Metabolic Syndrome (or "Syndrome X")

What is Metabolic Syndrome?

The metabolic syndrome is a cluster of risk factors that increases the risk of coronary heart disease and type two diabetes. It is characterised by raised fasting plasma glucose, low HDL (protective/good) cholesterol, high LDL (poor) cholesterol, raised triglycerides, abdominal obesity and high blood pressure.

Current estimates suggest around 20-25% of the worlds population have the metabolic syndrome (1). Those who have the metabolic syndrome are twice as likely to die from and three times as likely to have a heart attack or stroke compared to non metabolic syndrome sufferers(1). Additionally those with metabolic syndrome are five times more likely to develop type two diabetes at some point in their life (1,3). Current Australian estimates produced by the 2005 AusDiab study state that 1.7 million Australians have diabetes, but nearly half of all cases of type two diabetes remain undiagnosed (2). Approximately 275 Australians develop diabetes every day (2). Diabetes is the fastest growing chronic disease in Australia and one of the most common world wide and is the fourth leading cause of death in the developed world 1,4).

This cluster of cardiovascular disease (CVD) risk factors that represents metabolic syndrome is expected to create a tsunami of heart disease and stroke cases creating a CVD epidemic of biblical proportions.

The Link: Diabetes and Metabolic Syndrome

Globally 3.2 million people die from complications associated with diabetes (1). Type two diabetes accounts for 90% of all cases of diabetes and has total financial cost of 10.3 billion dollars (2). Type two diabetes is a leading cause of premature death and illness due to it’s association with CVD, and is now responsible for up to 80% of all CVD deaths (1,2,3). 

The metabolic syndrome and its cluster of risk factors is most commonly experienced is those who are suffering from glucose intolerance or type two diabetes. This factor leads to substantial disease burden due to the additional cardiovascular disease risk of the metabolic syndrome, which has been suggested to be beyond the risk of each abnormality (1,3,4).

The metabolic syndrome is not however just limited to those suffering form diabetes and impaired glucose  tolerance. In fact many individuals experiencing the first signs of metabolic syndrome do so well before any formal diagnosis of type two diabetes has been made. These initial signs are represented by a elevated blood glucose (hyperglycemia) and triglyceride level and a decreased HDL (protective/good) cholesterol. These factors in there own right significantly increase an individuals risk of CVD. In fact those individuals with either or both type two diabetes or metabolic syndrome have the same CVD risk as a current cigarette smoker.

What Causes Metabolic Syndrome

What causes metabolic syndrome is a hotly debated topic amongst experts however most would agree that central obesity and insulin resistance are significant factors (1,3,4). Additional factors that may also have a casual effect include genetics, physical inactivity, poor nutritional status, ageing, a pro inflammatory state and hormonal changes (1). The role of these aspects do however appear to be greatly influenced by the ethnic origin of the individual (1).

1. Insulin Resistance

The pancreas's beta cells are responsible for the bodies production of the vital hormone insulin. Insulin is the key hormone responsible for driving glucose into the bodies cells to be utilised as a source of fuel. Insulin resistance occurs when cells in the liver, skeletal muscle and adipose/fat tissue become less sensitive and eventually resistant to insulin (1,3,4).  As a consequence glucose remains in the blood stream as it is no longer being taken up by the cells. This leads to further production of insulin (hyperinsulinlaemia)  in order to remove the high levels of blood glucose, which over time weakens the beta cells of the pancreas and eventually leads to beta cell failure (1). If the pancreas can no longer produce insulin then a person’s ability to control their blood sugar is lost which subsequently leads to a diagnosis of type two diabetes. Prior to this occurring the body is already in a pro inflammatory state and an accumulation of triglycerides has begun to occur. This leads to cellular damage and is characterized in it’s early stages by low HDL (good) cholesterol, high triglycerides,  high alanine transaminase (liver function test) , increased waist circumference and potentially raised serum uric acid levels.

