Table 1.
Characteristics of Eligible Breast Cancer Patients Prescribed Aromatase Inhibitors During January 1, 2004–May 31, 2007
| Factor | (n=342) | n % |
|---|---|---|
| Age at AI start, years | ||
| <50 | 23 | 6.7 |
| 50–54 | 49 | 14.3 |
| 55–64 | 155 | 45.3 |
| 65+ | 115 | 33.6 |
| Race | ||
| Caucasian | 299 | 87.4 |
| African American | 14 | 4.1 |
| American Indian /Alaskan Native | 11 | 3.2 |
| Asian | 18 | 5.3 |
| Education | ||
| High school graduate or less | 50 | 14.6 |
| Some college | 88 | 25.7 |
| College graduate | 55 | 16.1 |
| Postcollege | 66 | 19.3 |
| Missing | 83 | 24.3 |
| Weight <70 kg (154 lbs)a | 201 | 58.7 |
| Smoking statusa | ||
| Current | 18 | 5.3 |
| Past | 80 | 23.4 |
| Never | 242 | 70.7 |
| Urban commuting area code | 334 | 97.7 |
| Insurance type | ||
| Medicare | 284 | 83.0 |
| Individual | 40 | 11.7 |
| Commercial | 18 | 5.3 |
| Primary care clinic geographic regiona | ||
| Region 1 (Seattle) | 169 | 49.4 |
| Region 2 (South) | 103 | 30.1 |
| Region 3 (West) | 17 | 5.0 |
| Region 4 (North) | 52 | 15.2 |
| Charlson comorbidity score | ||
| 0 | 246 | 71.9 |
| 1 | 64 | 18.7 |
| 2+ | 32 | 9.4 |
| History of fracture | 28 | 8.1 |
| Diabetes mellitus | 93 | 27.2 |
| Depression | 56 | 16.4 |
| Any medical conditions associated with osteoporosis (Appendix) | 20 | 5.9 |
| Corticosteroid use | 58 | 17.4 |
| Use of other medications associated with risk of osteoporosis (Appendix) | 72 | 21.1 |
| Incident breast cancer diagnosis year | ||
| 1990–1999 | 64 | 18.7 |
| 2000–2003 | 133 | 38.9 |
| 2004–2007 | 145 | 42.4 |
| Breast cancer stagea | ||
| I | 161 | 47.1 |
| IIA | 106 | 31.0 |
| IIB | 74 | 21.6 |
| Time from incident breast cancer diagnosis to AI start, years | ||
| ≤1 | 135 | 39.5 |
| >1–3 | 66 | 19.3 |
| >3–5 | 59 | 17.2 |
| >5–16 | 82 | 24.0 |
| AI start year | ||
| 2004 | 80 | 23.4 |
| 2005 | 129 | 37.7 |
| 2006 | 109 | 31.9 |
| 2007 | 24 | 7.0 |
| Duration of AI use during study period, years | ||
| <1 | 16 | 4.7 |
| 1–3 | 125 | 36.5 |
| >3 | 201 | 58.8 |
| Predominant type of AI usedb | ||
| Anastrozole | 193 | 56.4 |
| Exemestane | 31 | 9.1 |
| Letrozole | 118 | 34.5 |
| Tamoxifen (TAM) use since breast cancer diagnosis | ||
| No TAM use | 120 | 35.1 |
| TAM use before AI start | 203 | 59.3 |
| TAM use after AI | 19 | 5.6 |
| Number of visits to oncologist in year before starting AI | ||
| 0 | 47 | 13.7 |
| 1–2 | 164 | 48.0 |
| 3–4 | 70 | 20.5 |
| ≥5 | 61 | 17.8 |
| BMD test within 1 year before AI start | 56 | 16.3 |
a
Percentages calculated with missing as a separate category. Percent missing; weight 4.1%, smoking 0.6%, geographic region of clinic 0.3%, breast cancer stage 0.3%.
b
Aromatase inhibitor (AI) with longest days' supply.
BMD, bone mineral density.