Population Attributable Fraction of Modifiable Risk Factors for Dementia in Turkey

Abstract

Dementia affects approximately 55 million people globally, with modifiable risk factors contributing significantly to its prevalence. While global studies have explored these factors, no research has applied the Lancet Commission’s framework to the Turkish population. This study aims to estimate the population attributable fractions (PAFs) of 14 modifiable dementia risk factors in Turkey, using the updated 2024 Lancet Commission framework. Data from the 2022 Turkey Health Survey, a nationally representative dataset, were used to calculate prevalences. The 14 risk factors were categorized into early life (low education), midlife (e.g., physical inactivity, obesity, depression), and later life (e.g., social isolation, air pollution, untreated vision loss). PAFs were computed using relative risks from meta-analyses and the Lancet Commission report. Principal Component Analysis and communalities were applied to account for intercorrelations between factors. The overall weighted PAF for Turkey was 49.9%, indicating that nearly half of dementia cases could be prevented through targeted interventions. Physical inactivity was the leading midlife factor, while social isolation and low education were the most significant contributors in later and early life stages, respectively. Gender-specific analysis revealed higher PAFs in women (54.2%) compared to men (44.3%), driven by differences in physical inactivity, depression, and social isolation. This study highlights the significant preventable burden of dementia in Turkey and underscores the importance of culturally tailored, gender-sensitive interventions. Addressing modifiable risk factors, particularly physical inactivity and social isolation, is critical to reducing dementia prevalence and informing public health strategies.

Keywords

dementia modifiable risk factors population attributable fraction Turkey prevention

Introduction

Dementia is a growing global health problem and one of the leading causes of disability and dependency among older adults. According to the World Health Organization (WHO), approximately 55 million people worldwide are living with dementia, with nearly 10 million new cases diagnosed each year. This burden represents a significant challenge for healthcare systems and societies. Modifiable risk factors contribute substantially to the prevalence of dementia, and addressing these factors offers critical opportunities for prevention (World Health Organization, 2023).

The Lancet Commission on Dementia Prevention, Intervention, and Care has recently revised and expanded the framework for modifiable dementia risk factors in its 2024 report (Livingston et al., 2024). The Commission identified 14 modifiable risk factors that contribute significantly to the global burden of dementia. These factors span the life course and include low education, hearing loss, hypertension, obesity, smoking, physical inactivity, diabetes, depression, social isolation, excessive alcohol consumption, traumatic brain injury (TBI), and the newly added untreated vision loss and high LDL cholesterol. These updates underscore the need to address modifiable risk factors at appropriate stages of life to reduce the risk of dementia worldwide (Livingston et al., 2020, 2024).

Turkey, with its rapidly aging population and unique sociocultural characteristics, offers a distinctive context for investigating the risk factors associated with dementia. The prevalence of obesity and physical inactivity in Turkey is among the highest in Europe, particularly among older adults and women (World Health Organization, 2022). In contrast, alcohol consumption is significantly lower than in many other countries, reflecting cultural and lifestyle differences (The Global Health Observatory, 2020). These unique patterns make Turkey an important case for studying modifiable risk factors for dementia in middle-income countries.

Despite significant advances in understanding dementia risk factors globally, there have been no studies applying either the previous or the updated Lancet Commission framework to the Turkish population. Several international reviews have estimated the population-attributable fraction of modifiable dementia risk factors in diverse contexts, such as global meta-analyses (Stephan et al., 2024) and national studies in Australia (Ashby-Mitchell et al., 2017). By incorporating the updated 2024 framework, this study provides valuable insights into the cumulative impact of modifiable dementia risk factors. Such research is essential for developing targeted public health strategies and addressing regional disparities in dementia prevention efforts.

This study aims to estimate the population attributable fractions (PAFs) of modifiable dementia risk factors in Turkey. By quantitatively assessing these factors, it seeks to inform targeted interventions and public health strategies to reduce the prevalence of dementia in Turkey.

