Diabetes increases the risk of depression: A systematic review, meta-analysis and estimates of population attributable fractions based on prospective studies

We aim to examine the relationship between diabetes and depression risk in longitudinal cohort studies and by how much the incidence of depression in a population would be reduced if diabetes was reduced. Medline/PubMed, EMBASE, PsycINFO, and Cochrane Library databases were searched for English-language published literature from January 1990 to December 2017. Longitudinal studies with criteria for depression and self-report doctors' diagnoses or diagnostic blood test measurement of diabetes were assessed. Systematic review with meta-analysis synthesized the results. Study quality, heterogeneity, and publication bias were examined. Pooled odds ratios were calculated using random effects models. Population attributable fractions (PAFs) were used to estimate potential preventive impact. Twenty high-quality articles met inclusion criteria and were analyzed. The pooled odds ratio (OR) between diabetes and depression was 1.33 (95% CI, 1.18-1.51). For the various study types the ORs were as follows: prospective studies (OR 1.34, 95% CI 1.14-1.57); retrospective studies (OR 1.30, 95% CI 1.05-1.62); self-reported diagnosis of diabetes (OR 1.37, 95% CI 1.17-1.60); and diagnostic diabetes blood test (OR 1.25, 95% CI 1.04-1.52). PAFs suggest that over 9.5 million of global depression cases are potentially attributable to diabetes. A 10-25% reduction in diabetes could potentially prevent 930,000 to 2.34 million depression cases worldwide. Our systematic review provides fairly robust evidence to support the hypothesis that diabetes is an independent risk factor for depression while also acknowledging the impact of risk factor reduction, study design and diagnostic measurement of exposure which may inform preventive interventions.

Trends in percentages of gestational diabetes mellitus attributable to overweight, obesity, and morbid obesity in regional Victoria: an eight-year population-based panel study

BACKGROUND

Gestational diabetes mellitus (GDM) is the fastest growing type of diabetes in Australia with rates trebling over the past decades partially explained by rising obesity rates and maternal age among childbearing women. Percentage of GDM attributable to obesity has been documented, mostly focusing on metropolitan populations. In parts of regional (areas outside capital cities) and rural Australia where overweight, obesity and morbid obesity are more prevalent, intertwined with socioeconomic disadvantage and higher migrant communities, trends over time in adjusted percentages of GDM attributed to obesity are unknown.

METHODS

In this population-based retrospective panel study, women, without pre-existing diabetes, delivering singletons between 2010 and 2017 in a tertiary regional hospital that serves 26% of Victoria's 6.5 million Australian population were eligible for inclusion. Secular trends in GDM by body mass index (BMI) and age were evaluated. The percentage of GDM that would have been prevented each year with the elimination of overweight or obesity was estimated using risk-adjusted regression-based population attributable fractions (AFp). Trends in the AFp over time were tested using the augmented Dickey-Fuller test.

RESULTS

Overall 7348 women, contributing to 10,028 births were included. The age of expecting mothers, their BMI, proportion of women born overseas, and GDM incidence significantly rose over time with GDM rising from 3.5% in 2010 to 13.7% in 2017, p <  0.001, increasing in all BMI categories. The incidence was consistently highest among women with obesity (13.8%) and morbid obesity (21.6%). However, the highest relative increase was among women with BMI < 25 kg/m2, rising from 1.4% in 2010 to 7.0% in 2017. Adjusting for age, country of birth, socioeconomic status, comorbidities, antenatal and intrapartum factors, an estimated 8.6% (confidence interval (CI) 6.1-11.0%), 15.6% (95% CI 12.2-19.0%), and 19.5% (95% CI 15.3-23.6%) of GDM would have been prevented by eliminating maternal overweight, obesity, and morbid obesity, respectively. However, despite the rise in obesity over time, percentages of GDM attributable to overweight, obesity, and morbid obesity significantly dropped over time. Scenario analyses supported these findings.

CONCLUSIONS

Besides increasing prevalence of obesity over time, this study suggests that GDM risk factors, other than obesity, are also increasing over time.

Worldwide burden of gastric cancer in 2010 attributable to high sodium intake in 1990 and predicted attributable burden for 2030 based on exposures in 2010

Assessing the impact that patterns of Na intake may have on gastric cancer will provide a more comprehensive estimation of Na reduction as a primary prevention approach. We aimed to estimate the proportion of gastric cancer cases that are attributable to Na intake above the recommendation by the WHO (≤2 g/d) throughout the world in 2010, as well as expected values for 2030. Population attributable fractions (PAF) were computed for 187 countries, using Na intakes in 1990 and 2010 and estimates of the association between Na intake and gastric cancer, assuming a time lag of 20 years. Median PAF ranged from 10·1% in low to 22·5 % in very high Human Development Index (HDI) countries in men (P<0·001) and from 7·2 to 16·6 %, respectively, among women (P<0·001). An increase in median PAF until 2030 is expected in most settings, except for countries classified as low HDI, in both sexes. High Na intakes account for a large proportion of gastric cancer cases, and proportions are expected to increase in almost all of the countries. Intensified efforts to diminish Na intake in virtually all populations are needed to further reduce gastric cancer burden.

Population attributable fraction of lung cancer due to genetic variants, modifiable risk factors, and their interactions: a nationwide prospective cohort study

BACKGROUND

Genetic variants and modifiable risk factors (including environmental exposure and lifestyle) greatly contribute to the development of lung cancer. The population attributable fraction (PAF) of these risk factors, especially their interactive effects, has not been well quantified.

