Parkinson's disease (PD) is a progressive neurodegenerative disorder, representing nowadays a neurological condition with the fastest-growing rate and the primary cause of disability worldwide. Parkinson's disease doubled in number to almost 6 million patients between 1990 and 2015.1 According to recent data, this population is expected to double again to nearly 12 million by 2040, primarily due to aging.1 Other sources propose a similar growth trajectory, with estimates indicating that by 2030, the global prevalence of PD will increase substantially.2 Parkinson's disease is primarily characterized by motor symptoms such as resting tremor, rigidity, akinesia, or bradykinesia, creating the hallmark of diagnostic symptoms. Additionally, other motor dysfunctions, such as discoordination, impaired handwriting, and speech deficits, can occur over time. However, non-motor or prodromal symptoms, including hyposmia, sleep disorders, gastrointestinal dysfunction, anxiety, and depressive episodes, may precede the motor symptoms of PD by up to 20 years.3 Therefore, prodromal symptoms have gained attention as potential early indicators of disease progression. One of the most prominent and early-developed signs is considered to be hyposmia (reduced sense of smell), which has been shown to have significant diagnostic importance in PD,4,5 based on the predetermined path of neuropathological distribution of Lewy bodies and neurites, which can be seen earliest in olfactory nerves and nuclei of the glossopharyngeal and vagal nerves, causing the majority of non-motor symptoms. On the other hand, cognitive impairment and/or dementia impact the quality of life and disease management as the later-stage complications of PD. This study explores the relationship between the early and late PD symptoms of hyposmia and cognitive status in patients with Parkinson's disease.