Table 2.
Weighted estimates of ANA prevalence for selected characteristics by time period.
| Weighted Estimate of ANA Prevalence (95% CI) as a Percentage a | |||
|---|---|---|---|
| Characteristic b | Period 1: 1988-1991 | Period 2: 1999-2004 | Period 3: 2011-2012 |
| Overall | 11.0 ( 9.7 - 12.6) | 11.5 (10.3 - 12.8) | 15.9 (14.3 - 17.6) |
| Sex | |||
| Male | 6.5 ( 5.2 - 8.0) | 6.1 ( 5.0 - 7.5) | 11.4 ( 9.6 - 13.5) |
| Female | 15.3 (13.1 - 17.7) | 16.4 (14.5 - 18.6) | 20.1 (17.9 - 22.5) |
| Age (years) | |||
| Adolescent (12-19) | 5.0 ( 3.1 - 7.9) | 9.4 ( 7.3 - 12.1) | 12.8 ( 9.8 - 16.6) |
| Younger Adult (20-49) | 10.3 ( 8.6 - 12.3) | 9.2 ( 7.7 - 11.0) | 13.0 (11.0 - 15.3) |
| Older Adult ( ≥ 50 ) | 15.3 (13.1 - 17.8) | 15.8 (12.8 - 19.3) | 20.5 (18.0 - 23.3) |
| Race/Ethnicity | |||
| Non-Hispanic White | 10.2 ( 8.6 - 12.0) | 11.2 ( 9.6 - 12.9) | 16.4 (14.2 - 18.8) |
| Non-Hispanic Black | 15.0 (13.4 - 16.7) | 14.7 (12.4 - 17.4) | 18.1 (15.0 - 21.7) |
| Mexican-American | 13.6 (11.5 - 16.0) | 12.0 ( 9.8 - 14.7) | 12.3 (10.1 - 15.0) |
| Other | 12.0 ( 6.2 - 21.9) | 9.5 ( 6.9 - 13.0) | 14.0 (12.0 - 16.2) |
| Body Mass Index (BMI) | |||
| Underweight/Healthy | 11.4 ( 9.5 - 13.5) | 12.0 (10.4 - 13.8) | 14.2 (12.6 - 15.9) |
| Overweight | 9.5 ( 7.3 - 12.4) | 9.9 ( 8.0 - 12.1) | 16.7 (14.2 - 19.5) |
| Obese | 12.5 (10.1 - 15.4) | 12.5 (10.5 - 14.8) | 16.7 (13.4 - 20.5) |
| Smoking Exposure | |||
| None | 18.7 (12.6 - 26.8) | 13.4 (11.3 - 15.7) | 17.1 (14.3 - 20.2) |
| Second-Hand | 11.2 ( 9.5 - 13.2) | 12.6 (10.4 - 15.2) | 15.2 (13.2 - 17.5) |
| Active | 8.5 ( 6.2 - 11.5) | 7.5 ( 5.7 - 9.7) | 13.1 ( 10.9 - 15.8) |
| Alcohol Consumption | |||
| None | 15.3 (12.6 - 18.3) | 15.1 (11.9 - 19.0) | 21.3 (16.8 - 26.6) |
| Light | 12.2 ( 9.8 - 15.1) | 11.7 ( 9.7 - 14.0) | 16.1 (13.8 - 18.8) |
| Moderate/Heavy | 6.1 ( 4.3 - 8.6) | 6.2 ( 4.5 - 8.4) | 14.8 (11.6 - 18.7) |
Abbreviations: ANA = antinuclear antibodies; CI = confidence interval.
The weighted estimate of ANA prevalence was derived from a logistic regression model that adjusted for the survey design variables (strata, clusters, and sampling weights) and a categorical covariate for the characteristic of interest but not for other covariates. The estimated numbers of persons with ANA in the U.S. (with CI) in millions are: 22 (CI=19-25) for Period 1, 27 (CI=23-30) for Period 2, and 41 (CI=34-48) for Period 3.
BMI was categorized as underweight/healthy, overweight, or obese using standard cut points of <25, 25 to <30, or ≥30 kg/m2 for persons ≥20 years old and by applying 2000 CDC growth chart percentiles of <85, 85 to <95, or ≥95 for persons 12-19 years old. Smoking exposure was based on current measured cotinine levels and classified as none (<0.05 ng/ml), second-hand (0.05 to 15 ng/ml), or active (>15 ng/ml). Alcohol consumption (available for ages ≥20 years) was based on the number of drinks in the past year and classified as none (<12 total), light (1-3 per week), or moderate/heavy (>3 per week).