Early Symptoms of Parkinson’s Disease Evident Years Before Diagnosis, Study Shows
Shortcomings in daily activities such as housework, meal preparations, money management, and shopping, which require both motor and non-motor skills, precede difficulties in more physically oriented daily activities in patients with pre-diagnostic Parkinson’s disease, according to a study published in the scientific journal Brain.
This is an important finding because it can help physicians diagnose Parkinson’s disease earlier and could help manage the condition better.
The study “Trajectories of prediagnostic functioning in Parkinson’s disease” is the first that describes the order in which motor and non-motor shortfalls affecting daily functioning in Parkinson’s disease patients happen.
The team of researchers led by Arfan Ikram, MD, PhD, of the Erasmus MC University Mecial Center Rotterdam in the Netherlands. studied the trajectory of daily functioning and motor and non-motor functions in the 23 years before the diagnosis of Parkinson’s disease. He did so by implementing a nested case-control study within the Rotterdam study, which analyzed almost 8,000 people living in Ommoord in the Netherlands, aged 55 and older.
The researchers repeatedly assessed the daily functioning of the participants between 1990 and 2013 using the Stanford Health Assessment Questionnaire and the Lawton Instrumental Activities of Daily Living Scale.
To assess potential pre-diagnostic motor function, the researchers used slowness or loss of muscle movements, tremor, rigidity, imbalance, or abnormal posture.
Finally, they assessed non-motor features of Parkinson’s disease, including cognition, mood, and autonomic function using several standardized tests, including the Mini-Mental State Examination, the Stroop Test, the Letter-Digit-Substitution Test, the Word Fluency Test, Center for Epidemiological Studies-Depression Scale, Hamilton Anxiety and Depression Scale, blood pressure, and laxative use.
The researchers also followed the participants with repeated in-person examinations, and by accessing their medical records.
In this period of time, 109 people were diagnosed with Parkinson’s disease. The researchers matched every one of them to 10 people of the same age and sex without Parkinson’s disease as a control.
When they compared the daily functioning of people who were later diagnosed with Parkinson’s disease with those who were not, the researchers found that from seven years before diagnosis onward, people who later were diagnosed with Parkinson’s disease more often had problems in instrumental daily activities. They also more frequently showed signs of movement difficulty and slowness, tremor and subtle cognitive deficits.
In the five years before diagnosis, people who later were diagnosed with Parkinson’s disease developed additional motor problems such as imbalance, rigidity and abnormal posture, and increasingly reported problems in basic daily activities.
Finally, people who later were diagnosed with Parkinson’s disease increasingly reported anxiety symptoms, depressive symptoms, and use of laxatives throughout study follow-up. However, the differences with people who were not diagnosed subsequently with Parkinson’s disease became statistically significant only in the last years before diagnosis.
It already was known that some patients who were diagnosed with Parkinson’s disease had symptoms preceding the diagnosis of the condition. However, this is the first study that describes in detail the sequence of these so-called prodromal symptoms.