Growing social inequality in the prevalence of type 2 diabetes in Canada, 2004-2012

Bridging ethics and epidemiology: Modelling ethical standards of health equity

Health inequities are differences in health that are 'unjust'. Yet, despite competing ethical views about what counts as an 'unjust difference in health', theoretical insights from ethics have not been systematically integrated into epidemiological research. Using diabetes as an example, we explore the impact of adopting different ethical standards of health equity on population health outcomes. Specifically, we explore how the implementation of population-level weight-loss interventions using different ethical standards of equity impacts the intervention's implementation and resultant population health outcomes. We conducted a risk prediction modelling study using the nationally representative 2015-16 Canadian Community Health Survey (n = 75,044, 54% women). We used the Diabetes Population Risk Tool (DPoRT) to calculate individual-level 10-year diabetes risk. Hypothetical weight-loss interventions were modelled in individuals with overweight or obesity based on each ethical standard: 1) health sufficiency (reduce DPoRT risk below a high-risk threshold (16.5%); 2) health equality (equalize DPoRT risk to the low risk group (5%)); 3) social-health sufficiency (reduce DPoRT risk <16.5 in individuals with lower education); 4) social-health equality (equalize DPoRT risk to the level of individuals with high education). For each scenario, we calculated intervention impacts, diabetes cases prevented or delayed, and relative and absolute educational inequities in diabetes. Overall, we estimated that achieving health sufficiency (i.e., all individuals below the diabetes risk threshold) was more feasible than achieving health equality (i.e., diabetes risk equalized for all individuals), requiring smaller initial investments and fewer interventions; however, fewer diabetes cases were prevented or delayed. Further, targeting only diabetes inequalities related to education reduced the target population size and number of interventions required, but consequently resulted in even fewer diabetes cases prevented or delayed. Using diabetes as an example, we found that an explicit, ethically-informed definition of health equity is essential to guide population-level interventions that aim to reduce health inequities.

Socioeconomic inequalities in diabetes prevalence: the case of Egypt between 2008 and 2015

BACKGROUND

There is a steady increase in diabetes prevalence globally and many studies imply that high socioeconomic status (SES) is inversely related to diabetes prevalence. However, there is scarcity in literature from countries like Egypt regarding this topic.

METHODS

This study aims to investigate prevalence of diabetes in Egypt between 2008 and 2015, and the effect of SES. Diabetes prevalence -based on self-reports of past diagnosis- was measured using two datasets Egypt DHS 2008 (10,917 participants) and EHIS 2015 (16,485 participants). Logistic regression and odds ratios (ORs) with 95% confidence intervals (CIs) were applied for diabetes controlling for age, gender, educational level, employment status and place of residence. Extend of difference in diabetes prevalence between the two time points was measured by combining the two datasets using the EDHS 2008 as reference.

RESULTS

Diabetes prevalence was higher in 2015 (4.83%) compared to 2008 (3.48%). It was more in women at both time points (4.08% and 5.16% in 2008 and 2015 respectively) compared to men (2.80% and 4.43% in 2008 and 2015 respectively). Older age and living in urban areas were positively related to diabetes prevalence at both time points. Men had a significant higher chance of developing diabetes in 2015 (OR = 1.45, p-value = 0.001). Men with higher education had higher chance of developing diabetes (OR = 1.76), in contrast to women (OR = 0.59). Employment decreased the chance of developing diabetes for men (OR = .72), but had minimal effect on women (OR = 1.06).

CONCLUSION

Diabetes prevalence in Egypt has increased between the years 2008 and 2015 and evident social inequalities were found. Women had more diabetes than men and were more affected with low SES. Unlike women, highly educated men had higher chance of developing diabetes in 2015 compared to 2008. This might be attributed to behavioral and sociocultural factors.

