Managing multimorbidity can help people with dementia live better for longer

Much attention has been paid to the development of new drug treatments for Alzheimer’s disease. Interventions to target the pathophysiology of the most common form of dementia are essential to tackle its rising public health burden. Amid intense debates about the effectiveness of anti-amyloid treatment for Alzheimer’s disease1 lies a stark reality highlighted by our study published in The BMJ (doi:10.1136/bmj-2024-083034).2 While dementia incidence is decreasing, prevalence continues to rise in the US, and more than one in 10 older people in the US now have a dementia diagnosis.

People are living longer and people with dementia are no exception. The scientific and medical communities must redouble our efforts to reduce the burden of chronic disease among people with dementia. Global public health resources must anticipate and proactively deploy resources to tackle the increasing burden of dementia.

People with dementia rarely have dementia alone. The presence of other severe chronic conditions, such as cardiovascular disease and diabetes mellitus, is high compared to adults without dementia.3 Our study estimates that more than 40% of people with dementia have cerebrovascular disease, 30% have depression, and more than 80% have hypertension. Multimorbidity is not only associated with dementia risk45 but it also complicates medical management. General practitioners and geriatricians alike struggle to manage the complex burden of multiple chronic conditions, which is often exacerbated by cognitive impairment.6 These comorbid conditions each carry their own additive or multiplicative effects that reduce quality of life.

As people with dementia live longer, developing thoughtful strategies that balance the benefits of chronic disease prevention and management with the potential harms from medical interventions will become increasingly important. We will need to find such medical interventions with the right balance, and these will likely differ for each person.

There is a clear need for additional clinical practice guidelines tailored to people with dementia. For example, the American Geriatrics Society Beers Criteria7 provides guidance on medications that may be harmful in older people. However, this guidance has not been systematically evaluated among people with dementia, who are at higher risk of many of the complications of potentially inappropriate medication use, including falls, worsening cognitive impairment, and delirium.89 Common sense and guidance dictates against people with dementia using anticholinergic medications, and there are black box warnings against using antipsychotics. But the risk/benefit profile of many other commonly used drug treatments may be more challenging to assess, especially those necessary to manage other severe medical conditions.

Clinical trials targeted at person centred management of chronic disease multimorbidity among people with dementia are sorely needed. Currently, clinicians, patients, and families lack clear evidence on the best approach to treat common conditions like hypertension and diabetes among people with dementia. The expected benefit and potential risk profile differs between people with dementia and those of similar age without dementia. Pragmatic clinical trials among adults with dementia in the community and long term care facilities are urgently needed to provide the necessary guidance on how to manage multiple chronic medical and psychiatric morbidities.

Additionally, policymakers and clinicians need to anticipate the effect that the rising prevalence of dementia will have on health systems. Access to general medical and specialised resources must be considered. For example, a recent study showed that 87% of people with dementia in the US received care from a primary care physician, while psychiatrists, neurologists, and geriatric specialists each made up less than 3% of the clinicians providing care.10 Access to specialty care will be increasingly important to ensure accurate diagnosis, assist in management of complex medical and psychiatric morbidity, a and determine eligibility for emerging dementia treatments. As dementia prevalence grows, there will be an increasing need for long term care services in home based and facility based settings, which is likely to collide with an existing shortage of direct care workers in many countries.1112

We cannot wait until dementia prevalence climbs further, as it will be too late to mobilise resources. We need to commit resources to research, workforce development, and infrastructure now.