Table 2.
Sample Characteristics and Adjusted Likelihood of Chemotherapy and Radiation for Michigan Patients With Lung Cancer (N = 2,348)
| Characteristic | Medicare
|
Dually Eligible
|
P* | Chemotherapy
|
Radiation
|
||||
|---|---|---|---|---|---|---|---|---|---|
| No. | % | No. | % | OR | 95% CI† | OR | 95% CI† | ||
| Medicare | 2,087 | NA | 1.0 | Referent | 1.0 | Referent | |||
| Dually eligible | NA | 261 | 0.98 | 0.71 to 1.36 | 1.46 | 1.09 to 1.95‡ | |||
| Age, years | .0027 | ||||||||
| 66-69 | 481 | 23.05 | 82 | 31.42 | 1.0 | Referent | 1.0 | Referent | |
| 70-74 | 729 | 34.93 | 97 | 37.16 | 0.97 | 0.75 to 1.26 | 1.19 | 0.94 to 1.52 | |
| 75-79 | 512 | 24.53 | 59 | 21.61 | 0.87 | 0.66 to 1.16 | 1.46 | 1.12 to 1.89‡ | |
| ≥ 80 | 365 | 17.49 | 40 | 14.65 | 0.53 | 0.38 to 0.73‡ | 2.03 | 1.53 to 2.70‡ | |
| Race | < .001 | ||||||||
| White | 1,893 | 90.70 | 194 | 74.33 | 1.0 | Referent | 1.0 | Referent | |
| African American | 194 | 9.30 | 67 | 25.67 | 0.70 | 0.49 to 0.97‡ | 0.58 | 0.43 to 0.80‡ | |
| Sex | < .001 | ||||||||
| Male | 1,156 | 55.39 | 99 | 37.93 | 1.0 | Referent | 1.0 | Referent | |
| Female | 931 | 44.61 | 162 | 62.07 | 0.97 | 0.79 to 1.19 | 0.94 | 0.78 to 1.13 | |
| Comorbidity | < .001 | ||||||||
| 0 | 1,182 | 56.64 | 116 | 44.44 | 1.0 | Referent | 1.0 | Referent | |
| 1 | 558 | 26.74 | 86 | 32.95 | 0.95 | 0.75 to 1.20 | 1.02 | 0.82 to 1.25 | |
| 2+ | 347 | 16.63 | 59 | 22.61 | 0.86 | 0.65 to 1.14 | 1.34 | 1.05 to 1.72‡ | |
| Census tract median annual income, $ | < .001 | ||||||||
| < 35,000 | 1,182 | 56.64 | 209 | 80.08 | 1.09 | 0.87 to 1.37 | 0.97 | 0.79 to 1.19 | |
| ≥ 35,001 | 817 | 39.15 | 37 | 14.18 | 1.0 | Referent | 1.0 | Referent | |
| Missing | 88 | 4.22 | 15 | 5.75 | NA | NA | |||
| Urban/rural | .2107 | ||||||||
| Metropolitan | 1,625 | 77.86 | 188 | 72.03 | 1.0 | Referent | 1.0 | Referent | |
| Rural, adjacent to metropolitan | 8 | 0.38 | 0 | 0.00 | 0.93 | 0.18 to 4.88 | 0.81 | 0.41 to 1.62 | |
| Isolated rural | 38 | 1.82 | 5 | 1.92 | 0.46 | 0.20 to 1.04 | NA | ||
| Urban, not adjacent to metropolitan | 183 | 8.77 | 28 | 10.73 | 0.78 | 0.53 to 1.14 | 1.03 | 0.74 to 1.44 | |
| Urban, adjacent to metropolitan | 152 | 7.28 | 27 | 10.34 | 0.79 | 0.53 to 1.14 | 0.91 | 0.64 to 1.29 | |
| Missing | 81 | 3.88 | 13 | 4.98 | NA | NA | |||
| Cancer stage | .2869 | ||||||||
| I | 626 | 30.00 | 75 | 27.47 | 0.10 | 0.07 to 0.14‡ | 0.21 | 0.15 to 0.28‡ | |
| II | 1,012 | 48.49 | 118 | 45.21 | 0.24 | 0.18 to 0.32‡ | 0.42 | 0.32 to 0.56‡ | |
| IIIA | 218 | 10.45 | 29 | 11.11 | 1.39 | 0.96 to 1.52 | 1.89 | 1.29 to 2.77‡ | |
| IIIB | 231 | 11.07 | 39 | 14.94 | 1.0 | Referent | 1.0 | Referent | |
| Histology | .0915 | ||||||||
| Adenocarcinomas | 835 | 40.01 | 86 | 32.95 | 1.0 | Referent | 1.0 | Referent | |
| Large-cell carcinomas | 172 | 7.31 | 22 | 8.43 | 1.59 | 1.09 to 2.32 | 2.37 | 1.68 to 3.34‡ | |
| Others/unknown | 263 | 12.60 | 44 | 16.86 | 1.20 | 0.87 to 1.65 | 2.67 | 2.01 to 3.55‡ | |
| Squamous cell carcinomas | 825 | 39.53 | 109 | 41.76 | 1.10 | 0.87 to 1.40 | 2.10 | 1.71 to 2.59‡ | |
| Chemotherapy | 569 | 27.26 | 74 | 28.35 | .7109 | NA | NA | ||
| Radiation | 827 | 39.63 | 123 | 47.13 | .0207 | NA | NA | ||
Abbreviations: OR, odds ratio; NA, not applicable.
*
Rural, adjacent to a metropolitan area, and rural isolated were combined because few patients resided in a rural isolated area.
†
Statistical significance is determined by dividing the maximum likelihood coefficient by its standard error (Z) with two-tailed, statistical significance level set at P > Z.
‡
Statistically significant at P < .05.