Diabetes screening tests may be inaccurate, and can lead to over and under treatment.
Current screen and treat strategies for diabetes prevention may be ineffective for a majority of patients at risk of developing the disease.
The screen and treat prevention method involves determining whether an individual is at risk of developing diabetes. If a patient is classified as high risk, they are offered interventions to prevent disease progression.
Another approach used is to target the entire population through public health policies, campaigns, and other educational initiatives. This type of program would reach individuals regardless of their risk level.
The UK’s National Diabetes Prevention Programme, along with initiatives in the United States and Australia, focus on the screen and treat method. However, findings from a new study published byThe BMJ, suggest that this method is only partially effective.
The study authors discovered that this approach is only successful if there is a test that can accurately assess whether a patient is high-risk, and if there is an intervention that is accepted by both physicians and patients. For maximum efficacy, the test should exclude low-risk patients who do not require intervention.
In the study, the investigators evaluated the accuracy of current diagnostic tests that screen for pre-diabetes, which may progress into type 2 diabetes if left untreated. They also assessed the efficacy of certain interventions in preventing diabetes onset in patients with pre-diabetes, according to the study.
In total, the researchers evaluated 49 studies of screening tests, and 50 clinical trials of the interventions. Screening tests included fasting plasma glucose, and raised HbA1c, and interventions included changing lifestyle, or metformin drug therapy. Lifestyle changes may include healthier eating habits and increasing physical activity levels.
The investigators discovered that the accuracy of the pre-diabetes screening tests were low. They found that fasting glucose is specific, but not sensitive, while HbA1c tests are neither sensitive nor specific, according to the study.
These findings suggest that a large portion of individuals are receiving unnecessary treatment or are not receiving the necessary treatment based on which test was used.
Lifestyle changes that were in place for 3 to 6 years reduced the risk of developing type 2 diabetes by 37%, which translates to only 151 of 1000 individuals developing the disease, compared with 239 of 1000 control group patients, according to the study. After follow-up, the risk only decreased 20%.
Metformin treatment was seen to reduce the risk of developing diabetes by 26%, which translated to 218 of 1000 individuals developing diabetes, compared with 295 of 1000 not taking the drug.
The authors concluded that the current screen and treat method may not be effective for all high-risk patients, and should be used in conjunction with public health campaigns and other policies to ensure individuals are educated about diabetes and prevention.