Burden of type 2 diabetes mellitus and its risk factors in North Africa and the Middle East, 1990–2019: findings from the Global Burden of Disease study 2019

Diabetes mellitus is a major global public health concern affecting populations worldwide. It encompasses different types, such as type 1, type 2 (T2D), and gestational diabetes. In T2D, the main factor contributing to abnormal blood sugar levels is the inability of β-cells to adequately compensate for peripheral insulin resistance. Additionally, disruptions in hormonal balance and organokines further contribute to the dysregulation of blood sugar in T2D. Metabolites from various tissues also play a role in the onset and progression of this health concern [1].

This disease places a significant socio-economic burden on governments and causes psychological distress for patients and their families [2]. According to the 9th edition of the International Diabetes Federation Diabetes report, the Middle East and North Africa had the highest age-standardized prevalence of diabetes worldwide in 2019, standing at 12.2%. The report also predicts that by 2045, the prevalence is projected to increase further to 13.9% in this region [3]. In addition, it is estimated that diabetes mellitus is a contributing factor in one out of nine deaths among individuals aged 20 to 79 years old. Approximately 11.5% of annual global deaths are attributed to diabetes, with percentages ranging from 6.8% in the Africa Region to 16.2% in the Middle East and North Africa [4]. The rising prevalence of type 2 diabetes mellitus (T2DM), which is the most common subtype of diabetes mellitus, is influenced by multiple factors. These include unhealthy lifestyle choices, the shift towards a more Westernized diet, obesity, industrialization, epigenetics, limited access to appropriate healthcare services, and other behavioral and environmental risk factors [5].

The prevalence of T2DM varies across countries in the region due to the differences in various societal dimensions mentioned earlier. Factors such as lifestyle, dietary patterns, cultural practices, socioeconomic conditions, healthcare infrastructure, and access to preventive healthcare services can all contribute to the variations in T2DM prevalence among different countries in the region [6‐10]. Several studies have been conducted to examine the burden of diabetes mellitus and its associated metabolic disorders, focusing on specific risk factors in individual countries, regions, or globally. However, there is a need for comprehensive, multidimensional assessments that take into account the parameters mentioned earlier at both national and international levels. Such assessments could offer valuable insights into the effective management of T2DM.

The Global Burden of Diseases, Injuries, and Risk Factors (GBD) studies are examples of such studies that have provided suitable frameworks to quantify the comparative magnitude of health loss due to a specific disease and injury as well as risk factors of certain diseases.

In the present study, we tried to figure out the age and sex pattern of this disease in this region and across 21 countries. Considering 600 million people living in this region and the growing trend of T2DM across the world, encourages us to focus on the burden and attributed burden provided by the GBD study to explore what is going on here. In addition, there is a knowledge gap about the epidemiologic status of T2DM in this region, we conducted this study to reflect a comprehensive outlook of T2DM burden and attributed the burden to its risk factors. Accordingly, we aimed to provide the burden and attributable burden to metabolic, behavioral, and environmental exposures of T2DM at the regional and national levels for 21 countries in the region from 1990 to 2019.

In the present study, data from GBD study 2019 were used to estimate the burden and attributable burden of T2DM in the region. The entry data were obtained through GBD results (http://​ghdx.​healthdata.​org/​gbd-results-tool) and compare (https://​vizhub.​healthdata.​org/​gbd-compare) tools which are prepared by the Institute for Health Metrics and Evaluation (IHME). Details of GBD study 2019 are provided elsewhere [11‐13]. Briefly, GBD 2019 study can provide a ground to estimate the prevalence of exposure and attributable mortalities, Years Lived with Disability (YLDs), Years of Life Lost (YLLs), and Disability-Adjusted Life Years (DALYs) for a cluster of diseases in both genders (separately and combined) and 23 age groups from 1990 to 2019. It contains information of 204 countries and territories classified in 21 GBD regions and 7 super-regions.

For the current paper, we used the data of GBD 2019 study for T2DM in 21 countries in the region considering age group, sex, and location. According to the Institute for Health Metrics and Evaluation (IHME), countries in this region are as follows: Afghanistan, Algeria, Bahrain, Egypt, Iran (Islamic Republic of), Iraq, Jordan, Kuwait, Lebanon, Libya, Morocco, Oman, Palestine, Qatar, Saudi Arabia, Sudan, Syrian Arab Republic, Tunisia, Turkey, United Arab Emirates (UAE), and Yemen. To define T2DM, the International Classification of Diseases 10th Revision (ICD-10) codes of E11-E11.1, E11.3-E11.9 were used.

