Parkinson’s patients more prone to hospital delirium, study finds
Patients face higher risk of dementia, institutionalization, death
People with Parkinson’s disease are nearly twice as likely to experience delirium during hospital stays as hospitalized older adults without the neurodegenerative disease, according to a study from Newcastle University.
Data showed that delirium, which often goes undocumented in Parkinson’s, was reported in as many as two-thirds of hospitalized Parkinson’s patients. It was also significantly associated with a higher chance of dementia, institutionalization, and death in the year following discharge.
“We have found that delirium can have a serious effect on the lives of people with Parkinson’s and their loved ones,” study leader Rachael Lawson, PhD, Parkinson’s UK senior research fellow, said in a society press release.
Parkinson’s UK funded the study.
“It is a distressing condition that is so often unrecognized and we are often unable to tell families what to expect in the future,” Lawson said. “I hope that our study will help to pave the way to greater awareness of delirium in Parkinson’s and to the development of better tests.”
The study, “Delirium is more common and associated with worse outcomes in Parkinson’s disease compared to older adult controls: results of two prospective longitudinal cohort studies,” was published in Age and Ageing.
‘Urgent need’ for focus on delirium in Parkinson’s
Becky Jones, PhD, research communications manager at Parkinson’s UK, said the study “highlights the urgent need for better ways of measuring delirium in people with Parkinson’s, and being able to treat it sooner.”
Many people with Parkinson’s, a progressive neurological disease best known for its motor symptoms, experience changes in mental state, including hallucinations and delirium.
Delirium, a state of sudden confusion that affects how well people focus and stay aware of what’s going on around them, can happen as the healthy brain ages. It can be difficult to identify because many of its symptoms overlap with those of Parkinson’s.
“In older adults, delirium has been associated with increased risk of institutionalization, dementia, and mortality,” the researchers wrote. “However, there is a paucity of similar evidence in PD [Parkinson’s disease].”
To understand the frequency of delirium in hospitalized Parkinson’s patients and its potential association with adverse outcomes, the researchers drew on data from 121 Parkinson’s patients and 199 older adults without Parkinson’s who stayed at Newcastle hospitals.
Data from Parkinson’s patients came from the Defining Delirium and its Impact in Parkinson’s Disease study, and data on the control group came from the Delirium and Cognitive Impact in Dementia study.
A total of 173 participants had available data on at least one of the three adverse outcomes evaluated: death, institutionalization, and dementia.
The Parkinson’s patients had a median age of 77, while the control group’s median age was 82. Parkinson’s patients were more likely to have dementia at hospital admission (18.2% vs. 9.5%).
Parkinson’s patients were also twice as likely to experience delirium in the hospital (66.9%) as older adults without the disease (38.7%).
Higher chance of dying within a year
In both the Parkinson’s and control groups, those with delirium had significantly lower cumulative survival probability one year after leaving the hospital. Delirium was significantly linked to a threefold higher chance of dying within a year of discharge in Parkinson’s patients. No significant association was observed in the control group.
This altered mental status also was significantly associated with a higher likelihood of institutionalization among Parkinson’s patients — by 10 times — but not among older adults. Nearly half (48.1%) of surviving Parkinson’s patients not in care homes before delirium moved to care homes within a year, compared with 5.9% of those without delirium and 16.3% of controls who experienced delirium.
Among surviving participants who were free from dementia at admission, the chances of developing dementia at one year were significantly higher for those who experienced in-hospital delirium than in those who didn’t.
Delirium was significantly associated with a six times higher chance of dementia in those with Parkinson’s and a 13 times higher likelihood of dementia in older adults without the disease.
Moreover, a significantly greater proportion of Parkinson’s patients with delirium experienced at least one adverse outcome relative to those without delirium (70% vs. 27.5%) and older adults with delirium (58.8%).
“Delirium increased the risk of a negative outcome by fourfold in PD participants and sixfold in controls,” the team wrote.
These findings indicate that “missing signs of delirium in people with Parkinson’s can have serious consequences,” Jones said. “Better tests to define and monitor delirium, that take into account symptoms of Parkinson’s, could potentially help avoid these adverse effects,” she said.
“There is an urgent need for further research in people with [Parkinson’s] to determine how best to diagnose and manage delirium, including clinical trials to reduce the risk of adverse outcomes,” the researchers wrote.