Method

Study Design and Data Sources

This study used data from the 2022 Turkey Health Survey conducted by the Turkish Statistical Institute (TURKSTAT) (Turkish Statistical Institute, 2023). This survey, the seventh iteration of its kind, is designed to provide nationally representative data on demographic, socioeconomic, and health-related variables across Turkey. The survey design ensures a robust representation of the population in urban and rural areas.

The survey used a stratified two-stage cluster sampling design. The stratification was based on urban and rural classifications. In the first stage, clusters of approximately 100 households were selected using probability proportional to size sampling. In the second stage, a systematic random sampling approach with a random start was used to select households within each selected cluster, following the methodology outlined by TURKSTAT.

Data were collected from 11,170 households, representing a total of 29,761 individuals across all age groups. Of these, 22,742 individuals aged 15 years and older were included in specific analyses requiring adult data. For each risk factor, subsamples were selected based on the relevant life-course stage as defined in the Lancet framework (e.g., low education for those under age 45, midlife factors for ages 45–65, and late-life factors for those over 65). No other exclusions were made. The survey was conducted through face-to-face interviews using a structured questionnaire designed to capture a wide range of health-related behaviors and outcomes. This comprehensive design allows for the estimation of the prevalence of various risk factors and ensures reliable data that are representative of the Turkish population (Turkish Statistical Institute, 2023).

Risk Factors and Relative Risks

Risk factors for dementia were selected based on 2024 The Lancet Commission’s life-course model, which identifies 14 modifiable risk factors (Livingston et al., 2024). These factors were categorized into three life stages:

Early life (before age 45): low education.

Midlife (ages 45–65): hearing loss, high LDL cholesterol, TBI, high blood pressure, excessive alcohol use, smoking, depression, physical inactivity, diabetes and obesity.

Later life (over age 65): social isolation, untreated vision loss and air pollution.

The proportions of individuals with each risk factor were calculated from the 2022 Turkey Health Survey, stratified by the corresponding life stage. Data specific to the Turkish population were used to ensure consistency with the definitions provided in the Lancet Commission report. However, data for TBI and air pollution were not available in the survey. For TBI, the prevalence reported in the Lancet Commission was used (12.1%). Additionally, gender-specific prevalences were taken from a meta-analysis by Frost et al., which reported 16.7% in men and 8.6% in women (Frost et al., 2013). While country-specific data were not available, these sources were selected due to their methodological rigor and wide use in comparative studies. For air pollution, the prevalence was estimated based on 2023 data from Turkey, where PM10 averages were assessed. According to this evaluation, at least 92% of the population in Turkey was exposed to air pollution levels exceeding the WHO air quality standards. This figure was used as a proxy for the prevalence of air pollution exposure in this study Right to Clean Air Platform (2024). Although these external estimates may introduce uncertainty, they were chosen to provide the most accurate and contextually relevant approximations available in the absence of direct survey data.

The relative risks (RRs) and their 95% confidence intervals (CIs) for each risk factor were extracted from the Lancet Commission Report (Livingston et al., 2024). These RRs, assumed to be constant across populations, were directly applied to the Turkish population to estimate the risk contribution of each factor.

The definitions of risk factors, along with their associated life stages, are summarized in Table 1.

Table 1.

Modifiable Dementia Risk Factors and Their Definitions

Life stage	Risk factor	Definition
Early life (below 25 years)	Low education	Not completing 8 years of basic education by the age of 25
Midlife (45–64 years)	Hearing loss	Experiencing difficulty hearing in a quiet environment
	High LDL cholesterol	Having high cholesterol or triglyceride levels
	Depression	Having a diagnosis of depression within the past 12 months
	Traumatic brain injury	Mild or severe brain injury (Frost et al., 2013)
	Physical inactivity	Being inactive during the day or engaging in less than 75 minutes of physical activity per week
	Smoking	Currently using tobacco products (e.g., cigarettes, hand-rolled cigarettes, cigars, pipes, heated tobacco products, hookah, etc.)
	Diabetes	Having a diagnosis of diabetes
	Hypertension	Having a diagnosis of hypertension
	Obesity	Having a body Mass index (BMI) of 30 or higher, calculated based on self-reported weight and height data
	Excessive alcohol consumption	Consuming alcohol on an average of 3 or more days per week in the past year
Later life (65+ years)	Social isolation	Living alone
	Air pollution	Living under poor air quality conditions (Right to Clean Air Platform, 2024)
	Untreated vision loss	Difficulty seeing while reading standard text