Socioeconomic inequalities in diabetes prevalence: the case of South Africa between 2003 and 2016

BACKGROUND

Diabetes is a growing epidemic worldwide and the effect of socioeconomic status (SES) is frequently acknowledged in the literature. This study aims to compare the effect of SES on diabetes prevalence in South Africa between 2003 and 2016. In addition, vulnerable groups regarding diabetes development in 2016 will be identified.

METHODS

Using DHS data there were 8,006 participants (59.19% women) in 2003 and 10,292 participants (59.42% women) in 2016. Logistic regression and odds ratios (ORs) with 95% confidence intervals (CIs) were calculated for diabetes by age, gender, educational level and place of residence. To identify vulnerable groups with high risk of developing diabetes in 2016, the method of p-value based regression tree analysis was applied using "wealth index" and "weight perception" as additional variables.

RESULTS

There was an increase in diabetes prevalence from 3.86% in 2003 to 4.46% in 2016. Women had more risk of developing diabetes at both time points (27% in 2003 and 24% in 2016 more risk). Increase in age and living in urban areas were associated with more risk of developing diabetes at both time points. There was no specific pattern regarding risk of developing diabetes and educational level in case of women. However, men who completed secondary school or had a higher diploma or above had more risk of developing diabetes in 2016 (OR = 2.24 and 4.67 respectively). Vulnerable groups who have higher risk of developing diabetes in 2016 were participants aged "60 years or older" with a wealth index of "rich" or "richer", followed by participants from the same age group who were "poor" or "poorer" and participants aged "40-59 years" with a wealth index of "rich" or "richer". Subsequently were participants from the age group "15-39 years" with a weight perception of "overweight" or "obese".

CONCLUSION

Diabetes prevalence increased in South Africa between 2003 and 2016. Main risk factors were age, gender and living in urban areas. Men with high educational level were more at risk of developing diabetes in 2016. Vulnerable groups in 2016 were participants 40 years and older, particularly with high SES. This was followed by younger participants who were obese or overweight.

Remission as an Emerging Therapeutic Target in Type 2 Diabetes in the Era of New Glucose-Lowering Agents: Benefits, Challenges, and Treatment Approaches

Type 2 diabetes mellitus (T2DM) is a progressive disease with a growing prevalence, associated with an increased risk of complications. The introduction of new classes of antidiabetic drugs into clinical practice has dramatically changed the landscape of diabetes therapy. However, despite the progress made in the pharmacotherapy of T2DM, mitigating the burden of the disease on individuals, societies and health care systems remains a challenge. Remission has recently emerged as a therapeutic target in T2DM, achievable through a wide range of interventions. Recent studies have shown that extensive lifestyle changes, such as weight reduction, bariatric surgery, and intensive glucose lowering therapy, can prompt the remission of diabetes, but some unanswered questions remain regarding its long-term effects on diabetic complications. Metabolic surgery and novel classes of glucose-lowering medications are currently the most effective interventions to induce weight loss and by extension remission in patients with diabetes; however, the ideal strategy to achieve the long-term maintenance of remission remains doubtful. In this narrative review, we discuss the available therapeutic approaches to target the remission of diabetes through personalized multimodal care, based on the latest evidence.

Gender-specific trends of educational inequality in diagnosed diabetes from 1999 to 2014 in Hong Kong: a serial cross-sectional study of 97,481 community-dwelling Chinese adults

Background

Gender differences in the trend of educational inequality in diabetes have been widely observed in the Western populations, indicating the increasing importance of educational attainment as a social determinant of diabetes among women. Nonetheless, relevant evidence is scarce in developed Asian settings for comparisons. This study examined the gender-specific trends of educational inequality in diagnosed diabetes in Hong Kong between 1999 and 2014.

Methods

A series of eight territory-wide population-representative samples of 97,481 community-dwelling Hong Kong Chinese adults aged 45 or above were surveyed between 1999 and 2014. Regression-based Relative Index of Inequality (RII) and age-standardized Slope Index of Inequality (SII) were adopted to examine the extent and trend of gender-specific educational inequality in self-reported physician-diagnosed diabetes.

