TABLE 1.
CSF levels for monoamine metabolites in the PPMI cohort
| HC (n = 56) | PD (n = 95) | Difference PD‐HC | ||||||||
|---|---|---|---|---|---|---|---|---|---|---|
| Variable | Mean ± SD | <LOD | ICC | Mean ± SD | <LOD | Estimate | P Value | AUC | Specificity | Sensitivity |
| 3‐Methoxytyrosine | 1.33 ± 0.28 | 0.00 | 0.58 | 2.79 ± 2.11 | 0.00 | −0.02 | 0.64 | 0.54 | 0.00 | 1.00 |
| DOPAC | −1.10 ± 0.41 | 0.00 | 0.74 | −0.99 ± 0.77 | 0.00 | −0.20 | 0.011 | 0.63 | 0.23 | 0.89 |
| DOPA | −0.31 ± 0.25 | 0.00 | 0.63 | 0.59 ± 1.42 | 0.00 | −0.01 | 0.85 | 0.53 | 0.00 | 1.00 |
| DOPEG | 0.49 ± 0.32 | 0.00 | 0.70 | 0.50 ± 0.37 | 0.00 | 0.04 | 0.50 | 0.53 | 0.00 | 1.00 |
| HMPG | 2.07 ± 0.23 | 0.00 | 0.47 | 2.00 ± 0.25 | 0.00 | −0.04 | 0.51 | 0.57 | 0.00 | 1.00 |
| 4‐Hydroxy‐3‐methoxymandelic acid | −0.14 ± 0.34 | 0.00 | 0.69 | −0.13 ± 0.33 | 1.31 | −0.02 | 0.84 | 0.54 | 0.00 | 1.00 |
| 5‐HIAA | 3.71 ± 0.45 | 0.00 | 0.74 | 3.53 ± 0.45 | 0.00 | −0.12 | 0.076 | 0.59 | 0.07 | 0.99 |
| Dopamine | −4.58 ± 0.41 | 2.38 | 0.61 | −4.19 ± 0.61 | 2.62 | 0.15 | 0.072 | 0.61 | 0.13 | 0.96 |
| Histamine | −2.56 ± 0.44 | 18.45 | 0.19 | −2.32 ± 0.95 | 24.02 | 0.25 | 0.077 | 0.58 | 0.02 | 0.93 |
| HVA | 3.85 ± 0.42 | 0.00 | 0.71 | 3.74 ± 0.60 | 0.00 | −0.33 | <0.0001 | 0.71 | 0.43 | 0.87 |
| Noradrenaline (norepinephrine) | −1.52 ± 0.46 | 0.00 | 0.69 | −1.47 ± 0.44 | 0.00 | 0.08 | 0.48 | 0.56 | 0.00 | 1.00 |
| Normetanephrine | −2.28 ± 0.43 | 0.00 | 0.71 | −2.27 ± 0.43 | 0.00 | 0.02 | 0.76 | 0.47 | 1.00 | 0.00 |
| (DOPEG + NM + HMPG + NA)/dopamine | 7.22 ± 0.39 | 0.02 | n/a | 6.78 ± 0.56 | 0.03 | −0.17 | 0.013 | 0.64 | 0.24 | 0.93 |
| DOPAC/dopamine | 3.49 ± 0.43 | 0.02 | n/a | 3.22 ± 0.55 | 0.03 | −0.35 | <0.0001 | 0.71 | 0.38 | 0.84 |
| Dopamine/DOPA | −4.28 ± 0.41 | 0.02 | n/a | −4.82 ± 1.10 | 0.03 | 0.16 | 0.086 | 0.62 | 0.07 | 0.96 |
| DOPEG/noradrenaline | 2.01 ± 0.42 | 0.00 | n/a | 1.97 ± 0.38 | 0.00 | −0.05 | 0.45 | 0.55 | 0.00 | 1.00 |
| HMPG/noradrenaline | 3.59 ± 0.40 | 0.00 | n/a | 3.47 ± 0.38 | 0.00 | −0.13 | 0.082 | 0.61 | 0.07 | 0.95 |
| HVA/dopamine | 8.44 ± 0.45 | 0.02 | n/a | 7.95 ± 0.50 | 0.03 | −0.48 | <0.0001 | 0.77 | 0.47 | 0.85 |
| Noradrenaline/DOPA | −1.21 ± 0.43 | 0.00 | n/a | −2.06 ± 1.46 | 0.00 | 0.09 | 0.17 | 0.58 | 0.02 | 0.99 |
| Normetanephrine/noradrenaline | −0.76 ± 0.23 | 0.00 | n/a | −0.79 ± 0.28 | 0.00 | −0.07 | 0.31 | 0.55 | 0.00 | 1.00 |
Monoamine metabolite levels in PPMI HC and PD CSF samples: levels (log2 transformed), percentages <LOD, ICCs to assess stability between baseline, 1‐year follow‐up, and 2‐year follow‐up in the PPMI HC group, HC‐PD group differences with corresponding AUC and receiver operating characteristics curves, and specificity and sensitivity. Boldface reflects significant case–control differences after multiple testing correction.
CSF, cerebrospinal fluid; PPMI, Parkinson's Progressive Markers Initiative; HC, healthy control; PD, Parkinson's disease; SD, standard deviation; LOD, below the limit of detection; ICC, intraclass correlation coefficient; AUC, area under the curve; DOPAC, 3,4‐dihydroxyphenylacetic acid; DOPA, 3,4‐dihydroxyphenylalanine; DOPEG; 3,4‐dihydroxyphenylglycol; HMPG, 4‐hydroxy‐3‐methoxyphenylglycol; 5‐HIAA, 5‐hydroxy‐3‐indoleacetic acid; HVA, homovanillic acid; n/a, not applicable.