Statistical Analysis

To account for potential intercorrelations between risk factors, a Principal Component Analysis (PCA) was performed using tetrachoric correlations. The number of factors to retain was determined using the parallel analysis method, which compares the eigenvalues of the observed data with those from randomly generated datasets. Communalities were derived for each risk factor to quantify the shared variance between factors. For risk factors without direct data in the dataset, such as TBI and air pollution, the average communality value of the other risk factors was used to maintain consistency in the weighting process. The use of average communalities for TBI and air pollution, due to the absence of direct correlation data, may introduce minor imprecision. However, as this applies to only two factors, any impact on the overall weighted estimates is likely negligible and consistent with approaches used in similar studies. These communalities were used to adjust individual PAFs, and the weights for each factor were calculated as follows:

W e i g h t = 1 - c o m m u n a l i t y

PAFs for individual risk factors were calculated using the standard formula (Levin, 1953):

P A F = P . \frac{R R - 1}{1 + P . (R R - 1)}

where P represents the proportion of individuals exposed to the risk factor, and RR is the relative risk associated with that factor. Both PAFs and their 95% CIs were estimated using Monte Carlo simulations with 10,000 iterations. For each iteration, relative risks and prevalence values were sampled from their respective distributions (when available). This simulation approach ensures robust estimates by propagating uncertainties from input parameters to the resulting PAFs. Weighted PAFs were derived for each risk factor to account for intercorrelations between factors:

W e i g h t e d P A F = P A F . w e i g h t

Both weighted PAFs and the overall weighted PAF were calculated. The overall weighted PAF was computed to estimate the cumulative impact of all risk factors:

O v e r a l l W e i g h t e d P A F = 1 - [(1 - w e i g h t 1 * P A F 1) . (1 - w e i g h t 2 * P A F 2) . (1 - w e i g h t 3 * P A F 3) \dots . (1 - w e i g h t 12 * P A F 12)]

Weighted PAFs were estimated to determine the relative contribution of each risk factor to the overall attributable fraction. The calculation for weighted PAF is as follows:

W e i g h t e d P A F = \frac{i n d i v i d u a l w e i g h t e d P A F}{\sum i n d i v i d u a l w e i g h t e d P A F} * o v e r a l l w e i g h t e d P A F

The weighted PAF calculation was refined to account for shared variance among risk factors. By incorporating communalities, the adjusted formula provides a more accurate estimate of each factor’s contribution and their combined impact on dementia risk. All analyses were performed using R software (version 4.0.3), with the psych package utilized for PCA and tetrachoric correlation calculations.

Ethical Considerations

The study used anonymized data obtained from the TURKSTAT upon formal request. Permission for data use was granted by TURKSTAT. Ethical approval was not required for this secondary data analysis, as no identifiable personal information was accessed or processed.

Results

Overall Population Analysis

The PAFs and weighted PAFs for dementia risk factors across the life course are summarized in Table 2 and visualized in Figure 1. The overall weighted PAF for the total population was estimated to be 49.9%, indicating that nearly half of dementia cases in Turkey could potentially be prevented by addressing these modifiable risk factors.

Table 2.

