Interpretation of dementia diagnosis and treatment trends in the UK over time
Authors: Carol Brayne
Journal: The Lancet Public Health (2017)

The study by Katherine Donegan and colleagues,1Donegan C Fox N Black N Livingston G Banerjee S Burns A Trends in diagnosis and treatment for people with dementia in the UK from 2005 to 2015: a longitudinal retrospective cohort study.Lancet Public Health. 2017; (published online Feb 23.)http://dx.doi.org/10.1016/S2468-2667(17)30031-2Summary Full Text Full Text PDF PubMed Scopus (84) Google Scholar published in The Lancet Public Health, provides a powerful analysis of routine data for dementia diagnosis rates and prescription practices over a period during which policies and practices have changed in the UK. The analysis presented in this Article uses the presence of codes in routine datasets indicating a dementia diagnosis during a 10 year period from 2005 to 2015. These data were extracted and examined in relation to prescribing practices and then linked to policy developments in the UK during this time. The policies relate to closing the estimated gap in dementia diagnosis and the emerging evidence of adverse outcomes in people with dementia who are prescribed antipsychotic medication. Increased recorded dementia diagnosis rates and reduced antipsychotic medication prescription were observed during this period in the present study. The rise in recorded diagnosis is moving closer at a national level to reaching the levels of prevalence from current estimation of dementia in the population from epidemiological studies. Background factors should be taken into consideration when interpretating the meaning of such changes. The UK has a substantial set of primary care providers whose electronic data are available over several decades. These data can be related to the underlying geographical population estimates because of the nature of the country's comprehensive National Health Service (NHS) and the historically place-based nature of its primary care provision. The Clinical Practice Research Datalink (CPRD), used in this study, is available to approved researchers wishing to test specific hypotheses. Necessarily, the data are limited to what is coded and available, with interpretation required about how the coded data relate to an underlying truth. The data include dementia-related diagnoses communicated between primary care and secondary care and the analysis by Donegan and colleagues assumes the diagnoses in primary care reflect an accurate diagnosis and that prescribing data also reflect what medications people take on a regular basis. This study is an important contribution to our understanding of time trends in diagnostic practice and prescribing despite these caveats, which affect interpretation. The study links observed routine record changes to the UK's and its devolved nations' policy initiatives2Department of HealthLiving well with dementia: a national dementia strategy.https://www.gov.uk/government/uploads/system/uploads/attachment_data/file/168220/dh_094051.pdfGoogle Scholar, 3Department of HealthPrime Minister's challenge on dementia—delivering major improvements in dementia care and research by 2015.https://www.gov.uk/government/uploads/system/uploads/attachment_data/file/215101/dh_133176.pdfGoogle Scholar during the same period. These included ageing and specific dementia-related policy documents aiming to create more compassionate and effective approaches for an ageing population, including those with dementia, within the NHS. Raising awareness of dementia in the population and its importance to society, including costs, was also part of this drive. These activities, closely linked to attention from many sections of the society including media and media personalities, all political parties, charities, researchers, pharmaceutical companies and other business sectors, and health and social care sectors, have resulted in the fact that dementia is now rarely out of the headlines. The media activities included hard hitting campaigns (and some would argue the language and imagery used could reinforce stigma although evidence either way is limited4Swaffer K Dementia: stigma, language and dementia-friendly.Dementia. 2014; 13: 709-716Crossref PubMed Scopus (119) Google Scholar), with a substantial emphasis on seeking help at an early or timely stage if an individual or their loved ones were concerned about a person's memory or related behaviours. Beyond these media campaigns, there has been a top-down drive for general practitioners to seek out dementia diagnoses, with use of a carrot5Hope J What a surprise! Scheme to pay family doctors £55 for every dementia patient on their books sees diagnoses rise by a quarter.http://www.dailymail.co.uk/health/article-3043810/What-surprise-Scheme-pay-family-doctors-55-dementia-patient-books-sees-diagnoses-rise-quarter.htmlGoogle Scholar, 6Price C GPs to be paid £150 to diagnose and treat dementia.http://www.pulsetoday.co.uk/clinical/more-clinical-areas/neurology/gps-to-be-paid-150-to-diagnose-and-treat-dementia/20033565.articleGoogle Scholar and stick approach with money in some localities for diagnosis and, across England, a heavy central diktat to primary care bringing in targets originally based on estimates of prevalence derived from 20 year old epidemiological studies of dementia in the UK, now updated using contemporary estimates (Cognitive Function and Ageing Studies in England and Wales7MRC CFAS Cognitive function and dementia in six areas of England and Wales: the distribution of MMSE and prevalence of GMS organicity level in the MRC CFA Study.Psychol Med. 1998; 28: 319-335Crossref PubMed Scopus (225) Google Scholar, 8Matthews FE Arthur A Barnes LE et al.A two-decade comparison of prevalence of dementia in individuals aged 65 years and older from three geographical areas of England: results of the Cognitive Function and Ageing Study I and II.Lancet. 