Impact of Undetected Comorbidity on Treatment and Outcomes of Breast Cancer

Table 3

Adjuvant chemotherapy.

	OR	95% CI		𝑃 value
		Lower	Upper
Age at cancer diagnosis (years)
66–70	Reference category
71–75	0.55	0.51	0.59	<0.0001
76–80	0.25	0.23	0.27	<0.0001
>80	0.05	0.04	0.05	<0.0001
Race/ethnicity
White	Reference category
Black	0.94	0.84	1.05	0.27
Hispanic	1.15	0.99	1.32	0.06
Other	1.13	0.98	1.31	0.10
Year of cancer diagnosis
2001	Reference category
2002	0.95	0.87	1.04	0.26
2003	0.86	0.79	0.94	<0.001
2004	0.88	0.80	0.96	<0.01
2005	0.79	0.72	0.86	<0.0001
Index of prior comorbidity score (NCI Comorbidity Index)
0	Reference category
1	0.96	0.90	1.03	0.28
≥2	0.74	0.66	0.82	<0.0001
Index of undetected comorbidity score
0	Reference category
1	0.81	0.73	0.90	<0.0001
≥2	0.38	0.30	0.49	<0.0001
Indicators of poor performance
0	Reference category
≥1	0.56	0.51	0.62	<0.0001
Stage at diagnosis
I	Reference category
II	8.73	8.17	9.34	<0.0001
III	21.87	19.83	24.12	<0.0001
Histological grade
Well differentiated	Reference category
Moderately differentiated	1.58	1.44	1.72	<0.0001
Poorly differentiated	2.54	2.31	2.79	<0.0001
Undifferentiated/anaplastic	2.01	1.60	2.53	<0.0001
Missing/unknown	1.51	1.33	1.71	<0.0001
Estrogen (ER) and progesterone (PR) receptor status
ER and PR negative	Reference category
Either ER or PR positive	0.32	0.29	0.35	<0.0001
Both ER and PR positive	0.24	0.22	0.26	<0.0001
Unknown/missing	0.30	0.27	0.34	<0.0001
Percent in census tract with some college
<25%	Reference category
≥25%	1.02	0.95	1.08	0.65
Percent in census tract living in poverty
<5%	Reference category
5–7%	0.93	0.85	1.02	0.13
8–12%	0.93	0.86	1.01	0.08
>12%	0.91	0.84	0.98	0.01
Type of geographic area
Large metropolitan	Reference category
Metropolitan	1.12	1.05	1.20	<0.01
Urban	1.14	1.01	1.29	0.03
Less urban/rural	1.06	0.95	1.18	0.32

OR: Odds Ratio; CI: Confidence Interval.