Weighted PAFs for Dementia Risk Factors Across the Life Course

Risk factors	RR (95%CI)	Prevalence % (95% CI)	Communality	PAF % (95% CI)	Weighted PAF % (95%CI)
Early Life (<45)
Less education	1.6 (1.3–2)	25.4 (24.5–26.3)	0.463	14.0 (7.5–20.0)	5.6 (3.0–8.0)
Midlife (45–65)
Hearing loss	1.4 (1–1.9)	9.8 (9.1–10.5)	0.238	4.1 (2.3–7.8)	2.3 (1.3–4.5)
High LDL cholesterol	1.3 (1.3–1.4)	16.1 (15.3–17.0)	0.578	5.3 (4.6–6.2)	1.7 (1.4–1.9)
Depression	2.2 (1.7–3.0)	9.6 (8.9–10.3)	0.426	11.3 (6.6–16.1)	4.9 (2.8–6.9)
Brain injury	1.7 (1.4–1.9)	12.1	0.433	7.8 (4.6–9.8)	3.3 (2.0–4.2)
Psychial inactivity	1.2 (1.2–1.3)	48.2 (47.1–49.3)	0.194	10.7 (8.9–12.6)	6.4 (5.3–7.6)
Smoking	1.3 (1.2–1.4)	34.7 (33.6–35.8)	0.577	9.4 (6.7–12.1)	3.0 (2.1–3.8)
Diabetes	1.7 (1.6–1.8)	19.9 (19.0–20.8)	0.608	12.2 (10.6–13.9)	3.6 (3.1–4.0)
Hypertension	1.2 (1.1–1.4)	24.9 (23.9–25.9)	0.705	5.8 (2.6–8.9)	1.3 (0.6–2.0)
Obesity	1.3 (1.0–1.7)	31.6 (30.5–32.7)	0.254	9.6 (5.8–17.8)	5.3 (3.2–9.9)
Alcohol consumption	1.2 (1.0–1.5)	1.4 (1.1–1.7)	0.641	0.4 (0.2–0.7)	0.1 (0.0–2.0)
Later life (65>)
Social isolation	1.6 (1.3–1.8)	18.7 (17.3–20.1)	0.170	9.2 (5.5–13.0)	5.7 (3.4–8.1)
Air pollution	1.1 (1.1–1.1)	92.0	0.433	8.4 (6.9–10)	3.6 (2.9–4.2)
Untreated vision loss	1.5 (1.4–1.6)	14.2 (13.0–15.4)	0.343	6.6 (5.3–8.1)	3.2 (2.6–4.9)
Overall PAF					49.9

Weighted PAFs account for shared variance between risk factors, using PCA-based communalities. “Communalities” represent the proportion of variance in each risk factor that is shared with other included factors, estimated using PCA.

Low education, the only early life factor considered, had a weighted PAF of 5.6% (95% CI: 3.0–8.0), contributing significantly to the overall risk of dementia. In midlife, physical inactivity was the most significant contributor, with a weighted PAF of 6.4% (95% CI: 5.3–7.6), followed by obesity (5.3%; 95% CI: 3.2–9.6) and depression (4.8%; 95% CI: 2.9–6.9). Among later life factors, social isolation had the largest contribution, with a weighted PAF of 5.7% (95% CI: 3.4–8.1), followed by air pollution (3.6%; 95% CI: 2.9–4.2). These findings highlight modifiable areas with substantial potential for public health interventions tailored to different life stages.

Gender Analysis

The PAFs and weighted PAFs stratified by gender are presented in Table 3 and visualized in Figure 2. The overall weighted PAF was higher for women (54.2%) than for men (44.3%), suggesting a greater preventable burden of dementia in women.

Table 3.

