Table 2.
Estimated U.S. Prevalence of ANA and Estimated Prevalence Odds Ratios for ANA Associations with BMI, Smoking Status, Alcohol Intake, and C-reactive Protein
| Characteristic | No.* | No.* ANA+ |
% ANA + (95% CI) |
Age-Adjusted POR (95% CI) |
|---|---|---|---|---|
| Total | 4754 | 670 | 13.8 (12.2–15.5) | |
| BMI‡,§,‖ | ||||
| Healthy | 1757 | 264 | 15.5 (12.8–18.2) | 1.00 (reference) |
| Underweight | 79 | 17 | 16.5 (6.6–26.5) | 1.11 (0.52–2.35) |
| Overweight | 1430 | 180 | 12.8 (10.3–15.3) | 0.74 (0.56–0.97) |
| Obese | 1370 | 188 | 12.6 (10.5–14.7) | 0.74 (0.59–0.94) |
| P Value† | 0.02 | |||
| Smoking status (cotinine), ng/mL | ||||
| No Detectable Smoke exposure, <0.015, 0.05¶ |
1246 | 191 | 14.5 (11.9–17.2) | 1.00 (reference) |
| Second-hand Smoke exposure, ≥ 0.05 –15¶ |
2439 | 349 | 14.4 (12.2–16.5) | 1.03 (0.81–1.31) |
| Active Smoking, >15 | 1040 | 125 | 12.2 (9.3–15.1) | 0.86 (0.64–1.16) |
| P Value† | 0.19 | |||
| Alcohol intake** | ||||
| Never and past | 1142 | 153 | 12.7 (9.9–15.6) | 1.00 (reference) |
| Current, light | 1473 | 232 | 15.9 (13.2–18.6) | 1.41 (0.99–2.00) |
| Current, moderate/heavy | 697 | 93 | 11.8 (8.7–14.9) | 1.02 (0.73–1.41) |
| P Value† | 0.73 | |||
| C-reactive protein, mg/L | ||||
| Low, <1 | 1625 | 221 | 13.7 (10.8–16.6) | 1.00 (reference) |
| Moderate, 1–3 | 1505 | 217 | 14.0 (11.3–16.6) | 0.92 (0.68–1.25) |
| High, >3–10 | 1176 | 164 | 13.5 (11.2–15.8) | 0.88 (0.64–1.19) |
| Very High, >10 | 448 | 68 | 14.9 (11.1–18.7) | 0.98 (0.70–1.38) |
| P Value† | 0.79 | |||
ANA = antinuclear antibodies; + = positive; POR = prevalence odds ratio; CI = confidence interval; BMI = body mass index.
No. reflects the number of subjects within the sample, not an estimated count for the US population.
P Value for the trend test investigates the linear association among ANA+ and levels of the population characteristics.
Body mass index was calculated as weight in kilograms divided by height in meters squared (kg/m2).
BMI categorization for children from birth to age 19 was based on the Centers for Disease Control and Prevention 2000 growth charts.
BMI categorization for adults age 20 and above was based on BMI values (kg/m2): Underweight (<18.5), Healthy (18.5 – <25.0), Overweight (25.0 – <30.0), Obese (≥30.0).
Cotinine detection limits (ng/mL) across the NHANES cycles were 0.05 (1999 – 2000), 0.015 and 0.05 (2001 – 2002), and 0.015 (2003 – 2004).
Alcohol use data for children 19 years old and younger was excluded from the analysis due to its restricted access to maintain confidentiality for these participants