Understanding Parkinson’s disease

Parkinson’s disease (PD) is a neurodegenerative disorder with an average onset at around 60 years of age. In the UK, the prevalence of PD is about 1/800, with an annual incidence of 1/8000.

Approximately 1% of people over the age of 65 years are affected and a general practitioner will have three to four patients at any one time in their practice so will be familiar with the disease.

We’ve asked one of our top neurologists Dr Dominic Paviour for his expert opinion on the early warning signs of the disorder and which other neurological conditions may mimic the symptoms of Parkinson’s.

What are the early warning signs of Parkinson’s disease?

Parkinson’s disease typically causes a one-sided tremor, most obvious when at rest rather than engaged in an active task. The slowness of movement and muscle stiffness are also typical. The symptoms are often initially quite subtle and emerge slowly over a period of months. It is not unusual in my experience for someone with early-stage PD to have seen a rheumatology specialist for something like a “frozen shoulder” that is actually related to the muscle stiffness caused by PD.

The typical clinical signs of PD that a neurologist will look for are slowness of repetitive movements (bradykinesia), difficulty in initiation of movement (akinesia), and a progressive reduction in the speed and amplitude of sequential movements (i.e. motor decrement or decay), with muscular rigidity and a slow “pill-rolling” resting tremor.

An early sign can be a reduced arm swing on walking, reduced facial expressiveness, a quietening of the voice and smaller handwriting. So-called “non-motor” signs can precede the problems with movement by months or even years and include depression, anxiety, constipation and a particular sleep disorder called “REM sleep behaviour disorder,” whereby an individual may “act out” dreams or start talking in their sleep.
 

What can mimic Parkinson’s disease?

A number of other neurological conditions can mimic PD.

Because the pathology underlying PD results in a loss of dopamine-releasing nerve cells in the brain, anything that has the same effect can result in symptoms that resemble those of PD. Any medication that blocks dopamine receptors can do this and anti-sickness drugs and some of the medicines used to treat depression and psychosis will do this.

Other “neurodegenerative” diseases can resemble PD but may cause earlier problems with balance or more marked problems with control of blood pressure and bladder and bowel function as well as cognitive function. These conditions can initially be difficult to distinguish from typical PD and additional investigations including imaging studies may be recommended.
 

What are the five stages of Parkinson’s disease?

Neurologists use a number of scales and criteria to describe stages of PD. In my experience whilst these have clear utility in the context of observational research studies as well as prospective trials of treatment, on an individual basis they are not especially useful in day to day clinical practice. The key is to understand what the main symptoms affecting a person’s quality of life are and to adjust treatment to try to improve those symptoms.


If you are worried that either you or your loved one is showing early signs of Parkinson’s disease, do not hesitate to book an appointment with Dr Paviour now for an assessment.