Gender-specific Comparison of Weighted PAFs for Dementia Risk Factors

	Women			Men
Risk factors	Prevalence % (95% CI)	PAF % (95% CI)	Weighted PAF % (95%CI)	Prevalence % (95% CI)	PAF % (95% CI)	Weighted PAF % (95%CI)
Early life (<45)
Less education	30.1 (29.4–32.4)	16.4 (9–23.4)	6.4 (3.5–9.1)	25.4 (24.5–26.3)	14.0 (7.5–20.0)	4.6 (2.4–6.7)
Midlife (45–65)
Hearing loss	10.1 (9.1–11.1)	4.3 (2.0–8.2)	2.3 (0.1–4.5)	9.8 (9.1–10.5)	4.1 (2.3–7.8)	2.3 (0.1–4.6)
High LDL cholesterol	19.4 (18.1–20.7)	6.4 (5.4–7.4)	1.9 (1.6–2.2)	16.1 (15.3–17.0)	5.3 (4.6–6.2)	1.4 (1.1–1.6)
Depression	13.4 (12.3–14.5)	15.1 (8.9–21.2)	6.3 (3.7–8.8)	9.6 (8.9–10.3)	11.3 (6.6–16.1)	3.0 (1.7–4.6)
Brain injury	8.5	5.6 (3.3–7.1)	2.3 (1.4–2.9)	12.1	7.8 (4.6–9.8)	4.6 (2.8–5.8)
Psychial inactivity	55.0 (53.4–56.6)	12.1 (10.0–14.1)	7.0 (5.8–8.2)	48.2 (47.1–49.3)	10.7 (8.9–12.6)	5.8 (4.8–6.9)
Smoking	22.3 (22.0–24.8)	6.2 (4.3–8.2)	1.9 (1.3–2.5)	34.7 (33.6–35.8)	9.4 (6.7–12.1)	4.1 (3.0–5.3)
Diabetes	23.4 (22.0–24.8)	14.0 (12.1–16)	4.0 (3.4–4.5)	19.9 (19.0–20.8)	12.2 (10.6–13.9)	3.1 (2.6–3.6)
Hypertension	30.9 (29.4–32.4)	7.1 (3.2–10.9)	1.5 (0.7–2.3)	24.9 (23.9–25.9)	5.8 (2.6–8.9)	1.0 (0.4–1.6)
Obesity	37.4 (35.8–39.0)	11.1 (7.0–20.4)	6.0 (0.4–11.0)	31.6 (30.5–32.7)	9.6 (5.8–17.8)	4.6 (2.7–8.6)
Alcohol consumption	0.1 (0.0–0.2)	0.0 (0.0–0.1)	0.0 (0.0–0.0)	1.4 (1.1–1.7)	0.4 (0.2–0.7)	0.2 (0.1–0.4)
Later life (65>)
Social isolation	26.4 (24.3–28.5)	12.5 (7.6–17.5)	7.5 (4.5–10.5)	18.7 (17.3–20.1)	9.2 (5.5–13.0)	3.3 (1.8–4.9)
Air pollution	92.0	8.4 (6.9–10)	3.4 (2.8–4.1)	92.0	8.4 (6.9–10)	3.7 (3.0–4.4)
Untreated vision loss	17.1 (15.3–18.9)	7.9 (6.1–9.7)	3.7 (2.9–4.6)	14.2 (13.0–15.4)	6.6 (5.3–8.1)	2.6 (2.0–3.3)
Overall PAF			54.2			44.3

For women, physical inactivity was the most influential midlife factor, with a weighted PAF of 7.0% (95% CI: 5.8–8.2), followed by depression (6.3%; 95% CI: 3.7–8.8). In later life, social isolation was the largest contributor, with a weighted PAF of 7.5% (95% CI: 4.5–10.5).

Among men, physical inactivity also had the largest midlife impact, with a weighted PAF of 6.0% (95% CI: 5.0–7.0), followed by obesity (4.6%; 95% CI: 2.7–8.6). In later life, air pollution emerged as a significant risk factor for men, with a weighted PAF of 3.7% (95% CI: 3.0–4.4). These results emphasize the importance of gender-sensitive strategies in community health planning and dementia prevention policies.

Discussion

This study underscores the substantial preventable burden of dementia in Turkey, with nearly half of dementia cases attributable to modifiable risk factors. Findings from diverse settings such as Latin America, China, the United States, Australia, and other regions highlight the variability in PAFs of dementia risk factors, shaped by cultural, demographic, and socioeconomic contexts (Ashby-Mitchell et al., 2017; Hu et al., 2022; Lee et al., 2022; Mukadam et al., 2019; Paradela et al., 2024). In a recent meta-analysis, the Weighted PAF was found to be 32%, with low education, physical inactivity, hearing loss, hypertension, and obesity showing the highest pooled estimates (Stephan et al., 2024).

