Table 3.
Adherence (Medication Possession Ration >80%) of patients diagnosed with localized breast cancer at age 50 years or older who received adjuvant hormonal therapy*
| Categories | Unadjusted frequencies | Multivariable analysis | ||
|---|---|---|---|---|
| Adhered | Nonadhered | OR (95% CI) | P | |
| No. (%) | No. (%) | |||
| Total | 3176 (75.1) | 1050 (24.8) | ||
| Type of therapy | ||||
| AI-brand | 1996 (70.9) | 819 (29.1) | 1.0 (reference) | |
| AI-generic | 1180 (83.6) | 231 (16.4) | 1.53 (122 to 1.91) | <.001 |
| Prescription coverage characteristics | ||||
| Adjusted 30-day copay | ||||
| <$15 | 1380 (82.8) | 286 (17.2) | 1.0 (reference) | |
| $15-$30 | 1012 (75.0) | 338 (25.0) | 0.74 (0.59 to 0.92) | .008 |
| >$30 | 784 (64.8) | 426 (35.2) | 0.51 (0.41 to 0.65) | <.001 |
| Pharmacy deductible type | ||||
| No deductible | 1858 (77.7) | 1038 (22.3) | 1.0 (reference) | |
| Pharmacy deductible only | 169 (72.2) | 123 (27.8) | 0.81 (0.59 to 1.10) | .17 |
| Shared pharmacy/medical deductible | 144 (77.8) | 94 (22.2) | 0.87 (0.60 to 1.27) | .48 |
| Coverage type | ||||
| Commercial | 2885 (77.2) | 854 (22.8) | 1.0 (reference) | |
| Medicare | 291 (59.7) | 196 (40.2) | 0.52 (0.38 to 0.72) | <.001 |
| Clinical characteristics | ||||
| Provider specialty (most common prov) | ||||
| Primary care/other | 819 (76.1) | 257 (23.9) | 1.0 (reference) | |
| Hematology/oncology | 2357 (74.8) | 793 (25.2) | 0.95 (0.80 to 1.12) | .55 |
| Surgery | ||||
| Lumpectomy/other | 1463 (75.2) | 483 (24.8) | 1.0 (reference) | |
| Mastectomy | 1713 (75.1) | 567 (24.9) | 1.10 (0.95 to 1.27) | .19 |
| Comorbidities (used ETG score) | ||||
| 1–5 | 2573 (75.9) | 817 (24.1) | 1.0 (reference) | |
| 6+ | 603 (72.1) | 233 (27.9) | 0.78 (0.65 to 0.93) | .007 |
| Age at diagnosis, y | ||||
| 50–55 | 539 (75.0) | 180 (25.0) | 0.86 (0.71 to 1.06) | .17 |
| 56–65 | 1842 (77.4) | 537 (22.6) | 1.0 (reference) | |
| 66–75 | 555 (76.2) | 173 (23.8) | 1.24 (0.99 to 1.57) | .06 |
| 75+ | 240 (60.0) | 160 (40.0) | 0.67 (0.51 to 0.88) | .004 |
| Sociodemographic characteristics | ||||
| Race/ethnicity | ||||
| White | 1965 (77.7) | 565 (22.3) | 1.0 (reference) | |
| Black | 230 (73.7) | 82 (26.3) | 0.93 (0.69 to 1.24) | .55 |
| Hispanic | 154 (71.0) | 63 (29.0) | 1.15 (0.72 to 1.85) | .55 |
| Asian | 61 (81.3) | 14 (18.7) | 1.98 (0.99 to 3.96) | .05 |
| Other/unknown race | 766 (70.0) | 326 (29.9) | 0.64 (0.44 to 0.93) | .02 |
| Education | ||||
| High school or less | 691 (75.0) | 431 (25.0) | 1.0 (reference) | |
| More than high school | 2485 (75.2) | 1542 (24.8) | 0.92 (0.75 to 1.13) | .44 |
| Household income | ||||
| Low (<$40000) | 504 (71.9) | 197 (28.1) | 1.0 (reference) | |
| Middle ($40K-$100K) | 1409 (76.8) | 426 (23.2) | 1.19 (0.95 to 1.49) | .12 |
| High (>$100K) | 546 (81.0) | 128 (19.0) | 1.58 (1.17 to 2.11) | .002 |
| Unknown | 717 (70.6) | 299 (29.4) | 1.52 (0.99 to 2.32) | .06 |
| Region | ||||
| Northeast | 600 (80.6) | 144 (19.3) | 1.0 (reference) | |
| West | 617 (69.5) | 271 (30.5) | 0.70 (0.53 to 0.93) | .01 |
| Midwest | 709 (79.6) | 182 (20.4) | 0.88 (0.67 to 1.17) | .38 |
| South | 1249 (73.5) | 450 (26.5) | 0.71 (0.55 to 0.91) | .006 |
* AI-brand = brand name aromatase inhibitor; AI-generic = generic aromatase inhibitor; CI = confidence interval; ETG = episode treatment group.