Study population demographic and clinical characteristics at baseline.
| Characteristic | Total, n = 305 |
|---|---|
| Mean (SD) age, yrs | 57.00 (12.38) |
| Male, n (%) | 87 (28.5) |
| Mean (SD) BMI, kg/m2 | 25.09 (4.1)* |
| Comorbidities, n (%) | 46 (15.1) |
| Employment status†, n (%) | |
| Active | 90 (29.8) |
| Incapacitated | 84 (27.8) |
| Retired | 64 (21.2) |
| Other | 64 (21.2) |
| Mean (SD) RA disease duration, yrs | 11.77 (9.94)‡ |
| Mean (SD) DAS28-CRP | 3.54 (1.5)§ |
| DAS28-CRP categorization, n (%) | |
| Remission/LDA | 138 (44.4)§ |
| Moderate to high | 173 (55.6)§ |
| Current RA treatment, n (%) | |
| Conventional DMARD only | 171 (56.4)# |
| Biologic DMARD¶ | 132 (43.6)# |
| Glucocorticoids | 138 (45.8)†† |
| Sleep medication, n (%) | |
| Never | 217 (71.1) |
| Currently | 58 (19.0) |
| Concurrent medication, n (%) | |
| Antidepressants | 37 (12.1) |
| Antidepressant type: sedative | 13 (35.1)‡‡ |
| Antiallergy medication | 11 (3.6) |
| Analgesia | 149 (48.9) |
| Antihypertensives | 74 (24.3) |
| Concurrent consumption, n (%) | |
| Caffeinated drinks | 245 (84.2)§§ |
| Alcohol | 148 (50.2)‡ |
↵* n = 293.
↵† Incapacitated included sick leave, early retirement, permanently invalid, n = 302. Other includes unemployed, at home, not known.
↵‡ n = 295.
↵§ n = 311.
↵¶ Biologic DMARD includes abatacept, adalimumab, etanercept, infliximab, and rituximab.
↵# n = 303.
↵†† n = 301.
↵‡‡ n = 37 (current antidepressant users only).
↵§§ n = 291. BMI: body mass index; DAS28-CRP: 28-joint Disease Activity Score (C-reactive protein); DMARD: disease-modifying antirheumatic drug; LDA: low disease activity; RA: rheumatoid arthritis.