The Korean Diabetes Association recently published “Diabetes Fact Sheet in Korea, 2020,” (2020 DFS), which investigated the number of diabetic patients and management status in adults aged 30 or more in Korea.

The 2020 fact sheet found that 72 percent of diabetic patients had hypercholesterolemia. This signals that it is important to manage LDL-C (low-density lipoprotein cholesterol) according to guidelines for preventing serious complications such as cardio-cerebrovascular disease in diabetic patients.

Korea Biomedical Review met with Mok Ji-o, director of public relations at the KDA, to learn the current status of diabetic patients’ management of comorbid diseases and the KDA’s stance on the LDL-C treatment goal. Mok is a professor of internal medicine at Soonchunhyang University Bucheon Hospital.

Question: The KDA has been publishing Diabetes Fact Sheet every year since 2012. What is the purpose of the publication, and what effects do you expect?

Answer: Using Korea’s representative data, our society provides accurate statistics on the prevalence of diabetes, comorbidities, and management status in Korea to clinicians, researchers, national healthcare policymakers, and media experts.

We hope to provide useful information to help clinicians treat patients. Also, we want to help researchers conduct basic studies and policymakers to establish healthcare policies. Based on accurate information on the current state of diabetes, we want to know what kind of efforts are needed for improvement and expect to do so.

Q: What was notable in the 2020 fact sheet?

A: The prevalence of diabetes was still at a high level of 14 percent, rather than in a continuous increase, and fasting blood sugar disorders have increased. Although the glycated hemoglobin control rate was still low, it was steadily improving a little by a little.

This year’s fact sheet was most different from previous ones in that it defined hypercholesterolemia as LDL-C at 100 mg/dl or higher. In the past, the disease was based on total cholesterol of 240 mg/dl or more. When applying the LCL-C 100 standard, over 72 percent of patients with diabetes accompanied hypercholesterolemia.

This year’s fact sheet calculated the percentage of diabetic patients with both hypertension and hypercholesterolemia. The results showed that in adults over 30 years old, 43.7 percent accompanied all three diseases – diabetes, hypertension, and hypercholesterolemia. In those aged 65 or more, 51.4 percent had the three simultaneously.

Q: Is there any particular reason for changing the definition of hypercholesterolemia from the one based on the total cholesterol level to another based on LDL-C?

A: Diabetic patients have a two to four times higher risk of death from cardiovascular disease than non-diabetic people. So, diabetic patients with hypercholesterolemia are the target of aggressive treatment.

The U.K. Prospective Diabetes Study (UKPDS) found that LDL-C was the most powerful predictor of coronary artery disease in patients with type-2 diabetes among various risk factors for cardiovascular disease. It is a well-known fact that LDL-C should be lowered to reduce the risk of cardiovascular disease.

An increase in LCL-C by 39 mg/dL raises the risk of coronary artery disease by about 60 percent.

As the criteria for hypercholesterolemia was changed from 240 mg/dl of total cholesterol to 100 mg/dl of LDL-C, the prevalence of the disease also changed. In the latest analysis, the prevalence of hypercholesterolemia was 42.4 percent in diabetic people aged 30 or more when measured by total cholesterol. However, using LDL-C, the number went up to 72 percent. There was a nearly 30 percentage point difference between the two.

Q: Does this mean that diabetic patients are almost always hypercholesterolemia patients?

A: Three major comorbidities among diabetic patients are obesity, hypertension, and hypercholesterolemia. Among the three, with the LDL-C 100 mg/dL standard, hypercholesterolemia's accompanying rate is the highest. In fact, in diabetic patients, we say the patient has hypercholesterolemia if the patient’s LDL-C is 100mg/dL or higher, HDL-C is 40-50 mg/dL or lower, or triglyceride is 150 mg/dL or higher.

If we apply the criteria, over 90 percent of diabetic patients accompany hypercholesterolemia, according to the Korean Society of Lipid and Atherosclerosis. Using LDL-C only made the percentage record at 72 percent. Therefore, we say most diabetic patients accompany hypercholesterolemia. The American Diabetes Association guidelines state that anyone with diabetes between the ages of 45 and 75 is required to receive moderate or intense statin treatment regardless of LDL-C levels.

Q: Then, what is the appropriate treatment goal for hypercholesterolemia in diabetic patients?

A: Generally, the lower the LDL-C level, the better. According to our society’s standard, we recommend lowering LDL-C to less than 100 mg/dL for diabetic patients without cardiovascular disease.

Recent meta-analyses showed that the lower LDL-C, the better in people who have risk factors without cardiovascular disease. Therefore, we recommend that diabetic patients with albuminuria and chronic kidney disease or a family history of early onset of hypertension, smoking-related disease, or coronary artery disease should lower the LDL-C target below 70 mg/dL.

Also, in a study of patients with an acute coronary syndrome or a history of cardiovascular disease, using high-dose statins to reduce LDL-C to less than 70 mg/dL significantly lowered cardiovascular disease risk. So, we recommend controlling LDL-C below 70 mg/dL for diabetic patients accompanying cardiovascular disease.

Q: What is the current status of lipid management, including LDL-C among diabetic patients in Korea?

A: The fact sheet in 2018, analyzing data of the public from 2013 to 2016, showed that only 50 percent of diabetic patients aged 30 or more controlled LDL-C below 100 mg/dL.

The 2020 DFS showed that the proportion improved to 55.3 percent.

This rate is improving every year because the KDA is aggressively promoting the importance of lipid management.

Q: It seems that the three underlying diseases -- hypertension, diabetes, and dyslipidemia – should be managed in an integrated manner rather than separately. What’s your opinion on this?

A: I agree 100 percent. All the diabetes fact sheet, the hypertension fact sheet, and the dyslipidemia fact sheet investigated the three diseases' comorbidity rates. The three diseases are the most important risk factors for cardiovascular disease, and they occur together very often. If they are accompanied, the risk of cardiovascular disease is much higher. So, it is crucial to control them in an integrated manner.

Only 11.5 percent of diabetic patients achieved the three goals together -- glycated hemoglobin at below 6.2 percent, blood pressure lower than 140/85, and LDL-C below 100.

In each disease, about half of diabetic patients are successfully controlling the number. But the integrated control rate is very low. So, we are emphasizing the importance of integrated management in the treatment guidelines.