Background
Methods
Institutional review board (IRB) approval
Patients and setting
Measures
Statistical analysis
Results
Patient enrollment
Patient differences across sites
Demographic variable | Combined | N. CA | Detroit | Boston |
---|---|---|---|---|
N = 5239* | N = 3164 | N = 967 | N = 1108 | |
Age, mean (SD) years
| 73.8 ± 6.9 | 73.7 ± 6.8 | 73.8 ± 6.9 | 73.8 ± 7.1 |
Sex, N (%)
| ||||
Male
| 1852 (35%) | 1154 (36%) | 289 (30%) | 409 (37%) |
Female
| 3387 (65%) | 2010 (64%) | 678 (70%) | 699 (63%) |
Hispanic, N (%)
| 305 (6%) | 270 (9%) | 21 (2%) | 14 (1%) |
Race, N (%)
| ||||
Black or African American
| 797 (15%) | 226 (7%) | 485 (50%) | 86 (8%) |
Native American Indian/Alaskan/Hawaiian or other Pacific Islander
| 44 (1%) | 40 (1%) | 4 (0%) | 0 (0%) |
Asian
| 198 (4%) | 171 (5%) | 18 (2%) | 9 (1%) |
Caucasian
| 3843 (73%) | 2430 (77%) | 432 (45%) | 981 (89%) |
Other
| 299 (6%) | 246 (8%) | 26 (3%) | 27 (2%) |
Education, N (%)
| ||||
Less than high school graduate
| 314 (6%) | 144 (5%) | 154 (16%) | 16 (1%) |
High school graduate or obtained a GED/Vocational, technical/trade school
| 1450 (28%) | 794 (25%) | 382 (40%) | 274 (25%) |
Some college
| 1275 (24%) | 978 (31%) | 234 (24%) | 63 (6%) |
Four year college graduate
| 1290 (25%) | 605 (19%) | 89 (9%) | 596 (54%) |
Professional or graduate degree
| 894 (17%) | 633 (20%) | 105 (11%) | 156 (14%) |
Marital, N (%)
| ||||
Married/living with a partner
| 3191 (61%) | 1850 (58%) | 451 (47%) | 890 (80%) |
Separated/divorced
| 602 (11%) | 423 (13%) | 147 (15%) | 32 (3%) |
Never married and presently single
| 256 (5%) | 163 (5%) | 69 (7%) | 24 (2%) |
Widowed
| 1175 (22%) | 716 (23%) | 299 (31%) | 160 (14%) |
Employment, N (%)
| ||||
Working full-time/part-time
| 602 (11%) | 367 (12%) | 166 (15%) | 69 (7%) |
Retired (not due to ill health)
| 4250 (81%) | 2535 (80%) | 913 (82%) | 802 (83%) |
Retired or disabled because of ill health
| 146 (3%) | 71 (2%) | 12 (1%) | 63 (7%) |
Other
| 220 (4%) | 177 (6%) | 11 (1%) | 32 (3%) |
Legal representation for back pain, N (%)
| ||||
Yes
| 31 (1%) | 23 (1%) | 8 (1%) | 0 (0%) |
No
| 5196 (99%) | 3136 (99%) | 956 (99%) | 1104 (100%) |
Smoking status, N (%)
| ||||
Never Smoked
| 2901 (55%) | 1570 (50%) | 675 (70%) | 656 (59%) |
Quit smoking over a year ago
| 1999 (38%) | 1422 (45%) | 169 (17%) | 408 (37%) |
Current smoker/quit less than a year ago
| 324 (6%) | 164 (5%) | 121 (13%) | 39 (4%) |
Days between index visit and baseline assessment, mean (SD)
| 14.6 ± 5.3 | 16.0 ± 4.6 | 16.3 ± 5.3 | 8.9 ± 2.7 |
Baseline symptoms and outcomes | Combined | N. CA | Detroit | Boston |
---|---|---|---|---|
