Author Affiliations:

IQVIA, The Point, 37 N Wharf Rd, London W2 1AF

Alzheimer’s Disease: A Growing Crisis in an Aging Nation

In January 2025, dementia quietly disappeared from England's NHS Operational Planning Guidance¹, at the very moment the scientific community was delivering the first disease-modifying therapies for Alzheimer's disease, the most common form of dementia, and the most comprehensive evidence yet on prevention. World Brain Day 2026, themed "Brain Health: Access For All"², asks us to confront that disconnect directly. In Alzheimer’s disease, access will not be determined by innovation alone, but by whether health systems can generate and act on real world data to identify patients earlier, understand unmet need, and evaluate whether new interventions deliver meaningful benefit in routine care.

Globally, an estimated 57 million people are living with dementia, a figure rising rapidly as populations age, of which Alzheimer's disease accounts for 60–70% of cases³. The UK reflects that crisis in sharp relief. Around 982,000 people are currently affected, a figure projected to reach 1.4 million by 2040. Over the same period, the cost of care is expected to rise from £42 billion to £90 billion⁴. Yet this trajectory is not inevitable: fourteen modifiable risk factors have been identified across the lifespan, with the potential to prevent or delay up to 45% of cases⁵. Realising that opportunity demands more than clinical innovation; it requires a deeper understanding of how care is delivered and experienced in the real world.

Genuine access does not begin at the point of treatment. It begins with the ability to identify who is at risk, understand how their condition is evolving, and evaluate whether interventions are delivering meaningful benefit. More than a third of people living with dementia in the UK remain undiagnosed⁶, a gap between scientific possibility and clinical reality that only real-world evidence can close. As IQVIA recently argued in "Preventing Dementia Together: A Data-Driven Approach to Early Detection and Risk Reduction"⁷, a data-driven approach is essential if health systems are to identify people earlier, understand local variation in pathways, and move from broad policy ambition to practical, patient-level action.

A Treatment Landscape in Flux

The Alzheimer's pipeline has never been more active, or more complex - and with that complexity comes an even greater need for evidence that goes beyond the trial setting. Advances in blood-based biomarker diagnostics and the emergence of novel therapeutics are reshaping expectations of what is possible in Alzheimer's care.

Disease-modifying therapies reach the UK, but access remains uncertain

Lecanemab and donanemab, the first disease-modifying therapies targeting underlying amyloid pathology, were both licensed by the MHRA in 2024 for adults in the early stages of Alzheimer's disease. However, in June 2025 NICE concluded that neither therapy represented sufficient value for routine NHS use, citing costs five to six times above standard thresholds and benefits limited to a four-to-six-month delay in progression from mild to moderate disease⁸,⁹. In March 2026, following successful manufacturer appeals, NICE confirmed it would re-evaluate both treatments, this time under new, higher cost-effectiveness thresholds and with a mandate to properly account for the impact of Alzheimer's disease on unpaid carers, an aspect the original appraisal was found to have "grossly underestimated"^10,11.

GLP-1 receptor agonists: when biology and clinical outcomes diverge

One of the most closely watched developments has been the investigation of GLP-1 receptor agonists, a drug class originally developed for type 2 diabetes and obesity, for potential neuroprotective effects in Alzheimer’s disease. Preclinical evidence suggests these agents may reduce neuroinflammation and support neuronal survival¹², and large-scale observational studies have consistently associated GLP-1 therapies with a 20–35% lower incidence of dementia in patients compared with other glucose-lowering treatments¹³. However, the EVOKE and EVOKE+ Phase 3 trials, enrolling nearly 3,800 participants with amyloid-confirmed early Alzheimer's disease across 40 countries, found that oral semaglutide did not significantly slow clinical progression compared with placebo^14,15. Yet the biomarker data told a more nuanced story: semaglutide produced significant reductions in phosphorylated tau and neuroinflammation markers, alongside 30% decrease in C-reactive protein¹⁶. These biological signals, combined with a separate Phase 2b trial of liraglutide that demonstrated nearly 50% less brain volume loss over 12 months¹⁷, suggest that GLP-1 receptor agonists may hold greater promise in combination with other therapies or as a preventive intervention earlier in the disease course; a shift now being actively explored across the Alzheimer’s pipeline¹⁸.