2. Central Obesity

Many experts believe that central obesity is the catalyst to metabolic syndrome and insulin resistance (1,3,4,5). Obesity is an important independent CVD risk factor that is routinely associated with high cholesterol levels, high blood pressure, raised blood sugar and low HDL (good) cholesterol. Research indicates that obesity is associated not only with an increased risk CVD but also type two diabetes, some forms of cancer and osteoarthritis. Obesity is internationally recognized as a body mass index of equal to or greater than 30kg/m2. However, more indicative of metabolic syndrome is an individuals waist circumference or the accumulation of fat around the abdomen (1).  

Criteria of Metabolic Syndrome in Adults

The International Diabetes Federation Definition

International Diabetes Federation”: Worldwide Definition of the Metabolic Syndrome. www.idf.org/idf-worldwide-definition-metabolic-syndrome

Ethnic specific values for waist circumference

How is it diagnosed?

General investigation should include blood tests of cholesterol and lipids, blood sugar, liver function and kidney function (these tests require you have to have been fasting overnight). Analysis of the urine and a urine albumin to creatinine ratio (looking for protein in the urine as a sign of kidney damage).

Ways to reduce your risk.

Incorporate as many lifestyle changes as you can. Eating a healthy diet, exercising regularly, and losing weight will all dramatically reduce your risk of diseases associated with Metabolic syndrome.

Make dietary changes. Eat plenty of natural wholegrain foods, vegetables and fruit,  reduce portion sizes and limit foods high in sugar and fat. Reduce saturated foods such as meat, full cream dairy and many processed foods. This will help improve your cholesterol levels. Reducing alcohol consumption to less than 2 standards drinks a day may help lower triglyceride levels.

Increase your physical activity level- regular exercise raises the level of HDL (‘good’) cholesterol in the blood, which helps remove excess cholesterol from your body and protects against heart disease. Exercised muscle cells are also more sensitive to insulin.

Manage your weight– increasing physical activity and improving eating habits will help you lose excess body fat. As a result, your blood pressure will drop and your cells will be more sensitive to insulin.

Quit smoking– smoking increases your risk of heart disease, stroke, cancer and lung disease. Quitting will have many health benefits, especially if you have Metabolic syndrome.

Medication may be required– Lifestyle changes are extremely important but sometimes medication may be required to manage the condition. The most     important thing is to reduce your risk of heart disease, stroke and Type 2 diabetes.

How will it affect me?

Metabolic syndrome can present with a variety of symptoms depending on the associated medical  conditions. Some people with Metabolic Syndrome may not have any symptoms initially. You may experience the following symptoms:

· Tiredness and fatigue.

· Sleep apnoea (transient periods of breathing sensation and snoring during sleep) associated with obesity.

· Headache (due to high blood pressure)

· Frequent urination, thirst, weight loss or gain due to high blood sugars.

· Chest pain or shortness of breath on exertion  (i.e. poor blood supply to the heart).

· Collapse or other neurological symptoms due to blockage of the vessels that supply the brain with blood.

Where do I get help?

· Your doctor.

· An accredited practicing dietician (contact the dieticians Association of Australia: http://www.daa.asn.au)

· International Diabetes Institute. (03) 9258 5000.

· Diabetes Australia (www.diabetesqld.org.au) 1300 136 588

· Quitline (137 848) www.quit.org.au

References

1.)“International Diabetes Federation”: Worldwide Definition of the Metabolic Syndrome. www.idf.org/metabolic-syndrome

2)”Diabetes Australia”. www.diabetesaustralia.com.au.

3)“National Heart, Lung and Blood Institute”. www.nhlbi.nih.gov/health/dci/Diseases/ms/ms_whatis.html

4)“Mainstreaming the Metabolic Syndrome: a definitive definition”.www.mja.com.au/public/issues/183_04_150805/zim10442_fm.html

5)“Metabolic Syndrome”. www.heart.org/HEARTORG

For More Information

Wesley Corporate Health

Level 2 / 46 Edward Street

Brisbane  Qld  4000

Phone:  07 3234 2600

Email: wellness@weshealth.com.au

Disclaimer

This Fact Sheet is provided for your information only and does not replace qualified medical advice. The information provided may not apply to every person or all situations. A medical practitioner should be consulted for all treatment and medication.