EMBARGOED FOR RELEASE UNTIL 4 PM ET, August 07, 2024
In Parkinson鈥檚, Dementia May Occur Less Often, or Later, than Thought
MINNEAPOLIS 鈥 There鈥檚 some good news for people with Parkinson鈥檚 disease: The risk of developing dementia may be lower than previously thought, or dementia may occur later in the course of the disease than previously reported, according to a study published in the August 7, 2024, online issue of , the medical journal of the 好色先生. 鈥淭he development of dementia is feared by people with Parkinson鈥檚, and the combination of both a movement disorder and a cognitive disorder can be devastating to them and their loved ones,鈥 said study author Daniel Weintraub, MD, of the University of Pennsylvania in Philadelphia. 鈥淭hese results provide more hopeful estimates of the long-term risk of dementia for people with Parkinson鈥檚 disease, suggesting that there is a longer window to intervene to prevent or delay cognitive decline.鈥 Previous studies had indicated that about 80% of people with Parkinson鈥檚 disease would develop dementia within 15-20 years after being diagnosed with Parkinson鈥檚. 鈥淲hile these studies were important in highlighting the issue of cognitive decline in Parkinson鈥檚 disease, the studies were conducted many years ago, were relatively small and had other limitations, so we wanted to re-evaluate these findings,鈥 Weintraub said. For the study, researchers analyzed data from two large, prospective studies. An international study involved 417 participants with an average age of 62 who were newly diagnosed with Parkinson鈥檚 disease and had not yet received treatment for the disease at study enrollment. A study at the University of Pennsylvania involved 389 people with Parkinson鈥檚 with an average age of 69 who had been diagnosed with Parkinson鈥檚 an average of six years before the start of the study. The participants were followed to see whether they developed dementia. The international study showed an estimated probability of being diagnosed with dementia 10 years after being diagnosed with Parkinson鈥檚 disease of 9%. For the Pennsylvania study, the probability of being diagnosed with dementia 10 years after the Parkinson鈥檚 diagnosis was 27%. For the latter study, researchers found an estimated risk of dementia at 50%, 15 years after a Parkinson鈥檚 diagnosis and 74%, 20 years after diagnosis. Factors that increased the risk of dementia in the Pennsylvania study included being older when Parkinson鈥檚 was diagnosed, being male and having a lower level of education. A limitation of both studies is that participants were highly educated, mainly white people and were recruited for participation in a research study, so they may not represent the general population. The international study, the Parkinson鈥檚 Progression Markers Initiative, is a public-private partnership funded by the Michael J. Fox Foundation for Parkinson鈥檚 Research and numerous funding partners. The University of Pennsylvania study was supported by the National Institute on Aging. Learn more about Parkinson's disease at , home of the 好色先生鈥檚 free patient and caregiver magazine focused on the intersection of neurologic disease and brain health. Follow Brain & Life庐 on , and . When posting to social media channels about this research, we encourage you to use the hashtags #Neurology and #AANscience.