Beyond disease modification: a broadening therapeutic landscape

Innovation in Alzheimer's care is not limited to amyloid-targeting therapies, extending beyond slowing clinical progression. In April 2026, the FDA approved Auvelity as the first non-antipsychotic treatment for agitation associated with Alzheimer's disease, a symptom experienced by up to 76% of patients and one of the most burdensome aspects of the disease for families and carers^19,20. The approval is currently limited to the US, raising familiar questions about when and whether UK patients will benefit. As the therapeutic landscape broadens beyond disease modification to include symptomatic treatment and novel mechanisms of action, the need for rigorous real-world evidence frameworks to evaluate these approaches will only grow.

The Evidence Gap: From Innovation to Impact

Despite these advances, significant gaps remain in how Alzheimer's disease is identified, managed, and experienced in routine care. The scale of the challenge is clear, but national figures only tell part of the story. The burden of Alzheimer's disease is not shared equally. A 2024 review by the Office of Health Economics, commissioned by the Alzheimer's Society, uncovered 110 inequalities experienced by people living with dementia and their carers across England, Wales and Northern Ireland, ranging from disparities in diagnosis and prescribing to variations linked to geography, deprivation, age and ethnicity²¹. For people from ethnic minority backgrounds, the barriers are compounded: in some communities, dementia is not explicitly recognised as a medical concept, cultural attitudes towards caregiving can discourage families from seeking formal support, and many diagnostic services remain poorly adapted to the populations they serve. Meanwhile, the Care Quality Commission’s 2025 review of dementia care in England found that health and social care staff do not consistently recognise the individual care needs of people living with dementia, and that care settings can fall short in supporting their day-to-day wellbeing²².

Capturing this complexity demands more than traditional research methods. Clinical trials can show whether an intervention works under controlled conditions; real-world data shows who reaches diagnosis, who receives care, who is left behind, and whether benefit is realised across everyday NHS pathways. Randomised controlled trials, while the gold standard for establishing safety and efficacy, are not designed to reflect the variation across populations, long-term care pathways, or the socioeconomic factors that shape real-world outcomes. As IQVIA has previously highlighted, progress in neurological diseases is often incremental and complex, and translating scientific advances into patient benefit requires sustained evidence generation across both clinical and real-world settings²³.

These are the questions that real-world evidence is uniquely positioned to answer: which patients benefit most from emerging therapies, and at what stage of disease; how outcomes vary across populations, care settings, and pathways; and why some patient groups remain undiagnosed, untreated, or underserved. Addressing them demands evidence that connects what happens in routine care with the clinical complexity seen in specialist settings.

This is where IQVIA’s broader real world evidence capability becomes critical: connecting clinical, epidemiological, health economic and access questions in a way that supports confident decision-making by regulators, payers, clinicians and health systems^24,25. In Alzheimer’s disease, that means moving beyond whether an innovation works, to understanding who it works for, where it can be delivered, and how its value is realised in routine NHS care.

Real-World Evidence in Action: From Primary Care to Specialist Insight

Understanding Alzheimer’s disease in the real world requires data that spans the full patient journey, from the earliest GP consultation to specialist diagnosis and long-term management. IQVIA brings together complementary data assets that provide a more complete view of dementia care in the UK.

The value of these assets lies not only in the data itself, but in the ability to turn routine NHS information into evidence that supports better clinical decisions, pathway planning and patient outcomes^26,27. For Alzheimer’s disease, that means using data from everyday care to identify missed diagnoses, quantify variation, and support more targeted, equitable intervention.

Primary care insight at speed and scale: IMRD and IQVIA data partner

IQVIA Medical Research Data (IMRD) is a longitudinal primary care dataset capturing millions of non-identified patient electronic health records (EHR) across England. Combined with IQVIA’s data partner, an automated platform for extracting and analysing EHR data, it transforms routine clinical information into actionable insight at speed and scale, reducing complex epidemiological analyses from months to minutes.

