Table 1.
Baseline characteristics of patients with early colon cancer 66 years or older at diagnosis, enrolled in part A and B of Medicare, not in a HMO and with a complete staging(N=36,291).
| Not receiving any duplicate scan(N=33,611) |
Receiving at least one duplicate scan(N=2,680) |
|
|---|---|---|
| Sentinel symptom(%) | ||
| Anemia | 26,007(77) | 2,202(82) |
| Gastrointestinal symptoms1 | 15,194(45) | 1,540(57) |
| Large bowel obstruction | 6,993(21) | 794(30) |
| Abnormal weight loss | 5,775(17) | 629(23) |
| Asthenia | 14,015(42) | 1,391(52) |
| Comorbidity score(%) | ||
| 0 | 17,645(53) | 1,117(42) |
| 1 | 8,514(25) | 717(27) |
| 2+ | 6,121(18) | 743(28) |
| Unknown | 1,331(4) | 103(4) |
| Median age when staged(range) | 78.4(65.9–106.3) | 78.6(65.8–99.2) |
| Female(%) | 19,620(58) | 1,564(58) |
| Race(%) | ||
| Caucasian NOS | 27,947(83) | 2,171(81) |
| Caucasian, Spanish origin or surname | 1,384(4) | 117(4) |
| African American | 2,590(8) | 250(9) |
| Asian/Pacific islander | 1,526(5) | 131(5) |
| Other/Unknown/unspecified | 164(0) | 11(0) |
| Stage(%) | ||
| I | 8,623(25) | 671(25) |
| II | 14,449(43) | 1,088(41) |
| III | 10,899(32) | 921(34) |
| Grade of differentiation(%) | ||
| Well differentiated | 2,711(8) | 201(8) |
| Moderately differentiated | 22,841(68) | 1,749(65) |
| Poorly differentiated | 6,907(21) | 589(22) |
| Unknown | 1,152(3) | 141(5) |
| Median number of low complexity visits(Q1–Q3)2 | 7(2–13) | 7(3–15) |
| Median preventive score(Q1–Q3)3 | 2(1–3) | 2(1–3) |
| Urbanicity(%) | ||
| Big Metro (≥1 million population) | 19,361(58) | 1,595(60) |
| Metro (250,000 to 1 million) | 9,135(27) | 650(24) |
| Urban (20,000 to 250,000) | 1,821(5) | 127(5) |
| Less Urban (2,500 to 20,000) | 2,672(8) | 246(9) |
| Rural (rural or < 2,500 population) | 622(2) | 62(2) |
| Marital Status(%) | ||
| Single | 2,593(8) | 219(8) |
| Married | 16,168(48) | 1,176(44) |
| Separated/divorced | 2,059(6) | 173(6) |
| Widowed | 11,446(34) | 1,021(38) |
| Unknown | 1,345(4) | 101(4) |
| SEER registry census region(%) | ||
| West | 11,309(34) | 867(32) |
| Northeast | 9,897(29) | 809(30) |
| Midwest | 5,203(15) | 395(15) |
| South | 6,741(20) | 588(22) |
| Pacific | 461(1) | 21(1) |
| Year of diagnosis(%) | ||
| 1996–2000 | 5,580(17) | 318(12) |
| 2001–2005 | 15,812(47) | 1,184(44) |
| 2006–2009 | 12,219(36) | 1,178(44) |
| Census tract features4[median(Q1–Q3)] | ||
| % did not complete high school | 15.7(9.4–25.5) | 17.1(10.4–27.5) |
| % below poverty line | 7.6(4.1–14.3) | 8.2(4.4–15.9) |
| % black race/ethnicity | 2.1(0.6–7.7) | 2.4(0.7–9.5) |
| % English not well/at all at 65+ | 1.6(0–5.5) | 1.5(0–5.8) |
| Median income(USD) | 46,163(34,742–61,152) | 44,712(33,099–60,007) |
1
Gastrointestinal symptoms include abdominal distention, change in bowel habit, constipation, irritable bowel syndrome, diarrhea, obstruction, anemia, abnormal weight loss, asthenia.
2
Low complexity visits(as defined by CPT codes, see appendix Table A1) during the years -2 and -3 of diagnosis.
3
See methods section for details.
4
Census tract features are missing for 218 individuals