Dementia in immigrant groups: A cohort study of all adults 45 years of age and older in Sweden

Prevalence of dementia diagnosis in Sweden by geographical region and sociodemographic subgroups: a nationwide observational study

Background

Although dementia incidence has decreased in high-income countries, it is important to monitor the prevalence of dementia and identify potential underdiagnosis in population subgroups. This study provides the most up-to-date prevalence of dementia diagnosis in Sweden, by geographical regions and sociodemographic groups.

Methods

We identified all individuals aged ≥62 years, registered and alive in Sweden at the end of 2022 (n = 2.48 million). Dementia diagnoses were identified using ICD-9/10 codes in the National Patient Register since 1987, as well as anti-dementia drug use from the Prescribed Drug Register since 2005.

Findings

At the end of 2022, 3.7% (92,293/2,483,798) of people aged ≥62 years in Sweden had a dementia diagnosis from specialist care or drug prescriptions and varied from 0.6% in ages 62-69 to 14.8% in ages ≥90. The prevalence of cognitive impairment diagnosis was 2.5%. There was some geographical variation in the prevalence of dementia diagnosis, with a larger proportion of diagnoses coming from drug prescriptions than from specialist care in northern Sweden. While people born abroad and people without a close relative had a slightly higher prevalence of dementia diagnosis than Swedish born and those with close relatives, the prevalence was substantially lower for people living alone than for cohabiting individuals.

Interpretation

Comparing case estimates from previous screening cohorts, our results suggest underdiagnosis of dementia in the general older population, particularly among people who live alone. In more rural areas with lower availability of memory clinics, primary care may play an important role in diagnosing older adults with dementia.

Funding

Swedish Research Council for Health, Working Life and Welfare; Swedish Research Council; Region Stockholm.

Racial and ethnic minority representation in dementia risk factor research: a scoping review of cohort studies

BACKGROUND

Despite a potentially greater burden of dementia, racial and ethnic minority populations around the world may be more likely to be excluded from research examining risk factors for incident dementia. We aimed to systematically investigate and quantify racial and ethnic minority representation in dementia risk factor research.

METHODS

We performed a two-stage systematic search of databases-MEDLINE (Ovid SP), Embase (Ovid SP) and Scopus-from inception to March 2021 to identify population-based cohort studies looking at risk factors for dementia incidence. We included cohort studies which were population-based and incorporated a clinical dementia diagnosis.

RESULTS

Out of the 97 identified cohort studies, fewer than half (40 studies; 41%) reported the race or ethnicity of participants and just under one-third (29 studies; 30%) reported the inclusion of racial and ethnic minority groups. We found that inadequate reporting frequently prevented assessment of selection bias and only six studies that included racial and ethnic minority participants were at low risk for measurement bias in dementia diagnosis. In cohort studies including a multiethnic cohort, only 182 out of 337 publications incorporated race or ethnicity in data analysis-predominantly (90%) through adjustment for race or ethnicity as a confounder. Only 14 publications (4.2% of all publications reviewed) provided evidence about drivers of any observed inequalities.

CONCLUSIONS

Racial and ethnic minority representation in dementia risk factor research is inadequate. Comparisons of dementia risk between different racial and ethnic groups are likely hampered by significant selection and measurement bias. Moreover, the focus on 'adjusting out' the effect of race and ethnicity as a confounder prevents understanding of underlying drivers of observed inequalities. There is a pressing need to fundamentally change the way race, ethnicity and the inclusion of racial and ethnic minorities are considered in research if health inequalities are to be adequately addressed.

Case Identification and Characterization of Migrants with Dementia in the Lazio Region Using Health Administrative Data

BACKGROUND

A crucial step for planning effective public health policies for migrants with dementia is the collection of data on the local dimensions of the phenomenon and patients' characteristics.

OBJECTIVE

This study aimed to identify and characterize migrants with dementia in the Lazio region using health administrative databases.