Results

Age-standardized prevalence of diabetes increased in both genders over time, with a steeper surge among men. In addition, educational inequalities in diabetes, in both relative and absolute terms, significantly widened among women over the study period (annual RII change = 1.04; 95% CI = 1.02–1.07, annual SII change = 0.36%; 95% CI = 0.16–0.56%), with the peak in 2011 (RII = 2.44; 95% CI = 1.83–3.24, SII = 9.21%; 95% CI = 6.47–11.96%). However, no significant widening inequality was found among men. Further adjustment for household income level did not attenuate the observed educational inequality.

Conclusions

Despite a greater increase in diabetes prevalence among men, disparity in diabetes substantially widened across education levels among women in the past decade in Hong Kong. The gender perspective should be taken into considerations for policy making to alleviate the prevalence surge and rising educational inequality in diabetes.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12963-021-00268-x.

Burden of disease and costs associated with type 2 diabetes in emerging and established markets: systematic review analyses

Objectives: To estimate the clinical and economic burden of type 2 diabetes (T2D) in established (EST) and emerging markets (EMG).Methods: Three systematic literature reviews were conducted in MEDLINE and Embase to capture all relevant publications reporting 1) the epidemiology of T2D and complications in T2D and 2) the economic burden of T2D and associated complications.Results: In total, 294 studies were included in this analysis. Evidence indicates a high and increasing overall prevalence of T2D globally, ranging up to 23% in EMG markets and 14% in EST markets. Undiagnosed cases were higher in EMG versus EST markets (up to 67% vs 38%), potentially due to a lack of education and disease awareness in certain regions, that could lead to important clinical and economic consequences. Poor glycemic control was associated with the development of several complications (e.g. retinopathy, cardiovascular diseases and nephropathy) that increase the risk of morbidity and mortality. Direct costs were up to 9-fold higher in patients with vs without T2D-related complications.Conclusions: The burden of T2D, related complications and inherent costs are higher in emerging versus established market countries. This review explores potential strategies to reduce costs and enhance outcomes of T2D treatment in developing countries.

Socioeconomic inequalities in type 2 diabetes in employed individuals, nonworking spouses and pensioners

Type 2 diabetes (T2D) is a rising global epidemic with lower socioeconomic groups being more affected. Considering specific population subgroups to examine prevalence and socioeconomic inequalities in T2D is rare. Moreover, using one indicator to depict socioeconomic inequalities in health is a common practice despite evidence on differences in what different socioeconomic indicators ought to measure. This study has two aims:

1. Examine the prevalence of T2D in employed individuals, nonworking spouses and pensioners.

2. Examine socioeconomic inequalities in T2D in the three population subgroups and determine the explanatory power of income, education and occupation in employed individuals and nonworking spouses.

This study is based on claims data from a statutory health insurance provider in Lower Saxony, Germany. T2D prevalence in the period between 2013 and 2017 was examined in employed individuals, nonworking spouses and pensioners. Multivariate logistic regression analysis was applied to examine socioeconomic inequalities in T2D in the three population subgroups. Explanatory power of the three socioeconomic indicators was determined by deviance analysis.

Results showed that T2D prevalence was four times higher in male nonworking spouses (24.2%) and 2.6 times higher in female nonworking spouses (12.7%) compared to employed men (6.4%) and women (4.7%) respectively, while it accounted for 40% of men and 36% of women in pensioners. T2D inequalities emerged for all three socioeconomic indicators and were observed in the three subgroups. School education had the highest explanatory power in employed men and women and male nonworking spouses.

Nonworking spouses are an important target group in T2D prevention interventions. The three socioeconomic indicators have independent effects and differ in their explanatory power where low school education appears to be a major risk factor. It can be discussed that health literacy and the associated health behavior play a role in mediating the association between school education and T2D.