The impact of this approach is already evident: more than 150 peer reviewed publications generated through IQVIA’s data partner, with the platform enabling faster, robust, standardised and reproducible analysis from cohort definition, through to data extraction and study execution. Evidence of this approach has also recently been presented at ISPOR²⁸. Critically, IMRD, which is linked to ethnicity and deprivation indicators via IQVIA’s data partner, allows researchers to move beyond population averages and generate insights that reflect how Alzheimer’s disease is experienced across different communities.

Specialist mental health insight: Akrivia Health

Primary care data is only part of the picture. Understanding Alzheimer’s disease across the lifecycle also requires visibility into the specialist secondary care settings where diagnosis, assessment, and management are concentrated. IQVIA’s partnership with Akrivia Health extends that view by combining epidemiological expertise with one of the most in-depth real-world datasets dedicated to mental health and dementia.

Rather than relying only on structured fields and medical codes, Akrivia Health uses artificial intelligence (AI) and natural language processing (NLP) to extract insights from both structured and unstructured clinical records, including clinicians’ narrative notes.  The result is research-ready data that captures aspects of disease progression and patient experience often missed in standard datasets. This includes longitudinal cognitive assessments such as MMSE and MoCA scores, charting how cognition changes over months and years rather than at a single point in time. It also captures early behavioural and functional changes and distinguishes between distinct patient progression trajectories, differentiating rapid decliners from those who remain stable. Together, this level of granularity supports earlier identification of individuals before formal diagnosis, when intervention may offer the greatest benefit.

The real strength of this approach lies in integration. IQVIA can integrate these specialist insights with IMRD and broader assets, enabling validation across datasets and supporting end-to-end evidence generation, from early feasibility and study design through to post-launch evidence development. This combined primary-to-specialist approach ensures that data is not only accessible, but actionable. For Alzheimer's disease, this means a single, connected view of how patients move through the system, where care falls short, and where new therapies could deliver the greatest benefit.

Why This Matters Now: Policy, Pipeline, and the Urgency of Access

Having the right data assets is necessary, but not sufficient. Whether they are used to their full potential depends on the policy environment in which they operate. Alzheimer’s disease sits squarely within the wider life sciences trends IQVIA has highlighted in its “Nine for 2026” series: scientific acceleration, constrained health-system capacity, affordability pressure, and growing expectations that innovation should demonstrate value in the real world. These forces are converging particularly sharply in brain health, where policy, pipeline and pathway readiness are no longer separate questions²⁹.

At a time when scientific progress in Alzheimer's disease is accelerating, the policy environment in England risks moving in the opposite direction. As the Alzheimer's Society's CEO, Michelle Dyson warned in March 2026: "The science is moving fast and globally more people are starting to access these drugs, but the UK is falling behind." With 158 Alzheimer's therapies now in development across 192 active clinical trials, including 36 agents in Phase 3³⁰, the volume of evidence required to support reimbursement, treatment pathways, and equitable access is growing rapidly. Yet the diagnostic infrastructure those therapies depend on in the UK is being deprioritised.

IQVIA has made a similar argument in other high-burden, high-innovation therapy areas: when new interventions have the potential to transform care but also place new demands on services and budgets, real world data infrastructure needs to be designed from the outset, not retrofitted once access pressures have already emerged. The case for registries and structured real-world evidence in obesity offers a useful parallel for Alzheimer’s disease, where systems will need to understand eligibility, capacity, outcomes and equity at scale³¹.

Closing that gap depends on real-world evidence, not as a complement to clinical research, but as the infrastructure on which equitable access is built. It is what enables earlier identification, deeper patient characterisation, and the continuous generation of evidence that regulators, payers, and clinicians all require. The scientific tools to change the trajectory of Alzheimer's disease are emerging, and the real-world data capabilities to ensure those tools reach the right patients, at the right time, already exist. The question is no longer whether real-world evidence can help solve these challenges. It is whether we act on it with sufficient urgency and ensure that Brain Health: Access For All is more than a theme. It must become a commitment.

If you are interested in finding out more about how IQVIA can support your Alzheimer's disease research, please [visit our website].

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