Table 1.
Volunteer Characteristics at Baseline
| Non-Converters (N=3,644) | Converters (N=873) | t or χ2 Statistica | |
|---|---|---|---|
| Age (yrs) | 73.79 (7.78)b | 77.97 (7.95) | −14.01, df=1301.28, p<0.001 |
| Female | 2,429 (67%)c | 525 (60%) | 13.23, df=1, p<0.001 |
| Education (yrs) | 15.61 (3.03) | 15.26 (3.26) | 2.92, df=1249.18, p=0.004 |
| Race | |||
| White | 2950 (81%) | 742 (85%) | 8.52, df=2 p=0.014 |
| African American | 592 (16%) | 116 (13%) | |
| Other | 102 (3%) | 15 (2%) | |
| MMSE | 28.93 (1.41) | 28.46 (1.66) | 7.48, df=1150.15, p<0.001 |
| NPI-Q | 0.67 (1.53) | 1.26 (2.61) | −6.43, df=1018.60, p<0.001 |
| GDS | 1.13 (1.79) | 1.68 (2.27) | −6.68, df=1134.30, p<0.001 |
| Depression (last two years) | 567 (16%) | 186 (21%) | 16.79, df=1, p<0.001 |
| Depression (past) | 576 (16%) | 103 (12%) | 8.88, df=1, p=0.003 |
| Current Use of Antidepressant | 481 (13%) | 144 (16%) | 6.41, df=1, p=0.011 |
| Number of Visits | 4.16 (1.87) | 4.67 (1.73) | −7.68, df=1402.73, p<0.001 |
| Follow-up (yrs) | 3.63 (2.00) | 4.21 (1.81) | −8.33, df=1421.02, p<0.001 |
Abbreviations: MMSE – Mini-Mental Status Examination; NPI-Q - Neuropsychiatric Inventory-Q; GDS – Geriatric Depression Scale (15-item)
a
χ2 test statistics are presented for categorical variables, t test statistics for continuous variables.
b
Continuous variables are described with mean (SD)
c
Categorical variables are described with number (%).