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Different population subgroups have varying risk levels for type 2 diabetes prevalence.

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The population subgroup “nonworking spouses” is an important target group for type 2 diabetes prevention interventions.

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Education, occupation and income have different explanatory powers in health inequalities.

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The level of school education is an important determinant of health inequalities in type 2 diabetes.

Universal drug coverage and income-related disparities in glycaemic control

AIMS

To examine whether income-related disparities in glycaemic control decline after the age of 65 years, when publicly funded universal drug insurance is acquired in Ontario, Canada.

METHODS

We conducted a population-based cross-sectional study using linked administrative healthcare databases. Adults with diabetes, aged 40-89 years, with available HbA_1c data were included (N = 716 297). Income was based on median neighbourhood household income. Multiple linear regression was used to test for effect modification of age ≥65 years on the relationship between income and HbA_1c .

RESULTS

There was a significant inverse association between income and HbA_1c level. After adjusting for baseline factors, the effect of income on HbA_1c level was significantly greater for individuals aged <65 years (mean difference HbA_1c for lowest vs highest income group +2.5 mmol/mol, 95% CI +2.3 to +2.7 [+0.23%, 95% CI 0.21 to 0.24]) than for those aged ≥65 years (+1.2 mmol/mol, 95% CI +1.0 to +1.3 [+0.11%, 95% CI 0.10 to 0.12]; P < 0.0001 for interaction).

CONCLUSIONS

Despite universal access to healthcare, people with diabetes with lower incomes had significantly worse glycaemic control compared with their counterparts on higher incomes. However, income gradients in glycaemic control were markedly reduced after the age of 65 years, possibly as a result of access to prescription drug coverage.

Impact of mobile health in diabetic retinopathy awareness and eye care behavior among Indigenous women

BACKGROUND

Diabetes is increasingly widespread among Indigenous people, and diabetic retinopathy (DR) is a diabetes eye complication and a common cause of vision loss among adults in Canada. Indigenous women have a high risk of diabetes which increases their risk for DR. This study explored utilizing mobile health (mHealth) via text messages to provide DR awareness and improve diabetic-eye care behavior. This study identified the changes in DR awareness and eye care behavior due to a mHealth education intervention among Indigenous women with or at risk of diabetes.

METHODS

A pre-post study which adopted an embedded concurrent mixed methods approach guided by self-determination theory and the medicine wheel. Study participants were First Nations and Métis women living with or at risk of diabetes in Saskatoon, Canada. Data was collected via sharing circles and a DR knowledge, attitude, and practice survey. Pre-intervention participants' baseline information on DR knowledge and behavior were obtained from participants. After that, participants received daily text messages on diabetes-eye related information for 12 weeks. Post-intervention, the impact of the mHealth intervention on DR awareness and eye care behavior was assessed.

RESULTS

Following the intervention, the DR knowledge, attitude, and practice scores significantly improved. Individuals living with diabetes had increased DR attitude and practice post-scores compared to those at risk of diabetes. Older women had a lower pre-post change in practice scores compared to younger women. The mHealth intervention provided a holistic approach to support diabetes-eye care and empowered the study participants to eat healthily, take medication as prescribed, and have regular medical and eye check-ups.

CONCLUSIONS

The mHealth education intervention increased DR awareness and fostered a change in diabetes-eye care behavior. Health information via text messaging can motivate, provide support, and empower individuals as well as prevent and manage chronic conditions and reduce the risk of complications.

Widespread and widely widening? Examining absolute socioeconomic health inequalities in northern Sweden across twelve health indicators

BACKGROUND

Socioeconomic inequalities in health is a widely studied topic. However, epidemiological research tends to focus on one or a few outcomes conditioned on one indicator, overlooking the fact that health inequalities can vary depending on the outcome studied and the indicator used. To bridge this gap, this study aims to provide a comprehensive picture of the patterns of socioeconomic health inequalities in Northern Sweden over time, across a range of health outcomes, using an 'outcome-wide' epidemiological approach.

