Table 5. The Prevalence of HLA-B27 for U.S. Adults Ages 20-69 Years, by Selected Characteristics, NHANES 2009*.
| Selected Characteristic | n | N | % | SE | 95% CI |
|---|---|---|---|---|---|
| Overall U.S. Prevalence | 124 | 2320 | 6.1 | 0.8 | (4.6-8.2) |
| Gender | |||||
| Males | 53 | 1123 | 5.8 | 1.0 | (3.9-8.4) |
| Females | 71 | 1197 | 6.5 | 1 | (4.7-8.9) |
| Race/Ethnic Groups | |||||
| Non-Hispanic Whites | 79 | 1021 | 7.5 | 1.2 | (5.3-10.4) |
| Mexican-Americans | 27 | 622 | 4.6 | 0.6 | (3.4-6.1) |
| Non-Hispanic Blacks | 4 | 345 | 1.1* | 0.5* | (0.4-3.1)* |
| Age Groups | |||||
| 20-29 Years | 39 | 498 | 8.0 | 2.0 | (4.6-13.4) |
| 30-39 years | 26 | 471 | 5.6 | 1.3 | (3.4-9.2) |
| 40-49 Years | 34 | 508 | 8.1 | 1.2 | (5.8-11.2) |
| 50-59 Years | 11 | 404 | 2.9** | 0.9** | (1.4-5.8)** |
| 60-69 Years | 14 | 439 | 4.6** | 1.9** | (1.9-10.7)** |
*
This is an estimate, as the small numbers lack statistical power to derive a definitive frequency
**
Multiple logistic regression analysis of the independent effects of gender, race/ethnicity and age group showed significantly lower HLA-B27 prevalence estimates for older as opposed to younger U.S. adults (3.6% for those 50-69 years of age vs. 7.3% for those 20-49 years, respectively (OR 0.4, 95% CI 0.3-0.8).