Parkinson’s disease (PD) is a complex neurodegenerative disorder with no cure in sight. Clinical challenges of the disease include the inability to make a definitive diagnosis at the early stages and difficulties in predicting the disease progression. The unmet demand to identify reliable biomarkers for early diagnosis and management of the disease course of PD has attracted a lot of attention. However, only a few reported candidate biomarkers have been tried in clinical practice at the present time. Studies on PD biomarkers have often overemphasized the discovery of novel identity, whereas efforts to further evaluate such candidates are rare. Therefore, we update the new development of biomarker discovery in PD and discuss the standard process in the evaluation and assessment of the diagnostic or prognostic value of the identified potential PD biomarkers in this review article. Recent developments in combined biomarkers and the current status of clinical trials of biomarkers as outcome measures are also discussed. We believe that the combination of different biomarkers might enhance the specificity and sensitivity over a single measure that might not be sufficient for such a multiplex disease.

中文翻译：

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帕金森氏病的生物标记物：它们的功效如何？

帕金森氏病（PD）是一种复杂的神经退行性疾病，无法治愈。该疾病的临床挑战包括无法在早期做出明确的诊断以及难以预测疾病的进展。为PD的病程进行早期诊断和管理而鉴定可靠的生物标志物的需求未得到满足，引起了很多关注。然而，目前在临床实践中仅尝试了少数报道的候选生物标志物。有关PD生物标志物的研究通常过分强调了新颖身份的发现，而进一步评估此类候选物的努力却很少。因此，我们将在本文中更新PD中生物标志物发现的新发展，并在评估和评估已鉴定的潜在PD生物标志物的诊断或预后价值中讨论标准过程。还讨论了联合生物标志物的最新发展以及作为结果指标的生物标志物临床试验的现状。我们相信，不同的生物标志物的组合可能会通过单一措施增强特异性和敏感性，而单一措施可能不足以应对此类多重疾病。