Table 1.
Descriptive statistics of the study population and the NMSS.
| Baseline | Two-year follow-up | Z | p | r | |
|---|---|---|---|---|---|
| N | 499 | 499 | |||
| Sex | |||||
| Male | 294 (58.9) | 294 (58.9) | / | / | / |
| Female | 205 (41.1) | 205 (41.1) | / | / | / |
| Age (years) | 64 (57–69) | 66 (59–71) | / | / | / |
| Disease duration | 5 (2–8) | 7 (4–10) | / | / | / |
| HY off | 2 (2–2) | 2 (2–2) | −5.973 | < 0.001* | 0.286 |
| UPDRS III off | 20 (13.5–29) | 24 (16–32) | −6.644 | < 0.001* | 0.318 |
| UPDRS IV off | 1 (0–3) | 2 (0–4) | −5.956 | < 0.001* | 0.272 |
| MMSE | 30 (29–30) | 29 (28–30) | −7.448 | < 0.001* | 0.339 |
| BDI–II | 7 (3–12) | 7 (3–13) | −0.845 | 0.398 | 0.038 |
| NMSS, total score | 34 (19–59) | 43 (22–71) | −6.040 | < 0.001* | 0.270 |
| Cardiovascular (domain 1) | 0 (0–1) | 0 (0–2) | −3.397 | 0.001* | 0.152 |
| 1. Light headedness | 0 (0–1) | 0 (0–2) | −3.457 | < 0.001* | 0.155 |
| 2. Fainting | 0 (0–0) | 0 (0–0) | −1.165 | 0.244 | 0.052 |
| Sleep/fatique (domain 2) | 6 (2–12) | 7 (3–14) | −3.632 | < 0.001* | 0.163 |
| 3. Daytime sleepiness | 1 (0–3) | 1 (0–4) | −2.936 | 0.003* | 0.131 |
| 4. Fatigue | 1 (0–4) | 2 (0–6) | −5.059 | < 0.001* | 0.226 |
| 5. Sleep initiation | 0 (0–2) | 0 (0–3) | −1.843 | 0.065 | 0.083 |
| 6. Restless legs | 0 (0–2) | 0 (0–2) | −0.030 | 0.976 | 0.001 |
| Mood/cognition (domain 3) | 3 (0–11) | 4 (0–14) | −3.139 | 0.002* | 0.141 |
| 7. Loss of interest | 0 (0–1) | 0 (0–1) | −2.958 | 0.003* | 0.132 |
| 8. Lack of motivation | 0 (0–1) | 0 (0–2) | −2.837 | 0.005* | 0.127 |
| 9. Feeling nervous | 0 (0–2) | 0 (0–3) | −1.089 | 0.276 | 0.049 |
| 10. Feeling sad | 0 (0–2) | 1 (0–3) | −2.473 | 0.013* | 0.111 |
| 11. Flat mood | 0 (0–1) | 0 (0–2) | −2.165 | 0.030* | 0.097 |
| 12. Anhedonia | 0 (0–2) | 0 (0–2) | −1.493 | 0.135 | 0.067 |
| Perceptual problems (domain 4) | 0 (0–0) | 0 (0–1) | −5.190 | < 0.001* | 0.232 |
| 13. Hallucinations | 0 (0–0) | 0 (0–0) | −3.866 | < 0.001* | 0.173 |
| 14. Delusions | 0 (0–0) | 0 (0–0) | −3.773 | < 0.001* | 0.169 |
| 15. Diplopia | 0 (0–0) | 0 (0–0) | −3.120 | 0.002* | 0.140 |
| Attention/memory (domain 5) | 2 (0–4) | 2 (0–7) | −4.128 | < 0.001* | 0.185 |
| 16. Concentration | 0 (0–2) | 0 (0–3) | −2.595 | 0.009* | 0.116 |
| 17. Forgetfulness | 0 (0–2) | 0 (0–2) | −3.548 | < 0.001* | 0.159 |
| 18. Forget to do things | 0 (0–1) | 0 (0–1) | −3.004 | 0.003* | 0.134 |
| Gastrointestinal tract (domain 6) | 1 (0–5) | 2 (1–7) | −5.163 | < 0.001* | 0.231 |
| 19. Sialorrhea | 0 (0–1) | 0 (0–2) | −3.294 | 0.001* | 0.147 |
| 20. Dysphagia | 0 (0–0) | 0 (0–1) | −2.707 | 0.007* | 0.121 |
| 21. Constipation | 0 (0–2) | 0 (0–4) | −4.127 | < 0.001* | 0.185 |
| Urinary (domain 7) | 6 (1–12) | 6 (2–13) | −3.419 | 0.001* | 0.153 |
| 22. Urgency | 1 (0–4) | 2 (0–6) | −2.827 | 0.005* | 0.127 |
| 23. Frequency | 1 (0–4) | 1 (0–4) | −1.378 | 0.168 | 0.062 |
| 24. Nocturia | 1 (0–4) | 2 (0–4) | −2.808 | 0.005* | 0.126 |
| Sexual function (domain 8) | 1 (0–8) | 4 (0–8) | −3.000 | 0.003* | 0.134 |
| 25. Interest | 0 (0–4) | 0 (0–4) | −2.262 | 0.024* | 0.101 |
| 26. Problems having sex | 0 (0–4) | 0 (0–4) | −3.021 | 0.003* | 0.135 |
| Miscellaneous (domain 9) | 5 (1–12) | 6 (1–12) | −2.921 | 0.003* | 0.131 |
| 27. Pain | 0 (0–1) | 0 (0–2) | −2.701 | 0.007* | 0.121 |
| 28. Taste/smell | 2 (0–6) | 2 (0–6) | −1.103 | 0.270 | 0.049 |
| 29. Weight change | 0 (0–0) | 0 (0–0) | −0.899 | 0.369 | 0.040 |
| 30. Hyperhidrosis | 0 (0–1) | 0 (0–2) | −2.312 | 0.021* | 0.103 |
The number of participants is given in absolute values; other values are given as the medians and interquartile ranges; categorical parameters are given as absolute values and percentages. For group comparisons, the paired Wilcoxon signed-rank test was used to examine the differences over time. BDI-II, revised version of the Beck Depression Inventory; HY, Hoehn and Yahr stage; MMSE, Mini-Mental State Examination; N, number of participants; NMSS, Non-Motor Symptoms Scale in Parkinson's Disease; p*, significant group differences; r, effect sizes of the group differences given by the Pearson correlation coefficient; UPDRS, Unified Parkinson's Disease Rating Scale. Z, Z-score of the paired Wilcoxon signed-rank test.