Improvement in Fatigue, Sleepiness, and Health-Related Quality of Life with Bright Light Treatment in Persons with Seasonal Affective Disorder and Subsyndromal SAD
Table 1
Mean values (SD) for daytime sleepiness, fatigue, and quality of life in subjects with mild-to-moderate winter depressive mood at baseline, posttreatment, and at the one-month followup (). Treatment refers to bright light therapy in a light room.
Measure
Baseline
Posttreatment
Followup
Within-subjects repeated measures ANOVA
Mean
(SD)
Mean
(SD)
Mean
(SD)
(df)5
P value
Fatigue questionnaire (FQ)1
19.3
(4.2)
10.7
(7.7)
9.5
(9.8)
24.7(1.7,79.4)
<.001
Epworth Sleepiness Scale (ESS)2
10.0
(4.1)
6.4
(4.0)
5.5
(3.1)
59.1 (2,90)
<.001
VAS3
Mood
49.5
(11.7)
65.5
(15.6)
70.4
(15.1)
57.1 (1.6,75.8)
<.001
Sleepiness
36.1
(14.9)
60.8
(20.0)
68.5
(14.2)
82.8 (1.7,77.9)
<.001
SF-364
Physical health (PCS)
47.7
(7.4)
49.0
(6.7)
51.1
(6.6)
6.0 (2,92)
=.004
Physical functioning (PF)
83.3
(12.9)
87.3
(11.5)
90.2
(10.9)
11.7 (1.8,80.6)
<.001
Role—physical (RP)
58.5
(33.1)
78.2
(31.1)
90.4
(19.2)
20.0 (2,92)
<.001
Bodily pain (BP)
57.6
(26.8)
71.7
(23.6)
76.6
(23.6)
17.6 (1.8,80.5)
<.001
General health (GH)
63.8
(23.1)
70.9
(19.0)
75.4
(17.0)
14.6 (2,92)
<.001
Mental health (MCS)
31.8
(10.4)
46.2
(11.0)
49.8
(8.9)
66.7 (2,92)
<.001
Vitality (VT)
30.1
(16.8)
61.9
(22.6)
69.1
(17.1)
82.5 (2,92)
<.001
Social functioning (SF)
62.8
(23.4)
80.9
(21.8)
91.5
(14.1)
35.8 (2,92)
<.001
Role—emotional (RE)
43.3
(41.1)
80.1
(29.2)
88.7
(24.4)
43.5 (1.6,72.3)
<.001
Mental health (MH)
56.4
(16.6)
75.1
(18.4)
79.6
(14.5)
38.4 (2,92)
<.001
N
(%)
N
(%)
N
(%)
Proportion with ESS total score ≤86
13
(27.7)
38
(80.0)
39
(84.8)
Proportion with FQ total score ≤127
3
(6.4)
34
(72.3)
39
(83.0)
1High values correspond to high level of fatigue (feeling worse). 2High values correspond to high level of sleepiness (feeling worse). 3Four uni- or Two bivariate 0–100 visual analogue scales. Low values correspond to high level of depressive mood/sleepiness (feeling worse). 4Low values correspond to lower level of functioning (feeling worse). 5When Mauchly’s test of sphericity was significant, a Greenhouse-Geisser correction of degrees of freedom was used. values refer to differences between baseline and the one-month followup. 6Scores <8 are considered to be within the normal range [26]. 7The score 12 represents approximately the population mean [25].