METHODS

Residents with dementia aged 50 years or older, living in the Lazio region as of December 31, 2018, were identified using a validated algorithm based on hospital discharge(s), claims for antidementia drugs, and co-payment exemption for dementia. Migrants were defined as people born abroad and grouped in migrants from High Migratory Pressure Countries (HMPCs) and Highly Developed Countries (HDCs). Overall and age-specific prevalence rates were estimated in native- and foreign-born patients.

RESULTS

Dementia was ascertained in 38,460 residents. Among them, 37,280 (96.9%) were born in Italy, 337 (0.9%) were migrants from HDCs, and 843 (2.2%) from HMPCs. Dementia prevalence was higher among natives (1.15%, 95% CI 1.14-1.16) relative to migrants from HDCs (0.60%, 95% CI 0.54-0.67) and HMPCs (0.29%, 95% CI 0.27-0.31). The prevalence of comorbidities did not differ between groups. Migrants with dementia had a lower likelihood of receiving antidementia treatments compared with natives (51.6% in migrants from HDCs, 49.3% in migrants from HMPCs, and 53.5% among Italians).

CONCLUSION

Routinely collected data in healthcare administrative databases can support the identification of migrants with dementia. Migrants exhibited a lower age-standardized prevalence of registered dementia and lower access to dedicated treatments than Italians. These findings are suggestive of underdiagnosis and undertreatment of dementia in migrants.

Behavioural and psychological symptoms of early-onset and late-onset Alzheimer's disease among Chinese adults: analysis of modifiable factors

BACKGROUND

To conduct a comprehensive comparison of behavioural and psychological symptoms of dementia (BPSD) in Chinese people with early-onset Alzheimer's disease (EOAD) and late-onset Alzheimer's disease (LOAD) and analyse the factors of differences.

METHODS

A cross-sectional survey of 93 EOAD and100 LOAD and their caregivers in China from November 2018 to May 2019.

RESULTS

The total Neuropsychiatric Inventory score was significantly higher in LOAD. A higher level of agitation in EOAD was related to a lower quality of life of caregivers and the emotional expression of ignoring people with dementia. Higher euphoria scores in LOAD were associated with reduced negative coping by caregivers and reduced stability and predictability at home.

CONCLUSION

The early identification and management of specific BPSD of EOAD and LOAD by family members and health professionals may improve the quality of care and life for people with dementia and that of caregivers.

“I Know Hyena. Do you Know Hyena?” Challenges in Interpreter-Mediated Dementia Assessment, Focusing on the Role of the Interpreter

Dementia assessment requires functional communication and interaction between healthcare professionals and the patient being assessed. These can be affected by the requirement for an interpreter to communicate with the patient. The purpose of this study was to elucidate the interactions between patient, healthcare professionals and interpreter, focusing on the role of the interpreter and the challenges that may arise in interpreter-mediated dementia assessment. The study had an ethnographic design in which the data consisted of audio and video recordings of 19 dementia assessments conducted in the presence of an interpreter. The data were analyzed using the constant comparative method. The results showed that the interpreter could affect the patient’s performance and results during the dementia assessment. The interpreter could alter the meaning and content of what was communicated, sometimes change information and instructions exchanged between the patient and healthcare professionals, could avoid interpreting everything being said, and occasionally made their own corrections to what was being communicated. This occurred mainly because of the interpreter’s lack of linguistic skills and the interpreter failing to adhere to the ethical guidelines governing their profession. These challenges could also occur when the interpreter was not familiar with the context of dementia assessment. Alterations made by the interpreter to what was being communicated could lead to incorrect evaluation of the patient’s cognitive abilities and health status. This, in turn, may lead to misjudgment of the patient’s remaining resources and symptoms and their required treatment and support.

Modifiable factors associated with behavioural and psychological symptoms of dementia among patients residing at home: The impacts of patient, caregiver and environmental variables

The present study aimed to explore the modifiable factors of behavioural and psychological symptoms of dementia (BPSD) among patients residing at home in terms of patient, caregiver and environmental factors. A cross-sectional survey of 193 patients with dementia residing at home and their caregivers who visited the memory clinic of the Department of Neurology in a tertiary (the highest level) hospital in China from November 2018 to May 2019 was performed. Exacerbated BPSD were associated with patient (old age, high education level, increased dementia severity, and the use of psychotropic drugs), caregiver (low positive aspects and high expressed emotion) and environmental (poor home environment) factors. The use of psychotropic drugs by the patient, positive aspects and expressed emotions of the caregiver, and home environment were modifiable factors that provided evidence for the direction of intervention for BPSD among patients residing at home.

