Table 1.
Demographic and Oil-Spill Work Characteristics at Enrollment (Except Where Noted) Among Those Who Completed (n = 16,814) and Did Not Complete (n = 7,561) the Second Study Interview, Gulf Long-Term Follow-up Study, United States, 2010–2016
| Characteristic | Completed Interview 2 (n = 16,814) | Did Not Complete Interview 2 (n = 7,561) | RD | 95% CI | ||
|---|---|---|---|---|---|---|
| No. | % | No. | % | |||
| Sex | ||||||
| Male | 13,747 | 81.8 | 6,335 | 83.8 | 0 | Referent |
| Female | 3,067 | 18.2 | 1,226 | 16.2 | 0.0299 | 0.0149, 0.0448 |
| Missing | 0 | 0.0 | 0 | 0.0 | ||
| Age category, years | ||||||
| 20–29 | 2,936 | 17.5 | 2,063 | 27.4 | −0.0489 | −0.0673, −0.0306 |
| 30–39 | 3,745 | 22.3 | 2,141 | 28.4 | 0 | Referent |
| 40–49 | 4,245 | 16.8 | 1,726 | 7.6 | 0.0747 | 0.0579, 0.0915 |
| 50–59 | 4,018 | 16.8 | 1,188 | 5.5 | 0.1355 | 0.1188, 0.1523 |
| 60–65 | 1,071 | 4.6 | 256 | 1.3 | 0.1708 | 0.1463, 0.1954 |
| ≥65 | 753 | 3.4 | 153 | 0.9 | 0.1949 | 0.1676, 0.2222 |
| Missing | 46 | 0.3 | 34 | 0.4 | ||
| Ethnicity | ||||||
| White | 11,270 | 67.4 | 4,827 | 64.2 | 0 | Referent |
| Black | 3,767 | 22.5 | 1,859 | 24.7 | −0.0306 | −0.0447, −0.0164 |
| Asian | 132 | 0.8 | 87 | 1.2 | −0.0974 | −0.1626, −0.0322 |
| Other/multiracial | 1,554 | 9.3 | 743 | 9.9 | −0.0236 | −0.044, −0.0032 |
| Missing | 91 | 0.5 | 45 | 0.6 | ||
| Hispanic | ||||||
| Yes | 1,112 | 6.6 | 599 | 7.9 | −0.0431 | −0.0664, −0.0197 |
| No | 15,659 | 93.4 | 6,938 | 92.1 | 0 | Referent |
| Missing | 43 | 0.3 | 24 | 0.3 | ||
| Education completed | ||||||
| Less than high school | 2,446 | 14.6 | 1,376 | 18.3 | −0.0129 | −0.0317, 0.0059 |
| High-school diploma/GED | 4,673 | 27.9 | 2,485 | 33.0 | 0 | Referent |
| Some college/2-year degree | 5,032 | 30.0 | 2,269 | 30.1 | 0.0364 | 0.0211, 0.0517 |
| ≥4-year college graduate | 4,618 | 27.5 | 1,408 | 18.7 | 0.1135 | 0.0982, 0.1289 |
| Missing | 45 | 0.3 | 23 | 0.3 | ||
| 2010 household income, $ | ||||||
| ≤20,000 | 3,960 | 25.9 | 2,114 | 31.3 | −0.0208 | −0.0370, −0.0045 |
| 20,001–50,000 | 4,748 | 31.1 | 2,310 | 34.2 | 0 | Referent |
| >50,000 | 6,581 | 43.0 | 2,330 | 34.5 | 0.0658 | 0.0516, 0.0801 |
| Missing | 1,525 | 9.1 | 807 | 10.7 | ||
| Residential proximity to the spilla | ||||||
| Direct/indirect | 9,688 | 57.6 | 4,723 | 62.5 | −0.0429 | −0.0546, −0.0312 |
| Away from the spill | 7,126 | 42.4 | 2,838 | 37.5 | 0 | Referent |
| Missing | 0 | 0.0 | 0 | 0.0 | ||
| Cleanup work duration, days | ||||||
| 1–30 | 2,063 | 12.3 | 935 | 12.4 | 0 | Referent |
| 31–90 | 5,293 | 31.5 | 2,376 | 31.4 | 0.0021 | −0.0175, 0.0216 |
| 91–180 | 5,735 | 43.8 | 2,628 | 44.2 | −0.0024 | −0.0217, 0.0170 |
| >180 | 3,723 | 22.1 | 1,622 | 21.5 | 0.0084 | −0.0122, 0.0291 |
