Descriptive statistics of the study population.
| Group 1 | Group 2 | Combined | ||||
|---|---|---|---|---|---|---|
| Progressors, n = 57) | Nonprogressors, n = 206 | Progressors, n = 177 | Nonprogressors, n = 116 | Progressors, n = 234 | Nonprogressors, n = 322 | |
| Age, yrs | 62.6 ± 7.6 | 61.8 ± 7.4 | 63.5 ± 7.6 | 63.9 ± 8.2 | 63.3 ± 7.6 | 62.6 ± 7.8 |
| Sex, % female | 56.1 | 56.8 | 66.1 | 71.6 | 63.7 | 62.1 |
| BMI, kg/m2† | 32.1 ± 5.3∗ | 30.0 ± 5.8 | 33.1 ± 6.7 | 32.8 ± 5.9 | 32.8 ± 6.4∗ | 31.0 ± 6.0 |
| Race, % white | 98.3 | 99.0 | 98.3 | 99.1 | 98.3 | 99.1 |
| Iowa clinic site, % | 54.4 | 51.5 | 46.3 | 56.0 | 48.3 | 53.1 |
| Group 2, %§ | – | – | – | – | 75.6∗ | 36.0 |
↵∗Statistical testing was done with chi-square or t test wherever appropriate.
↵† BMI at baseline was significantly higher in cases than controls in group 1 with P = 0.01, and in combined analysis with P = 0.0005. Group 2 had a significantly higher number of cases in the combined analysis with P < 0.0001.