Table 3.
Factors Associated with Receipt of Radiotherapy after BCS among 5,889 Women Aged 80 and Older who Underwent BCS.*
| n | % Received Radiotherapy after BCS | Adjusted Relative Risk of Radiotherapy after BCS† | |
|---|---|---|---|
| Overall | 5,889 | 50.3 | |
| Characteristics: | |||
| Age | |||
| 80–84 | 3,377 | 65.1 | 1.0 |
| 85–89 | 1,754 | 38.1 | 0.7 (0.6–0.7) |
| 90+ | 758 | 12.7 | 0.3 (0.2–0.3) |
| Metropolitan status of residence | |||
| Metropolitan | 5,444 | 52.0 | 1.0 |
| Non-Metropolitan | 445 | 29.3 | 0.8 (0.7–0.9) |
| Race/Ethnicity | |||
| Non-Hispanic White | 5,439 | 50.2 | 1.0 |
| Non-Hispanic Black | 218 | 48.2 | 1.0 (0.9–1.2) |
| Hispanic | 47 | 44.7 | 0.8 (0.6–1.1) |
| Asian | 90 | 68.9 | 1.1 (0.9–1.3) |
| Other | 61 | 52.5 | 0.9 (0.7–1.2) |
| Unknown | 34 | 35.3 | 0.8 (0.6–1.1) |
| Marital status | |||
| Not currently married | 4,240 | 46.8 | 1.0 |
| Currently married | 1,444 | 62.6 | 1.1 (1.0–1.1) |
| Unknown | 203 | 36.0 | 0.8 (0.7–0.9) |
| Year of diagnosis | |||
| 92–95 | 1,310 | 38.5 | 1.0 |
| 96–00 | 2,141 | 50.7 | 1.2 (1.1–1.3) |
| 01–05 | 2,438 | 56.2 | 1.2 (1.1–1.3) |
| Median income for area of residence | |||
| Lowest Quintile | 1,020 | 42.6 | 1.0 |
| 2nd Quintile | 1,156 | 47.7 | 1.0 (0.9–1.1) |
| 3rd Quintile | 1,205 | 50.0 | 1.0 (0.9–1.1) |
| 4th Quintile | 1,228 | 52.9 | 1.0 (0.9–1.2) |
| 5th Quintile | 1,254 | 57.1 | 1.1 (1.0–1.3) |
| Quintiles of education (<12 years) for those Age ≥ 25 in area of residence | |||
| Lowest Quintile | 976 | 45.2 | 1.0 |
| 2nd Quintile | 1,070 | 49.7 | 1.1 (1.0–1.1) |
| 3rd Quintile | 1,220 | 48.9 | 1.1 (1.0–1.2) |
| 4th Quintile | 1,274 | 52.9 | 1.1 (1.0–1.2) |
| 5th Quintile | 1,323 | 53.7 | 1.1 (1.0–1.2) |
| Mammography Use | |||
| Screeners | 2,846 | 63.0 | 1.0 |
| Non-users | 1,955 | 37.8 | 0.8 (0.8–0.9) |
| Peri-diagnosis | 814 | 35.9 | 0.8 (0.7–0.8) |
| Other | 274 | 50.0 | 0.9 (0.8–1.0) |
| Tumor stage | |||
| Stage I | 3,733 | 59.5 | 1.0 |
| Stage II | 842 | 46.2 | 1.0 (0.9–1.2) |
| Unknown | 1,314 | 26.8 | 0.8 (0.6–1.2) |
| Tumor Grade | |||
| Grade I | 1,740 | 50.6 | 1.0 |
| Grade II | 2,582 | 52.0 | 1.1 (1.0–1.1) |
| Grade III | 1,030 | 50.5 | 1.1 (1.0–1.2) |
| Grade IV | 56 | 57.1 | 1.4 (1.1–1.7) |
| Unknown | 481 | 38.5 | 1.0 (0.9–1.1) |
| Tumor size | |||
| ≤1cm | 2,477 | 55.6 | 1.0 |
| 1–≤2cm | 2,387 | 50.6 | 1.0 (1.0–1.1) |
| 2-≤5cm | 1,025 | 36.8 | 0.9 (0.8–1.1) |
| Tumor histology | |||
| Ductal | 4,568 | 50.8 | 1.0 |
| Lobular | 446 | 55.8 | 1.0 (0.9–1.1) |
| Mucinous | 417 | 47.5 | 1.0 (0.9–1.1) |
| Other | 436 | 41.7 | 0.8 (0.8–0.9) |
