Parkinson’s Prevalence in Netherlands: Regional & Socioeconomic Differences Revealed

A large-scale study analyzing Parkinson’s disease across the Netherlands has revealed significant regional and demographic variations in the incidence of the condition. Researchers from Utrecht University and Radboudumc conducted a nationwide analysis between 2017 and 2022, marking the first time such comprehensive data has been mapped for the country. The findings suggest that environmental contributions may play a role in the disease’s distribution, alongside demographic factors.

The study, published in The Lancet Regional Health – Europe, utilized a new approach to identify new cases by linking multiple data sources. These included death certificates, medication prescriptions, health insurance claims, and hospital records. By connecting this health information to demographic and socioeconomic data, the team constructed a detailed picture of Parkinson’s disease risk across different neighborhoods and populations.

In this population study, we combined various health data, such as mortality figures, hospital data, insurance data and medication use. This allowed us to build a national registration for the first time and map out how many people in the Netherlands get the disease.

Roel Vermeulen, Epidemiologist, Utrecht University

Between 2017 and 2022, an average of 3,724 new Parkinson’s diagnoses were made annually. The analysis indicates that the number of new patients per year, when adjusted for population size, remains stable. However, the total number of people living with Parkinson’s disease in the Netherlands continues to increase. This rise is attributed to patients living longer with the condition rather than an surge in new infections or cases.

Researchers noted that increased survival rates can be partly ascribed to the success of ParkinsonNet, a nationwide network of healthcare professionals specialized in caring for people with Parkinson’s. The dynamic of stable incidence but rising prevalence was described using a specific analogy by the research team.

My colleague Bas Bloem always makes the comparison with a bathtub that is slowly filling up. The tap keeps flowing, while the drain does not run away faster. The number of patients stacks up, partly because people live longer and care is improving. Parkinson’s is therefore a growing health problem.

Roel Vermeulen, Epidemiologist, Utrecht University

Demographic and Socioeconomic Patterns

Beyond the overall numbers, the study uncovered clear demographic differences regarding who is most at risk. The data shows that the risk of developing Parkinson’s disease is higher among men than women. The risk increases with age, peaking between 75 and 85 years. These findings align with broader understandings of neurodegenerative conditions, yet the socioeconomic links presented a more complex picture.

One of the notable findings was that Parkinson’s disease is more common among individuals with a higher socioeconomic status. This pattern contradicts some general health trends where lower socioeconomic status is often associated with higher disease risk. The researchers acknowledged that while this pattern has been observed in earlier research, a definitive explanation remains elusive.

One possible explanation offered by the researchers involves smoking habits. Higher educated individuals tend to smoke less on average, while smoking has been linked to a lower risk of Parkinson’s in some studies. The team theorized that dopamine, a signaling substance in the brain important for behavior and movement, might play a role in this correlation.

Researchers suggest that people with naturally higher dopamine levels may have a higher tendency toward risk behavior, such as smoking, but simultaneously have a lower chance of developing Parkinson’s. Conversely, individuals with lower dopamine levels might be less likely to smoke but more susceptible to the disease. This hypothesis highlights the complex biological and behavioral interactions involved in the condition’s etiology.

Regional Variations and Environmental Factors

The study also highlighted significant geographic differences in disease distribution. Parkinson’s disease was found to be more common in the northern provinces of the Netherlands and less common in the southern provinces. This spatial variation suggests that location-specific factors may influence risk.

What stood out especially was the regional pattern. We looked at environmental factors such as air pollution, pesticides and urbanization, but still these factors alone could not explain the regional differences well.

Roel Vermeulen, Epidemiologist, Utrecht University

While the study examined environmental factors like air pollution and pesticides, the researchers found no clear overlap between these specific factors and the regional pattern on their own. This does not rule out their influence but indicates that the impact is difficult to visualize with current data. The complexity of the disease likely involves multiple factors working together to determine risk.

Another limitation noted was that the study primarily looked at the place of residence at the time of diagnosis. To truly understand causes, the researchers argue that an individual’s entire residential and living history must be considered. Genetic research indicates that genetics explain only a small part of Parkinson’s, and genetic differences between people in different regions are likely limited. This points toward environmental factors playing a role in the regional variation of the disease.

Future Research and Healthcare Planning

Understanding temporal trends, demographic drivers, and regional variations in Parkinson’s disease risk is critical for guiding healthcare planning. The nationwide registration established by this study allows researchers to follow whether the number of people with Parkinson’s increases or decreases over time. It also facilitates further investigation into which factors influence risk on an individual level.

Future research will focus specifically on the influences of air quality and exposure to pesticides. These are environmental factors that may play an important role but are not yet well understood. By utilizing the new national registration, the team aims to investigate why some people develop Parkinson’s and others do not.

The findings underscore the importance of continued monitoring and specialized care networks. As the total number of patients increases due to longevity, healthcare systems must adapt to manage the growing prevalence even if the incidence rate remains stable. The collaboration between Utrecht University and Radboudumc provides a foundation for identifying potential environmental and socioeconomic risk factors that could inform future public health strategies.