METHODS

A total of 398,577 participants were included in this analysis. There were 2504 incident lung cancer cases identified over an average 10.4-year follow-up. We applied Cox proportional hazards models to examine the associations between risk factors and incident lung cancer. We further developed a polygenic risk score and evaluated whether environmental factors modified the effect of genetic risk on incident lung cancer. Furthermore, we calculated the PAF for each risk factor, as well as their gene-environment additive interaction, and then combined them to create a weighted PAF that takes into consideration participants with overlapping risk factors.

RESULTS

Our analysis showed that smoking was the leading risk factor for lung cancer with a PAF of 63.73%. We observed additive interactions between smoking, PM_2.5, NO_x, and genetic risk, with PAFs of 17.85% (smoking-high genetic risk interaction), 10.79% (smoking-intermediate genetic risk interaction), 5.30% (NO_x-high genetic risk interaction), 6.55% (PM_2.5-high genetic risk interaction), and 4.99% (PM_2.5-intermediate genetic risk interaction). We estimated that 73.46% of lung cancer cases could be attributable to potentially modifiable risk factors after adjusting for the correlation between them.

CONCLUSION

High genetic risk and several modifiable factors may increase the risk of incident lung cancer. Participants with a high genetic risk may be more vulnerable to developing lung cancer if exposed to smoking and/or high air pollution. Our findings provide evidence that the majority of incident lung cancer cases could be prevented by eliminating modifiable risk factors.

The effects and contribution of childhood diseases on the geographical distribution of all-cause under-five mortality in Uganda

Introduction

Information on the causes of death among under-five children is key in designing and implementation of appropriate interventions. In Uganda, civil death registration is incomplete which limits the estimation of disease-related mortality burden especially at a local scale. In the absence of routine cause-specific data, we used household surveys to quantify the effects and contribution of main childhood diseases such as malaria, severe or moderate anaemia, severe or moderate malnutrition, diarrhoea and acute respiratory infections (ARIs) on all-cause under-five mortality (U5M) at national and sub-national levels. We related all-cause U5M with risks of childhood diseases after adjusting for geographical disparities in coverages of health interventions, socio-economic, environmental factors and disease co-endemicities.

Methods

Data on U5M, disease prevalence, socio-economic and intervention coverage indicators were obtained from the 2011 Demographic and Health Survey, while data on malaria prevalence were extracted from the 2009 Malaria Indicator Survey. Bayesian geostatistical Weibull proportional hazards models with spatially varying disease effects at sub-national scales were fitted to quantify the associations between childhood diseases and the U5M. Spatial correlation between clusters was incorporated via locational random effects while region-specific random effects with conditional autoregressive prior distributions modeled the geographical variation in the effects of childhood diseases. The models addressed geographical misalignment in the locations of the two surveys. The contribution of childhood diseases to under-five mortality was estimated using population attributable fractions.

Results

The overall U5M rate was 90 deaths per 1000 live births. Large regional variations in U5M rates were observed, lowest in Kampala at 56 and highest in the North-East at 152 per 1000 live births. National malaria parasitemia prevalence was 42%, with Kampala experiencing the lowest of 5% and the Mid-North the highest of 62%. About 27% of Ugandan children aged 6–59 months were severely or moderately anaemic; lowest in South-West (8%) and highest in East-Central (46%). Overall, 17% of children were either severely or moderately malnourished. The percentage of moderately/severely malnourished children varied by region with Kampala having the lowest (8%) and North-East the highest (45%). Nearly a quarter of the children under-five years were reported to have diarrhoea at national level, and this proportion was highest in East-Central (32%) and Mid-Eastern (33%) and lowest in South-West (14%). Overall, ARIs in the two weeks before the survey was 15%; highest in Mid-North (22%) and lowest in Central 1 (9%). At national level, the U5M was associated with prevalence of malaria (hazard ratio (HR) = 1.74; 95% BCI: 1.42, 2.16), severe or moderate anaemia (HR =1.37; 95% BCI: 1.20, 1.75), severe or moderate malnutrition (HR = 1.49; 95% BCI: 1.25, 1.66) and diarrhoea (HR = 1.61; 95% BCI: 1.31, 2.05). The relationship between malaria and U5M was important in the regions of Central 2, East-Central, Mid-North, North-East and West-Nile. Diarrhoea was associated with under-five deaths in Central 2, East-central, Mid-Eastern and Mid-Western. Moderate/severe malnutrition was associated with U5M in East-Central, Mid-Eastern and North-East. Moderate/severe anaemia was associated with deaths in Central 1, Kampala, Mid-North, Mid-Western, North-East, South-West and West-Nile.

At the national level, 97% (PAF = 96.9; 95%BCI: 94.4, 98.0), 91% (PAF = 90.9; 95%BCI: 84.4, 95.3), 89% (PAF = 89.3; 95%BCI: 76.0,93.8) and 93% (PAF = 93.3 95%BCI: 87.7,96.0) of the deaths among children less than five years in Uganda were attributable to malaria, severe/moderate anaemia, severe/moderate malnutrition and diarrhoea respectively. The attribution of malaria was comparable in Central 2, East-Central, Mid-North, North-East and West-Nile while severe/moderate anaemia was more common in all regions except Central 2, East-Central and Mid-Eastern. The attribution of diarrhoea in Central 2, East-Central, Mid-Eastern and Mid-Western was similar. The attribution of severe/moderate malnutrition was common in East-Central, Mid-Eastern and North-East.

Conclusion

In Uganda, the contribution and effects of childhood diseases on U5M vary by region. Majority of the under-five deaths are due to malaria, followed by diarrhoea, severe/moderate anaemia and severe/moderate malnutrition. Thus, strengthening disease-specific interventions especially in the affected regions may be an important strategy to accelerate progress towards the reduction of the U5M as per the SDG target by 2030. In particular, Indoor Residual Spraying, iron supplementation, deworming, exclusive breastfeeding, investment in nutrition and education in nutrition practices, oral rehydration therapy or recommended home fluid, improved sanitation facilities should be improved.

