Table 1.
Characteristics of CLBP patients according to presence of depression
| Total (N = 425) | Depression (PHQ-9 ≥ 10) (N = 70) |
No Depression (PHQ-9 < 10) (N = 355) |
P value | |
|---|---|---|---|---|
| Age, Mean ± SD | 53.90 ± 14.16 | 45.91 ± 13.73 | 55.48 ± 13.73 | <0.001 |
| Female, n (%) | 187 (44.00) | 33 (47.14) | 154 (43.38) | 0.562 |
| Employment status, n (%) | 0.589 | |||
| Not currently employed | 164 (38.59) | 25 (35.71) | 139 (39.15) | |
| Employed | 261 (61.41) | 45 (64.29) | 216 (60.85) | |
| Annual household income, n (%) | 0.079 | |||
| < ¥3million | 83 (19.53) | 22 (31.43) | 61 (17.18) | |
| ¥3million to < ¥5million | 100 (23.53) | 15 (21.43) | 85 (23.94) | |
| ¥5million to < ¥8million | 113 (26.59) | 15 (21.43) | 98 (27.61) | |
| ¥8million or more | 97 (22.82) | 12 (17.14) | 85 (23.94) | |
| Decline to answer | 32 (7.53) | 6 (8.57) | 26 (7.32) | |
| Marital status, n (%) | 0.021 | |||
| Single/Divorced/Separated/Widowed | 138 (32.47) | 31 (44.29) | 107 (30.14) | |
| Married/living with partner | 287 (67.53) | 39 (55.71) | 248 (69.86) | |
| Education level, n (%) | 0.063 | |||
| Less than university education | 218 (51.29) | 43 (61.43) | 175 (49.30) | |
| University education or higher | 207 (48.71) | 27 (38.57) | 180 (50.70) | |
| Body mass index category, n (%) | 0.137 | |||
| Underweight | 52 (12.24) | 9 (12.86) | 43 (12.11) | |
| Normal weight | 280 (65.88) | 39 (55.71) | 241 (67.89) | |
| Overweight | 70 (16.47) | 16 (22.86) | 54 (15.21) | |
| Obese | 19 (4.47 %) | 4 (5.71) | 15 (4.23) | |
| Decline to provide weight | 4 (0.94 %) | 2 (2.86) | 2 (0.56) | |
| Smoking behavior, n (%) | 0.088 | |||
| Never smoked | 182 (42.82) | 34 (48.57) | 148 (41.69) | |
| Former smoker | 132 (31.06) | 14 (20.00) | 118 (33.24) | |
| Current smoker | 111 (26.12) | 22 (31.43) | 89 (25.07) | |
| Alcohol use, n (%) | 0.975 | |||
| Do not drink | 116 (27.29) | 19 (27.14) | 97 (27.32) | |
| Drink alcohol | 309 (72.71) | 51 (72.86) | 258 (72.68) | |
| Vigorous exercise at least one day in the past month, n (%) | 0.198 | |||
| Do not exercise | 213 (50.12) | 40 (57.14) | 173 (48.73) | |
| Exercise | 212 (49.88) | 30 (42.86) | 182 (51.27) | |
| Charlson comorbidity index, Mean ± SD | 0.51 ± 2.23 | 0.83 ± 3.64 | 0.44 ± 1.83 | 0.186 |
| Sleep difficulties, n (%) | 82 (19.29) | 35 (50.00) | 47 (13.24) | <0.001 |
| Severity of LBP, n (%) | <0.001 | |||
| Mild | 186 (47.45) | 19 (29.23) | 167 (51.07) | |
| Moderate | 172 (43.88) | 34 (52.31) | 138 (42.20) | |
| Severe | 34 (8.67) | 12 (18.46) | 22 (6.73) | |
| Missing | 33 | 5 | 28 | |
| Severity of pain in the prior week (0–10), Mean ± SD | 4.48 ± 2.31 | 5.80 ± 2.26 | 4.23 ± 2.23 | <0.001 |
| Current severity of pain (0–10), Mean ± SD | 4.59 ± 2.28 | 5.86 ± 2.27 | 4.34 ± 2.20 | <0.001 |
| Frequency of problems with pain, n (%) | 0.002 | |||
| Daily | 188 (44.24) | 44 (62.86) | 144 (40.56) | |
| 4–6 times a week | 63 (14.82) | 12 (17.14) | 51 (14.37) | |
| 2–3 times a week | 82 (19.29) | 10 (14.29) | 72 (20.28) | |
| Once a week | 39 (9.18) | 3 (4.29) | 36 (10.14) | |
| 2–3 times a month | 35 (8.24) | 0 (0.00) | 35 (9.86) | |
| Once a month or less often | 18 (4.24) | 1 (1.43) | 17 (4.79) | |
| Type of diagnosing doctor for LBP, n (%) | 0.028 | |||
| General internist | 18 (4.24) | 4 (5.71) | 14 (3.94) | |
| Gynecologist | 5 (1.18) | 0 (0.00) | 5 (1.41) | |
| Orthopedist | 353 (83.06) | 54 (77.14) | 299 (84.23) | |
| Rheumatologist | 4 (0.94) | 3 (4.29) | 1 (0.28) | |
| Pain management specialist | 3 (0.71) | 1 (1.43) | 2 (0.56) | |
| Other | 42 (9.88) | 8 (11.43) | 34 (9.58) | |
| Type of prescribing doctor, n (%) | 0.150 | |||
| General internist | 28 (16.87) | 6 (15.38) | 22 (17.32) | |
| Gynecologist | 2 (1.20) | 0 (0.00) | 2 (1.57) | |
| Orthopedist | 116 (69.88) | 24 (61.54) | 92 (72.44) | |
| Rheumatologist | 5 (3.01) | 3 (7.69) | 2 (1.57) | |
| Pain management specialist | 1 (0.60) | 0 (0.00) | 1 (0.79) | |
| Other | 14 (8.43) | 6 (15.38) | 8 (6.30) | |
| Missing | 259 | 31 | 228 | |
| Duration of LBP (months), Mean ± SD | 112 ± 120 | 96 ± 99 | 115 ± 123 | 0.227 |
| Current use of a prescription medication for pain, n (%) | 0.002 | |||
| No | 259 (60.94) | 31 (44.29) | 228 (64.23) | |
| Yes | 166 (39.06) | 39 (55.71) | 127 (35.77) | |
| Current use of NSAIDs prescription for pain, n (%) | 0.049 | |||
| No | 40 (24.10) | 14 (35.90) | 26 (20.47) | |
| Yes | 126 (75.90) | 25 (64.10) | 101 (79.53) | |
| Missing | 259 | 31 | 228 | |
| Use of an OTC product for pain, n (%) | 0.861 | |||
| No | 306 (72.00) | 51 (72.86) | 255 (71.83) | |
| Yes | 119 (28.00) | 19 (27.14) | 100 (28.17) | |
| Use of an herbal product for pain, n (%) | 0.441 | |||
| No | 413 (97.18) | 69 (98.57) | 344 (96.90) | |
| Yes | 12 (2.82) | 1 (1.43) | 11 (3.10) |
aNSAIDS are prescription drugs in Japan. CLBP chronic low back pain, LBP low back pain, NSAIDs non-steroidal anti-inflammatory drugs, OTC over-the-counter, PHQ-9 Patient Health Questionaire-9