Ethnic and Immigrant Variations in the Time Trends of Dementia and Parkinsonism

OBJECTIVE

We assessed long-term incidence and prevalence trends of dementia and parkinsonism across major ethnic and immigrant groups in Ontario.

METHODS

Linking administrative databases, we established two cohorts (dementia 2001-2014 and parkinsonism 2001-2015) of all residents aged 20 to 100 years with incident diagnosis of dementia (N = 387,937) or parkinsonism (N = 59,617). We calculated age- and sex-standardized incidence and prevalence of dementia and parkinsonism by immigrant status and ethnic groups (Chinese, South Asian, and the General Population). We assessed incidence and prevalence trends using Poisson regression and Cochran-Armitage trend tests.

RESULTS

Across selected ethnic groups, dementia incidence and prevalence were higher in long-term residents than recent or longer-term immigrants from 2001 to 2014. During this period, age- and sex-standardized incidence of dementia in Chinese, South Asian, and the General Population increased, respectively, among longer-term immigrants (by 41%, 58%, and 42%) and long-term residents (28%, 7%, and 4%), and to a lesser degree among recent immigrants. The small number of cases precluded us from assessing parkinsonism incidence trends. For Chinese, South Asian, and the General Population, respectively, prevalence of dementia and parkinsonism modestly increased over time among recent immigrants but significantly increased among longer-term immigrants (dementia: 134%, 217%, and 117%; parkinsonism: 55%, 54%, and 43%) and long-term residents (dementia: 97%, 132%, and 71%; parkinsonism: 18%, 30%, and 29%). Adjustment for pre-existing conditions did not appear to explain incidence trends, except for stroke and coronary artery disease as potential drivers of dementia incidence.

CONCLUSION

Recent immigrants across major ethnic groups in Ontario had considerably lower rates of dementia and parkinsonism than long-term residents, but this difference diminished with longer-term immigrants.

The association between sociodemographic characteristics and dementia in patients with atrial fibrillation

Objectives

Association between socio-demographic factors and dementia risk is studied in general but not for atrial fibrillation (AF) patients.

Methods

We studied AF patients ≥ 45 years in Sweden 1998–2012 (n = 537,513) using the Total Population Register for socio-demographic factors, the Swedish Cause of Death Register, and the National Patient Register (NPR) for incident dementia. Cox regression with hazard ratios (HR) and 95% confidence intervals (CI) was used for the association between exposure and outcome, adjusting for age and comorbidities.

Results

Totally 30,332 patients (5.6%) were diagnosed with dementia during the follow-up (mean 5.4 years). Of these, 14,097 were men (4.9%) and 16,235 were women (6.5%). Lower educational levels (reference: highest level) were associated with increased dementia, HRs (95% CI) for basic school for men 1.23 (1.18–1.29) and women 1.36 (1.30–1.42), and middle-level school for men 1.17 (1.11–1.22) and women 1.28 (1.22–1.34). Divorced men and women (reference: married) showed increased risk of dementia, HR 1.07 (1.01–1.13) and 1.12 (1.06–1.18), respectively, while widowed men showed lower risk, HR 0.84 (0.80–0.88). High deprivation neighborhood socio-economic status (NSES; reference: medium level) was associated with increased dementia in men, HR 1.11 (1.05–1.17), and low deprivation neighborhood socio-economic status (NSES) with increased dementia in men and women, HR 1.12 (1.06–1.18) and 1.18 (1.12–1.24), respectively.

Conclusions

Some results were expected, i.e. association between lower educational level and dementia. The higher risk of dementia in low deprivation NSES-areas could be due to a higher awareness about dementia, and subsequent earlier diagnosis and treatment of dementia.

