Why timely diagnosis of dementia matters

TIMELY diagnosis of dementia is an increasingly prevalent call to arms in modern medicine, but to many practising clinicians it may seem like a confusing or even fruitless concept, especially in the continued absence of any disease-modifying therapies.

Assuming it is disclosed carefully, timely diagnosis is said to be beneficial, and even a human right – so much so that it is advocated by the new 2016 Australian clinical practice guidelines on dementia.

One may wonder what the word “timely” means: here, I refer specifically to a diagnosis made once dementia is adversely affecting the lives of patients or those around them. It differs conceptually from “early” diagnosis – this term commonly alludes to the preclinical discovery of markers of future neurodegeneration in people who are asymptomatic, via community screening or ‘case finding’ (a strategy which cannot currently be justified, and is not discussed here).

Despite guidelines and reported benefits, delays in timely diagnosis of dementia are common; perhaps only 50% of cases are recognised. The incidence of dementia approaches 2% in older people (aged over 65 years), equating to 68 000 new cases annually in Australia. In the UK, specialist resources available to assess such large patient numbers are described as “manifestly ineffective”, and recent Western Australian data suggest that only 29% of community dementia cases ever access a dedicated memory clinic. As such, although guidelines suggest specialist assessments, a significant diagnostic burden will still befall GPs if we are to avoid neglecting patients not engaging with specialist memory services. In recognition of the limited access to geriatricians (compared with the high numbers of incident cases in the community), efforts have been made recently in Victoria (here and here) to consider how GPs may be assisted to provide diagnosis of dementia, a complex and nuanced process.

Patient risk factors for remaining undiagnosed include social isolation, advanced age and earlier disease. At clinician level, barriers to timely diagnosis include time pressures, lack of knowledge or diagnostic confidence, fear of patient distress following disclosure, and concerns about a lack of disease-modifying therapies (see here and here). The process is very complex and nuanced for GPs. A systematic review on the topic noted that until the case for dementia screening becomes more compelling, efforts to promote timely detection should focus on removing barriers to diagnosis.

Regarding barriers to diagnosis, a lack of buy-in is likely to be a significant factor.

Doctors seek firm understanding of the purposes of what they do, and want to know that there is evidence of positive outcomes from any particular diagnostic pursuit they embark on. They typically want clear answers to the question “why does this matter?”, especially in circumstances where diseases remain incurable. Many doctors are satisfied with evidence of either clinical or systemic benefits, or both, that may arise from an intervention that they are asked to undertake, but may lose persistence if the task appears little more than academic.

I vividly remember, early in my advanced training as a prospective geriatrician, sitting in a memory clinic asking patients to copy cubes, draw clocks and repeat phrases, and wondering: “what exactly is the purpose of all of this?”. I subsequently spent time searching for evidence (if any) of benefits from the process of dementia diagnosis.

However, I wanted to consider if “benefits” of timely diagnosis of dementia were more widespread than self-evident notions such as “it allows future planning” or “it validates the concerns of carers”. Indeed – given the modern health-economic climate – I also wondered if timely diagnosis associates with fiscal outcomes such as “hospital avoidance” or “economic savings to health budgets”.

In short, it strikes me that, if we aspire to give most incident cases “a timely diagnosis of dementia” into the future, generalist doctors in primary and secondary care ought to be provided with clear (clinical and even quantitative) reasons why dementia diagnostics truly matter, when this may not always be obvious.

So, what are the potential benefits of a timely diagnosis of dementia?

We know that undiagnosed neurocognitive disorders see 2.5–3.4 times more hospital admissions, and 3.2 times higher hospital costs than those diagnosed. Leaving patients undiagnosed in the community – and instead piecing together dementia diagnoses within hospital walls – results unsurprisingly in long hospitalisations; two recent studies (here and here) showed length of stay increases of 9–12 days per case, and in Australia, average length of stay is more than tripled. Patient morbidity and economic cost thus rise in tandem.

Even if we accept neurodegenerative dementia’s incurability, there are at least seven factors underpinning both the clinical and fiscal benefits achievable simultaneously via a timely diagnosis:

