Parkinson’s Early Signs: Don’t Ignore These Surprising Symptoms

Our understanding of the brain’s complexities and its impact on our lives continues to evolve. Daily scientific studies aim to deepen this understanding and improve quality of life. Recent research into Parkinson’s disease suggests that symptoms may manifest years, even decades, before a formal diagnosis.

Beyond Tremors: Recognizing Early Signs

The most recognized symptom of Parkinson’s disease is often a tremor in limbs, particularly the hands, when at rest. However, a diagnosis doesn’t necessarily require this symptom; approximately 20 percent of those with Parkinson’s do not experience tremors.

Parkinson’s is one of the most prevalent neurological disorders globally. Projections estimate that 25.2 million people worldwide could be living with the disease by 2050. While genetic factors are believed to play a role in 10 to 15 percent of cases, the other causes remain unknown. Though treatments can manage symptoms, there is currently no cure for Parkinson’s. Researchers have made significant progress in understanding the earliest stages of the disease over the past two decades.

Rachel Dolhun, a neurologist and medical advisor to the Michael J. Fox Parkinson Research Foundation, describes Parkinson’s as a movement disorder because it affects motor skills. However, she emphasizes, “But Parkinson’s has a non-movement side to it as well. We’ve long thought of Parkinson’s as a movement disorder, but now we’re seeing that this disease affects the whole body in different ways.”

Symptoms Appearing Years in Advance

Neurologists typically diagnose Parkinson’s based on prominent symptoms like slowness, rigidity, and resting tremors. However, non-motor symptoms, such as constipation and loss of smell, often appear more than 10 years before these motor signs. This early stage is referred to as the “prodromal” phase.

Professor Ronald Postuma of McGill University explains, “Parkinson’s is a slow disease, and we’re starting to realize just how slow it can be. It progresses in the brain for years before it reaches the point where doctors can make a diagnosis.”

Parkinson’s disease damages dopamine-producing cells in the brain. Dopamine is a chemical crucial for transmitting signals between cells, and for controlling movement and coordination. By the time motor symptoms appear, 50 to 70 percent of the neurons in the substantia nigra – a brain region vital for voluntary movement – have already died.

Dolhun stresses that not all Parkinson’s patients will experience these early symptoms, but acknowledges, “But we know that in some, these can be the earliest signs.”

Loss of Smell: A Significant Indicator

Loss of smell, known as anosmia, can be a temporary symptom of a cold or, in some cases, a lasting effect of COVID-19. However, approximately 90 percent of Parkinson’s patients eventually lose their sense of smell. This symptom can appear decades before motor symptoms develop.

According to Professor Postuma, “Loss of smell is happening about 20 years before we make a diagnosis of Parkinson’s, according to our estimates.” He adds, “People who lose their sense of smell are five times more likely to develop Parkinson’s. People generally don’t notice they’re losing their sense of smell because it happens so gradually.”

The exact cause of smell loss in Parkinson’s and why it’s an early indicator remains under investigation. One theory suggests the disease begins in the olfactory bulb, the brain region responsible for processing smells, with abnormal proteins causing damage to neurons.

Other Potential Early Warning Signs

Beyond loss of smell, researchers are investigating other potential early indicators. REM sleep behavior disorder, where individuals physically act out their dreams, is a significant concern. Between 50 and 70 percent of those with REM sleep behavior disorder will eventually develop Parkinson’s or Lewy body dementia within 5-10 years.

Chronic constipation, lasting for weeks or longer, affects about two-thirds of Parkinson’s patients, as the disease can impact cells in the digestive system. Studies have shown that individuals with long-term constipation have twice the risk of developing Parkinson’s. Research suggests abnormal protein clusters are found in the intestines of Parkinson’s patients.

Postural hypotension, a drop in blood pressure upon standing, is another potential early sign. While often caused by dehydration or medication, chronic postural hypotension may indicate a neurological issue, with nearly half of those affected eventually diagnosed with Parkinson’s or a related condition.

Frequently Asked Questions

What is the prodromal stage of Parkinson’s?

The “prodromal” stage refers to the early phase of Parkinson’s disease, where non-motor symptoms like constipation and loss of smell may appear, often more than 10 years before the typical motor symptoms like tremors.

Is a loss of smell always a sign of Parkinson’s?

No, loss of smell can be caused by many factors, such as colds or COVID-19. However, 90 percent of Parkinson’s patients eventually experience a loss of smell, and it can occur decades before motor symptoms appear, increasing the risk fivefold.

Can Parkinson’s be prevented?

Currently, there is no known way to prevent Parkinson’s disease. However, recognizing early symptoms and seeking medical evaluation may allow for earlier intervention and management of the condition.

Considering the subtle and often overlooked early signs of Parkinson’s disease, what steps might you take to proactively monitor your own neurological health?