Table 1. Clinical characteristics of study participants.
| All | Men | Women | ||
|---|---|---|---|---|
| (n = 9,611) | (n = 3,157) | (n = 6,454) | p* | |
| Age, y | 53 ± 14 | 55 ± 14 | 52 ± 13 | <0.01 |
| Body mass index, kg/m2 | 22.3 ± 3.3 | 23.4 ± 3.1 | 21.7 ± 3.2 | <0.01 |
| Current smoker, % | 14.7 | 31.2 | 6.6 | <0.01 |
| Frequent alcohol drinker, % | 22.9 | 49.8 | 9.7 | <0.01 |
| Irregular sleep schedule, % | 10.6 | 13.7 | 9.2 | <0.01 |
| Sleep medication, % | 5.3 | 4.9 | 5.6 | 0.19 |
| Analgesic drug, % | 3.3 | 1.7 | 4.1 | <0.01 |
| GERD, % | 22.9 | 22.5 | 23.1 | 0.52 |
| No. unfavorable dietary behaviors | 0.8 ± 0.9 | 1.0 ± 0.9 | 0.7 ± 0.8 | <0.01 |
| Knee pain, % | 29.0 | 25.9 | 30.6 | <0.01 |
| Group categorized by the tertile of NRS score, % | ||||
| T1-NRS (NRS score ≥0 and <10) | 12.4 | 10.8 | 13.1 | |
| T2-NRS (NRS score ≥10 and <30) | 9.6 | 8.5 | 10.2 | |
| T3-NRS (NRS score ≥30) | 7.1 | 6.6 | 7.3 | |
| Low back pain, % | 42.0 | 46.0 | 40.1 | <0.01 |
| Group categorized by the tertile of RDQ score, % | ||||
| T1-RDQ (RDQ score = 0) | 12.1 | 13.7 | 11.4 | |
| T2-RDQ (RDQ score = 1 or 2) | 14.3 | 16.2 | 13.4 | |
| T3-RDQ(RDQ score ≥3) | 15.6 | 16.1 | 15.3 | |
| Short sleep duration, % | 29.4 | 25.9 | 31.1 | <0.01 |
| Poor sleep quality, % | 17.6 | 17.2 | 17.8 | 0.46 |
Values are expressed as mean ± standard deviation or percentage.
GERD: gastroesophageal reflux disease, NRS: numerical response scale, RDQ: Roland-Morris Disability Questionnaire.
* p value in comparison with men and women.
Participants with knee pain were subdivided into 3 groups according to tertiles of the NRS score. Groups in the first, second and third tertile of NRS were designed as T1-NRS, T2-NRS and T3-NRS, respectively.
Participants with low back pain were subdivided into 3 groups according to tertiles of the RDQ score. Groups in the first, second and third tertile of RDQ were designed as T1-RDQ, T2-RDQ and T3-RDQ, respectively.