Exercise as it relates to Disease/General vs Vigorous Lifestyle Advice: The effects on the risk of diabetes

This is a review of the journal article "The Finnish Diabetes Prevention Study (DPS)" by Lindström, Louheranta, Mannelin, Rastas, Salminen, Eriksson, Uusitupa & Tuomilehto (2003).

What is the background to this research?

Perhaps the greatest cause for concern from a health perspective in western society is the increasing number of overweight and obese individuals. Being overweight or obese greatly increases the likelihood of developing chronic health conditions such as heart disease, liver disease and diabetes. It has been shown by the World Health Organisation (WHO) that 1 in 3 adults aged over 18 world wide are considered overweight and 1 in 10 are considered obese. It was also shown that one of the leading causes of death world wide is diabetes, which was directly responsible for 1.5 million deaths in 2012.

Approximately 1.7 million Australians have diabetes, this includes both diagnosed (1.2 million known and registered) and undiagnosed (approximately 500,000). 280 Australians develop diabetes everyday, that is one person every five minutes. The total annual cost of diabetes in Australia is estimated to be $14.6 billion.

Diabetes Australia defines type 2 diabetes as "a progressive condition in which the body becomes resistant to the normal effects of insulin andor gradually loses the capacity to produce enough insulin in the pancreas". Type 2 diabetes accounts for 85-90% of all diabetes cases and usually occurs in middle-aged adults over the age of 45, however it can also be diagnosed in younger age groups too. There is no direct cause of Type 2 diabetes, however the likelihood of development increases with lifestyle risk factors such as high blood pressure, obesity, physical inactivity and a poor diet; Type 2 diabetes can also develop due to a family history of the condition and is even more likely to develop within certain ethnic groups.

The Finnish Diabetes Prevention Study (DPS) was one of the first controlled, randomised studies to show that type 2 diabetes is preventable with a lifestyle intervention. The study was established with the goal of studying the short- and long-term effects of a controlled and intensive lifestyle intervention on glucose and lipid metabolism.

Where is the research from?

A study group of Lindström, Louheranta, Mannelin, Rastas, Salminen, Eriksson, Uusitupa & Tuomilehto from Finland. This was a multi-centre study which took place in the Finnish cities of Helsinki, Kuopio, Turku, Tampere and Oulu. This study was approved by the ethics committee of the National Public Health Institute in Helsinki, Finland.

What kind of research was this?

This was a controlled, randomised study with quantitative measures spanning over a three year period.

What did the research involve?

522 middle-aged, overweight participants with an impaired glucose tolerance were identified through means of local advertisements for the study or via previous epidemiological survey results. The population were randomised into either a usual care group or an intensive lifestyle intervention group. The usual care group received general advice about lifestyle and diabetes risk which was delivered either individually or in one group session, some printed material was also provided. The intensive lifestyle intervention group received seven face-to-face dietary consultation sessions with the study nutritionist over the three year research period, during these consultations the participants also received individual guides to increasing their overall physical activity which was highlighted by the study physician upon each annual visit.

What were the basic results?

Lindström, Louheranta, Mannelin, Rastas, Salminen, Eriksson, Uusitupa & Tuomilehto found that the intervention group showed a significantly greater improvement in their goals when compared to the control group. After one and three years the intervention group showed 4.5 kg and 3.5 kg weight reductions, while the control group showed 1.0 kg and 0.9 kg weight reductions respectively. The intervention group also showed more improved measures of glycemia and lipemia than those of the control group. The risk of developing diabetes was reduced by 58% in the intervention group compared to the control group.

What conclusions can we take from this research?

The intensive lifestyle intervention posed as the most effective long-term method of reducing the risk of developing diabetes by encouraging participants to make beneficial changes in diet, physical activity and both clinical and biochemical parameters of reduced risk of diabetes. This study shows that an intensive lifestyle intervention is a practical method of reducing the risk of developing type 2 diabetes.

Practical advice

While genes play a large role in the susceptibility of developing type 2 diabetes, overweight and obese individuals also have a higher risk of developing the chronic disease than a healthier population does. Through the conclusions drawn from The Finnish Diabetes Study it is recommended to those who are overweight or obese to implement a similar lifestyle intervention. While the intensive lifestyle intervention which was administered in the study itself is not very cost-effective as it required its participants to liaise with a staff of health professionals on a regular basis, it showed the greatest health improvements for the test subjects. However, that is not to say that the control group's (who still received health guidance from professionals but in moderation) intervention was ineffective as participants in this group still showed health improvements, only less extensive than those of the intensive intervention group. Meeting with general practitioners and local community groups run by a health professional, while less intensive, is a cost-effective manner in which to become healthier and reduce the risks of developing diabetes.

Further information/resources

For further information on the benefits on health interventions to help prevent and lower the risk of developing type 2 diabetes, follow the links below.

• Preventing diabetes: http://www.cdc.gov/diabetes/basics/prevention.html
• 10 tips to help prevent type 2 diabetes: https://www.betterhealth.vic.gov.au/health/tentips/10-tips-to-help-prevent-type-2-diabetes
• Diabetes and physical activity: https://www.niddk.nih.gov/health-information/diabetes/diabetes-physical-activity
• Diet, nutrition and the prevention of chronic diseases: http://www.who.int/dietphysicalactivity/publications/trs916/summary/en/