A study by neurologists and Parkinson’s experts showed that a simple sobriety “tandem gait” test could be an important first step in predicting which patients with early stage Parkinson’s disease have an elevated risk for falling.
People unable to walk heel-to-toe for 10 steps – akin to the “walk the line” sobriety test used by police – should be closely monitored and counseled about their greater risk for falling, said senior study author Carlos Singer, M.D., director of the Division of Parkinson’s Disease and Movement Disorders at the Miller School of Medicine. The study also revealed a fall risk in many people who passed standard assessments but failed the tandem gait test.
Importantly, the tandem gait test is not currently part of the routine evaluation in this patient population. “It’s an earlier sign. So our proposal is that this test should be incorporated into the routine staging of the disease,” Dr. Singer said.
Neurologists typically classify Parkinson’s disease from mild to severe using the Hoehn and Yahr (H&Y) scale. For example, H&Y 1 means the disease affects only one side of the body, H&Y 2 affects both sides, and H&Y 3 describes someone who fails the standard ‘anterior-posterior’ balance test. “This means the disease has really begun to affect good balance, and this person’s fall risk is greater,” added Dr. Singer, who is also professor of neurology at the Miller School.
Jason Margolesky, M.D., assistant professor of neurology and first author of this report, Dr. Singer and their colleagues in the Division of Movement Disorders assessed 102 consecutive people with Parkinson’s disease. They performed the tandem gait test, an anterior-posterior test and asked participants about any history of unsteadiness or falls. They report the findings of their cross-sectional study in the journal Parkinsonism and Related Disorders.
To complete the anterior-posterior balance assessment, a neurologist approaches a standing patient from behind. The physician places their hands on the patient’s shoulders and warns them they are about to pull them backwards.
A person with normal balance will take one or two steps backwards to prevent themselves from falling. In contrast, a person with H&Y stage 3 disease needs to take three or more steps to recover their balance.
Perhaps not surprisingly, all nine patients who failed the anterior-posterior test and were classified H&Y 3 also had an abnormal tandem gait test in the study.
Interestingly, a majority of the H&Y 2 patients also failed the tandem gait assessment.
A total of 64% of the 63 participants who passed the anterior-posterior test failed to walk heel-to-toe for 10 steps without faltering.
“We believe we have identified a sign for risk of falling before the sign that is routinely used today,” Dr. Singer said.
A poor performance on the tandem gait test could mean paying more attention to balance, referring a person to physical therapy, and/or considering levodopa to help improve balance, Dr. Singer said.
“A lot of it is also incorporating consciousness into your balance. I tell my patients they have to now be conscious when they walk and when they turn. It is a little more energy consuming, but if it saves you from a fall, it’s worth it.”
The findings also carry implications for researching the tandem gait test in future clinical trials of medications to help people with Parkinson’s disease maintain or improve their balance.
The researchers also would like to monitor balance issues in people with Parkinson’s disease over time. This longitudinal study would allow them to verify that instability on the tandem gait test always precedes an abnormal performance on the anterior-posterior balance assessment.