Type 2 Diabetes
Type 2 diabetes incidence has increased dramatically in obese people. Thus understanding obesity and overweight would be useful. Being overweight means your body has more fat than is needed in an optimally healthy state. Being overweight is common especially in places where food supplies are plentiful and lifestyles are sedentary. The number of people who are overweight has reached epidemic proportions globally, with more than 1 billion adults being either overweight or obese in 2003. In 2013 this increased to more than 2 billion. Increases have been observed across all age groups.
The degree to which a person is overweight is generally measured by body mass index (BMI). BMI is a measure of a person’s weight taking into account their weight (mass) in kilograms divided by the square of the person’s height in metres. The units thus are kg/m^2 but BMI measures are typically used and written without units.
BMI provides a significantly more accurate representation of body fat content than simply measuring a person’s weight. It is only moderately correlated with both body fat percentage and body fat mass (R2 of 0.68). It does not take into account certain factors such as pregnancy or bodybuilding; however, the BMI is an accurate reflection of fat percentage in the majority of the adult population.
Overweight is defined as a BMI of 25 or more, thus it includes pre-obesity defined as a BMI between 25 and 30 and obesity as defined by a BMI of 30 or more. Pre-obese and overweight however are often used interchangeably thus giving overweight a common definition of a BMI of between 25 -30. Obesity is associated with the onset of diabetes.
Type 2 Diabetes (T2D) (formerly adult-onset diabetes) is a relative insulin deficiency that occurs when peripheral cells become insulin resistant or there is insufficient insulin production, often asymptomatic to mild in the early-stages. Over 90% of diabetic cases are T2D, usually affecting adults. Other risk factors for T2D include genetic predisposition, poor diet, physical inactivity, increasing age and ethnicity, high blood pressure, Impaired Glucose Tolerance (IGT), history of gestational diabetes and poor nutrition during pregnancy.
The global prevalence of diabetes was estimated at over 422 million people in 2017 and is forecast to reach 552 million by 2030.[3],[4] The global prevalence rate was 8.3%. Over 50% of people with diabetes remain undiagnosed worldwide, from lack of symptoms or misdiagnosis allowing secondary complications to develop. Of those that are diagnosed only 50% receive care. Genders are similarly affected by diabetes, with 51% male and 49% female across cases. The age group most affected by diabetes is 40-59 years followed by 60-79 years, which is expected to account for the highest number of diabetes patients by 2030.
Economic Costs
Except reduction in productivity, diabetes accounted for US$471 billion or over 11% of global healthcare expenditure in adults (20-79 years) in 2012, and is expected to exceed US$595 billion by 2030. Around 80% of countries spend between 5-18% of their total direct healthcare expenditure on diabetes, representing a global average of US$1274 per person.
Almost 80% of healthcare expenditure occurs in high-income countries with less than 20% of the diabetes population (US$5064), which contrasts to 20% expenditure in low-middle income countries with 80% of the diabetes population (US$271). Healthcare costs for people with diabetes are 2-3 times higher than for people without the disease. Increasing public healthcare costs are driving the need for a diabetes cure that will reduce the enormous economic burden on society. It is estimated that hospitalisation accounts for 55% of diabetes care costs from diabetes complications and co-morbidities, followed by 18% for ambulatory costs, 7% for antidiabetes drugs and 20% for other drugs.[5]
Human Costs
In addition to the increased morbidity and mortality, diabetes imposes an economic burden on individuals, families and society including direct costs from individual treatment costs, public healthcare and associated care costs, as well as indirect costs from lost productivity, absenteeism and deaths, the 4-5th leading cause of death in high-income countries.
Hyperglycaemia disturbs energy metabolism affecting tissue and organ functioning that leads to serious secondary diabetes complications 10-20 years after onset including cardiovascular disease, kidney failure, blindness, nerve damage and limb amputations, resulting in increased morbidity, mortality and healthcare costs. Importantly, in addition to quality of life significantly decreased, T2D people’s life expectancy is reduced on average by 10 years.
Over 4.8 million people died due to diabetes in 2012. Over 50% of deaths were due to cardiovascular disease. Nearly 50% of diabetes related deaths occurs in people under the age of 60, and deaths in low-middle income countries (1.1 – 1.3 per 1000) almost double compared to high-income countries (0.5 per 1000) that have the highest diabetes healthcare spend.
Prevention
T2D can be prevented through lifestyle changes such as weight loss to achieve a healthy body weight, regular physical activity, healthy balanced diet, quitting smoking, reduced stress and improved sleep patterns. Maintaining blood glucose levels, blood pressure and cholesterol close to normal can delay or prevent diabetes complications and requires regular monitoring.