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Skip to 0 minutes and 12 seconds Diabetes is a global problem. The number of people with diabetes worldwide is increasing steadily. According to the NCD Risk Factor Collaboration the number of adults with diabetes (aged 20-79 years) increased from 108 million in 1980 to 422 million in 2014. 2017 data from the International Diabetes Federation revise this estimate to 425 million people. If these trends continue, 629 million adults worldwide are expected to have diabetes by 2045. The largest increases in the prevalence of diabetes have been in seen low and middle income countries. For example, the increase across Sub Saharan African countries has been over 500%. By 2025, 75% of all people living with diabetes will be in low- and middle-income countries.

Skip to 1 minute and 10 seconds 90% of all people living with diabetes have type 2 diabetes. The global prevalence of type 2 diabetes has more than doubled over the past 30 years for men and women. It’s also increasing amongst children and adolescents in many parts of the world. Lifestyle changes which lead to excessive weight and obesity are considered to be the key risk factors for type 2 diabetes along with an ageing population and urbanisation. Diabetes is a growing challenge in both urban and rural environments. Risk factors are the features, characteristics or experiences that increase someones likelihood of developing a disease.

Skip to 1 minute and 51 seconds We need to understand and manage the risk factors for type 2 diabetes in every population before we can begin to reduce the incidence (that is the occurrence of new cases) as well as progression of the disease.

Skip to 2 minutes and 5 seconds In diabetes we group the known risk factors into: - non-modifiable risk factors, where we cannot change or influence the impact. - modifiable risk factors, where we have a known action to reduce impact. Non-modifiable risk factors for type 2 diabetes include age, family history or genetic predisposition and race. Certain groups such as Afro Caribbeans, Hispanics, Pacific Islanders and Asian Americans are predisposed to the condition. A pre-existing history of hypertension, heart disease or stroke, is also a non-modifiable risk factor for developing type 2 diabetes. Modifiable risk factors include excess weight (particularly around the stomach), lack of exercise and unhealthy eating (such a high carbohydrate diet).

Skip to 2 minutes and 54 seconds All these factors can be targeted to reduce development of new cases or influence progression of the disease in high risk groups.

Skip to 3 minutes and 4 seconds The public health control strategy for diabetes includes: - screening high risk individuals to detect diabetes early. - supporting people to change their lifestyle. - and education to help people with diabetes manage the condition. Type 1 is the major type of diabetes seen in young people. It accounts for over 85% of cases seen in people less than 20 years old. There are large geographical variations in the incidence of type 1 diabetes worldwide. Incidence is found to be higher in Europe and North America than in Asian and South American countries. Rates of increase have been found to be highest in the youngest age group, 0 to 4 years olds.

Skip to 3 minutes and 45 seconds This earlier onset implies a longer burden of disease as well as the more immediate challenge of caring for a toddler with type 1 diabetes. Incidence rates of type 1 diabetes decline after puberty and stabilise in young adulthood (15 to 29 years old). The incidence of type 1 diabetes is lower in adults than children, although 1 in 4 people are diagnosed with diabetes as adults and clinical presentation can occur at any age. The incidence of type 1 diabetes began to rise in western populations in the middle of the 20th century and is still increasing in many places. These changing trends suggest a link between the environment and genetic susceptibility.

Skip to 4 minutes and 28 seconds For example, Ethiopian immigrants to Israel develop higher rates of type 1 diabetes than those who remain in Ethiopia.

Skip to 4 minutes and 37 seconds A seasonal pattern in the onset of type 1 diabetes has been found in the Northern hemisphere, with more cases being found in late autumn and winter compared to summer months. This may be associated with the prevalence of infectious diseases at this time which are thought to act as environmental triggers to type 1 diabetes in those with a genetic susceptibility. Risk factors for type 1 diabetes include a family history of the condition, for example a parent or sibling, and race. Caucasians are more likely to develop type 1 diabetes than AfroCaribbean or Asian people. Over 199 million women are currently living with diabetes worldwide and this is projected to increase to 313 million women by 2040.

Skip to 5 minutes and 24 seconds 2 out of 5 women with diabetes are of reproductive age. In 2015, the global prevalence of pregnant women with hyperglycaemia - high blood sugar - was estimated to be 16.2%, affecting 20.9 million live births. 90% of hyperglycaemia in pregnancy is found in low and middle-income countries. 1 in 7 births is affected by gestational diabetes. Gestational diabetes is more common in overweight women aged 30 years and over with a family history of diabetes. Between 15 and 45% of babies bornr to women with gestational diabetes weigh more than 4 kilogrammes. And this can lead to higher risk of complications at birth. It is unclear if there is an ethnic predisposition to gestational diabetes.

Skip to 6 minutes and 13 seconds 50% of women who have gestational diabetes are at a high risk of developing subsequent type 2 diabetes 5 to 10 years after delivery. The rate of complications is also higher during pregnancy for women with pre-existing diabetes. Diabetes accounts for 4 million deaths each year, which is 1 death every 8 seconds. This is 10.7% of all mortality in the 20-79 year age group, based on the IDF 2017 data, and is higher than the combined number of deaths from infectious diseases worldwide. Approximately 47% of the deaths from diabetes are in people under the age of 60 yrs.

Skip to 6 minutes and 57 seconds People with diabetes are much more likely to require health service intervention and there is a huge impact from the condition on the socioeconomic resources of a country.

Skip to 7 minutes and 8 seconds In summary: - Global trends indicate that diabetes is a major public health problem, particularly in low- and middle-income countries. - More research data is needed to understand geographical variations in the prevalence and incidence of diabetes. - Public health action is based on managing the modifiable risk factors for diabetes to reduce new cases and also progression of disease. - Provision of health services for early detection and management of diabetes requires planning and appropriate resources allocation.

The global challenge of diabetes

Key demographic, economic, social and cultural changes across the world are influencing the growing number of people with diabetes, particularly in low- and middle-income settings. Overcoming diabetes is a many sided and complex challenge for individuals, populations and health systems.

To plan and evaluate effective public health intervention strategies for diabetes we need to know some key data:

  • How many people have diabetes in our population at present?
  • What are the rates of the complications caused by the disease?

A recent report from the Lancet commission clearly highlights the challenges health systems face from lack of data:

“Most countries do not have data or data collection systems that are sufficiently reliable to enable mounting of a commensurate health-system response. To plan such a response requires high-quality, population-representative data on both current burdens and associated demographic factors and that systems for longitudinal data collection be put in place.”
(Zhou et al. 2016)

Worldwide prevalence trends of diabetes have been estimated from a range of carefully selected population based studies. Considerable research needs to be undertaken to understand the complex interactions between obesity, socioeconomic status and type 2 diabetes.

For example, to understand the high prevalence of diabetes in low and middle income countries research has been undertaken to understand the impact of the “thrifty phenotype” which describes obesity related health problems that occur later in life amongst people who have experienced poor nutrition during foetal and early life.

Scarcity of high quality data further limits our ability to reliably appreciate trends over time and consider the burden of complications from diabetes. Responsive health systems need to identify and manage diabetes earlier.

As you watch this video, consider why it is important to have information on magnitude and trends in diabetes. How can we use it to influence patient care?

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This video is from the free online course:

Diabetic Eye Disease: Building Capacity To Prevent Blindness

London School of Hygiene & Tropical Medicine