Parkinson’s disease (PD) symptoms can broadly be divided into two categories – motor and non-motor. It turns out that non-motor symptoms often precede motor symptoms, sometimes by decades.
Rebecca Gilbert, M.D., Ph.D.
Chief Scientific Officer, American Parkinson Disease Association
Motor symptoms are ones that affect movements and include rest tremor, stiffness, slowness, difficulty with balance, shuffling gait, expressionless face, and others. Non-motor symptoms are ones that do not affect movement and include mood disorders, cognitive disorders, sleep disorders, blood pressure variability, constipation, urinary frequency, pain syndromes, and others.
It turns out that non-motor symptoms often precede motor symptoms, sometimes by decades. Typically, there are certain non-motor symptoms that are the most likely to appear early. These include:
- Loss of smell
- Sleep disorders (specifically rapid eye movement behavior sleep disorder, RBD)
The tricky thing is, these four symptoms are quite common in the general population so we cannot assume, for example, that everyone experiencing constipation has PD. However, once motor symptoms develop, it is incredibly common for people with PD to look back and be able to identify a non-motor symptom that was present first.
If you or someone you know is exhibiting the classic early non-motor symptoms of PD and you’re concerned about it, your next step should be to make a non-urgent appointment with a neurologist. This doctor will conduct a neurological exam, the results of which may be normal or may show subtle motor symptoms consistent with PD.
If there are no motor symptoms present, it is possible that the doctor will recommend you be followed yearly by a neurologist to see if there is emergence of motor symptoms. There, unfortunately, is no drug that has been proven to delay or prevent progression of symptoms of PD. However, there is evidence that exercise is neuroprotective, potentially affecting the progression of the disease. Therefore, after a visit to a neurologist, it may be beneficial for a person who is experiencing only the non-motor symptoms of PD to start or increase their level of exercise. For information on exercise and wellness for people with PD, the American Parkinson Disease Association has a free Be Active & Beyond booklet.
The first motor symptoms
Early motor symptoms of PD (which usually, but not always, start after the appearance of at least one non-motor symptom) can be a subtle rest tremor of one of the arms or hands (sometimes of just one finger). A rest tremor is one that occurs when the limb is completely at rest. If the tremor occurs when the limb is suspended against gravity or actively moving, this may still be a sign of PD, but may also be a sign of essential tremor.
The initial motor symptom of PD may be a sense of stiffness in one limb, sometimes interpreted as an orthopedic problem (e.g. frozen shoulder), perhaps noticed when trying to put on your coat. You may experience a slowness of one hand or a subtle decrease in the dexterity of one hand. Or perhaps one arm does not swing when you walk, or one arm is noticeably less active than the other when performing tasks. A family member may notice that you blink infrequently or have less expression in your face and voice. These motor symptoms may be very subtle.
The bottom line is if you are concerned that you may have an early motor or non-motor symptom of Parkinson’s disease, make an appointment with a neurologist for a neurologic exam to discuss your concerns. Try to make note of how often the symptoms affect you so you can give the doctor the most information possible.
For more information and support, contact the American Parkinson Disease Association at www.apdaparkinson.org or 800-223-2732.