Dementia is a degenerative disease that commonly prevails within the older population. About 1.3% of the UK’s population has been diagnosed with dementia.

More specifically, one in 14 people above 65 years of age within the U.K. has dementia, the incidence of which increases to at least one in six amongst people who find themselves over 80 years of age. Since people over 65 years of age are the fastest-growing age group within the U.K., the variety of dementia cases will likely rise in the approaching years.

Study: Latest cases of dementia are rising in elderly populations in Wales, UK. Image Credit: Naeblys / Shutterstock.com

Background

Western Europe has presented mixed data regarding dementia diagnoses. For instance, a reduced incidence of dementia was reported in Sweden and Germany, whereas a rise in latest dementia cases has been reported in Denmark.

It can be crucial to accurately estimate the prevalence of dementia in homogenous populations, because it is difficult to estimate the true incidence in a broader population.

Alzheimer’s disease (AD) is essentially the most common type of dementia, followed by vascular dementia (VD). Some individuals present with multiple dementia subtypes, which might be because of the overlap within the diagnosis criteria. Usually, people experience two dementia disorders, corresponding to AD and Parkinson’s disease (PD), concurrently.

Concerning the study

A recent Journal of the Neurological Sciences study determined how the incidence and prevalence of dementia have modified over recent many years in Wales. The overlap between diagnoses of dementia subtypes was also investigated.

Data on the Welsh population was obtained from the Secure Anonymized Information Linkage (SAIL) databank, which provides a health-related dataset using anonymized IDs.

Details about dementia diagnoses was obtained from databases of hospital admission records using the International Classification of Diseases tenth Revision (ICD10) and National Health Service (NHS) read codes. Moreover, demographic data were collected from demographic databases.

The present study utilized data on dementia between January 1, 1999, and December 31, 2018. The Welsh Index of Multiple Deprivation (WIMD) was used to find out geographical areas with the best and least deprivation across multiple domains, including employment, education, income, housing, access to services, community safety, and health.

Study findings

All dementia cases were extracted from databases and categorized following specific dementia subtypes, including AD, frontotemporal dementia (FTD), Huntington’s disease (HD), Lewy bodies (DLB), VD, and PD.

For all individuals, the primary instance of every diagnosis was considered. Individuals diagnosed with “drug-induced” or “alcohol-induced” dementia weren’t considered on this study. Finally, a complete of 206,640 ‘unique’ diagnoses were found.

Throughout the study period, the next incidence of AD and VD was observed within the Welsh population. As well as, a big percentage of non-specific dementia diagnoses prevailed, followed by DLB, FTD, and HD. A rise within the incidence and prevalence rates of overall dementia occurred between 1999 and 2018.

The incidence rates of dementia augmented in older people above 70 years of age and decreased in those younger than 60 years of age. Nonetheless, a big decrease within the prevalence of dementia occurred in individuals under 40 years of age, whereas the prevalence of dementia increased in those above 50 years of age. 

Although no significant difference within the incidence and prevalence of overall dementia was observed between women and men, the next variety of females living with dementia was reported.

Substantial overlap was found between dementia subtypes, particularly AD and VD, was observed, thus indicating the potential for initial misdiagnosis favoring more common subtypes.

Assuming a linear increase in dementia incidence until 2050, the all-cause dementia incidence rate was estimated to be 6.5 for each 1,000 people in the whole population. This study also predicted the incidence rate to be 23.2 for each 1,000 people over 65 years of age. Nonetheless, there’s a possibility of the oldest age groups plateauing, which could stabilize the incidence rates.

Conclusions

Certainly one of the critical limitations of the study is the datasets used ranged over twenty years, during which the standards for the diagnosis of dementia has modified. As well as, the mortality coding practice within the U.K. modified in 2011, which led to changes within the reported explanation for death. Because of this of those changes, it is feasible that many dementia cases were ignored on this study. 

Despite these limitations, medical records of the Welsh population indicate a rise in latest dementia diagnoses in older people between 1999 and 2018. This remark is linked with aging and prolonged survival time after diagnosis.

Because the elderly population within the U.K. rises, it will be important to predict how dementia incidence and prevalence will proceed in the longer term.