Post-market Review Products Used in the Management of Diabetes Report to Government Stage 2: Insulin Pumps February 2015

1.3 Context for the Diabetes Post-market Review

1.3.1 Post-market monitoring

Post-market reviews are a systematic and formal approach to monitoring the use of medicines listed on the Pharmaceutical Benefits Scheme (PBS). The Post-market Review Programme was established to improve patient safety and quality use of medicines, in addition to supporting the ongoing evidence-based cost and clinically effective use of PBS listed medicines.

The Post-market Review Programme aims to achieve four main goals:

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  improved patient safety through better understanding of adverse events and medicine-related harms;
  
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  ensuring the ongoing viability of the PBS through better targeting of medicines use and avoiding preventable wastage or inappropriate prescribing;
  
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  developing a better understanding of medicines use, to validate intended clinical benefit and inform medicines evaluation processes; and
  
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  strengthened medicines pricing management, including through better management of clinical and economic uncertainty.
  

A full post-market review will only proceed following Ministerial approval.

Part 2 - Diabetes mellitus: treatment and access to insulin pumps

2.1 Diabetes mellitus

Diabetes mellitus (diabetes) is a chronic disease characterised by high levels of glucose in the blood. Insulin, a hormone produced by the beta-cells of the pancreas, controls blood glucose levels. Diabetes occurs when the pancreas is unable to produce enough insulin, or the body becomes resistant to insulin, or both (World Health Organization (WHO) 2013). There are three main types of diabetes: type 1 diabetes, type 2 diabetes, and gestational diabetes (WHO 2013).

2.1.1 Type 1 diabetes

Type 1 diabetes is an autoimmune disease characterised by the progressive destruction of the insulin producing beta-cells of the pancreas. People with type 1 diabetes cannot produce insulin and require lifelong insulin injections for survival (WHO 2013). Type 1 diabetes is sometimes referred to as juvenile onset diabetes or insulin dependent diabetes. Type 1 diabetes affects about 12% of people with diabetes (AIHW 2013a). The cause of type 1 diabetes is not known, there are no known cures, and it is not preventable with current knowledge (Misso 2010, WHO 2013).

2.1.2 Type 2 diabetes

People with type 2 diabetes produce insulin, but may not produce enough of it or cannot use it effectively (insulin resistance). It is associated with hereditary factors and lifestyle risk factors, including poor diet, insufficient physical activity and being overweight or obese (Shaw & Chisholm 2003). Some people with type 2 diabetes may be able to manage their condition through lifestyle changes, others may require diabetes medications or insulin injections to control blood glucose levels. Type 2 diabetes occurs mostly in people aged over 40 years. However, the disease is becoming increasingly prevalent in younger age groups, including children (WHO 2013).

2.1.3 Gestational diabetes

Gestational diabetes occurs during pregnancy and usually resolves after birth. However, a history of gestational diabetes increases a woman's risk of developing type 2 diabetes later in life. It is estimated that gestational diabetes affects women in about 3-8% of pregnancies. Additionally, certain populations including Aboriginal or Torres Strait Islander, Indian, Vietnamese, Chinese, Middle Eastern and Polynesian, are at increased risk of gestational diabetes (Diabetes Australia 2012).

2.2 Prevalence of diabetes in Australia

Diabetes mellitus was endorsed as a National Health Priority Area at the Australian Health Minister's Conference in 1996, in recognition of the high prevalence of the disease in Australia, its impact on morbidity and mortality, and its potential for health improvements through prevention and treatment programmes.

According to the Australian Health Survey: Updated Results (2011-12), the total number of people in Australia aged 2 years and older that have ever been diagnosed with diabetes (excluding gestational diabetes) is 999,000, around 4.6% of the population (Australian Bureau of Statistics (ABS) 2013).

The prevalence of diabetes in Australia has almost doubled since 1995 (407,900 people). This substantial increase has been attributed to more people developing the disease, but also people with diabetes living longer and improved detection of the disease. However, the prevalence of diabetes in terms of percentage of the Australian population, remained stable between 2007-08 and 2011-12 (4.5% in 2007–08) (ABS 2013).

The Australian Health Survey: Updated Results (2011-12) show that, of persons aged 2 years and older who reported having diabetes: 84.9% had type 2 diabetes, 11.9% had type 1 diabetes, and 3.3% had an unspecified type of diabetes. More men reported having diabetes than women (5.1% of all men compared with 4.2% of all women) (ABS 2013).

Type 1 diabetes can occur at any age, although new cases mostly occur in children and young adults. While many childhood diseases are declining in Australia, it is estimated that the prevalence of type 1 diabetes in the 0-14 year old demographic will increase by 10% between 2008 and 2013, from 5,700 to 6,300 (AIHW 2012a).

2.3 Complications

In type 1 diabetes, a lack of insulin elevates blood glucose levels (hyperglycaemia) and creates disturbances in carbohydrate, lipid and protein metabolism. Subsequently, because the body cells are not receiving a source of energy through glucose (sugar), the body responds by using fats as an energy source. This causes accumulation of ketones (an acidic molecule) in the blood, a by-product of abnormal lipid metabolism, lowering the blood pH to a point that is more acidic than normal and leading to diabetic ketoacidosis (DKA) (AIHW 2012b). If not treated, there are many potentially life threatening diabetes complications (Misso 2010).

For people with diabetes, low blood glucose levels (hypoglycaemia) can be brought on by delaying or missing a meal, eating an insufficient amount of carbohydrates, unplanned physical activity, alcohol consumption, and mismanagement of insulin administration or diabetes medicines. In the short-term, hypoglycaemia can lead to loss of coordination, slurred speech, confusion, loss of consciousness, seizure and death (Diabetes Australia 2010).

2.3.1 Long-term complications

As the disease progresses over time, diabetes macrovascular and microvascular complications can damage the heart, blood vessels, eyes, kidneys and nerves, as well as diminishing quality of life (WHO 2006). Diabetes increases the risk of:

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  heart disease and stroke;
  
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  diabetic neuropathy (nerve damage), and reduced blood flow and blood vessel damage, resulting in foot ulcers and limb amputation;
  
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  diabetic retinopathy, which can cause blindness resulting from long-term accumulated damage to the small blood vessels in the retina (microaneurysms);
  
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  nephropathy (kidney disease), which can lead to kidney failure; and
  
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  death.
  

After 15 years of having the disease, approximately 2% of people become blind and 10% develop severe visual impairment. Diabetes is one of the leading causes of kidney failure and this condition is the cause of death in 10-20% of people with diabetes. Diabetic neuropathy affects up to 50% of people with diabetes with common symptoms including tingling, pain, numbness, or weakness in the feet and hands (WHO 2013). Cardiovascular disease is the major cause of death in people with diabetes, accounting for approximately 50% of all fatalities (International Diabetes Federation 2011).

Early age of onset of type 1 diabetes is associated with a minor, but statistically significant reduction in IQ, presumably due to poor glycaemic control (Craig 2011). Serious complications of diabetes including nerve damage, foot ulcers, and eye and kidney disease, are already evident in some people aged 19-30 years; many of these conditions may have been preventable by improved glycaemic control (AIHW 2012a).

2.3.2 Diabetes-related deaths

In 2010, diabetes was associated with cause of death for nearly 7,750 people in Australia or 5.4% of all deaths that year (AIHW 2013b). However, these data may underestimate death caused by diabetes as it is not always recorded as a contributory cause on the death certificate (Yorkshire and Humbler Public Health Observatory 2008). Diabetes was the underlying cause of death in 88 people with type 1 diabetes aged 0-30 years in 200107 (AIHW 2012a).