Incidence and associated risk factors for premature death in the Tehran Lipid and Glucose Study cohort, Iran

Background

The incidence and associated risk factors for premature death were investigated in a population-based cohort study in Iran.

Methods

A total of 7245 participants (3216 men), aged 30–70 years, were included. We conducted Cox proportional hazards models to identify the risk factors for premature death. For each risk factor, hazard ratio (HR), 95% confidence intervals (95% CI) and population attributable fraction (PAF) were calculated.

Results

After a median follow-up of 13.8 years, 262 premature deaths (153 in men) occurred. Underlying causes of premature deaths were cardiovascular disease (CVD) (n = 126), cancer (n = 51), road injuries (n = 15), sepsis and pneumonia (n = 9) and miscellaneous reasons (n = 61). The age-standardized incident rate of premature death was 2.35 per 1000 person years based on WHO standard population. Hypertension [HR 1.40, 95% CI (1.07–1.83)], diabetes (2.53, 1.94–3.29) and current smoking (1.58, 1.16–2.17) were significant risk factors for premature mortality; corresponding PAFs were 12.3, 22.4 and 9.2%, respectively. Overweight (body mass index (BMI): 25–29.9 kg/m²) (0.65, 0.49–0.87) and obesity (BMI ≥30 kg/m²) (0.67, 0.48–0.94) were associated with decreased premature mortality. After replacing general adiposity with central adiposity, we found no significant risk for the latter (0.92, 0.71–1.18). Moreover, when we excluded current smokers, those with prevalent cancer/cardiovascular disease and those with survival of less than 3 years, the inverse association between overweight (0.59, 0.39–0.88) and obesity (0.67, 0.43–1.04), generally remained unchanged; although, diabetes still showed a significant risk (2.62, 1.84–3.72).

Conclusions

Controlling three modifiable risk factors including diabetes, hypertension and smoking might potentially reduce mortality events by over 40%, and among these, prevention of diabetes should be prioritized to decrease burden of events. We didn’t confirm a negative impact of overweight and obesity status on premature mortality events.

Global burden of chronic obstructive pulmonary disease attributable to ambient ozone in 204 countries and territories during 1990-2019

Ambient ozone becomes one of significant environmental threats to chronic obstructive pulmonary disease (COPD) in recent decades. To date, however, few systematic analyses have been performed to quantify ozone-attributable disease burden, globally and regionally. In this study, we aimed to comprehensively depict the global trend of ozone-related COPD premature deaths and disability-adjusted life years (DALYs). We derived estimates of COPD burden attributable to ambient ozone for 204 countries and territories during 1990-2019 from the Global Burden of Disease Study 2019. We examined the number of deaths and DALYs, as well as age-standardized mortality rate (ASMR) and DALYs rate (ASDR) by sex, socio-demographic index (SDI), countries, and regions. Population attributable fractions (PAFs) were adopted to identify age groups vulnerable to ozone-related COPD. Estimated annual percentage changes (EAPCs) were calculated to assess the temporal trend of ozone-attributable COPD burden (e.g., ASMR and ASDR) between 1990 and 2019, using generalized linear models. Spearman rank correlation was applied to measure the relationships of estimated ASMR, ASDR, and EAPC with SDI. In 2019, COPD attributable to ambient ozone gave rise to 365.22 (95% uncertainty interval: 174.93 to 564.27) thousand deaths and 6.21 (2.99 to 9.63) million DALYs globally, representing a corresponding increase of 76.11% and 56.37% versus 1990. During 1990-2019, however, a yearly decline of 1.07% (0.81 to 1.33) was observed for ASMR and 1.30% (1.07 to 1.52) for ASDR. Considerable gender inequality continues in ozone-attributable COPD burden, with much greater impacts among men, and the gap is enlarged with the increase of age. In all age groups, the fractional contribution of ozone to COPD burden exhibited an overall increasing trend globally for both deaths (8.22% in 1990 versus 11.13% in 2019) and DALYs (6.70% in 1990 versus 8.34% in 2019). The burden of COPD caused by ambient ozone varied substantially by geographical and socioeconomic regions. In 2019, the greatest ASMR and ASDR were seen in South Asia, followed by East Asia and Central Sub-Saharan Africa. Despite the clear drop of age-standardized rates (EAPC<0) in high, high-middle, and middle SDI regions, ASMR and ASDR in low and low-middle SDI regions continuously raised between 1990 and 2019. Higher SDI was found to be associated with lower EAPCs in ASMR (r_s=-0.4405, p<0.001) and ASDR (r_s=-0.4510, p<0.001). Although the global ASMR and ASDR of COPD attributable to ambient ozone have decreased from 1990 to 2019, there has been an unnegligible increase in some low and low-middle SDI regions such as Southeast Asia, South Asia, and Andean Latin America. Findings may have some implications for formulating targeted plans and policies for future COPD prevention and ambient ozone management in different regions.

Population attributable fraction estimates for factors associated with different types of anaemia among women in Ethiopia: multilevel multinomial analysis

OBJECTIVE

This study aimed to identify factors for different levels of anaemia among Ethiopian women and to estimate the population attributable fraction (PAF).

DESIGN

This study was a detailed analysis of data of the 2016 Ethiopian Demographic and Health Survey data. Adjusted OR (AOR) with 95 % CI was computed using multilevel multinomial regression models, and the PAF were estimated using these AOR.

SETTING

This study was conducted in Ethiopia.

PARTICIPANTS

Women of reproductive age.