N = 5239* | N = 3164 | N = 967 | N = 1108 | |
RMDQ (0–24), mean (SD)
| 9.5 ± 6.4 | 9.7 ± 6.0 | 12.8 ± 5.9 | 6.4 ± 6.4 |
Back pain duration, N (%)
| ||||
< 1 month
| 1749 (33%) | 1215 (38%) | 230 (24%) | 304 (27%) |
1 - 3 months
| 1015 (19%) | 715 (23%) | 137 (14%) | 163 (15%) |
3 - 6 months
| 344 (7%) | 243 (8%) | 46 (5%) | 55 (5%) |
6 - 12 months
| 313 (6%) | 165 (5%) | 96 (10%) | 52 (5%) |
1 - 5 years
| 776 (15%) | 399 (13%) | 197 (20%) | 180 (16%) |
> 5 years
| 1037 (20%) | 426 (13%) | 261 (27%) | 350 (32%) |
Back pain intensity (0–10), mean (SD)
| 5.0 ± 2.8 | 4.9 ± 2.7 | 6.2 ± 2.8 | 4.5 ± 2.7 |
Leg pain intensity (0–10), mean (SD)
| 3.4 ± 3.3 | 3.5 ± 3.2 | 4.2 ± 3.6 | 2.6 ± 3.1 |
BPI Interference (0–10), mean (SD)
| 3.3 ± 2.5 | 3.4 ± 2.5 | 3.8 ± 2.6 | 2.5 ± 2.3 |
PHQ-4 (0–12), mean (SD)
| 1.6 ± 2.5 | 1.9 ± 2.5 | 1.8 ± 2.8 | 0.4 ± 1.6 |
EQ-5D index (-0.1-1), mean (SD)
| 0.76 ± 0.17 | 0.76 ± 0.17 | 0.69 ± 0.20 | 0.81 ± 0.16 |
EQ5D VAS (0–100), mean (SD)
| 74.3 ± 18.4 | 73.6 ± 18.9 | 74.0 ± 18.4 | 76.6 ± 16.9 |
Falls in past 3 weeks, N (%)
| ||||
Patients with one or more fall
| 385 (7%) | 288 (9%) | 81 (8%) | 16 (1%) |
How many of these falls caused one or more injury**?
| 179 (46%) | 121 (42%) | 51 (63%) | 7 (44%) |
Back Pain Recovery Expectations (0–10), mean (SD)
| 5.5 ± 3.7 | 5.7 ± 3.6 | 4.9 ± 3.7 | 5.1 ± 4.0 |
Relationship of patient sociodemographic characteristics to patient-reported pain, physical disability, and HRQoL
Association of diagnosis with pain, function, and HRQoL
Diagnosis codes | N (%) | RMDQ | Back pain intensity | Leg pain intensity |
---|---|---|---|---|
Non-Specific: lumbago, backache, sprains and strains
| 3560 (67.95%) | 4.0 9.0 15.0 (9.5 ± 6.5)* | 3.0 5.0 7.0 (5.1 ± 2.8) | 0.0 2.0 6.0 (3.0 ± 3.3) |
Back and Leg: back pain with radiation, sciatica
| 1091 (20.82%) | 5.0 10.0 15.0 (10.0 ± 6.2) | 3.0 5.0 7.0 (4.9 ± 2.9) | 3.0 5.0 7.0 (5.1 ± 3.0) |
Spinal Stenosis
| 288 (5.50%) | 5.0 10.0 15.2 (10.0 ± 6.4) | 3.0 5.0 6.0 (4.6 ± 2.6) | 0.0 5.0 6.0 (4.0 ± 3.2) |
Others
| 300 (5.73%) | 2.0 7.0 13.0 (8.0 ± 6.6) | 3.0 5.0 7.0 (4.7 ± 2.7) | 0.0 0.0 4.0 (2.2 ± 2.9) |
Multivariable analysis of association of baseline characteristics with RMDQ and pain
Independent variable | Levels | Dependent variable: RMDQ (0–24) | Dependent variable: back pain intensity (0–10) | ||
---|---|---|---|---|---|
Coef* (95% CI) | P-value | Coef* (95% CI) | P-value | ||
Site
|
Boston
| Ref | <0.001 | Ref | <0.001 |
Detroit
| 5.22 (4.56, 5.88) | 1.26 (0.96, 1.56) | |||
N. CA
| 3.30 (2.77, 3.82) | 0.59 (0.35, 0.83) | |||
Age
|
(Per year)