| Lymph node | |||
| None positive | 4,604 | 57.0 | 1.0 |
| None examined | 1,285 | 26.4 | 0.7 (0.5–1.0) |
| SEER registry | |||
| Connecticut | 1,031 | 52.4 | 1.0 |
| San Francisco | 548 | 51.1 | 1.0 (0.9–1.0) |
| Detroit | 740 | 52.2 | 1.0 (1.0–1.1) |
| Hawaii | 91 | 69.2 | 1.1 (0.9–1.3) |
| Iowa | 847 | 33.3 | 0.8 (0.7–0.9) |
| New Mexico | 166 | 50.0 | 1.0 (0.9–1.2) |
| Seattle | 791 | 56.5 | 1.1 (1.0–1.2) |
| Utah | 246 | 56.9 | 1.2 (1.0–1.3) |
| Atlanta | 294 | 41.5 | 0.8 (0.7–0.9) |
| San Jose | 235 | 52.3 | 1.0 (0.9–1.1) |
| Los Angeles | 900 | 55.0 | 1.0 (0.9–1.1) |
| Comorbidities | |||
| Dementia | 173 | 9.8 | 0.3 (0.2–0.4) |
| Nutrition Deficiencies | 88 | 26.1 | 0.7 (0.5–1.0) |
| Heart Failure | 812 | 33.4 | 0.8 (0.7–0.9) |
| Mood Disorder | 378 | 38.4 | 0.8 (0.7–0.9) |
| Other Cancer | 267 | 44.6 | 0.8 (0.7–0.9) |
| Peptic Ulcer Disease | 111 | 36.9 | 0.8 (0.7–1.1) |
| Hip fracture | 133 | 27.8 | 0.8 (0.6–1.0) |
| Parkinson’s Disease | 75 | 33.3 | 0.9 (0.6–1.2) |
| COPD | 667 | 45.9 | 0.9 (0.8–1.0) |
| Cerebral Vascular Disease | 547 | 39.7 | 0.9 (0.8–1.0) |
| Pneumonia | 248 | 32.7 | 0.9 (0.8–1.1) |
| Peripheral Vascular Disease | 292 | 39.4 | 0.9 (0.8–1.1) |
| Chronic Renal Failure | 90 | 42.2 | 0.9 (0.7–1.1) |
| Gastrointestinal Hemorrhage | 234 | 43.2 | 1.0 (0.8–1.1) |
| Thyroid Disorder (not cancer) | 916 | 51.5 | 1.0 (0.9–1.1) |
| Falls | 129 | 37.2 | 1.0 (0.8–1.3) |
| Diabetes | 823 | 50.7 | 1.0 (1.0–1.1) |
| Rheumatologic Disorders | 160 | 55.6 | 1.1 (0.9–1.2) |
| Blindness | 289 | 53.3 | 1.1 (1.0–1.2) |
| Hypertension | 3,471 | 52.4 | 1.0 (1.0–1.1) |
| Myocardial infarction | 217 | 46.5 | 1.1 (1.0–1.3) |
| Charlson Comorbidity Index ‡ | |||
| 0 | 3,223 | 55.4 | 1.0 |
| 1 | 1,402 | 46.2 | 0.9 (0.8–0.9) |
| 2 | 743 | 45.4 | 0.9 (0.8–0.9) |
| 3+ | 521 | 36.9 | 0.7 (0.7–0.8) |
Each model was adjusted for tumor characteristics (grade, tumor size, histology, stage), sociodemographics at diagnosis (age, marital status, race/ethnicity, educational attainment of census tract, ZIP code, median household income of census tract/income, metropolitan status of residence), year of diagnosis, lymph node status, mammography use, and tumor registry.
Odds ratios were converted to Relative Risks using SAS PROC GENMOD’s Poisson regression capability.
In a separate model, we categorized women by their Charlson Comorbidity Index (0,1,2,3+) rather than their individual comorbidities; however, we did include conditions from the Clinical Classifications Software that were not included in the Charlson.