RESULTS

The PAF showed that the proportion of mild anaemia cases attributable to having no formal education was 14·6 % (95 % CI 3·4, 24·5), high gravidity (≥4) was 11·2 % (95 % CI 1·2, 19·9) and currently breast-feeding was 5·2 % (95 % CI 0·0, 10·7). Similarly, the proportion of moderate-severe anaemia cases attributable to being in a rural residence was 38·1 % (95 % CI 15·9, 54·8); poorest wealth quantile, 12·6 % (95 % CI 2·9, 24·6); giving birth in the last 5 years, 10·5 % (95 % CI 2·9, 18·2) and unimproved latrine facilities, 17 % (95 % CI 0, 32·5).

CONCLUSIONS

The PAF suggest that rural residency, low education, low wealth status, high parity, pregnancy and breast-feeding contribute substantially to the occurrence of anaemia among women in Ethiopia. Mild anaemia could be reduced by setting intervention strategies targeting women with low education, multigravida women and breast-feeding women, while preventing moderate-severe anaemia may require increasing income and improving living environments through the accessibility of hygienic latrines.

[Disease burden of diabetes attributable to high body mass index in China,1990-2016]

Objective: To analyze the burden of disease (BOD) on diabetes attributable to high BMI in China from 1990 to 2016. Methods: Data based on population of the 2016 Global Burden of Disease Study for China were used to analyze the attributable fractions (PAF) of BOD for diabetes attributable to high BMI. Measurements for attributable BOD of diabetes included disability adjusted life years (DALY), years of lost life (YLL), years living with disability (YLD), death number and mortality rate. The average world population from 2010 to 2035 was used as a reference. Results: In 2016, death number of diabetes attributable to high BMI was 40 310, which was significantly higher than that in 1990 (15 008). Age-standardized death rate of diabetes attributable to high BMI increased from 2.01/100 000 in 1990 to 2.60/100 000 in 2016, which showed a more significant increasing trend in both males and people aged 15-49 years. DALYs of diabetes attributable to high BMI increased from 1.09 million person years to 3.30 million person years. YLL and YLD also showed increasing trends. The highest increasing rate of YLD was in people aged 15-49 years. High BMI was responsible for 26.01% of the diabetes deaths in 2016 in China, an increase of 39.39% compared with that in 1990 (18.66%). Most provinces in China experienced a sharp increase of DALY of diabetes attributable to high BMI from 1990 to 2016. Inner Mongolia, Xinjiang, Zhejiang, Macao SAR, Sichuan and Qinghai had the most significant increase tendency in terms of DALY rate during this period. Conclusions: There was a rapid increase of the deaths and mortality rate of diabetes attributable to high BMI, causing a heavy disease burden, in China from 1990 to 2016. The BOD varied in both different age and gender groups. More attention should be paid to males and people aged 15-49 years in the prevention and control programs of diabetes.

An epidemiologic perspective on the stem cell hypothesis in human carcinogenesis

BACKGROUND

Tomasetti and Vogelstein have hypothesized that the patterns of cancer incidence in various cells and tissues are highly correlated with the estimated lifetime number of stem cell divisions. The authors reviewed the risks in tissues of 17 types of cancer from the United States and 69 additional countries. Positive correlations were observed consistently between the tissue - specific cancer incidence and the estimated lifetime number of stem cell divisions. The authors concluded that approximately two-thirds of global cancer incidence may be attributed to random DNA replication errors.

METHODS

An epidemiologic perspective is presented that may serve as a counterpoint in interpreting organ-specific cancer risks. The unifying nature of the Tomasetti/Vogelstein hypothesis must be viewed in the context of diverse and contrasting global trends and patterns of types and "causes" of cancers that are closely linked with economic development and cultural lifestyle practices. The presentation is organized by reviewing the global burden of cancer; concepts of causal inferences and counterfactual assumptions; multifactorial causes of hepatocellular carcinoma and a hierarchy of causes that varies internationally; tobacco carcinogenesis and the multiplex associations with 19 cancer sites and tissues; profile in contrasts in transit through the small and large intestine.

OBSERVATIONS AND CONCLUSIONS

It is readily recognized that DNA replication errors and number of stem cell divisions may vary in individuals and populations due to external environmental genotoxic chemicals and biologic agents, and internal hormonal and metabolic factors. There is a striking contrast in the risk of adenocarcinoma in the small intestine with that in the large intestine. Tomasetti and Vogelstein indicated that the cumulative number of divisions of stem cells over a lifetime in normal epithelial mucosal cells from colorectal cancer patients was 4 time greater than in the epithelial tissue from patients with adenocarcinoma of the small intestine. Their conclusion would suggest a "seed" and "soil" interaction rather than exclusively the independence of either component. Namely, that the contrasting physiological, biochemical, microbial and immunological features in the lumen and on the mucosal surface of the large intestine, in contrast to that in the small intestine, would foster molecular genetic and epigenetic events that are advantageous to neoplasia in the large intestine.

Potentially preventable dementia in a First Nations population in the Torres Strait and Northern Peninsula Area of North Queensland, Australia: A cross sectional analysis using population attributable fractions

Background

Dementia is highly prevalent among Australia's First Nations peoples, including Torres Strait Islander and Aboriginal peoples in Far North Queensland (FNQ). It is likely that historically recent exposure to modifiable risk factors underlies these rates, and a large proportion of dementia may be potentially preventable.

Methods

Data from two adult community health checks (2015-2018) were analyzed to determine the prevalence of 11 modifiable dementia risk factors among the First Nations residents of the Torres Strait and Northern Peninsula Area of FNQ. Population attributable fractions (PAF%) for dementia were calculated using age-standardized prevalence estimates derived from these health checks and relative risks obtained from previous meta-analyses in other populations. PAF% estimates were weighted for communality to account for overlap of risk factors.

