Table 2. Association analysis of plasma trace elements with PD1.
| Element | Category | Nagelkerke R square | First quartile | Second quartile | Third quartile | Fourth quartile | p value for trend 2 |
|---|---|---|---|---|---|---|---|
| Se | Concentration | - | <83 | 83-106 | 107-130.75 | >130.75 | - |
| n (control/PD) | - | 80/53 | 89/53 | 73/57 | 60/75 | - | |
| Model 1 | 0.031 | 0.505 (0.308,0.827) | 0.461 (0.284,0.749) | 0.598 (0.366,0.977) | 1 | 0.153 | |
| Model 2 | 0.396 | 0.218 (0.114,0.415) | 0.252 (0.137,0.462) | 0.431 (0.234,0.793) | 1 | 0.055 | |
| Cu | Concentration | - | <862 | 862-1038 | 1039-1191.5 | >1191.5 | - |
| n (control/PD) | - | 62/72 | 67/69 | 88/47 | 85/50 | - | |
| Model 1 | 0.041 | 2.065 (1.259,3.386) | 1.782 (1.093,2.905) | 0.922 (0.560,1.518) | 1 | 0.153 | |
| Model 2 | 0.396 | 1.560 (0.842,2.892) | 1.336 (0.737,2.421) | 0.830 (0.454,1.516) | 1 | 0.250 | |
| Fe | Concentration | - | <1063 | 1063-1413 | 1414-1888 | >1888 | - |
| n (control/PD) | - | 80/53 | 88/52 | 73/61 | 61/72 | - | |
| Model 1 | 0.029 | 0.529 (0.323,0.868) | 0.471 (0.288,0.769) | 0.681 (0.419,1.107) | 1 | 0.150 | |
| Model 2 | 0.396 | 0.348 (0.189,0.641) | 0.386 (0.214,0.698) | 0.509 (0.286,0.907) | 1 | 0.040 | |
| Zn | Concentration | - | <825 | 825-1100 | 1101-1375 | >1375 | - |
| n (control/PD) | - | 21/103 | 84/77 | 90/37 | 107/21 | - | |
| Model 1 | 0.302 | 24.875 (12.806,48.320) | 4.685 (2.673,8.211) | 2.093 (1.143,3.834) | 1 | 0.128 | |
| Model 2 | 0.396 | 40.728 (19.327,85.828) | 7.067 (3.766,13.264) | 2.698 (1.401,5.195) | 1 | 0.040 |
1 Odds ratios (95% CI) from logistic models were represented for dichoutomous outcomes (presence of PD) with the highest quartile as the reference group. Model 1 was for individual trace element adjusted with age and sex; Model 2 was for all four elements as ordinal variables adjusted with age and sex.
2 Trend analyses across quartiles were performed using the ordinal variables containing median element concentrations for each quartile.