Results from a large population-based study involving patients with type 2 diabetes (T2D) indicated that achieving a greater number of “ABC” targets (HbA1c, blood pressure, and LDL-cholesterol) incrementally reduced the risk of cardiovascular disease (CVD) in this patient population. However, not all ABC risk factors were of equal importance in CVD risk reduction .
For the great majority of patients with T2D around the world, maintaining optimal levels of all three ABC risk factors, as recommended by the American Diabetes Association, has been very challenging. Researchers from the Department of Family Medicine and Primary Care at the University of Hong Kong conducted a study to understand the relative effect of these factors individually, or in combination, in the prevention of CVD .
Via examining patient records at 74 outpatient primary care clinics in Hong Kong area, the investigators identified more than 144,000 adult T2D patients who were receiving health services for T2D. The patients were followed up from the first time having their ABC values recorded until the date of occurrence of a CVD event, death, or the last date of the study, whichever occurred first.
The investigators found that achieving more ABC targets incrementally reduced the incidence of total CVD and individual disease, including coronary heart disease, stroke, and heart failure. Those who achieved optimal levels of all three targets (HbA1c < 7%, blood pressure < 130/90 mm Hg, and LDL-C < 2.6 mmol/L) reduced their CVD risk by 55%. However, only 9% of patients achieved all these three targets. Among those achieving only 1 ABC target, LDL-C reduction was associated with the greatest CVD risk reduction (42%), followed by blood pressure reduction (18%), and HbA1c reduction (13%). Subgroup analysis showed that patients with duration of T2D less than 1 year benefited the most from achieving the ABC targets, suggesting the importance of intervention in early disease stage.
Although the sample size of this study was very large, the investigators acknowledged that the cohort only comprised Chinese patients from one geographic region. As important, the effect of lifestyle factors such as diet and exercise was not assessed in this study.
The study results published in The Journal of American Heart Association (August 2017).
Why is this Clinically Relavant?
- Achieving all three ABC targets led to the greatest CVD risk reduction in patients with T2D
- However, throughout the world, only a small proportion of patients are able to achieve all three ABC targets
- For example, another publication notes that only 14.3% of patients in the U.S. and 12% of patients in Canada were able to achieve three-factor control 
- For T2D patients who are unable to tolerate treatments to improve all three ABC factors due to increased adverse effects, excessive polypharmacy, cost, or treatment burden, clinicians should consider prioritizing efforts on treatment of LDL-C, followed by blood pressure and HbA1c
- Prevention of CVD among patients with T2D is most effective earlier in the disease
 Wan, E.Y.F., et al., Effect of Multifactorial Treatment Targets and Relative Importance of Hemoglobin A1c, Blood Pressure, and Low-Density Lipoprotein-Cholesterol on Cardiovascular Diseases in Chinese Primary Care Patients With Type 2 Diabetes Mellitus: A Population-Based Retrospective Cohort Study. J Am Heart Assoc, 2017. 6(8).
 Ali, M.K., K.M. Bullard, and E.W. Gregg, Achievement of goals in U.S. Diabetes Care, 1999-2010. N Engl J Med, 2013. 369(3): p. 287-8.