Our findings indicated that the prevalence and incidence of T2DM increased from 1990 to 2019. No considerable differences were found between two genders in the prevalence and incidence of T2DM; however, deaths and DALYs in females were greater than men. Qatar ranked the first in both incidence and prevalence of T2DM among the countries in the region. However, the report by the International Diabetes Federation (IDF) in 2019 showed that Pakistan ranked the first among the countries in the region regarding the numbers of people with diabetes [17]. During these years in some countries such as Qatar, Kuwait, and UAE rapid economic growth and urbanization have occurred that affected life expectancy, while in some countries such as Palestine, Iraq, Lebanon, and Afghanistan due to some dramatic political changes, war, and sanction controlling non-communicable diseases (NCDs) including T2DM was faced some problems. Although Qatar ranked first in the incidence and prevalence of T2DM, reported deaths and DALYs in this country were relatively low compared to the numbers of countries. Relatively low deaths and DALYs for T2DM may be partly explained by Qatar national response to diabetes. Action plans for obesity, diabetes, and/or physical activity are also provided in some countries such as Iran, Bahrain, Qatar, Kuwait, UAE. These programs can take part in the prevention and the management of diabetes There is also national registries for diabetes and national surveys for identification of risk factors in several countries including Bahrain, Qatar, Iran, Jordan, and Kuwait [18]. However, due to the remarkable number of individuals suffered from T2DM in some countries controlling and monitoring the status with high quality services are difficult.

Our findings regarding greater deaths in diabetic females were similar to those have reached so far [19, 20]. A systematic review and meta-analysis by Xu et al., demonstrated that all-cause mortality in females with diabetes was higher than men [20]. Although it is not fully understood why the number of deaths in women was higher than men, several possible mechanisms can explain a part of this. Based on evidence, sex differences can play a pivotal role in the management of diabetes and mortality rates between males and females. Diabetic men vs. women may be diagnosed earlier and men with diabetes are likely to receive more suitable therapeutic interventions and greater comprehensive care [20]. This factor along with more attention of men to self-care and adherence to therapies vs. women can affect the status of disease and complications [21]. It has been also indicated that diabetic men more than women received recommended care processes [22]. Importantly, there is compelling evidence suggesting that men, when adhering to the same treatment plan, tend to attain a higher percentage of treatment goals for managing diabetes and mitigating other mortality risk factors. This difference in outcomes can be attributed to a range of factors, including variances in biological characteristics, hormonal influences, and behavioral tendencies [19].

In the Present study, we also found that the increase in the incidence of T2DM cannot be fully explained by population growth and aging. It was affected mostly by age-structure change. The most prevalence and incidence during these years were observed in those aged 75 to 80 and 50 to 60 years old, respectively. Mortality, DALY, and YLD rates increased following this growth in the region. However, the number of deaths decreased in less than one-third countries in the region.

The increased incidence and prevalence of T2DM and mortality can be attributed to several factors, mainly a combination of metabolic and environmental factors. Urbanization, modernization, and industrialization in the countries of the region can result in changes in lifestyle such as physical activity and dietary habits. These factors can induce overweight/obesity and metabolic disorders, and provide a ground for developing T2DM [23].

Our findings confirmed the previous evidence on the roles of metabolic, behavioral, and environmental factors in the mortality from T2DM. Based on our findings, the most important risk factor for T2DM mortality is due to high Fasting Blood Glucose [FPG]. High BMI, air pollution and low physical activity were ranked next.

Although the proportion of about all risk factors in the deaths of T2DM did not change considerably during these years, high intake of processed meat and sugar sweetened beverages participated in the most portions of deaths from T2DM. Thus, primary prevention must be paid specific attention by policy makers and clinicians. National preventive programs with the aims of promoting healthy lifestyle and considering various dimensions including social, economic, cultural, and regional characteristics of each country in the region must be given high priority in the health care agenda.

