Approximately 1 in 10 people will develop diabetes at some point in their life: it affects an estimated 415 million people worldwide, with 46% living with the condition unaware of it. It’s a widely heard of condition but one that is generally poorly understood and a condition that can have devastating complications or even be fatal if not looked after properly.
Around 90% of cases of diabetes in the UK are ‘type two’ diabetes, linked to a number of lifestyle (and some genetic) factors including obesity, dietary intake of saturated fats and refined sugars and a lack of sleep, and whilst the majority of type two diabetes diagnoses are in adults, there is a trend of younger patients being diagnosed with type two as a result of the global obesity epidemic. In type two diabetes, insulin is still produced by the body, but is insufficient in quantity or ineffective in operation, as such many people with type two diabetes can be treated with diet and exercise alone, or in combination with tablets that alter the way in which the body recognises insulin.
The remaining 10% is largely taken by ‘type one’ diabetes, also known as ‘young onset’ diabetes, which is typically diagnosed in people under the age of 14, and is the result of the bodies’ immune system destroying insulin producing cells (the Beta cells of the Islets of Langerhans in the pancreas), as a result people with type one diabetes require insulin from artificial sources in order to maintain blood glucose levels. Other types of diabetes include gestational diabetes, a usually transient condition which affects a woman during pregnancy, cystic fibrosis related diabetes and steroid diabetes brought about by high doses of glucocorticoids.
As one of the earliest characterised diseases, with the symptoms having been described around 1500 BC, by an Egyptian doctor, treatment for those with diabetes has come a long way, although it was not until the work of Banting and Best in the early 1920s that insulin was first isolated as an effective treatment for type one diabetes.
Initial treatment with insulin provided near immediate relief to two symptoms of diabetes in a 14 year old boy on a Canadian hospital ward in 1922 (most children developing diabetes in the early 1900s would quickly suffer its fatal consequences), which was followed quickly by six other patients who all experienced an increased quality of life, and a prolonged lifespan. Eli Lilly a pharmaceutical company still involved in insulin production today, began mass producing insulin shortly after and by 1923, 25,000 patients were being treated across North America. The dramatic pace at which the prospects of people who had diabetes rapidly improved hasn’t slowed much since then, indeed even within the last ten years, diabetes treatments have changed beyond much recognition.
For a long time, insulin was administered by nurses using large, often painful syringes, and the only way to test ‘blood’ sugar levels at home was with a urine test; it wasn’t until 1981 that blood glucose meters started being marketed for ‘consumer ’ use, which provided a much more rapid turnaround in reading sugar levels, allowing for people with diabetes to exercise a much greater level of control over their blood sugars. Of course, with time improvements have been made to these sensors allowing for the time taken for a reading to become known falling from two minutes to a matter of mere seconds.
A further innovation in the field of treating diabetes was the advent of the insulin pump, which has come a long way since the first model in 1963 which was worn as a backpack. The first insulin pumps endorsed for use in the UK were approved in 2003. Newer pumps allow for continuous doses of rapid acting insulin to be given, mimicking the way in which the pancreas gives a supply of basal (or background) insulin, regulating blood glucose between meal times, and larger bolus doses taken at meal times. Pumps offer a significant increase in the flexibility in diabetes care, and as such an increase in the quality of life for users.
In 2014 a new type of blood glucose monitoring system was announced – described as a ‘flash monitoring system’ the Freestyle Libre requires users to wear a small ‘patch’, roughly the same dimensions as a £2 coin, and allows for blood glucose readings to be delivered by near field communication (NFC: the same technology that allows contactless credit cards to work) within less than a second. This device also allows for users to see the last eight hours of blood sugars, and the direction the blood glucose level is heading in, providing invaluable insight for treating diabetes, especially in patients whose blood glucose is rapidly varying or who struggle to control blood glucose overnight. The device works by measuring glucose levels in the interstitial fluid, which surrounds tissue cells, using a small plastic sensor (about the thickness of a hair, and 5 mm long) inserted into the upper arm.
Whilst any potential cure for diabetes is still seemingly a long way off, hopes for an ‘artificial pancreas’ are closer to being realised. This system would involve ‘closing the loop’, that is, the removal of the need for human intervention in the treatment of diabetes, which in theory, and with good algorithm programming could lead to perfect control, mimicking that of a person who doesn’t have diabetes. Initial testing on closed loop systems have featured a continuous blood glucose monitor, not unlike that of the Libre, and a pump that ‘talk’ to each other.
Some of the first clinical trials into such a system are currently underway in France, with a long-term glucose sensor being implanted into a vein in the neck that connects to the heart. A wire under the skin then connects the sensor to the insulin pump, which is implanted into the body. The trials have shown promise but also limitations, which highlights the unpredictability of the condition, even when being controlled automatically by technology. The sensor obtained accurate measurements of blood glucose over 95% of the time, and managed to maintain blood glucose levels in the target range (4.0-7.0 mmol/L) for more than 50% of the time. Episodes of low blood sugar (hypoglycaemia) dropped to less than 5% of the pre- trial incident rates. However, the ideal system would avoid these hypos altogether as well as eliminating any time spent outside of the ‘normal’ range, although it is hoped that this will come with improvements to the system and the mathematical algorithms that calculate the volume of insulin required throughout the day.
Whilst this system is far from a cure and would still require system maintenance and upgrades every nine months or so, it would undoubtedly lead to an increase in the quality of life of the user. Considering the vast increases in the treatment quality available to people with diabetes in the last ten years, it does not seem to be unimaginable that a closed loop system will be available within the next ten years.