| Missing | 0 | 0.0 | 0 | 0.0 | ||
| Worked before the well was capped | ||||||
| Yes | 15,453 | 94.0 | 7,097 | 94.8 | −0.0321 | −0.0567, −0.0076 |
| No | 985 | 6.0 | 388 | 5.2 | 0 | Referent |
| Missing | 0 | 0.0 | 0 | 0.0 | ||
| Maximum total hydrocarbon exposure, ppm | ||||||
| <0.30 | 3,864 | 23.0 | 1,579 | 20.9 | 0 | Referent |
| 0.30–0.99 | 5,519 | 32.9 | 2,465 | 32.6 | −0.0186 | −0.0344, −0.0029 |
| 1.00–2.99 | 5,094 | 30.3 | 2,382 | 31.5 | −0.0285 | −0.0446, −0.0125 |
| ≥3.00 | 2,313 | 13.8 | 1,132 | 15.0 | −0.0385 | −0.0583, −0.0187 |
| Missing | 24 | 0.1 | 3 | 0.0 | ||
| Reported ever having had a nonfatal MI | ||||||
| Yes | 416 | 2.5 | 126 | 1.7 | 0.0795 | 0.0434, 0.1155 |
| No | 16,350 | 97.5 | 7,413 | 98.3 | 0 | Referent |
| Missing | 48 | 0.3 | 22 | 0.3 | ||
| First nonfatal MI/fatal CHD occurring after initiation of oil spill work | ||||||
| Yes | 250 | 1.5 | 62 | 0.8 | 0.1156 | 0.0710, 0.1603 |
| No | 16,125 | 98.5 | 7,392 | 99.2 | 0 | Referent |
| Missing | 439 | 2.6 | 107 | 1.4 | ||
| Self-reported physician-diagnosed hypertension before study enrollment | ||||||
| Yes | 4,716 | 28.1 | 1,701 | 22.6 | 0.0613 | 0.0485, 0.0741 |
| No | 12,053 | 71.9 | 5,839 | 77.4 | 0 | Referent |
| Missing | 45 | 0.3 | 21 | 0.3 | ||
| Perceived health | ||||||
| Excellent | 2,689 | 16.1 | 1,279 | 17.0 | −0.0130 | −0.0308, 0.0048 |
| Very good | 5,383 | 32.2 | 2,350 | 31.3 | 0.0054 | −0.0091, 0.0200 |
| Good | 5,352 | 32.0 | 2,397 | 31.9 | 0 | Referent |
| Fair | 2,471 | 14.8 | 1,132 | 15.1 | −0.0049 | −0.0232, 0.0135 |
| Poor | 841 | 5.0 | 360 | 4.8 | 0.0096 | −0.0183, 0.0375 |
| Missing | 78 | 0.5 | 43 | 0.6 | ||
| Tobacco smoking | ||||||
| Current | 4,710 | 28.2 | 2,635 | 35.2 | −0.0681 | −0.0818, −0.0544 |
| Former | 3,713 | 22.2 | 1,452 | 19.4 | 0.0095 | −0.0052, 0.0243 |
| Never | 8,300 | 49.6 | 3,401 | 45.4 | 0 | Referent |
| Missing | 91 | 0.5 | 73 | 1.0 | ||
| Current alcohol use | ||||||
| Yes | 12,852 | 76.9 | 5,677 | 75.7 | 0.0135 | −0.0003, 0.0274 |
| No | 3,871 | 23.1 | 1,821 | 24.3 | 0 | Referent |
| Missing | 91 | 0.5 | 63 | 0.8 | ||
| BMIb at enrollment | ||||||
| <25.0 | 4,365 | 26.2 | 2,140 | 28.7 | 0 | Referent |
| 25.0–29.9 | 6,911 | 41.5 | 3,078 | 41.3 | 0.0208 | 0.0063, 0.0354 |
| ≥30.0 | 5,365 | 32.2 | 2,236 | 30.0 | 0.0348 | 0.0195, 0.0501 |
| Missing | 173 | 1.0 | 107 | 1.4 | ||
Abbreviations: BMI, body mass index; CHD, coronary heart disease; CI, confidence interval; GED, General Educational Development; MI, myocardial infarction; ppm, parts per million; RD, risk difference.
a Residential proximity to the spill is defined as living in, or adjacent to, a county with coastline that was oiled during the spill.
b BMI defined as weight (kg)/height (m)2.