Electronic supplementary material

The online version of this article (10.1007/s40520-019-01449-3) contains supplementary material, which is available to authorized users.

Parkinson's Disease Among Immigrant Groups and Swedish-Born Individuals: A Cohort Study of All Adults 50 Years of Age and Older in Sweden

BACKGROUND

There is a lack of studies of Parkinson's disease (PD) in immigrants.

OBJECTIVE

To study the association between country of birth and incident PD in immigrants in Sweden versus Swedish-born individuals.

METHODS

Study population included all adults aged 50 years and older in Sweden (n = 2775736). PD was defined as having at least one registered diagnosis of PD in the National Patient Register. The incidence of PD in different first-generation immigrant groups versus Swedish-born individuals was assessed by Cox regression, expressed as hazard ratios (HRs) and 95% confidence intervals (CI). The models were stratified by sex and adjusted for age, geographical residence in Sweden, educational level, marital status, neighbourhood socioeconomic status and co-morbidity.

RESULTS

Totally 35833 individuals had an incident diagnosis of PD (20401 men and 15432 women). Incidence rates per 100,000 person-years were for all Swedish-born 95.9 and for all foreign-born 60.1; for all men 112.3 and for all women 73.4, with a male to female ratio of 1.53, with the highest incidence rates for the group 80-84 years of age. After adjusting for potential confounders, the overall relative risk of PD was lower in immigrant men (HR 0.78; 95% CI 0.74-0.82) and women (HR 0.92; 95% CI 0.87-0.98). Among immigrant subgroups, a higher risk of PD was found among women from Finland (HR 1.13; 95% CI 1.05-1.23).

CONCLUSION

In general, the risk of PD was lower in first-generation immigrant men and women compared to Swedish-born. The only group with a higher risk of PD was women from Finland.

High incidence of dementia in Faroese-born female residents in Denmark

INTRODUCTION

To assess whether the incidence of dementia among immigrants in Denmark from the Faroe Islands is similar to that of the inhabitants of their new country.

METHODS

Data on Faroese-born immigrants in Denmark were retrieved from the Danish Central Population Register. Incident dementia cases were identified from the Danish National Patient Register. Standardized incidence ratios (SIRs) were used to compare the dementia incidence in immigrants with the general Danish population.

RESULTS

Female, first-generation Faroese immigrants had double the risk of dementia compared with Danes (SIR 2.1, 95% confidence interval [CI] 1.8-2.5); the excess risk prevailed even beyond 10 years in Denmark, and it affected all sub-types of dementia. In male immigrants, only a modest, statistically non-significant excess risk was seen (SIR 1.2, 95% CI 0.9-1.6).

DISCUSSION

The observation of an excess risk of dementia in women only but not in men of Faroese origin living in Denmark underscores the complexity of the etiology of dementia.

The Association Between Cancer and Dementia: A National Cohort Study in Sweden

Background: Previous studies have found that the incidence of dementia is lower in patients with cancer. However, the impact of survival bias, as well as the confounding by medical treatment, have not been fully addressed. We aimed to explore the subsequent risk of dementia in different follow-up intervals among patients with cancer, as well as the risk before the diagnosis of cancer. Methods: By using the Swedish Cancer Register and the Swedish Hospital Discharge Register, we systematically examined the risk of dementia among patients diagnosed with 35 different types of cancer. Standardized incidence ratios (SIRs) were used to calculate the relative risk. Results: The subsequent risk of dementia in patients with cancer decreased by 21% compared to matched cancer-free controls (SIR = 0.79, 95% CI 0.78-0.80). For specific cancer sites, 21 of them had a significantly lower risk of subsequent dementia. The decreased risk of dementia was also significant before the diagnosis of cancer. However, the risk was higher among patients with cancer who survived for more than 10 years' post-diagnosis (SIR = 1.37, 95% CI 1.32-1.41). Conclusions: In this population-based study, we found that the risk of dementia was lower among patients with cancer, and the risk was also lower before the diagnosis of cancer. This suggests that lower dementia risk is not simply due to bias. However, the underlying mechanisms need to be explored further.