americans were significantly higher than non-Hispanic Whites (p<0.05). The CES-D score was positively correlated with time getting out of bed (r=0.18, p<0.01), and with the in-bed interval duration (r=0.25, p<0.0001). The CESD score was also positively correlated with log-transformed illumination during EIBP (r=0.21, p=0.001) (Figure 3) and LIBP (r=0.16, p<0.05) (Figure 3), and with the log-transformed sum of illumination during in-bed period (mean illuminationĂ—in-bed period, r=0.18, p<0.01). The positive correlation to the LIBP and the sum of illumination lost significance when the time getting out of bed or the in-bed interval length was used as a covariate. The SAD score was also positively correlated with time getting out of bed (r=0.18, p<0.01), and with the in-bed interval (Pearson's correlation: r=0.14, p<0.05), but the SAD scores were not significantly correlated with early or late in-bed illumination.

Bottom Line: From 1990 to 1994, a home survey of sleep disorders among adults ages 40-64 was conducted in the City of San Diego California, using stratified representative sampling techniques.Questionnaires included the CESD depression scale and a scale of symptoms typical of winter depression.Complete data were available from 286 men and women, whose mean in-bed intervals averaged 7 hours and 42 minutes.

View Article: PubMed Central - PubMed

Affiliation: Sleep Clinic Chofu, Tokyo, Japan.

ABSTRACT

Objective: Concern that disturbances of sleep and light exposures at night might increase cancer risks have been expressed, but little actual exposure data has been collected. Measurements from a representative population sample were examined to understand the magnitude of in-bed light exposure at night and possible correlates.

Methods: From 1990 to 1994, a home survey of sleep disorders among adults ages 40-64 was conducted in the City of San Diego California, using stratified representative sampling techniques. Along with questionnaires, sleep logs, and 3-night wrist activity and pulse oximetry measures, bedside illumination was measured with a computer recording system. Questionnaires included the CESD depression scale and a scale of symptoms typical of winter depression.

Results: Complete data were available from 286 men and women, whose mean in-bed intervals averaged 7 hours and 42 minutes. The mean room illumination during the first part of the night was mean 12.7 lux (median 3.2 lux) and during the last 2 hours in bed averaged 28.7 lux (median 18.9 lux). Nocturnal light exposure was positively correlated with age, male gender, summer season, time in bed, wake-up time, and depressive symptoms.

Conclusion: Complex bi-directional interactions may take place between sleep disturbances, depression, time in bed, wake-up-time, and in-bed illumination. The most crucial light exposures appear to occur in the last 2 hours in bed, largely after dawn, so daylight exposure may be an important factor.

No MeSH data available.


Related in: MedlinePlus