Findings

Half (52·1%) of the dementia burden in this population may be attributed to 11 potentially modifiable risk factors. Hypertension (9·4%), diabetes mellitus (9·0%), obesity (8·0%), and smoking (5·3%) were the highest contributing risk factors. The contribution of depression (2·0%) and alcohol (0·3%) was lower than other global and national estimates. While the adjusted PAF% for social isolation was low based on the adult community health check data (1·6%), it was higher (4·2%) when official census data were analyzed.

Interpretation

These results suggest that a substantial proportion of dementia in FNQ First Nations peoples could potentially be prevented. Government investment in preventative health now is essential to reduce the future burden of dementia.

Funding

National Health and Medical Research Council (NHMRC, GNT1107140, GNT1191144, GNT1106175, GNT0631947).

Sex- and age-specific impacts of smoking, overweight/obesity, hypertension, and diabetes mellitus in the development of disabling dementia in a Japanese population

BACKGROUND

Sex- and age-specific impacts of cardiovascular risk factors on the development of dementia have not been well evaluated. We investigated these impacts of smoking, overweight/obesity, hypertension, and diabetes mellitus on the risk of disabling dementia.

METHODS

The study participants were 25,029 (10,134 men and 14,895 women) Japanese aged 40-74 years without disabling dementia at baseline (2008-2013). They were assessed on smoking status (non-current or current), overweight/obesity (body mass index ≥25 kg/m2 and ≥30 kg/m2, respectively), hypertension (systolic blood pressure ≥140 mmHg, diastolic blood pressure ≥90 mmHg or any antihypertensive medication use), and diabetes mellitus (a fasting serum glucose ≥126 mg/dL, non-fasting glucose ≥200 mg/dL, hemoglobin A1c ≥6.5% by the National Glycohemoglobin Standardization Program or glucose-lowering medication use) at baseline. Disabling dementia was identified as the level of care required ≥1 and cognitive disability grade ≥IIa according to the National Long-term Care Insurance Database. We used a Cox proportional regression model to estimate hazard ratios and 95% confidence intervals (95% CIs) of disabling dementia according to the cardiovascular risk factors and calculated the population attributable fractions (PAFs).

RESULTS

During a median follow-up of 9.1 years, 1,322 (606 men and 716 women) developed disabling dementia. Current smoking and hypertension were associated with a higher risk of disabling dementia in both sexes, whereas overweight or obesity was not associated with the risk in either sex. Diabetes mellitus was associated with a higher risk only in women (p for sex interaction = 0.04). The significant PAFs were 13% for smoking and 14% for hypertension in men and 3% for smoking, 12% for hypertension, and 5% for diabetes mellitus in women. The total PAFs of the significant risk factors were 28% in men and 20% in women. When stratified by age, hypertension in midlife (40-64 years) was associated with the increased risk in men, while diabetes mellitus in later-life (65-74 years) was so in women.

CONCLUSIONS

A substantial burden of disabling dementia was attributable to smoking, and hypertension in both sexes and diabetes mellitus in women, which may require the management of these cardiovascular risk factors to prevent dementia.

Improving job strain might reduce inequalities in cardiovascular disease mortality in european men

Unfavorable psychosocial working conditions can lead to cardiovascular disease (CVD) mortality. Lower-occupational groups typically experience unfavorable psychosocial working conditions as compared to higher-occupational groups. We investigate the extent to which CVD mortality inequalities might be reduced if psychosocial working conditions for manual workers are raised to the level experienced by non-manual workers (upward-leveling scenario). We also investigate what would occur if psychosocial working conditions among manual and non-manual workers are raised to better levels as observed in the 'ideal' region (best practice scenario). Individual-level CVD mortality data from 12 European countries were obtained from the EURO-GBD-SE project (1998-2007). Psychosocial working conditions data (i.e. job strain) were extracted from the European Working Conditions Survey (2005) and rate ratios from literature reviews. Population attributable fractions (PAF) and two counterfactual scenarios (namely, upward-leveling scenario and best-practice scenario) were developed to examine employed male non-manual and manual workers. Results appeared to show that CVD mortality might be reduced in men when unfavorable psychosocial working conditions are improved for manual workers (PAF = 7.7%, 95% CI: 6.5-10.0). The upward-leveling scenario seems to reduce CVD mortality inequalities for manual workers, by 13-74%. Best-practice scenario shows the largest reduction in CVD mortality in the Baltic region (87 deaths per 100,000 person years). Findings suggest that rendering job strain in manual workers to the level experienced by non-manual workers might substantially reduce CVD mortality inequalities in European men.

Population modifiable risk factors associated with neonatal mortality in 35 sub-Saharan Africa countries: analysis of data from demographic and health surveys

Background

Sub-Saharan Africa (SSA) has the highest burden of neonatal mortality in the world. Identifying the most critical modifiable risk factors is imperative for reducing neonatal mortality rates. This study is the first to calculate population-attributable fractions (PAFs) for modifiable risk factors of neonatal mortality in SSA.

Methods

We analysed the most recent Demographic and Health Surveys data sets from 35 SSA countries conducted between 2010 and 2022. Generalized linear latent and mixed models were used to estimate odds ratios (ORs) along with 95% confidence intervals (CIs). PAFs adjusted for communality were calculated using ORs and prevalence estimates for key modifiable risk factors. Subregional analyses were conducted to examine variations in modifiable risk factors for neonatal mortality across Central, Eastern, Southern, and Western SSA regions.

