Imagine a pandemic. A disease comes into a community and then spreads across borders, causing disability and death in its path. Scientists fight to contain its spread, and doctors try to mitigate its effects. Most people associate this kind of scenario with a pathogen: a virus or bacteria, like HIV or avian flu, that has found a way to exploit the human body. In fact, however, the overwhelming majority of pandemics are the result of noncommunicable diseases that are not spread by pathogens: conditions like cancer, heart disease, and type 2 diabetes.
Today, these conditions are affecting every level of society, crippling development and causing profound disability in every country in the world. While diseases like swine flu and malaria make the headlines, noncommunicable diseases cause more than double the deaths caused by all infectious diseases combined, including HIV/AIDS. Type 2 diabetes alone affects more than 300 million people, and these numbers are expected to almost double in the next twenty years. Low- and middle-income countries are particularly affected because they allocate few resources to diabetes, and most people do not see it as a threat, in part because of the silent and gradual nature of the disease.
People with type 2 diabetes can go for years without experiencing any symptoms, during which time excess sugar in the blood is already causing damage to the kidneys, eyes, nerves, and heart. High blood glucose is particularly damaging to nerves in the eyes, hands, and feet. As excessive glucose causes damage, nerves lose sensation and sores can develop in the absence of pain. These sores can lead to infections and, eventually, amputations. A similar problem occurs with the optic nerve, which is responsible for sight.
Diabetes is not only a major cause of blindness and amputation, but also increases the risk of heart attack and stroke, which are the most common causes of death among people with diabetes. The disease is also associated with a number of other conditions, from chronic kidney disease, obesity, and depression to tuberculosis and malaria. Once diabetes develops, managing the condition with medications and a healthy lifestyle can prevent some of the most serious complications. There is no cure for diabetes, however, and the costs to individual quality of life and to a community are very high.
Type 2 diabetes results from a prolonged period of unhealthy eating, low levels of exercise, a family history of diabetes, and other factors. According to Helen McGuire, Senior Diabetes Education and Health Systems Specialist with the International Diabetes Federation, “The development of type 2 diabetes occurs over time. If diagnosed, it’s crucial to take the diagnosis seriously and take action. This is an opportunity to examine your lifestyle and identify the changes you need and want to make to improve your health, such as increasing your activity, managing your weight, and eating a balanced diet with lots of vegetables.”
“Managing diabetes has often been described as a balancing act. With the help of their healthcare team, people with diabetes need to manage their blood glucose, blood lipids, and blood pressure in order to prevent or delay complications,” says McGuire, adding, “Medications can help to keep these factors in the target range, but food and activity play a very important role.”
Today, the best chance to reduce the burden of diabetes in the world is prevention. Fortunately, type 2 diabetes is preventable for most people. Diabetes, heart disease, obesity, and some cancers share many of the same risk factors, a number of which can be modified by changes in lifestyle. Other factors cannot be changed, but understanding one’s risk of developing diabetes is a key component of preventing the condition.
The influence of individual risk factors can be different for different communities. For example, the genetic profile of people from the Pacific Islands puts them at higher risk for diabetes from being overweight. Although assessing the exact risk for diabetes can be different in various populations, a number of risk factors contribute to diabetes across all ethnicities and borders, including being overweight, a family history of diabetes, low levels of physical activity, increasing age, high blood pressure, impaired glucose sensitivity, and insulin resistance. These risk factors work together to affect a person’s chances of getting diabetes. No one factor is solely responsible, and each has a role.
The gold standard for identifying new cases and people at high risk of diabetes is through a blood test. The most widely-used and established test is the oral glucose tolerance test (OGTT), which looks at the efficiency with which the body processes glucose. While this test provides the best picture of how the body is performing and the risk for diabetes, it must be performed by a trained healthcare professional and requires time, resources, and a controlled environment. Many factors, however, can be assessed by individuals on their own, including being over the age of 45, being overweight, having a history of diabetes in the family, eating an unhealthy diet high in sugars and fats, and having a low level of physical activity.
One of the factors with the strongest link to risk for diabetes is being overweight or obese. The most common way of measuring this is to calculate body mass index (BMI). The calculation, which is based on a person’s height and weight, is then compared to ranges to determine if a person is underweight, normal, overweight, or obese for their body size. While this measure is commonly used in clinics, it can be difficult for people to calculate off-hand. They may not be able to measure their weight accurately, and understanding the measurement conversions and having access to the calculation are also potential barriers.
Recently, evidence has been growing that while BMI can be an indicator for diabetes risk, the distribution of fat around the abdomen is also important. A number of studies have shown that a large waist circumference relative to body size is related to high blood pressure and cardiovascular disease. It is also a powerful predictor of diabetes. Studies have shown that a high distribution of fat around the abdomen is related to problems with the use of insulin. Even for people with a normal BMI, a high waist circumference can increase the risk of diabetes.
Measuring waist circumference is more straightforward for most people than calculating BMI, and requires fewer resources. To measure waist circumference, a person loops a tape measure around the abdomen halfway between the last rib and the top of the hip bone, at the level of the navel, taking care to remove excess clothing and measure as close to the skin as possible. Although different ethnic groups have different accepted values, and more research is needed to establish the exact relationships between those values and a person’s risk of diabetes, the measurement is very revealing nevertheless.
As part of World Diabetes Day, an annual global awareness event started in 1991 by the International Diabetes Federation (IDF) and the World Health Organization (WHO), the IDF has produced and distributed measuring tapes that incorporate the guidelines for understanding waist circumference results. This simple tool, called the Blue Circle Test, will help individuals understand how waist circumference is associated with diabetes risk and take action toward reducing that risk. “This initiative, used in combination with assessments of all potential risk factors, will allow people around the world to learn if they are at risk of type 2 diabetes and start taking control of their lifestyle,” says IDF President Jean Claude Mbanya.
No single measurement can determine a person’s risk of type 2 diabetes, but a large number of factors that contribute to that risk are directly related to a person’s lifestyle, history, and family background. Better knowledge of these risks and the ways to mitigate them can help prevent new cases of the growing diabetes epidemic.