In Turkey, physical inactivity emerged as the leading midlife factor, reflecting the country’s distinct lifestyle and health challenges. The prevalence of physical inactivity in Turkey is among the highest in Europe, particularly among women (The Global Health Observatory, 2024). This elevated prevalence is compounded by related factors such as obesity, which also plays a significant role in dementia risk. Both conditions are exacerbated by urbanization, limited access to physical activity opportunities and dietary habits. Although the PAFs for physical inactivity and obesity in this study are higher than those reported in many international studies, they closely align with findings from meta-analyses that emphasize the strong association between these factors and dementia risk (Paradela et al., 2024; Stephan et al., 2024). These results emphasize the critical need for culturally tailored interventions that reduce barriers to physical activity and implement comprehensive strategies to address obesity.

Social isolation, a prominent later-life factor, was another major contributor to dementia risk. Despite strong family traditions, urban migration and changing family dynamics in Turkey have increased the prevalence of isolation among older adults. It is important to note that social isolation in this study was determined based on the question of whether individuals live alone. However, given Turkey’s cultural context, living alone does not necessarily equate to being socially inactive, as individuals may still maintain active social lives through family, neighbors, or community networks. This nuance highlights the need for further research to explore the broader dimensions of social isolation and its impact on dementia. Nonetheless, these findings emphasize the importance of community-based programs and policies that encourage social engagement, particularly in rural areas where older individuals may face greater risks of social disconnection.

Low education, as the primary early-life risk factor, reflects long-standing inequalities in educational access, particularly in rural regions. Policies to improve educational opportunities could have a significant long-term impact on reducing dementia prevalence.

Environmental risks such as air pollution were also notable in this study, with nearly 92% of Turkey’s population living under air quality levels exceeding WHO standards (Right to Clean Air Platform, 2024). This underscores the need for stronger environmental policies to mitigate air pollution and reduce its cognitive health impacts.

In contrast to numerous other countries, Turkey exhibits one of the lowest rates of alcohol consumption worldwide (The Global Health Observatory, 2020). This finding is consistent with the minimal contribution of alcohol consumption to the risk of dementia, as observed in this study.

In addition to the previously recognized factors, new risk factors identified in the 2024 Lancet Commission, such as untreated vision loss and high LDL cholesterol, have been incorporated into the analysis. While these factors contribute less significantly than others, such as physical inactivity or social isolation, their inclusion reflects an evolving understanding of dementia risk. For instance, untreated vision loss highlights the importance of addressing sensory impairments, which can lead to reduced cognitive engagement. Similarly, high LDL cholesterol underscores the role of cardiovascular health in cognitive decline. These findings emphasize the need for multidimensional approaches that address both established and emerging risk factors to effectively mitigate dementia risk.

Gender differences revealed in this study further emphasize the need for targeted interventions. Women had a higher overall weighted PAF than men, primarily due to greater physical inactivity, social isolation, and depression prevalence. These findings align with global trends showing women are disproportionately affected by certain risk factors due to both biological and social determinants (Chen et al., 2024; Paradela et al., 2024; Vergara et al., 2022). For men, factors such as smoking was more prominent contributors, highlighting the importance of addressing these risks in gender-specific prevention strategies. The observed disparities underscore the necessity of designing tailored public health programs that account for gender-specific vulnerabilities.

The observed gender differences in weighted PAFs appear to be driven primarily by the higher prevalence of key risk among women. These differences may not only reflect behavioral and lifestyle patterns but could also stem from broader gender-related social determinants, such as caregiving roles, lower economic participation, and differential access to health-promoting resources. Additionally, potential biological mechanisms, including hormonal changes and differential disease susceptibility, may also play a role. These findings underscore the importance of gender-specific dementia prevention strategies that address both structural and behavioral disparities.