METHOD

Cross-sectional data from three waves of the 'Health on Equal Terms' survey, distributed in 2006, 2010 and 2014 were used. Firstly, socioeconomic inequalities by income and education for twelve outcomes (self-rated health, self-rated dental health, overweight, hypertension, diabetes, long-term illness, stress, depression, psychological distress, smoking, risky alcohol consumption, and physical inactivity) were examined by calculating the Slope Index of Inequality. Secondly, time trends for each outcome and socioeconomic indicator were estimated.

RESULTS

Income inequalities increased for psychological distress and physical inactivity in men as well as for self-rated health, overweight, hypertension, long-term illness, and smoking among women. Educational inequalities increased for hypertension, long-term illness, and stress (the latter favouring lower education) in women. The only instance of decreasing income inequalities was seen for long-term illness in men, while education inequalities decreased for long-term illness in men and poor self-rated health, poor self-rated dental health, and smoking in women.

CONCLUSION

Patterns of absolute socioeconomic inequalities in health vary by health and socioeconomic indicator, as well as between men and women. Overall, trends appear more stagnant in men while they fluctuate in women. Income inequalities seem to be generally greater than educational inequalities when looking across several different health indicators, a message that can only be derived from this type of outcome-wide study. These disparate findings suggest that generalised and universal statements about the development of health inequalities can be too simplistic and potentially misleading. Nonetheless, despite inequalities being complex, they do exist and tend to increase. Thus, an outcome-wide approach is a valuable method which should be utilised to generate evidence for prioritisations of policy decisions.

Evolving Trends in the Epidemiology, Risk Factors, and Prevention of Type 2 Diabetes: A Review

Currently, the global prevalence of diabetes is 8.8%. This figure is expected to increase worldwide, with the largest changes projected to occur in low- and middle-income countries. The aging of the world's population and substantial increases in obesity have contributed to the rise in diabetes. Global shifts in lifestyles have led to the adoption of unhealthy behaviours such as physical inactivity and poorer-quality diets. Correspondingly, diabetes is a rapidly-increasing problem in higher- as well as lower-income countries. In Canada, the prevalence of diabetes increased approximately 70% in the past decade. Although diabetes-related mortality rates have decreased in Canada, the number of people affected by diabetes has continued to grow because of a surge in the number of new diabetes cases. Non-European ethnic groups and individuals of lower socioeconomic status have been disproportionately affected by diabetes and its risk factors. Clinical trials have proven efficacy in reducing the onset of diabetes in high-risk populations through diet and physical activity interventions. However, these findings have not been broadly implemented into the Canadian health care context. In this article we review the evolving epidemiology of type 2 diabetes, with regard to trends in occurrence rates and prevalence; the role of risk factors including those related to ethnicity, obesity, diet, physical activity, socioeconomic status, prediabetes, and pregnancy; and the identification of critical windows for lifestyle intervention. Identifying high-risk populations and addressing the upstream determinants and risk factors of diabetes might prove to be effective diabetes prevention strategies to curb the current diabetes epidemic.

Temporal trends in educational inequalities in non-communicable diseases in Korea, 2007-2015

Background

Socioeconomic inequalities in non-communicable diseases are known to exist; however there is a paucity of research describing the secular trends in these inequalities. To this end, the current study aims to explore the recent time trends in social patterning of selected non-communicable diseases among Korean adults between 2007 and 2015.

Methods

Using data from the Korea National Health and Nutrition Examination Survey (KNHANES), temporal trends in socioeconomic inequalities in diabetes, arthritis, asthma and depressive symptoms were assessed across three time points. Respondents were adults aged 20 years or over (N = 47,091, 20,180 men and 26,911 women). Socioeconomic circumstance was assessed based on highest level of educational attainment. We estimated prevalence ratios with 95% confidence intervals using Poisson regression with robust variance estimation (adjusted for age, smoking status, alcohol consumption, obesity, and physical activity) separately for men and women. The magnitude of the inequalities was computed using the relative index of inequality (RII).