| 0.03 (0.00, 0.05) | 0.048 | 0.00 (-0.01, 0.01) | 0.983 |
Sex
|
Male
| Ref | <0.001 | Ref | <0.001 |
Female
| 1.10 (0.73, 1.46) | 0.50 (0.34, 0.67) | |||
Hispanic
|
Yes
| Ref | 0.578 | Ref | 0.087 |
No
| -0.24 (-1.10, 0.62) | -0.34 (-0.73, 0.05) | |||
Race
|
Black or African American
| Ref | 0.011 | Ref | <0.001 |
Native American Indian/Alaskan/Hawaiian or other Pacific Islander
| -0.13 (-1.93, 1.67) | -0.05 (-0.88, 0.77) | |||
Asian
| -0.29 (-1.25, 0.68) | -0.50 (-0.94, -0.06) | |||
Caucasian
| -0.76 (-1.27, -0.25) | -0.72 (-0.96, -0.49) | |||
Other
| 0.16 (-0.79, 1.10) | -0.51 (-0.94, -0.07) | |||
Education
|
Less than high school graduate
| Ref | <0.001 | Ref | <0.001 |
High school graduate/obtained a GED/Vocational, technical, or trade school
| -1.13 (-1.87, -0.39) | -0.35 (-0.69, -0.02) | |||
Some college
| -2.20 (-2.96, -1.44) | -0.40 (-0.75, -0.06) | |||
Four year college graduate
| -2.99 (-3.78, -2.20) | -0.80 (-1.16, -0.44) | |||
Professional or graduate degree
| -3.04 (-3.85, -2.23) | -1.05 (-1.42, -0.68) | |||
Marital
|
Married/living with a partner
| Ref | 0.386 | Ref | 0.086 |
Separated/divorced
| 0.20 (-0.34, 0.73) | 0.07 (-0.17, 0.32) | |||
Never married and presently single
| 0.45 (-0.31, 1.21) | 0.25 (-0.10, 0.60) | |||
Widowed
| 0.33 (-0.12, 0.78) | 0.25 (0.04, 0.45) | |||
Employment
|
Working full-time/part-time
| Ref | <0.001 | Ref | 0.003 |
Retired (not due to ill health)
| 0.86 (0.33, 1.38) | 0.30 (0.06, 0.54) | |||
Retired or disabled because of ill health
| 3.90 (2.82, 4.99) | 0.87 (0.38, 1.37) | |||
Other
| 0.60 (-0.33, 1.54) | 0.08 (-0.34, 0.51) | |||
Legal rep.
|
Yes
| Ref | 0.059 | Ref | 0.115 |
No
| -2.00 (-4.07, 0.08) | -0.76 (-1.71, 0.19) | |||
Smoking status
|
Never Smoked
| Ref | <0.001 | Ref | 0.012 |
Quit smoking over a year ago
| 0.39 (0.04, 0.74) | 0.13 (-0.03, 0.29) | |||
Current smoker/quit less than a year ago
| 1.46 (0.77, 2.15) | 0.45 (0.14, 0.77) | |||
ICD9 code
|
Non-specific
| Ref | <0.001 | Ref | 0.051 |
Back and Leg
| 1.00 (0.59, 1.42) | -0.04 (-0.23, 0.15) | |||
Spinal Stenosis
| 1.08 (0.35, 1.81) | -0.46 (-0.79, -0.13) | |||
Others
| -0.75 (-1.46, -0.05) | -0.14 (-0.47, 0.18) | |||
Pain duration
|
0 - 1 month
| Ref | <0.001 | Ref | <0.001 |
1 - 3 month
| 0.62 (0.16, 1.08) | 0.13 (-0.08, 0.34) | |||
3 - 6 month
| 0.61 (-0.07, 1.30) | 0.33 (0.02, 0.65) | |||
6 - 12 month
| 1.07 (0.35, 1.78) | 0.42 (0.10, 0.75) | |||
1 - 5 years
| 1.80 (1.29, 2.31) | 0.46 (0.23, 0.69) | |||
> 5 years
| 2.03 (1.56, 2.50) | 0.53 (0.31, 0.74) | |||
Time from index visit to assessment
(per day, 0–21)
| -0.04 (-0.08, -0.00) | 0.029 | -0.07 (-0.08, -0.05) | <0.001 |