Findings

In this study, we included 255,891 live births in the five years before the survey. The highest PAFs of neonatal mortality among singleton children were attributed to delayed initiation of breastfeeding (>1 h after birth: PAF = 23.88%; 95% CI: 15.91, 24.86), uncleaned cooking fuel (PAF = 5.27%; 95% CI: 1.41, 8.73), mother's lacking formal education (PAF = 4.34%; 95% CI: 1.15, 6.31), mother's lacking tetanus vaccination (PAF = 3.54%; 95% CI: 1.55, 4.92), and infrequent antenatal care (ANC) visits (PAF = 2.45; 95% CI: 0.76, 3.63). Together, these five modifiable risk factors were associated with 39.49% (95% CI: 21.13, 48.44) of neonatal deaths among singleton children in SSA. Our subregional analyses revealed some variations in modifiable risk factors for neonatal mortality. Notably, delayed initiation of breastfeeding consistently contributed to the highest PAFs of neonatal mortality across all four regions of SSA: Central, Eastern, Southern, and Western SSA.

Interpretation

The PAF estimates in the present study indicate that a considerable proportion of neonatal deaths in SSA are preventable. We identified five modifiable risk factors that accounted for approximately 40% of neonatal deaths in SSA. The findings have policy implications.

Funding

None.

The prevalence of chronic pain and its impact on activities of daily living disability and depressive symptoms according to multiple definitions in a Japanese population: the Hisayama study

Objectives

This study aimed to compare the prevalence of chronic pain using various definitions from previous studies and to determine the optimal definition for detecting chronic pain associated with physical and emotional dysfunction in a general Japanese population.

Methods

A total of 2700 community-dwelling Japanese residents aged ≥40 years were assessed for chronic pain and its components of duration, frequency, and intensity. The activities of daily living (ADL) disability and depressive symptoms of participants were also evaluated using the modified Lankin Scale and Patient Health Questionnaire-9. The odds ratios and the population attributable fractions (PAFs) for ADL disability and depressive symptoms were estimated using a logistic regression model.

Results

The prevalence of chronic pain varied greatly by definition, ranging from 13% for pain defined as pain duration ≥3 months, pain frequency ≥ twice a week, and pain intensity of ≥50 mm by a visual analogue scale (VAS) to 48% for a simple definition of pain duration ≥3 months. The PAFs for ADL disability and depressive symptoms were relatively high at 33% in participants with pain duration of ≥6 months and 30% in those with pain frequency of ≥twice a week, while the VAS ≥50 mm group had a low PAF of 12%.

Conclusion

For screening people with chronic pain and ADL disability or depressive symptoms, the criteria of pain duration and pain frequency yielded essentially identical results, while the criterion of pain intensity risked overlooking individuals with chronic pain and these associated symptoms.

Erratum: Potentially preventable dementia in a First Nations population in the Torres Strait and Northern Peninsula Area of North Queensland, Australia: a cross sectional analysis using population attributable fractions

[This corrects the article DOI: 10.1016/j.lanwpc.2023.100855.][This corrects the article DOI: 10.1016/j.lanwpc.2022.100532.].

The social cost of high sodium diet in Singapore

High sodium (Na) diet is one of the leading behavioural risks of disease identified in the Singapore Burden of Disease Study. We aim to estimate the cost attributable to a high Na diet in Singapore in 2019 from a societal perspective by employing a prevalence-based approach in cost-of-illness studies. We extracted national-level healthcare data and population attributable fractions by sex and age. Costs included direct and indirect costs from inpatient treatment and productivity losses. In 2019, the annual societal cost attributable to a high Na diet was conservatively estimated to be USA$262 million (95 % uncertainty interval (UI) 218, 359 million). At least USA$67·8 million (95 % UI 48·4, 120 million) and USA$194 million (95 % UI 153, 274 million) could be saved on healthcare and indirect costs, respectively, if the daily Na intake of Singaporeans was reduced to an average of 3 g. Overall, males had higher costs compared with females at USA$221 million (95 % UI 174, 312 million) and USA$41·1 million (95 % UI 33·5, 61·7 million), respectively. Productivity loss from foregone wages due to premature mortality had the largest cost at USA$191 million (95 % UI 150, 271 million). CVD had the largest healthcare expenditure at USA$61·4 million (95 % UI 41·6, 113 million), driven by ischaemic heart disease at USA$41·0 million (95 % UI 21·4, 88·9 million). Our study found that reducing Na intake could reduce future healthcare expenditures and productivity losses. This result is vital for policy evaluation in a rapidly ageing society like Singapore, where the burden of diseases associated with high Na diet is expected to increase.

Temporal trends and disparities of population attributable fractions of modifiable risk factors for dementia in China: a time-series study of the China health and retirement longitudinal study (2011-2018)

Background

In China, dementia poses a significant public health challenge, exacerbated by an ageing population and lifestyle changes. This study assesses the temporal trends and disparities in the population-attributable fractions (PAFs) of modifiable risk factors (MRFs) for new-onset dementia from 2011 to 2018.

Methods

We used data from the China Health and Retirement Longitudinal Study (CHARLS), covering 75,214 person-waves. We calculated PAFs for 12 MRFs identified by the Lancet Commission (including six early-to mid-life factors and six late-life factors). We also determined the individual weighted PAFs (IW-PAFs) for each risk factor. Subgroup analyses were conducted by sex, socio-economic status (SES), and geographic location.

Findings

The overall PAF for dementia MRFs had a slight increase from 45.36% in 2011 to 52.46% in 2018, yet this change wasn't statistically significant. During 2011-2018, the most contributing modifiable risk was low education (average IW-PAF 11.3%), followed by depression, hypertension, smoking, and physical inactivity. Over the eight-year period, IW-PAFs for risk factors like low education, hypertension, hearing loss, smoking, and air pollution showed decreasing trends, while others increased, but none of these changes were statistically significant. Sex-specific analysis revealed higher IW-PAFs for traumatic brain injury (TBI), social isolation, and depression in women, and for alcohol and smoking in men. The decline in IW-PAF for men's hearing loss were significant. Lower-income individuals had higher overall MRF PAFs, largely due to later-life factors like depression. Early-life factors, such as TBI and low education, also contributed to SES disparities. Rural areas reported higher overall MRF PAFs, driven by factors like depression, low education, and hearing loss. The study also found that the gap in MRF PAFs across different SES groups or regions either remained constant or increased over the study period.

