A Parkinson’s disease subtype characterized by postural instability and gait disturbance, usually referred to as PIGD, is associated with small amounts of bleeding in the brain, called cerebral microbleeds, a study reports.
The study, “Cerebral Microbleeds are Associated with Postural Instability and Gait Disturbance Subtype in People with Parkinson’s Disease,” was published in the journal European Neurology.
Cerebral microbleeds are easily detectable on MRI (magnetic resonance imaging) scans, and as many as a third of people with Parkinson’s disease have them. However, it isn’t clear what — if any — role this bleeding might play in the progression of the disease.
To gain some insight into this association, researchers reviewed records from Parkinson’s patients who had been treated at Shuang Ho Hospital in Taiwan between 2009 and 2017. They analyzed the records from 134 people with early- and mid-stage Parkinson’s for whom MRI data, as well as demographic and disease information, were available. The patients’ average age was 69.5 years, and slightly more than half were female.
Cases of Parkinson’s disease can be divided into three groups based on what motor symptoms are most prevalent: tremor dominant (TD; the subtype associated with tremors), akinetic rigidity (AR; slow and stiff movements), and postural instability and gait disturbance (PIGD; difficulty standing/walking).
In the study cohort, 35.8% of patients were in the TD subtype (mainly females), and 16.7% of these patients had cerebral microbleeds. The AR subtype made up 47.8% of the study cohort (male predominant), and 39.1% of these patients had microbleeds. The PIGD subtype made up 16.4% of the cohort (mildly female predominant), but more than half of these patients had cerebral microbleeds, suggesting an association between microbleeds and this subtype of motor disturbances in Parkinson’s disease.
The researchers determined that the association between the presence of cerebral microbleeds and the PIGD subtype was statistically significant, even after accounting for factors such as age and sex, which varied among subtypes. People with the PIGD subtype of Parkinson’s disease were slightly older than those in the other two groups.
Microbleeds in certain parts of the brain, such as the thalamus, were found to be significantly associated with the PIGD subtype, while microbleeds in other areas were not. The thalamus is involved in sensory and motor signal relay and also coordinates the regulation of consciousness and sleep.
Interestingly, the overall frequency of cerebral microbleeds detected in the cohort was quite high — 33.6%. The researchers believe that this high frequency of detection compared with other studies was due to their use of more modern equipment, which was able to identify microbleeds that would have been missed previously.
However, this study is correlational — additional research will need to be done to determine whether cerebral microbleeds play a role in the development of Parkinson’s and/or the PIGD subtype in particular. Such studies, the researchers concluded in their paper, “may be beneficial in identifying new disease modification treatments.”