<p>Parkinson’s disease (PD) presents with diverse symptoms, partly influenced by motor symptom asymmetry, which reflects hemispheric brain specialization. This systematic review of 80 studies explored how lateralized motor symptoms affect non-motor outcomes in PD, including cognition, emotion, and psychiatric health. Patients with right-sided motor symptoms (left-hemisphere pathology) show more global cognitive decline and higher dementia risk, while those with left-sided symptoms (right-hemisphere pathology) more often experience psychiatric issues like depression, anxiety, and impaired emotional recognition. Visuospatial deficits were consistently linked to left-sided symptoms, aligning with right-hemisphere dysfunction. Although findings vary across studies, this pattern suggests the relevance of brain lateralization in non-motor symptom assessment. Motor asymmetry may also affect treatment responses, such as deep brain stimulation outcomes. However, inconsistencies in study methods—definitions of asymmetry, motor subtypes, and comorbidities—limit meta-analytic conclusions. Overall, incorporating motor symptom asymmetry into PD diagnosis and treatment could enhance personalized care, warranting more standardized future research.</p>