Higher Risk of Falls Linked to Longer Disease Duration and PIDG Subtype, Study Suggests

In Parkinson’s patients, the risk of falls increases depending on disease duration and having the postural instability/gait disturbance (PIDG) subtype, but is not signficantly correlated with non-motor symptoms, a study suggests.

The study, titled “Falls in persons with Parkinson’s disease: Do non-motor symptoms matter as much as motor symptoms?,” was published in Arquivos de Neuro-Psiquiatria.

Falls can be a major problem for people with Parkinson’s disease, with some individuals being at greater risk of serious falls. However, identifying a person’s fall risk can be challenging because the risk is affected by a multitude of different factors that may or may not be related to Parkinson’s disease itself.

Intuitively, it may seem that the best predictors of falls are likely related to motor symptoms — after all, falling is associated with moving. But, previous studies have suggested that measurements of motor function aren’t good predictors of falls.

The researchers behind this new study set out to investigate whether including non-motor symptoms, in addition to motor symptoms, would help better predict fall risk in people with Parkinson’s.

The Parkinson’s Disease News Today forums are a place to connect with other patients, share tips and talk about the latest research. Check them out today!

To test this, the researchers assessed 179 people (average age of 64.6 years, mean disease duration of 10.4 years) with Parkinson’s who were seen at the National Institute of Neurology and Neurosurgery in Mexico City. The participants’ clinical history, including fall history in the past year, was taken.

Participants underwent a series of evaluations, including disease state using the Hoehn and Yahr scale, assessment of motor symptoms using relevant parts of the Movement Disorders Society Unified Parkinson’s Disease Rating Scale, as well as non-motor symptoms using the Non-Motor Symptoms Scale.

Overall, 16.8% had experienced a fall in the last year, with just over half of these having experienced more than one fall — the average was 2.5 falls per month. The researchers noted that this is a “very low” proportion of patients who experienced falls (“fallers”), which “could partially be explained by under-representation of advanced forms of the disease,” a limitation of the study.

The researchers constructed statistical models using several types of data that they had collected, with the aim of identifying factors that were significantly over-represented among the fallers — thus, being predictive of falling.

They found that the severity of motor and non-motor symptoms in the participants was not significantly linked with fall risk.

However, the study did find two factors that were linked with fall risk: the first was disease duration. Patients who had experienced symptoms for longer were more likely to fall — average disease duration was 12.8 years in the fallers group and 7.4 years in the non-fallers group.

The second risk factor was having the PIDG subtype (which accounted for 59.8% of the participants), one of the three groups into which Parkinson’s patients can be divided based on their most prominent motor symptoms. The PIDG subtype is associated primarily with difficulty standing and/or walking and is thought to be associated with rapid progression of disease and cognitive dysfunction.

While about half (53%) of the people in the non-fall group had the PIDG subtype, nearly all (93%) of those in the fall group had the subtype.