• Many causes of cognitive impairment are eminently manageable if discovered or postulated. Regarding Alzheimer’s disease specifically, early treatment with cholinesterase inhibitors may maintain patients in the “mild” severity stages for longer – a stage at which both cost and health-related quality of life (HRQoL) are at their least problematic. From the perspective of hospital avoidance, recent Victorian data suggest that chronically ill community patients in the lowest quartile for HRQoL are 58% more likely to use emergency departments (EDs), and so using cholinesterase-inhibitors to halt downhill progression of Alzheimer’s (with its concomitant reduction in quality of life) may be roundly beneficial. Further cost-effectiveness studies on Alzheimer’s disease conclude that a high-quality diagnosis and early treatment is beneficial to patients and society by virtue of delaying institutionalisation. Initial costs of diagnosis may ultimately be offset by net savings exceeding $10 000.
• Community diagnoses of dementia may mobilise carers to assist patients with medication adherence. Given that 20–30% of all national acute hospital admissions in older patients are drug-related (a sobering statistic), any strategy augmenting medication safety demands attention. If dementia is formally diagnosed, family members are more likely to take responsibility for monitoring medication. One can easily imagine an older person living alone whose amnesic state translates to either forgetting to take their diuretic, or conversely taking it six times in one morning, having forgotten it was only taken 20 minutes earlier; such a person is more likely to be assisted with medication if family or carers shift their mindsets from “she is forgetful and grumpy, but she is just old” to “she has a formally diagnosed dementia, a brain disease that is neither her fault, nor just normal ageing”. Such assistance (with, say, a diuretic) has potential to reduce substantial morbidity and cost – for example, by avoiding critical pulmonary oedema.
• Iatrogenesis via inappropriate prescribing is less likely with rigorous diagnostics. For example, failing to detect Parkinson-plus syndromes may result in serious harm if medications known to precipitate drug-induced parkinsonism are prescribed to relieve symptoms – such as metoclopramide, for nausea, or antipsychotics used to treat undifferentiated “agitation”. Acute secondary parkinsonism may persist for weeks following drug cessation, risking prolonged admissions and morbidity.
• Diagnosis may be accompanied by deep phenomenological understanding of what it is like to have dementia, and this itself has potential to reduce length of stay for incidental hospital admissions. Through the process of assessing cognition, especially if done frequently and using more than the mini mental-state exam, one may increasingly appreciate the essence of what happens to a person with advancing dementia – with its frightening array of amnesias, aphasia and agnosias. Being unsure where you are, how you came to be there, and perceptually struggling to understand what you hear (eg, words, noises and music) or see (eg, people, text, objects, money, landmarks and even body language) may be markedly distressing. Many hospital behaviours deemed challenging – such as wandering, shouting and soiling – originate simply from disorienting features of insidious brain damage, rather than through some sort of ill-defined character flaw or calculated attempts by geriatric patients to be “difficult”. Length of stay can spiral if patients are philosophically viewed as deliberately “aggressive” or “intrusive”, as they may not be able to be discharged (“the nursing home won’t take them … too agitated”); further, sedatives or restraints may be used liberally, risking critical complications ranging from falls on the ward to neuroleptic malignant syndrome. A formal diagnosis may thus foster greater understanding of why afflicted patients behave as they do, affording safer, cheaper and less prolonged hospital management.
• Access to dementia-related medications and services may be conditional on pre-specified diagnostics. In Australia, access to cholinesterase inhibitors at government-subsidised prices depends on a specialist diagnosis of Alzheimer’s disease; likewise, access to a national program tackling behavioural concerns is only granted following diagnosis.
• Avoidance of costly, predictable community crises in isolated people with advancing dementia – including self-neglect, impending financial ruin, car accidents and fires – may require the occasional involuntary imposition of substitute decision making. At baseline, everyone is assumed to have autonomous capacity to behave as they please. Therefore, lawfully permitting the wider society to judge that capacity has been lost is a profound matter, and accordingly should, from the outset within a legal context, rest on a formal diagnosis of non-reversible dementia. Imposing guardianship on patients with dementia may save “life and limb”, but a formal neurocognitive diagnosis is required to initiate this protective action.
• Residential aged care facilities (RACFs) frequently send residents to acute hospitals, and the risk of ED use is 25% greater in those with undiagnosed dementia. In Australia, a specialist diagnosis of dementia generates greater funding for RACFs per client, via a government funding assessment tool (ie, Aged Care Funding Instrument). Thus, a timely diagnosis may concurrently reduce the risk of ED presentations while bolstering RACF funds to enable improved staffing with skilled nurses.

Timely dementia diagnoses may concurrently benefit both patients and society via avoidance of catastrophic and prolonged hospital admissions. Further, community care may improve in various ways, such as considering disease reversibility, improving efficacy of comorbidity management via family support, garnering services, imposing guardianship where needed and reducing iatrogenesis.

Doctors may increasingly heed calls for timely diagnosis if forearmed with a concise list of reasons why this mission matters.

Dr Toby Commerford is a consultant in geriatric medicine at the Royal Adelaide Hospital, is the visiting rural and outback geriatrician to Port Augusta and Murray Mallee, and is the course co-ordinator for rural 5th year medical student teaching in Geriatrics at the Discipline of Rural Health, University of Adelaide.

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