2013; 382: 1405-1412Summary Full Text Full Text PDF PubMed Scopus (705) Google Scholar, 9NHS EnglandNHS England is set to target "shockingly low" diagnosis rates of dementia in England in a move that could see tens of thousands of people identified and treated each year.https://www.england.nhs.uk/2013/05/Dementia-targets/2013Google Scholar) as well as introducing screening for dementia for some admissions in hospital settings. Such carrot and stick approaches have not been universally welcomed, but they are likely to have substantially affected practice during this period. Part of these policy drives included specific actions resulting from evidence about the harms of antipsychotic prescribing to people with dementia leading to dedicated streams of efforts from centre to periphery to vigorously pursue reduction of such prescribing, particularly in care settings, through the structures of the NHS. The description of the recorded changes in practice is the strength of this study1Donegan C Fox N Black N Livingston G Banerjee S Burns A Trends in diagnosis and treatment for people with dementia in the UK from 2005 to 2015: a longitudinal retrospective cohort study.Lancet Public Health. 2017; (published online Feb 23.)http://dx.doi.org/10.1016/S2468-2667(17)30031-2Summary Full Text Full Text PDF PubMed Scopus (84) Google Scholar and represents a major contribution. Whether there is a societal benefit from such policies and changed practice is less easy to assess. This requires a different type of analysis and a different type of evidence. Many would argue that the specific policies relating to targets and prescribing should have been underpinned by at least some implementation science to estimate evidence of size of benefit, potential harms, costs, and opportunity costs before a heavy handed system roll out. At the local level, the pressures for physicians, the health-care sector, and systems to behave in particular ways will have cost (with consequent opportunity costs at all levels) a great deal in specialist and NHS system professional time and resources throughout the health-care sector at a time of major reorganisation and austerity. There is also a concern that the reduction in prescription of antipsychotics has been accompanied by increases in the prescription of other, potentially harmful, medications because the underlying reason for the prescription in the first place has not been addressed, and cannot be, within current resourcing. Evidence on this concern has produced mixed findings.10Guthrie B Clark SA Reynish EL McCowan C Morales DR Differential impact of two risk communications on antipsychotic prescribing to people with dementia in scotland: segmented regression time series analysis 2001–2011.PLoS One. 2013; (published online July 17.)https://doi.org/10.1371/journal.pone.0068976Crossref Scopus (34) Google Scholar, 11Gallini A Andrieu S Donohue JM Oumouhou N Lapeyre-Mestre Gardette V Trends in use of antipsychotics in elderly patients with dementia: Impact of national safety warnings.Eur Neuropsychopharmacol. 2014; 24: 95-104Summary Full Text Full Text PDF PubMed Scopus (66) Google Scholar, 12Norgaard A Jensen-Dahm C Gasse C Hansen HV Waldemar G Time trends in antipsychotic drug use in patients with dementia: a nationwide study.J Alzheimer's Dis. 2016; 49: 211-220Crossref PubMed Scopus (29) Google Scholar Holistic evidenced compassionate approaches with highly trained staff are alternative methods but not affordable or available to substantial proportions of people with dementia. Future policy implementation should be preceded by a full exploration of the possible unintended consequences and their implications, through service testing methods (such as pilots in more usual sites, staggered roll out, rigorous publishable evaluation of natural experiments, no innovation without evaluation, modelling using various types of datasets, and simulation with different assumptions) wherever possible. Donegan and colleagues1Donegan C Fox N Black N Livingston G Banerjee S Burns A Trends in diagnosis and treatment for people with dementia in the UK from 2005 to 2015: a longitudinal retrospective cohort study.Lancet Public Health. 2017; (published online Feb 23.)http://dx.doi.org/10.1016/S2468-2667(17)30031-2Summary Full Text Full Text PDF PubMed Scopus (84) Google Scholar have done an excellent analysis and their cautious attempt to link these changes with the timing of specific policy initiatives is not entirely without a prior sense of assumed benefit. The clear message of this study is strong evidence that it is possible to examine practice changes across time and relate them in a non-causal manner to societal changes. This is undoubtedly a valuable exercise, but we too must be extremely cautious in interpretation. CB declares no competing interests. Trends in diagnosis and treatment for people with dementia in the UK from 2005 to 2015: a longitudinal retrospective cohort studyOver the 10 years studied, there is evidence of a sustained positive change in diagnosis rates of dementia and in the quality of drug treatment provided to those diagnosed. The prescription of antidementia drugs more than doubled and the prescription of potentially hazardous antipsychotics halved after the introduction of national dementia strategies. These data support the formulation and delivery of national policy to improve the quality of care for people with dementia. Full-Text PDF Open Access