Title: Dementia undetected or undiagnosed in primary care: the prevalence, causes and consequences
Funder: Department of Health and Social Care

Abstract: Background Between 600,000 and 800,000 people in England have dementia, yet only around 344,000 are recorded on dementia registers maintained by GPs. So a substantial proportion of people with dementia do not have a diagnosis. Closing this diagnosis gap is an NHS and Department of Health priority, but very little is known about the population with undiagnosed dementia, and there is little direct evidence regarding the benefits of a dementia diagnosis. Aims We will link data from an existing longitudinal cohort study (Medical Research Council Cognitive Function and Ageing Study; CFAS II) with primary care records to estimate the prevalence of undiagnosed dementia and its distribution among the older population of England, the barriers to diagnosis and the clinical and psychosocial impacts of diagnosis among people with dementia. Methods and research questions Around 460 participants of CFAS II received a study diagnosis of dementia between 2008 and 2012 and gave consent for their medical records to be examined. CFAS II is designed such that these participants are representative of the English population aged 65 and older with dementia. We will contact their GPs to ascertain whether dementia was suspected, diagnosed or recorded on dementia registers at the time of study diagnosis. CFAS II assessments include: • A comprehensive cognitive assessment • Informant reports of psychiatric and medical comorbidity (including history and treatment) and functional impairment • Behavioural and psychological assessment • Social participation and contacts • GMS/AGECAT dementia diagnosis: a widely used algorithmic dementia diagnosis, validated against Diagnostic and Statistical Manual (DSM) definitions and upon which many UK and global dementia prevalence estimates are currently based. From GP records we will extract and link: • Fact and date of dementia diagnosis and presence on QOF dementia registers • First mention of memory/cognitive impairment • Referrals to dementia services • Censoring events By combining these data we will answer the following questions: Primary objectives: • What was the prevalence of undiagnosed dementia between 2008 and 2012? • What are the associations between social and clinical characteristics of a person with dementia and their risk of being undiagnosed? • To what extent does the dementia register mandated by the quality outcomes framework (QOF) reflect GPs knowledge of cognitive impairment among their patients? Secondary objectives: • How are clinical and psychosocial trajectories over a two year follow-up period associated with diagnosis status among people with dementia? Dissemination and Impacts Our dissemination plan is designed to reach all relevant stakeholders to inform the policy debate around dementia diagnosis and the design and implementation of plans to achieve timely diagnosis of dementia for all. Timetable This work is expected to take 24 months. Months 1-5: Develop and pilot a data collection protocol, refine analysis objectives. Months 6-12: Data collection phase. Months 13-24: Data linkage, quality assurance, analysis, dissemination activities.

Lay abstract: Background to our research About 700,000 people in England have dementia. Dementia causes a gradual loss of memory and other brain functions including language and decision making. People with dementia can cope well in its early stages and continue their normal life, but as dementia progresses they need more help with everyday tasks, and can lose their independence and the things they enjoy. Dementia can affect mood and lead to challenging behaviour and places a large strain on caregivers and relationships. What is the gap in knowledge that we will address? GPs in England reported 344,000 cases of dementia in 2013-2014, which provides a rough indication that about half of all people with dementia are not diagnosed. There are potential benefits and harms of receiving a dementia diagnosis. It is accepted that people with dementia should be diagnosed at the best time for them, and a lot of resources are going into trying to improve the diagnosis rate. However, beyond a rough estimate of their number we do not know enough about people with undiagnosed dementia. We don’t know whether more live alone, with family or in care homes, how severe their dementia is relative to others, what symptoms they experience, what level of disability and care needs they have. We don’t know how many have made contact with their doctor and are waiting for a diagnosis or how many have not sought help. Our project will address these questions by identifying a group of people with dementia but without a formal diagnosis and comparing them to a group who are diagnosed. What will we do? We will use data from a group of people found to have dementia as part of another ongoing study. The Medical Research Council Cognitive Function and Ageing Study 2 (CFAS II) selected 7500 people at random from urban and rural parts of England to have a dementia assessment. About 460 people were discovered to have dementia and gave us permission to look at their GP records. We will look at the GP records for this group to see, at the time when CFAS II found them to have dementia, which participants had a dementia diagnosis recorded by their GP and which did not, and if not whether the GP had noted any memory problems or a referral to a memory service. From this we will estimate how many people with dementia in England have not sought help, and how many have been in contact with their GP about their memory problems but are not diagnosed. We will describe the needs of the group with undiagnosed dementia and identify groups that are more likely to be undiagnosed. We will explore the benefits and harms of being diagnosed on health care use, mood, social participation and disability. Why is this study needed now? This is a unique opportunity to study undiagnosed dementia. We have the expertise required and our team is involved with shaping NHS policy on dementia diagnosis. We will present our findings to the general public, to healthcare professionals, policy makers and those in local and national government who are responsible for improving access to diagnostic services.

Research activity codes: 7.1 INDIVIDUAL CARE NEEDS;8.1 ORGANISATION AND DELIVERY OF SERVICES
Health categories: NEUROLOGICAL