Interpretation

The study reveals a slight but non-significant increase in dementia's MRF PAF in China, underscoring the persistent relevance of these risk factors. The findings highlight the need for targeted public health strategies, considering the demographic and regional differences, to effectively tackle and reduce dementia risk in China's diverse population.

Funding

This work was supported by the PKU Young Scholarship in Global Health and Development.

Impact of Parental Mental Health and Poverty on the Health of the Next Generation: A Multi-Trajectory Analysis Using the UK Millennium Cohort Study

PURPOSE

Exposure to parental mental ill-health and poverty in childhood impact health across the lifecourse. Both maternal and paternal mental health may be important influences, but few studies have unpicked the complex interrelationships between these exposures and family poverty for later health.

METHODS

We used longitudinal data on 10,500 children from the nationally representative UK millennium cohort study. Trajectories of poverty, maternal mental health, and secondary caregiver mental health were constructed from child age of 9 months through to 14 years. We assessed the associations of these trajectories with mental health outcomes at the age of 17 years. Population-attributable fractions were calculated to quantify the contribution of caregivers' mental health problems and poverty to adverse outcomes at the country level.

RESULTS

We identified five distinct trajectories. Compared with children with low poverty and good parental mental health, those who experienced poverty and poor primary or secondary caregiver mental health (53%) had worse outcomes. Children exposed to both persistent poverty and poor caregiver mental health were at markedly increased risk of socioemotional behavioural problems (aOR 4.2; 95% CI 2.7-6.7), mental health problems (aOR 2.5; CI 1.6-3.9), and cognitive disability (aOR 1.7; CI 1.1-2.5). We estimate that 40% of socioemotional behavioural problems at the age of 17 were attributable to persistent parental caregivers' mental health problems and poverty.

DISCUSSION

More than half of children growing up in the UK are persistently exposed to either one or both of poor caregiver mental health and family poverty. The combination of these exposures is strongly associated with adverse health outcomes in the next generation.

Population modifiable risk factors associated with under-5 acute respiratory tract infections and diarrhoea in 25 countries in sub-Saharan Africa (2014-2021): an analysis of data from demographic and health surveys

Background

Identifying the critical modifiable risk factors for acute respiratory tract infections (ARIs) and diarrhoea is crucial to reduce the burden of disease and mortality among children under 5 years of age in sub-Saharan Africa (SSA) and ultimately achieving the Sustainable Development Goals (SDGs). We investigated the modifiable risk factors of ARI and diarrhoea among children under five using nationally representative surveys.

Methods

We used the most recent demographic and health survey (DHS) data (2014-2021) from 25 SSA countries, encompassing a total of 253,167 children. Countries were selected based on the availability of recent datasets (e.g., DHS-VII or DHS-VIII) that represent the current socioeconomic situations. Generalised linear latent mixed models were used to compute odds ratios (ORs). Population attributable fractions (PAFs) were calculated using adjusted ORs and prevalence estimates for key modifiable risk factors among ARI and diarrhoeal cases.

Findings

This study involved 253,167 children, with a mean age of 28.7 (±17.3) months, and 50.5% were male. The highest PAFs for ARI were attributed to unclean cooking fuel (PAF = 15.7%; 95% CI: 8.1, 23.1), poor maternal education (PAF = 13.4%; 95% CI: 8.7, 18.5), delayed initiation of breastfeeding (PAF = 12.4%; 95% CI: 9.0, 15.3), and poor toilets (PAF = 8.5%; 95% CI: 4.7, 11.9). These four modifiable risk factors contributed to 41.5% (95% CI: 27.2, 52.9) of ARI cases in SSA. The largest PAFs of diarrhoea were observed for unclean cooking fuel (PAF = 17.3%; 95% CI: 13.5, 22.3), delayed initiation of breastfeeding (PAF = 9.2%; 95% CI: 7.5, 10.5), household poverty (PAF = 7.0%; 95% CI: 5.0, 9.1) and poor maternal education (PAF = 5.6%; 95% CI: 2.9, 8.8). These four modifiable risk factors contributed to 34.0% (95% CI: 26.2, 42.3) of cases of diarrhoea in SSA.

Interpretation

This cross-sectional study identified four modifiable risk factors for ARI and diarrhoea that should be a priority for policymakers in SSA. Enhancing home-based care and leveraging female community health workers is crucial for accelerating the reduction in under-5 mortality linked to ARI and diarrhoea in SSA.

Funding

None.

