Scientists identify physical change that could signal dementia years before diagnosis

New findings suggest physical changes may be some of the early clinical markers for dementia, regardless of genetic risk

Frailty is largely considered one of the many inevitable consequences of ageing, but it could also be an early indicator of dementia, according to new research led by the University of Queensland.

The latest findings, published in the Journal of Neurology, Neurosurgery and Psychiatry, found that older adults living with frailty were diagnosed with dementia two to three years earlier on average than their less frail peers.

The effects were more pronounced still in those without the brain changes typically linked to the condition, who developed dementia five to six years earlier than expected.

Dr David Ward, of UQ’s Frazer Institute, who co-authored the study, said the findings challenge the assumption that frailty is simply a downstream effect of poor health or advancing age.

Instead, he suggested it could play an active role in shaping how and when dementia develops. It’s worth noting that the link holds regardless of genetic risk.

Co-author Tom Strating, a medical student at Maastricht University, explained that carriers of the APOE4 gene variant - already known to raise Alzheimer’s risk - were affected by frailty in much the same way as non-carriers.

Patients with fewer dementia-related brain changes may typically expect a later onset; but the study suggests that this advantage is significantly eroded in those who are frail.

It adds to a growing body of evidence linking frailty and dementia risk.

In 2017, an analysis of the English Longitudinal Study of Ageing involving more than 8,700 older adults found that frail participants faced substantially higher dementia risk than non-frail counterparts, while more recent genetic research had traced elevated frailty levels back as far as 20 years before Alzheimer’s diagnosis.

But the study stops short of establishing causation, with researchers describing it solely as an association, not proof that frailty directly triggers dementia.

Reverse causality remains a live question; it is not yet clear whether frailty precedes brain decline, results from it, or both.

Dr Ward noted that frailty is often preventable and treatable, with strength training, good nutrition and social engagement all shown to delay or even reverse its progression.

Tracking frailty over time could therefore offer clinicians a new opportunity to catch dementia earlier and potentially intervene sooner.