Biological sex differences go beyond internal and external anatomical differences. These differences can greatly impact the etiology and pathophysiology of many diseases and, consequently, can influence incidence, diagnostic accuracy, and clinical outcomes. 

Among neurological conditions that may be influenced by biological sex is Parkinson’s disease. While the risk of developing Parkinson’s disease is 1.5 as high in men than in women, research shows that women have a higher mortality rate and faster progression of the disease. In the U.S. alone, there are more than 400,000 women living with Parkinson’s disease—yet, women with Parkinson’s disease remain severely underrepresented in Parkinson’s research.

There is still a clear and urgent need for more research in this space, however, we are starting to see some research bringing these differences to light. In this article, we will take a look at emerging research surrounding Parkinson’s in women versus men and the role of research in delivering personalized treatment and care.

Parkinson’s in Women Versus Men

Current evidence points to biological sex as an important factor involved in the development and expression of Parkinson’s disease. It is possible that Parkinson’s disease development involves distinct pathological mechanisms in male and female patients. Alternatively, it may involve the same mechanism but act differently between biological sexes. Regardless, emerging research shows that there may be a physiological difference in how Parkinson’s disease pathology manifests in women versus men. While research is still highly limited, studies suggest the following differences.

Prevalence, Onset & Progression:

• Men are more likely than women to develop Parkinson’s disease. Some believe estrogen has a neuroprotective effect in women. Some believe men are more likely to experience head trauma and be exposed to toxins which are both established risk factors for Parkinson’s disease development. Others suggest an X linkage of genetic risk factors.
• Age of Parkinson’s disease onset may be later in women compared to men.
• Compared to men, women have a higher mortality rate and experience a faster rate of progression.

Motor and Non-Motor Symptoms:

• Women may experience different motor and non-motor symptoms at different severities. Motor symptoms have been found to emerge later in women with different characteristics, such as reduced rigidity, a higher tendency to develop postural instability, and tremor as a more common initial symptom. Research shows that non-motor symptoms—such as depression, fatigue, restless legs, pain, constipation, loss of taste or smell, excessive sweating, and weight change—are more common and more severe in women.
• Women report worsening symptoms during perimenopause. Some researchers hypothesize this to be related to the decreased levels of estrogen.
• Women are at an elevated risk for levodopa-related motor complications. Minor changes in medications or the timing of medications can increase the negative side effects, such as dyskinesia, in women.
• Research suggests that men with Parkinson’s disease have worse general cognitive abilities. One study found that women with Parkinson’s disease perform better at the Symbol Digit Modalities Test, verbal fluency tests, and overall cognitive function, as measured by the Montreal Cognitive Assessment (MoCA). However, it has also been found that women have worse visuospatial abilities.

Psychosocial Aspects:

• Women with Parkinson’s disease have less social support and report worse psychological stress.
• Women with Parkinson’s disease are more likely to live alone and attend medical appointments alone.
• Women with Parkinson’s disease are at greater risk of receiving lower-quality care.

Identifying and understanding the differences in Parkinson’s in women versus men will likely play a crucial role in terms of diagnostic accuracy and therapeutic approaches. Continued research and increased awareness around these differences may help bridge the gap in patient care by better capturing the needs of women with Parkinson’s disease.

The Path Towards Precision Care

Ultimately, clinical research drives patient care. To be able to provide precise, personalized treatment and care, we need to understand the role of aspects such as biological sex, genetics, and cultural context in Parkinson’s disease. With a greater understanding of how hormones and biological sex influence Parkinson’s disease, healthcare providers can customize management plans to adjust for unique stages of women’s lives, including during menstruation, pregnancy, perimenopause, menopause, and postmenopause. 

More research surrounding the differences between men and women with Parkinson’s disease is fundamental to the ability to provide women with equal care and treatment. There is still much to be learned about the effect of biological sex on Parkinson’s disease development, progression, and response to treatments and therapies.

Diagnosing Lewy body dementia is notoriously challenging. For people living with Lewy body dementia, this often means a lengthy journey to diagnosis, seeing several doctors and undergoing many tests before reaching a correct diagnosis.

