Hospital Rurality and Gene Expression Profiling for Early-Stage Breast Cancer among Iowa Residents (2010–2018)
Table 4
Odds of receiving GEP testing among women with early-stage, HR+, HER2−, LN− breast cancer.
Unadjusted
Adjusted
OR (95% CI)
ORa (95% CI)
Hospital location
Urban
Ref
Ref
Large rural
0.86 (0.74–0.99)
1.05 (0.89–1.24)
Small rural
0.45 (0.36–0.57)
0.55 (0.43–0.71)
Age at diagnosis, years
<50
Ref
Ref
50–59
0.98 (0.83–1.16)
1.04 (0.88–1.23)
60–69
0.63 (0.54–0.74)
0.66 (0.56–0.78)
≥70
0.19 (0.16–0.22)
0.20 (0.17–0.24)
Marital status
Married/Living with partner
Ref
Ref
Otherb/Unknown
0.68 (0.62–0.76)
0.87 (0.77–0.97)
Insurance status
Insuredc
Ref
Ref
Any Medicaidd
1.27 (1.03–1.56)
1.00 (0.80–1.26)
Uninsured/Unknown
0.91 (0.70–1.17)
0.78 (0.59–1.03)
Median household income
<$50,000
Ref
Ref
$50,000-$59,999
1.18 (1.03–1.34)
1.15 (0.99–1.32)
$60,000-$69,999
1.25 (1.08–1.44)
1.17 (1.01–1.37)
≥$70,000
1.32 (1.15–1.51)
1.09 (0.94–1.32)
Year of diagnosis
2010–2012
Ref
Ref
2013–2015
1.04 (0.92–1.17)
1.00 (0.87–1.14)
2016–2018
1.43 (1.27–1.61)
1.47 (1.29–1.68)
Histology
Ductal
Ref
Ref
Lobular
1.05 (0.91–1.22)
1.15 (0.97–1.35)
Ductal + Lobular
1.29 (1.01–1.64)
1.29 (1.00–1.68)
Mucinous
0.40 (0.29–0.54)
0.53 (0.38–0.74)
NOS/Other
0.54 (0.43–0.68)
0.61 (0.48–0.78)
Tumor size, cm
0.6–1.9
Ref
Ref
2.0–4.0
1.34 (1.19–1.50)
1.29 (1.13–1.47)
>4.0
0.72 (0.54–0.97)
0.54 (0.39–0.75)
Tumor grade
Well differentiated
Ref
Ref
Moderately differentiated
1.59 (1.43–1.77)
1.61 (1.43–1.81)
Poorly differentiated/Undifferentiated
1.49 (1.29–1.73)
1.32 (1.12–1.56)
Unknown
0.84 (0.58–1.22)
0.79 (0.53–1.17)
Abbreviations: CI, confidence interval; CM, centimeter; GEP, gene expression profiling; HER2−, human epidermal growth factor receptor 2 negative; HR+, hormone receptor-positive; LN−, lymph node negative; NOS, not otherwise specified; OR, odds ratio; Ref, reference. Bold values indicate significance at α = 0.05. aAdjusted for all other variables in the table. bDivorced, separated, single, and widowed. c Private insurance and Medicare. d Indian Health Service. Bold values indicate significance at α = 0.05.
