Diagnostic Delays in Parkinson’s Disease in Thailand: Clinical Pitfalls and Health System Barriers

Background: Parkinson’s disease (PD) is a progressive neurodegenerative disorder in which early diagnosis can improve quality of life and reduce disability. However, diagnostic delays remain common, particularly in low- and middle-income countries. This study examined clinical and system-level factors contributing to diagnostic delay in Thailand. Methods: A retrospective chart review was conducted on patients newly diagnosed with PD at Thammasat University Hospital between June 2020 and June 2024. Demographic, clinical, and healthcare access data were analyzed. Diagnostic intervals were measured as onset-to-visit (OTV) and visit-to-diagnosis (VTD). Results: Of 1,093 screened patients, 109 newly diagnosed PD cases met inclusion criteria. The median OTV was 360 days, while the VTD was 10 days. Tremor was the most common initial symptom (75%). Patients with higher education and extended family support sought care earlier, while those under the Universal Coverage Scheme (UCS) experienced longer delays (median 541 vs. 181 days in privately insured). Over half were initially misdiagnosed, especially by non-neurologists. Conclusion: Diagnostic delay in Thai PD patients stems mainly from late help-seeking and inequities in healthcare access. Addressing these gaps requires public awareness, physician training, streamlined UCS referral pathways, and adoption of biomarker-supported digital tools to ensure earlier and more equitable diagnosis.