Table 1.
Demographic and clinical data for the 224 participants with plasma samples collected using Protocol 1 that were analyzed using both MALDI-TOF-MS and LC-MS/MS platforms. Categorical variables are summarized using counts and percentages (%); continuous variables summarized using means and standard deviations (SD). MMSE, Mini-Mental State Exam; CFI, Cognitive Function Index
| Patient Demographic Data (n = 224) | ||||
| Characteristic | Aβ- | Aβ+ | Combined | |
| (N = 112) | (N = 112) | (N = 224) | ||
| APOE ɛ4 | Negative | 79 (35.27%) | 57 (25.45%) | 136 (60.71%) |
| Positive | 31 (13.84%) | 54 (24.11%) | 85 (37.95%) | |
| (Missing) | 2 (0.89%) | 1 (0.45%) | 3 (1.34%) | |
| Ethnicity | Hispanic or Latino | 3 (1.34%) | 1 (0.45%) | 4 (1.64%) |
| Not Hispanic or Latino | 108 (48.21%) | 110 (49.11%) | 218 (97.32%) | |
| (Missing) | 1 (0.45%) | 1 (0.45%) | 2 (0.89%) | |
| Race | American Indian or Alaska Native | 1 (0.45%) | 0 (0.00%) | 1 (0.45%) |
| Asian | 4 (1.79%) | 0 (0.00%) | 4 (1.79%) | |
| Black or African American | 8 (3.57%) | 0 (0.00%) | 8 (3.57%) | |
| White | 98 (43.75%) | 112 (50.00%) | 210 (93.75%) | |
| (Missing) | 1 (0.45%) | 0 (0.00%) | 1 (0.45%) | |
| Sex | Female | 71 (31.70%) | 57 (25.45%) | 128 (57.14%) |
| Male | 41 (18.30%) | 55 (24.55%) | 96 (42.86%) | |
| Age, mean (SD) | 72.08 (5.27) | 73.29 (4.86) | 72.69 (5.10) | |
| MMSE, mean (SD) | 28.83 (1.11) | 28.54 (1.43) | 28.69 (1.29) | |
| CFI, mean (SD) | 3.83 (3.82) | 3.97 (3.75) | 3.90 (3.78) | |
| Clinical Biomarker Summaries | ||||
| C2 N –Protocol 2 | Amyloid protein concentrations, mean (SD) | |||
| Aβ40 (pg/mL) | 508.07 (102.24) | 499.92 (69.44) | 504.00 (87.29) | |
| Aβ42 (pg/mL) | 47.15 (10.26) | 42.61 (6.49) | 44.88 (8.86) | |
| Aβ42/Aβ40 | 0.093 (0.008) | 0.085 (0.007) | 0.089 (0.009) | |
| Shimadzu –Protocol 2 | ||||
| Aβ40 (pg/mL) | 8.92 (2.61) | 8.31 (1.93) | 8.61 (2.31) | |
| Aβ42 (pg/mL) | 0.49 (0.14) | 0.40 (0.10) | 0.45 (0.13) | |
| Aβ42/Aβ40 | 0.055 (0.01) | 0.048 (0.01) | 0.052 (0.01) | |