Results

In men, diabetes was not associated with educational attainment, while there was evidence of a negative association in women across surveys. Similar inverse associations were found with arthritis and depressive symptoms, but these associations were less clear for asthma. RII showed a non-significant increasing trend in educational disparities in depressive symptoms. Meanwhile, relative inequalities in diabetes, arthritis and asthma have narrowed. These trends were, in general, more pronounced in women.

Conclusions

The findings of this study indicate higher burden of selected NCDs among the lower educational groups, particularly among women. In addition, our results indicated some improvements in inequalities in diabetes, arthritis and asthma in recent years. These findings have important implications for understanding the causes of social patterning of NCDs and for the targeting of effective interventions.

Inequalities in Hypertension and Diabetes in Canada: Intersections between Racial Identity, Gender, and Income

A growing body of research from the United States informed by intersectionality theory indicates that racial identity, gender, and income are often entwined with one another as determinants of health in unexpectedly complex ways. Research of this kind from Canada is scarce, however. Using data pooled from ten cycles (2001-2013) of the Canadian Community Health Survey, we regressed hypertension (HT) and diabetes (DM) on income in subsamples of Black women (n = 3,506), White women (n = 336,341), Black men (n = 2,806) and White men (n = 271,260). An increase of one decile in income was associated with lower odds of hypertension and diabetes among White men (OR_HT = .98, 95% CI (.97, .99); OR_DM = .93, 95% CI (.92, .94)) and White women (OR_HT = .95, 95% CI (.95, .96); OR_DM = .90, 95% CI (.89, .91)). In contrast, an increase of one decile in income was not associated with either health outcome among Black men (OR_HT = .99, 95% CI (.92, 1.06); OR_DM = .99, 95% CI (.91, 1.08)) and strongly associated with both outcomes among Black women (OR_HT = .86, 95% CI (.80, .92); OR_DM = .83, 95% CI (.75, .92)). Our findings highlight the complexity of the unequal distribution of hypertension and diabetes, which includes inordinately high risks of both outcomes for poor Black women and an absence of associations between income and both outcomes for Black men in Canada. These results suggest that an intersectionality framework can contribute to uncovering health inequalities in Canada.

Socioeconomic gradient in health in Canada: Is the gap widening or narrowing?

BACKGROUND

Notwithstanding a general improvement in health status, the socioeconomic gradient in health remains a public health challenge worldwide.

OBJECTIVE

Using longitudinal data from the National Population Health Survey (NPHS, n=17,276), we examined trends in socioeconomic gradients in two health indicators, viz. the Health Utility Index (HUI) and the Frailty Index (FI), among Canadian adults (25 years and older) between 1998/9-2010/11.

METHODS

The relative and slope indices of inequality (RII and SII, respectively) were employed to summarize income- and education-based inequality in the FI and the HUI in Canada as whole, and in five regions: the Atlantic provinces, Quebec, Ontario, the Prairies and British Columbia.

RESULTS

We found that education- and income-related inequalities in health were present in all five regions of Canada. The estimated RIIs and SIIs suggested that education-related inequalities in the FI and the HUI increased among women. The results also revealed that relative and absolute income-related inequalities in the HUI increased in Canada, especially among women. Both absolute and relative inequalities indicated that income-related inequalities in the HUI increased in Quebec and in the Prairies over time.

CONCLUSION

Persistent and growing socioeconomic inequalities in health in Canada over the past one and half decades should warrant more attention. The mechanisms underlying socioeconomic-related inequalities in Canada are less clear. Therefore, further studies are required to identify effective polices to reduce the socioeconomic gradient in health in Canada.