Despite being the second most common cause of dementia, Lewy body dementia is the most misdiagnosed dementia, according to the Lewy Body Dementia Association (LBDA). In a 2010 survey, the LBDA found that nearly 80% of people with Lewy body dementia received a diagnosis for a different cognitive, movement, or psychiatric disorder before ultimately learning they had Lewy body dementia.

In this article, we will discuss the challenges of diagnosing Lewy body dementia and the path toward early and accurate diagnosis.

Why Is Diagnosing Lewy Body Dementia So Challenging?

Similar to many other causes of dementia, there is no single test that can definitively diagnose Lewy body dementia. Instead, it is diagnosed “clinically,” meaning the diagnosis is dependent on medical history, answers to certain questions, a physical examination, and the presence of specific physical symptoms. Doctors may also utilize blood tests and brain imaging to rule out other causes of dementia and other movement disorders.

Like Alzheimer’s disease and Parkinson’s disease, people with Lewy body dementia often experience a range of cognitive, functional (movement), and behavioral changes throughout the disease continuum—and many of their symptoms overlap at various stages of the disease. 

In the early stages of Lewy body dementia, symptoms may appear very similar to those of Alzheimer’s disease. For example, early symptoms of Lewy body dementia are changes in thinking and reasoning, judgment and memory impairment, issues with sleep, visual hallucinations, and changes in mood—all of which can also be symptoms of Alzheimer’s disease.

As the disease progresses, people living with Lewy body dementia usually also experience functional impairments, such as bradykinesia (slowness of movement), resting tremor, or rigidity—all of which are core motor symptoms of Parkinson’s disease. 

Differentiating Between Lewy Body Dementia, Alzheimer’s, and Parkinson’s

While Lewy body dementia, Alzheimer’s disease, and Parkinson’s may present with similar symptoms, there are some subtle differences that can aid in providing a correct diagnosis:

• Memory impairment and other cognitive changes can occur in all three diseases. In Lewy body dementia and Alzheimer’s disease, memory impairment can occur early in the disease continuum. However, it’s typically more noticeable in Alzheimer’s disease compared to Lewy body dementia. 
  
  Lewy body dementia is also associated with fluctuating cognition, meaning cognitive impairment isn’t always present. Cognitive impairment can occur in Parkinson’s disease as well but typically occurs much later in the disease.

• Hallucinations can occur in both Alzheimer’s and Lewy body dementia, but they tend to occur in earlier stages of Lewy body dementia and later stages of Alzheimer’s disease.

• Movement symptoms, such as bradykinesia, resting tremor, and rigidity can occur in both Parkinson’s disease and Lewy body dementia. However, people with Lewy body dementia typically experience dementia before, at the same time as, or within a year of the onset of movement symptoms. People living with Parkinson’s disease usually experience motor symptoms several years after the onset of movement symptoms.

• REM sleep behavior disorder (RBD) is common in all three diseases. However, RBD is typically more common in the early stages of Lewy body dementia than in the early stages of Alzheimer’s disease. In Parkinson’s disease, RBD typically develops after or alongside motor symptoms (typically five to 10 years after diagnosis).

The Path Towards Early, Accurate Lewy Body Dementia Diagnosis

Accurately diagnosing Lewy body dementia early is essential for patients to receive the right medical care and avoid receiving incorrect and/or potentially harmful treatment. Early detection also allows patients to take the time to plan their medical care, participate in clinical trials, build a support system, and arrange legal and financial affairs. 

To obtain an early diagnosis, it’s important for healthcare providers to routinely assess the neurocognitive function of their patients, regardless of age. Longitudinal monitoring of neurocognitive function can help healthcare providers detect changes as they occur versus after significant symptoms are present. 

Even with earlier, more frequent neurocognitive testing, there are still significant barriers to obtaining an accurate diagnosis. Currently, healthcare providers rely on outdated pencil and paper cognitive tests. These assessments only test a small subset of neurocognitive domains and often produce noisy, highly variable data that lacks the specificity and granularity needed to paint a true, detailed picture of neurocognitive function and, consequently, make a diagnosis without the use of expensive and/or invasive diagnostic tools.

As neurological diseases can present with similar cognitive and functional symptoms, it’s necessary to utilize neurocognitive assessment tools that assess a wide range of neurocognitive domains at a highly granular level—and digital technologies may be the solution.