Sex-specific population attributable risk factors for cardiovascular and all-cause mortality in the general population: Findings from the China PEACE million persons project

Little evidence exists regarding the sex-specific population attributable risk factors for cardiovascular and all-cause mortality in the Chinese general population. We used a sub-cohort of the China Patient-Centered Evaluative Assessment of Cardiac Events million persons project to evaluate the overall and sex-specific associations and population attributable fractions (PAFs) of twelve risk factors for cardiovascular and all-cause mortality. 95,469 participants were included between January 2016 and December 2020. The twelve risk factors (including four socioeconomic status and eight modifiable risk factors) were collected or measured at baseline. The outcomes of the study were all-cause mortality and cardiovascular mortality. Overall, 60.7% (N = 57,971) were women, and the mean age was 54.3 ± 10.2 years. After a median of 3.52 years of follow-up, 1311 (1.4%) people died, and 362 (0.4%) people died of cardiovascular causes. Majorities of risk factors were significantly associated with all-cause and cardiovascular mortality, and suboptimal blood pressure and low educational attainment were the two leading attributable risk factors for all-cause and cardiovascular mortality. The twelve risk factors collectively explained 72.4% (95% confidence interval (CI): 63.5, 79.2) and 84.0% (95% CI: 71.1, 91.1) of PAFs for all-cause and cardiovascular mortality. When stratified by sex, men had more risk factors that were significantly attributable to mortality than women, whereas low educational attainment had a more pronounced impact on female cardiovascular health. This study found that the twelve risk factors collectively explained a significant proportion of PAFs for all-cause and cardiovascular mortality. Several sex-related disparities in the associations between risk factors and mortality were noted.

Population attributable fractions of adverse childhood experiences for emotional problems and self-harming behaviors among middle school students in China

The population attributable fractions of health outcomes attributed to adverse childhood experiences (ACEs) among Chinese middle school students is unknown. Of all the 22,868 middle school students, 29.8 % had exposure to four or more ACEs. Findings showed a graded relationship between ACE scores and those adverse outcomes. The PAFs of six outcomes attributed to experiencing ≥ 4 ACEs ranged from 23.1 % to 44.2 %. The results emphasized the significance of preventive interventions to alleviate the negative legacies of ACEs.

Comparison of Population Attributable Fractions of Cancer Incidence and Mortality Linked to Excess Body Weight in Korea from 2015 to 2030

BACKGRUOUND

The increasing rate of excess body weight (EBW) in the global population has led to growing health concerns, including cancer-related EBW. We aimed to estimate the population attributable fraction (PAF) of cancer incidence and deaths linked to EBW in Korean individuals from 2015 to 2030 and to compare its value with various body mass index cutoffs.

METHODS

Levin's formula was used to calculate the PAF; the prevalence rates were computed using the Korean National Health and Nutrition Examination Survey data, while the relative risks of specific cancers related to EBW were estimated based on the results of Korean cohort studies. To account for the 15-year latency period when estimating the PAF in 2020, the prevalence rates from 2015 and attributable cases or deaths from 2020 were used.

RESULTS

The PAF attributed to EBW was similar for both cancer incidence and deaths using either the World Health Organization (WHO) Asian-Pacific region standard or a modified Asian standard, with the WHO standard yielding the lowest values. In the Korean population, the PAFs of EBW for cancer incidence were 2.96% in men and 3.61% in women, while those for cancer deaths were 0.67% in men and 3.06% in women in 2020. Additionally, PAFs showed a gradual increase in both sexes until 2030.

CONCLUSION

The EBW continues to have a significant impact on cancer incidence and deaths in Korea. Effective prevention strategies targeting the reduction of this modifiable risk factor can substantially decrease the cancer burden.

Temporal trends in population attributable fractions of modifiable risk factors for dementia: a time-series study of the English Longitudinal Study of Ageing (2004-2019)

BACKGROUND

Interest in modifiable risk factors (MRFs) for dementia is high, given the personal, social, and economic impact of the disorder, especially in ageing societies such as the United Kingdom. Exploring the population attributable fraction (PAF) of dementia attributable to MRFs and how this may have changed over time remains unclear. Unravelling the temporal dynamics of MRFs is crucial for informing the development of evidence-based and effective public health policies. This investigation examined the temporal trajectories of MRFs for dementia in England.

METHODS

We used data from the English Longitudinal Study of Ageing, a panel study over eight waves collected between 2004 and 2019 (76,904 interviews in total). We calculated the PAFs for twelve MRFs (including six early- to mid-life factors and six late-life factors), as recommended by the Lancet Commission, and the individual weighted PAFs (IW-PAFs) for each risk factor. Temporal trends were analysed to understand the changes in the overall PAF and IW-PAF over the study period. Subgroup analyses were conducted by sex and socioeconomic status (SES).

RESULTS

The overall PAF for dementia MRFs changed from 46.73% in 2004/2005 to 36.79% in 2018/2019, though this trend was not statistically significant. During 2004-2019, hypertension, with an average IW-PAF of 8.21%, was the primary modifiable determinant of dementia, followed by obesity (6.16%), social isolation (5.61%), hearing loss (4.81%), depression (4.72%), low education (4.63%), physical inactivity (3.26%), diabetes mellitus (2.49%), smoking (2.0%), excessive alcohol consumption (1.16%), air pollution (0.42%), and traumatic brain injury (TBI) (0.26%). During 2004-2019, only IW-PAFs of low education, social isolation, and smoking showed significant decreasing trends, while IW-PAFs of other factors either did not change significantly or increased (including TBI, diabetes mellitus, and air pollution). Upon sex-specific disaggregation, a higher overall PAF for MRFs was found among women, predominantly associated with later-life risk factors, most notably social isolation, depression, and physical inactivity. Additionally, hearing loss, classified as an early- to mid-life factor, played a supplementary role in the identified sex disparity. A comparable discrepancy was evident upon PAF evaluation by SES, with lower income groups experiencing a higher dementia risk, largely tied to later-life factors such as social isolation, physical inactivity, depression, and smoking. Early- to mid-life factors, in particular, low education and obesity, were also observed to contribute to the SES-associated divergence in dementia risk. Temporal PAF and IW-PAF trends, stratified by sex and SES, revealed that MRF PAF gaps across sex or SES categories have persisted or increased.

CONCLUSIONS

In England, there was little change over time in the proportion of dementia attributable to known modifiable risk factors. The observed trends underscore the continuing relevance of these risk factors and the need for targeted public health strategies to address them.