Table 3.
The associations between current smoking status and HRQOL, disease activity, symptom change, and global disability by MS subtype.
| Variable (mean and S.D. or percentage) |
RR Adjustedδ β/OR (95% CI) (N=512) |
P | SP/PP/PR Adjusted β/OR (95% CI) (N=307) |
P | SP Adjusted β/OR (95% CI) (N=199) |
P | PP/PR Adjusted β/OR (95% CI) (N=108) |
P |
|---|---|---|---|---|---|---|---|---|
| HRQOL | ||||||||
| PCS¥ | −3.43 (−6.24, −0.62) | 0.017 | −3.54 (−6.39, −0.69) | 0.015 | −2.57 (−6.36, 1.21) | 0.18 | −4.51 (−9.09, 0.07) | 0.054 |
| PCS binary (1=Below/Far Below average; 0=At/Above average) |
2.40 (1.28, 4.49) | 6.4x10−3 | 2.65 (0.32, 21.99) | 0.37 | 2.30 (0.25, 21.20) | 0.46 | − | − |
| MCS¥ | −4.33 (−7.10, −1.56) | 2.2x10−3 | −2.82 (−7.01, 1.37) | 0.19 | −2.81 (−8.19, 2.57) | 0.30 | −0.93 (−8.03, 6.17) | 0.80 |
| MCS binary (1=Below/Far Below average; 0=At/Above average) |
2.40 (1.34, 4.28) | 3.1x10−3 | 1.19 (0.53, 2.64) | 0.68 | 1.12 (0.38, 3.26) | 0.84 | 0.88 (0.25, 3.13) | 0.84 |
| Disease activity | ||||||||
| Relapse in the previous 6 months (1=Yes; 0=No/Don’t Know) |
2.26 (1.21, 4.23) | 0.011 | 1.32 (0.49, 3.55) | 0.59 | 1.69 (0.48, 5.94) | 0.42 | 1.05 (0.18, 5.96) | 0.96 |
| Progressive worsening of symptoms in previous 6 months (1=Yes; 0=No) |
1.57 (0.81, 3.04) | 0.18 | 1.06 (0.48, 2.33) | 0.89 | 1.00 (0.35, 2.86) | 1.00 | 1.39 (0.38, 5.04) | 0.62 |
| Compare MS symptoms to 6 months ago? (1=Much better; 7=Much Worse) |
2.19 (1.23, 3.89) | 7.4x10−3 | 1.40 (065, 2.95)γ | 0.39 | 1.09 (0.41, 2.90)γ | 0.87 | 1.99 (0.59, 6.73) | 0.27 |
| Performance Scales (0=normal) | ||||||||
| Mobility (0 to 5) | 1.51 (0.92, 2.47) | 0.10 | 1.07 (0.53, 2.16)γ | 0.86 | 0.96 (0.39, 2.39)γ | 0.93 | 1.09 (0.34, 3.47)γ | 0.88 |
| Dexterity (0 to 4) | 2.79 (1.69, 4.59) | 5.8x10−5 | 1.55 (0.75, 3.21) | 0.24 | 1.00 (0.41, 2.49) | 0.99 | 2.90 (0.83, 10.15) | 0.095 |
| Vision (0 to 4) | 1.85 (1.12, 3.07) | 0.017 | 2.70 (1.33, 5.48)α | 5.9x10−3 | 2.21 (0.88, 5.52)α | 0.09 | 3.20 (1.00, 10.22) | 0.049 |
| Fatigue (0 to 5) | 2.30 (1.39, 3.81) | 1.3x10−3 | 3.01 (1.52, 5.98)γ | 1.6x10−3 | 2.03 (0.87, 4.77) | 0.10 | 4.74 (1.47, 15.32)γ | 9.2x10−3 |
| Cognitive Symptoms (0 to 4) | 1.89 (1.12, 3.21)γ | 0.017 | 1.91 (0.92, 3.97) | 0.08 | 1.63 (0.64, 4.17)γ | 0.31 | 2.03 (0.61, 6.81) | 0.25 |
| Bladder/Bowel (0 to 4) | 1.67 (0.99, 2.85) | 0.057 | 1.09 (0.52, 2.28) | 0.82 | 0.81 (0.29, 2.24) | 0.68 | 1.44 (0.44, 4.64) | 0.55 |
| Sensory Symptoms (0 to 5) | 1.42 (0.85, 2.36)γ | 0.18 | 1.48 (0.73, 2.99) | 0.27 | 1.45 (0.56, 3.73) | 0.44 | 1.42 (0.47, 4.35)γ | 0.54 |
| Spasticity Symptoms (0 to 4) | 1.99 (1.19, 3.32) | 8.3x10−3 | 1.07 (0.52, 2.20) | 0.85 | 0.79 (0.31, 2.01) | 0.63 | 1.54 (0.49, 4.82) | 0.46 |
| Functional Scales (0=normal) | ||||||||
| Depression (0 to 4) | 1.81 (1.06, 3.08) | 0.027 | 1.96 (0.97, 3.94) | 0.059 | 2.76 (1.11, 6.87) | 0.03 | 1.21 (0.40, 3.69) | 0.74 |
| Tremor and Coordination (0 to 4) | 2.39 (1.43, 4.01)γ | 9.0x10−4 | 3.04 (1.48, 6.22) | 2.4x10−3 | 3.47 (1.39, 8.071) | 7.9x10−3 | 2.16 (0.67, 7.01) | 0.20 |
| Pain (0 to 4) | 2.09 (1.24, 3.52) | 5.9x10−3 | 3.04 (1.51, 6.12) | 1.8x10−3 | 2.15 (0.84, 5.47) | 0.11 | 4.94 (1.62, 14.99)γ | 4.8x10−3 |
| Global Disability | ||||||||
| IRT disability¥ | 6.99 (3.01, 10.98) | 6.2x10−4 | 6.99 (1.89, 12.09) | 7.4x10−3 | 6.02 (−0.40, 12.44) | 0.07 | 7.45 (−1.42, 16.33) | 0.10 |
| PDDS (0=normal; 8=Bedridden) | 1.55 (0.96, 2.50) | 0.075 | 1.12 (0.57, 2.22)γ | 0.74 | 1.03 (0.43, 2.44)γ | 0.95 | 1.00 (0.32, 3.15)γ | 1.00 |
BMI: body mass index; IRT disability: Item Response Theory summed score of global MS disability; MCS: mental component summary; OR: odds ratio; PCS: physical component summary; PDDS: patient derived disease steps. PP: primary progressive; PR: progressive relapsing; RR: relapsing remitting; SP: secondary progressive.
The measures of association reported for these outcomes are betas from linear regression models. The remaining measures of association are odds ratios.
Models were adjusted for gender, BMI, age of symptom onset, duration from diagnosis, and age at interview.
Smoking status violated the parallel lines assumption, but constrained to the assumption.
The partial proportional odds model did not converge, however smoking status met the parallel lines assumption in the unadjusted model, therefore all other predictors were constrained to the assumption.