Table 1.
ALS Participant Demographics Prior to Multiple Imputation
| Covariate | ALS Cases (N = 167) | HR | 95% CI | P-Value |
|---|---|---|---|---|
| Age at plasma collection (years)* | 61.6 (53.3–68.8) | 1.02 | (1.01, 1.04) | 0.007 |
| BMI at study entry (kg/m2)** | 25.7 (22.3–28.4) | 1.02 | (0.97, 1.07) | 0.507 |
| BMI slope** | −0.2 (−0.6–0.1) | 0.91 | (0.65, 1.28) | 0.598 |
| Education1 | 0.80 | (0.55, 1.17) | 0.245 | |
| HS/GED or less | 54 (32.3) | |||
| Some College / Associate’s | 44 (26.3) | |||
| Bachelor’s | 42 (25.1) | |||
| Master’s / Professional | 26 (15.6) | |||
| Missing | 1 (0.6) | |||
| Family history of ALS | ||||
| No | 142 (85.0) | Ref | Ref | Ref |
| Yes | 18 (10.8) | 1.26 | (0.73, 2.18) | 0.402 |
| Missing | 7 (4.2) | |||
| Military service | ||||
| No | 133 (79.6) | Ref | Ref | Ref |
| Yes | 26 (15.6) | 0.72 | (0.42, 1.25) | 0.242 |
| Missing | 8 (4.8) | |||
| Sex | ||||
| Female | 68 (40.7) | 1.40 | (0.97, 2.02) | 0.071 |
| Male | 99 (59.3) | Ref | Ref | Ref |
| Smoking | ||||
| Non-smoker | 92 (55.1) | Ref | Ref | Ref |
| Former smoker | 52 (31.1) | 0.84 | (0.56, 1.26) | 0.407 |
| Current smoker | 18 (10.8) | 0.80 | (0.42, 1.51) | 0.487 |
| Missing | 5 (3.0) | |||
| Age at diagnosis (years) | 60.9 (52.7–68.2) | 1.03 | (1.01, 1.04) | 0.001 |
| El Escorial criteria | ||||
| Possible | 27 (16.2) | Ref | Ref | Ref |
| Probable, LS | 43 (25.7) | 1.86 | (0.94, 3.68) | 0.074 |
| Probable | 51 (30.5) | 1.65 | (0.84, 3.27) | 0.148 |
| Definite | 45 (26.9) | 2.36 | (1.20, 4.61) | 0.012 |
| Missing | 1 (0.6) | |||
| NIV user | ||||
| No | 65 (38.9) | Ref | Ref | Ref |
| Yes | 98 (58.7) | 0.89 | (0.61, 1.30) | 0.548 |
| Missing | 4 (2.4) | |||
| Onset segment | ||||
| Bulbar | 48 (28.7) | 2.31 | (1.47, 3.61) | <0.001 |
| Cervical | 56 (33.5) | Ref | Ref | Ref |
| Lumbar | 63 (37.7) | 1.07 | (0.69, 1.66) | 0.760 |
| Time between diagnosis and blood draw (years)***2 | 0.57 (0.36–0.83) | 0.39 | (0.30, 0.49) | <0.001 |
| Time between symptom onset and diagnosis (years)2 | 1.01 (0.67–1.67) | 0.76 | (0.60, 0.96) | 0.022 |
Table of descriptive statistics for the overall ALS participant study population. For continuous variables, Median (25th – 75th percentile), and for categorical variables, N (%). Hazard ratios, 95% confidence intervals, and p-values correspond to univariable unadjusted Cox proportional hazards models.
Abbreviations: ALS, amyotrophic lateral sclerosis; BMI, body mass index; CI, confidence interval; GED, Graduate Equivalency Diploma; HR, hazard ratio; HS, high school; kg, kilograms; LS, lab supported; m, meters; NIV, non-invasive ventilation; Ref, reference category.
Median, 25th percentile, and 75th percentile are computed using 165 cases (2 cases are missing).
Median, 25th percentile, and 75th percentile are computed using 111 cases (56 cases are missing).
Median, 25th percentile, and 75th percentile are computed using 164 cases (3 cases are missing).
Hazard ratio corresponds to those with at least some post-high school education compared to those with no post-high school education.
Hazard ratios correspond to log-transformed time between diagnosis and blood draw and log-transformed time between symptom onset and diagnosis.