Table 4

Comparison between poor and good sleepers (sorted by P value)

Variables

PSQI ≤7

PSQI >7

P

n = 203

n = 111

SDS

44.15 ± 9.44

52.95 ± 9.83

0.000

SAS

45.78 ± 7.07

53.07 ± 7.77

0.000

BASDAI

2.98 ± 1.87

4.66 ± 2.03

0.000

BASFI

1.23 ± 1.83

2.39 ± 2.51

0.000

Nocturnal pain (VAS)

2.89 ± 2.64

5.17 ± 2.94

0.000

Total back pain (VAS)

3.12 ± 2.49

5.18 ± 2.57

0.000

Overall assessment of health (VAS)

4.67 ± 2.79

6.59 ± 2.58

0.000

Morning stiffness (minutes)

9.53 ± 26.48

16.24 ± 29.70

0.002

Age (years)

26.83 ± 8.03

29.70 ± 8.59

0.002

ESR (mm/h)

14.51 ± 15.44

20.98 ± 23.21

0.018

CRP (mg/dl)

1.32 ± 1.65

2.16 ± 5.33

0.039

Years of education

4.46 ± 0.89

4.25 ± 0.98

0.058

BASMI

1.29 ± 1.87

1.59 ± 1.93

0.069

Disease duration (years)

5.70 ± 4.57

6.74 ± 5.40

0.116

Fingertip-to-floor distance (cm)

9.65 ± 13.51

9.99 ± 14.09

0.859

BASDAI, Bath Ankylosing Spondylitis Disease Activity Index; BASFI, Bath Ankylosing Spondylitis Functional Index; BASMI, Bath Ankylosing Spondylitis Metrology Index; CRP, C-reactive protein; ESR, erythrocyte sedimentation rate; PSQI, Pittsburgh Sleep Quality Index; SAS, Self-rating Anxiety Scale; SDS, Self-rating Depression Scale; VAS, visual analogue scale.

Li et al. Arthritis Research & Therapy 2012 14:R215   doi:10.1186/ar4054