Table 3.
Multivariable Longitudinal Analyses Using Mixed Repeated Measures Models to Evaluate the Associations Between Mastectomy Status and Pain Outcomes
| Variable | Pain Severity | Pain Interference | ||||
|---|---|---|---|---|---|---|
| Estimated Coefficient | Standard Error | P | Estimated Coefficient | Standard Error | P | |
| Mastectomy Yes vs. No | 0.36 | 0.23 | .122 | 0.07 | 0.29 | .804 |
| Time Point x Mastectomy | .069 | .030 | ||||
| Pain Outcome Baseline | 0.50 | 0.05 | <.001 | 0.54 | 0.06 | <.001 |
| Assessment of Time Effect | ||||||
| T2 (vs. T1) | 0.04 | 0.13 | .741 | −0.04 | 0.15 | .776 |
| T3 (vs. T1) | −0.26 | 0.13 | .038 | −0.53 | 0.14 | <.001 |
| T4 (vs. T1) | −0.37 | 0.14 | .007 | −0.70 | 0.15 | <.001 |
| Age at diagnosis (years) | 0.01 | 0.01 | .204 | −0.006 | 0.01 | .531 |
| Race/Ethnicity | ||||||
| Black, non-Hispanic (vs. White, non-Hispanic) | 0.97 | 0.33 | .003 | 0.63 | 0.34 | .067 |
| Hispanic (vs. White, non-Hispanic) | 0.13 | 0.25 | .605 | 0.03 | 0.30 | .914 |
| Other/missing (vs. White, non-Hispanic) | −0.21 | 0.29 | .469 | −0.18 | 0.35 | .604 |
| Chemotherapy Yes vs. No | 0.48 | 0.19 | .012 | 0.40 | 0.21 | .058 |
| Reconstruction Yes vs. No | 0.20 | 0.26 | .430 | 0.29 | 0.32 | .363 |
NOTE. T1=1 month post-surgery; T2=6 months post-surgery; T3=12 months post-surgery; T4=18 months post-surgery.
Body mass index, adjuvant radiation therapy, and adjuvant hormone therapy were not significantly associated with pain severity or interference in the longitudinal univariate analysis and were not included in the multivariable analysis.