| الوصف: |
Parkinson's disease (PD) is typically diagnosed between 55 and 65 years of age, with increasing prevalence (> 1%-2%) above 60 years. The prodromal phase of PD begins at 12-14 years before the disease is diagnosed, when it presents with neurodegenerative symptoms or indicators. However, clinical diagnosis is possible only after fully evolved PD despite an increasing number of emerging imaging and biochemical biomarkers. This review summarizes apparent physical signs and biochemical and radiological biomarkers indicating prodromal PD. A literature search was conducted in PubMed, CINAHL, Cochrane Library, and Google Scholar. Sixty-five studies, including meta-analyses, systematic reviews, literature reviews, randomized controlled trials, nonrandomized trials, and prospective/cohort studies published between 2012 and 2022 were reviewed. Findings reported depression, constipation, fatigue, urinary dysfunction, olfactory disturbance, nonintentional tremors, and rapid eye movement sleep behavior disorder as potential biomarkers of prodromal Parkinson's disease. However, the existence of these physical symptoms in isolation cannot be diagnostic. The most extensively researched biochemical marker for the early diagnosis of PD is α-synuclein. Other biochemical markers for PD include protein deglycase genes, β-glucocerebrosidase activity, CSF o/t-syn, and Aβ42/tau ratios. Radiologically, DAT imaging, vesicular monoamine transporter 2 imaging, 18F-fluorodeoxyglucose levels, and PET and SPECT radiotracers are used for prediagnosis. Further research is necessary to explore a multimodal approach using technology advancements for early detection, disease monitoring, and rehabilitation. |