One of the strengths of this study is its use of nationally representative data from the 2022 Turkey Health Survey, which ensures robust and generalizable findings for the Turkish population. Additionally, this study is among the first to apply the updated 2024 Lancet Commission framework, incorporating new risk factors such as untreated vision loss and high LDL cholesterol. The life-course approach further emphasizes the importance of addressing risk factors at appropriate stages of life, from early education to midlife health behaviors and later-life social connections. Statistical techniques, such as PCA and communalities, were employed to account for intercorrelations between risk factors, enhancing the accuracy of weighted PAF estimates. Gender-specific analyses also provide valuable insights into the differential preventable burden of dementia between men and women, supporting tailored public health strategies. Furthermore, by focusing on Turkey, a middle-income country with distinct cultural and demographic features, this study addresses a significant gap in the literature, offering regional insights that can inform global dementia prevention efforts.

However, several limitations should be noted. The reliance on self-reported data may introduce recall and reporting biases. Additionally, the lack of direct prevalence data for traumatic brain injury and air pollution required reliance on external estimates, which may affect the accuracy of these findings. Some risk factors, such as obesity and depression, were associated with relatively wide confidence intervals, possibly due to measurement variability or imbalances in prevalence across age and gender groups. Finally, the study assumes that relative risks are uniform across populations, which may not fully account for genetic, environmental, or sociocultural variations in dementia risk.

Despite these limitations, the findings emphasize the need for comprehensive, culturally sensitive and gender-specific public health interventions to reduce dementia risk in Turkey. Promoting physical activity through community programs, workplace initiatives, and improved urban planning is critical. Enhancing social support for older adults through senior centers and intergenerational programs can address social isolation. Expanding access to quality education, particularly for rural and disadvantaged populations, will increase cognitive reserve and mitigate early-life risks. Strengthening air quality regulations and integrating dementia prevention into chronic disease management programs can further reduce risk. Public education campaigns to raise awareness about modifiable risk factors and regional collaborations to share strategies for dementia prevention are also crucial. By targeting these factors across the life course, significant progress can be made in reducing dementia prevalence and improving public health outcomes in Turkey.

This study demonstrates that nearly half of dementia cases in Turkey could potentially be prevented by addressing modifiable risk factors such as physical inactivity, social isolation, and low education. By applying the updated 2024 Lancet Commission framework, this study provides valuable insights into the unique risk factor profile of Turkey, emphasizing the importance of targeted public health interventions across the life course. These findings highlight the urgent need for culturally and contextually tailored strategies to reduce the dementia burden in Turkey and contribute to global prevention efforts.

Footnotes

ORCID iDs

Bugra Taygun Gulle

Busra Tozduman

Ethical Statement

Since our study was conducted using data from publicly available reports and no human data were used in the analyses, ethical approval was not required.

Author Contributions

Bugra Taygun Gulle: study design, conceptualization, data collection, statistical analysis, preparing the first draft of the manuscript. Busra Tozduman: conceptualization, data collection, critical review of the drafts.

Funding

The authors received no financial support for the research, authorship, and/or publication of this article.

Declaration of Conflicting Interests

The authors declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article

Data Availability Statement

The data that support the findings of this study are available from the corresponding author upon reasonable request.*

Author Biographies

Buğra Taygun Gülle is a public health and epidemiology specialist working at the Izmir Provincial Health Directorate, focusing on community health and migrant health. His areas of expertise include immunization, mental health, non-communicable diseases and their risk factors. He has experience in various research methodologies, including meta-analyses, ecological studies and case-control studies. His work aims to contribute to evidence-based interventions and policies for improving population health.

Buşra Tozduman is a public health specialist and epidemiology fellow working at Dokuz Eylul University, Faculty of Medicine, Departmant of Public Health. She has expertise in health workforce, non-communicable diseases and risk factors, as well as immunization. She has a particular interest in stated preference methods and the econometric analysis of discrete choice data. Additionally, her work includes ongoing research in ecological studies and systematic reviews.

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