Table 2. Odds Ratios Associated With CHD Cases Prior to Visit 4 for Selected Polygenic Risk Score Percentiles Among ARIC Participants.
| Polygenic Risk Scores | Odds Ratio (95% CI)a |
|---|---|
| Continuous per SD Increment | 1.89 (1.75-2.03) |
| Top percentilesb | |
| 20 | 2.89 (2.49-3.36) |
| 10 | 3.19 (2.64-3.84) |
| 5 | 4.14 (3.25-5.26) |
| 2 | 4.81 (3.32-6.93) |
Abbreviations: ARIC, Atherosclerosis Risk in Communities; CHD, coronary heart disease.
Odds ratios (95% CIs) are derived from logistic regression models adjusted for age, sex, and 5 principal components. Differences in allele frequencies between cases and controls due to systematic ancestral differences (population stratification) can cause spurious genetic associations. Such differences can be captured by principal components. The statistical models were adjusted for principal components to ensure that associations with the polygenic risk score were not attributable to such population stratification.
The odds ratios are the risk of a CHD diagnosis for individuals in the top percentile of the distribution compared with individuals in the remaining sample. For instance, participants in the top 20% of the polygenic risk score distribution are compared with individuals in the bottom 80%.