Table 1.
Participants’ baseline characteristics
| Men (N=214) | Women (N=261) | Sex difference | |||
|---|---|---|---|---|---|
| Mean (SD) or N (%) as noted | Range | Mean (SD) or N (%) | Range | p-value | |
| Demographics | |||||
| Age, years | 75.2 (8) | 60–94 | 73.9 (8.2) | 60–98 | 0.086 |
| Race and ethnicity, n (%) | |||||
| Chinese | 2 (0.9) | - | 4 (1.5) | - | - |
| Black | 34 (16) | - | 78 (30) | - | - |
| Filipino | 0 (0) | - | 3 (1.2) | - | - |
| Japanese | 0 (0) | - | 2 (0.8) | - | - |
| Other Asian or Other Pacific Islander | 3 (1.4) | - | 6 (2.3) | - | - |
| Other Non-White | 4 (1.9) | - | 0 (0) | - | - |
| White | 171 (80) | - | 167 (64) | - | - |
| Not Classifiable | 0 (0) | - | 1 (0.4) | - | - |
| Education, years | 18.3 (3.1) | 7–32 | 17.3 (2.7) | 12–24 | <0.001 |
| Waist circumference, cm | 95.7 (9.7) | 73–146.5 | 83.1 (11.1) | 56.4–111.2 | <0.001 |
| Brain Aging measures | |||||
| SPARE-BA score, unitless | 73.6 (10.8) | 46.2–99.7 | 72.6 (9.9) | 48.4–97.9 | 0.697 |
| SPARE-BA Slope (annual rate of change) | 1.3 (1.1) | −2.3–5.7 | 1.1 (0.9) | −2–4.6 | 0.052 |
| Number of brain MRI visits per participant | 3.4 (1.5) | 2–10 | 3.5 (1.4) | 2–11 | 0.787 |
| Follow-up, years | 4.7 (2.4) | 1–11 | 4.8 (2.3) | 1–10 | 0.512 |
| Other measures of interest | |||||
| Apolipoprotein E ε4 carrier status, n (%) | 44 (21) (n=207) | - | 67 (26) | - | 0.276 |
| Subsequent cognitive impairment/dementia | 36 (17%) | - | 24 (9%) | - | 0.017 |
| Total cholesterol, mg/dL | 171 (32) | 88–255 | 193 (35) | 102–373 | <0.001 |
| High-density lipoprotein, mg/dL | 55 (14) | 23 – 100 | 69 (16) | 34 – 128 | <0.001 |
| Low-density lipoprotein, mg/dL | 96 (29) | 23 – 182 | 106 (31) | 38 – 276 | <0.001 |
| Triglycerides, mg/dL | 100 (54) | 33 – 497 | 92 (40) | 34 – 357 | 0.075 |
| Medication use for high cholesterol, n (%) | 90 (42) | - | 101 (39) | - | 0.510 |
| Estradiol, ng/dL | 2.5 (0.8) (n=204) | 0.5–5.3 | 0.7 (0.6) (n=230) | 0.1 – 4.4 | <0.001 |
| Total testosterone, ng/dL | 489.1 (185.0) (n=204) | 11.0–1192.0 | 22.8 (13.6) (n=239) | 3.4–97.0 | <0.001 |
| Bioavailable testosterone, ng/dL | 112 (46) (n=203) | 8.8–310 | 3.7 (2.8) (n=224) | 0.7 – 18 | <0.001 |
| Sex hormone-binding glycoprotein, nmol/L | 58.4 (24.4) (n=203) | 14.0–139.4 | 74.9 (38.4) (n=241) | 13.3–334.7 | <0.001 |
| Lipid variables | |||||
| Acylcarnitines: Beta-oxidation rate | 0.13 (1.00) | −2.71 – 2.77 | −0.10 (0.99) | −3.48 – 2.99 | 0.013 |
| Acylcarnitines: Long-chain | 0.11 (0.98) | −3.76 – 2.11 | −0.09 (1.01) | −3.76 – 1.92 | 0.050 |
| Acylcarnitines: Medium-chain | 0.06 (0.88) | −2.79 – 2.30 | −0.05 (1.09) | −2.79 – 2.18 | 0.327 |
| Acylcarnitines: Short-chain | 0.12 (0.94) | −2.86 – 2.77 | −0.10 (1.04) | −4.03 – 3.01 | 0.023 |
| Ceramides: Very Long-chain | −0.26 (1.01) | −2.96 – 2.34 | 0.21 (0.94) | −2.44 – 2.96 | <0.001 |
| Ceramides: Long-chain | −0.31 (1.00) | −2.98 – 2.23 | 0.26 (0.93) | −2.72 – 2.66 | <0.001 |
| Glycoceremides: Very Long-chain | −0.23 (1.02) | −2.84 – 2.20 | 0.19 (0.94) | −2.40 – 2.88 | <0.001 |
| Glycoceremides: Long-chain | −0.28 (1.05) | −3.31 – 2.50 | 0.23 (0.89) | −2.21 – 3.17 | <0.001 |
| Glycerolipids & Cholesteryl Esters:Very Long-chain | −0.31 (1.01) | −3.24 – 2.27 | 0.25 (0.92) | −1.90 – 2.49 | <0.001 |
| Glycerolipids & Cholesteryl Esters:Long-chain | −0.27 (0.96) | −3.26 – 1.81 | 0.22 (0.98) | −3.18 – 2.79 | <0.001 |
| Sphingomyelins: Very Long-chain | −0.40 (0.99) | −3.24 – 2.35 | 0.33 (0.89) | −1.86 – 2.90 | <0.001 |
| Sphingomyelins: Long-chain | −0.51 (0.92) | −3.05 – 2.11 | 0.42 (0.86) | −2.51 – 3.70 | <0.001 |
| Triglycerides: Very Long-chain | −0.01 (1.07) | −4.15 – 2.86 | 0.01 (0.94) | −3.60 – 2.62 | 0.890 |
| Triglycerides: Long-chain | 0.01 (1.07) | −2.88 – 3.16 | −0.01 (0.95) | −2.84 – 2.82 | 0.763 |
Note: p-values were based on t-tests for continuous variables and chi-square tests for categorical variables. Sex differences in SPARE-BA index and lipid variables were adjusted for age. Lipid variables were based on log-transformed values and standardized to Z scores. The bold number indicates significance at a two-tailed p<0.05.