Monica Mathys, PharmD, BCPP, CGP
This session can be purchased in CPNP University.
It is predicted the number of patients diagnosed with Parkinson’s Disease (PD) will increase as the aging population continues to grow, and most clinicians will likely be involved in the care of these patients. Jack Chen, PharmD, BCPS, CGP, presented the most current information regarding the pathology, diagnosis, and management of PD at the CPNP 2016 meeting in his presentation entitled, Current Understanding and Management of Parkinson’s Disease: Five New Things. Dr. Chen is currently a Professor and the Department Chair of Pharmacy Practice at Marshall B. Ketchum University College of Pharmacy.
Pathology and Diagnosing Parkinson’s Disease
Dr. Chen began his presentation discussing the three core motor symptoms and other supportive signs and symptoms associated with PD.1 When looking at the clinical progression of the disease, a pre-motor/prodromal period (often involving symptoms such as constipation, REM behavior disorder, hyposmia and depression) can exist for up to 20 years before tremor, rigidity, or bradykinesia are detected.2 While reviewing the etiology and risk factors of the disease, Dr. Chen reviewed results of a 2012 meta-analysis showing family history, pesticide exposure, and head injury appear to be risk factors while smoking and coffee consumption have shown to be associated with a lower risk of PD.3
In regards to the pathology of PD, research has shown that Lewy bodies, which are an accumulation of alpha-synuclein protein, infiltrate into the CNS and damage neurons. Dr. Chen’s presentation pointed out that Lewy body CNS distribution first occurs in the medulla oblongata and olfactory bulb (which relates with the pre-motor and motor symptoms) and then eventually filters into the cortical regions (which relates with the emotional and cognitive disturbances).4 Current research has also discovered that alpha-synuclein is not only found in the CNS of PD patients but also exists peripherally such as in the nasal epithelium, submandibular glands, and colon.5 Although alpha-synuclein is pathogenic in the disease, there are ongoing studies investigating whether alpha-synuclein can also be used as a disease modifying therapy (possibly as a vaccine) for PD.6
New Drug Therapies for Motor and Non-Motor Symptoms of Parkinson’s
The last half of Dr. Chen’s presentation reviewed the newer medication products available for PD management. Both carbidopa/levodopa extended-release capsules and the continuous intrajejunal carbidopa/levodopa infusion are two new products that may be helpful for motor symptoms in advanced PD.7-8 Dr. Chen also discussed the clinical data for droxidopa which is approved for neurogenic orthostatic hypotension and for pimavanserin which is the first non-dopamine antagonist antipsychotic approved for PD associated psychosis.9-10
Take Home Message
In the future, clinicians are likely to take a multimodal approach when diagnosing PD which may include PET scan results, genetic testing results, assessing for diagnostic motor symptoms and olfactory dysfunction, and testing for alpha-synuclein in the skin and colon.2
Several treatments are available for the motor and non-motor symptoms of PD including two new carbidopa/levodopa products that may be helpful in advanced PD. There are studies currently in progress investigating different agents, including alpha-synuclein, as disease modifying therapies.
References