Public educational programs and tax policy interventions for unhealthy foods such as processed meat and sugar-sweetened beverages (SSB) can be helpful to control diabetes and mortality related to these chronic diseases. Based on estimation in Germany, for instance, combined tax interventions containing a 50% price increase for sugar-sweetened beverages, red meat and its products, and tobacco in 2020 can lead to a 0.95% decrease in the prevalence of T2DM in 2040 that corresponds to 640,000 fewer cases of T2DM [24]. However, such interventions alone are not sufficient to attenuate the incidence and prevalence of T2DM in years ahead [24]. In a systematic review study, Zhou et al., indicated that lifestyle interventions in high-risk populations were cost-effective to prevent diabetes from a health care system or a societal perspective. Among population-based interventions, taxing SSB was cost saving from both governmental and health care system perspectives. However, it revealed that findings for community-based education programs and modifications to build environment are inconsistent [25]. One of WHO's program called “best buys” contained some strategies such as raising taxes on unhealthy foods that are implemented in some countries to tackle sharp increase in the cases with diabetes and other NCDs [18]. In the present study, we shed light on the ranking of risk factors attributed to mortality from T2DM for each country in the region. Findings can be helpful for policy makers to set priorities and allocate resources for the prevention of this NCD in real-world settings.

Although our findings showed that high BMI was one of the main factors for mortality in both men and women with T2DM in the region, a systematic review and meta-analysis showed an association between high BMI and all-cause mortality in T2DM in women only [26]. In this systematic review and meta-analysis, no subgroup analysis was performed based on location. Thus, it may be due to different patterns in each region across the world.

Changes in the proportion of high temperature in mortality rate of T2DM increased by 50% in 2019 compared to 1990. Temperature is a new environmental risk factor introduced in GBD 2019. Recent studies have shown a link between high temperature and the risk of developing diabetes and gestational diabetes.

Temperature is a new environmental risk factor provided in GBD 2019. Recent studies revealed the association between high temperature and the risk of diabetes and gestational diabetes mellitus [27‐29]. This link can originate through a multifactorial pathway containing social, biological, geophysical, environmental, and economic factors [30].

Apart from multi-dimensional transition (e.g., a shift from rural to urban, socioeconomic development, adherence to unhealthy and sedentary lifestyle) in the region, several countries in the Middle East encounter into war, political instability, forced migration, climate change, and social instability. These issues can lead to a significant challenge in health care and social services [18]. Although countries in this region in most cases have similarities including religion, development level, ethnicity, urbanization, and level of health care, there are differences in culture, income, and level of healthcare that involve in the quality of care and the burden of diseases including T2DM. In addition, many countries have developed national diabetes treatment guidelines (specific strategy and standard protocol). But some countries such as Libya and Yemen have not yet provided a standard protocol.

In addition, based on the last accessible report, action plans for diabetes (e.g. in Egypt, Libya, Oman, Sudan, Yemen), weight management (in most countries), and physical activity have not been existed in several countries. National diabetes registry and national risk factor survey in which glycemic status have been considered are other examples of implementations to collect data on diabetes status that have not been reported in several countries [18].

Other issues are related to knowledge gaps and poor attitude in diabetes self-management, poor compliance with healthy life style recommendations and medications, lack of social support and no access to healthy environment that can involve in increasing the burden of T2DM in the region [18]. Therefore, health care providers prepare appropriate education and other intervention strategies to help prevent and control diabetes, taking into account local sociocultural practices, gender, and age.

Based on the current status of primary care in the management of diabetes in the region more focus should be done to strengthen and improvement the delivery of health servicesaa [31].

The burden of T2DM, as measured by the number of deaths, DALYs, and YLDs, continues to increase in the region from 1990 to 2019. The age-standardized incidence rate of T2DM has also shown an upward trend in many areas. The burden of T2DM attributed to modifiable risk factors remains high, highlighting the need for targeted public health programs focused on prevention, screening, and monitoring of patients with type 2 diabetes.

To reduce the growth and disease burden of T2DM in the region, it is important to address modifiable risk factors, promote healthy aging throughout life, improve healthcare services, and aim to decrease disability and premature death associated with T2DM. The study's strength lies in considering the burden and risk factors across all 21 countries in the region. However, the study has some limitations, such as not accounting for psychological factors like stress, which play a significant role in diabetes management. Additionally, it does not include epidemiological information for gestational diabetes mellitus and its associated risk factors. It is recommended that future GBD protocols consider the effects of the COVID-19 pandemic.