Diabetics with lower achieved SBP may be at greater risk for cardiovascular disease

A new study from Hong Kong found adults with type 2 diabetes and hypertension who achieved a systolic blood pressure (SBP) of less than 130 mmHg did not experience a reduction in cardiovascular risk, compared to patients with SBPs between 130 and 140 mm Hg.The study’s findings were published in Diabetes Care.

“Our findings imply that achieved SBP measurements of less than 120 mmHg or less than 130 mmHg may not be associated with reductions in cardiovascular disease (CVD) risk and may even potentially be associated with an increased risk of CVD and mortality when compared with an achieved SBP less than 140 mmHg,” wrote lead author Eric Yuk Fai Wan, PhD candidate, of the University of Hong Kong. “These findings support the argument to raise SBP treatment targets from less than 130 to less than 140 mmHg as recommended by a number of diabetes management guidelines, including the American Diabetes Association.”

The researchers sought to compare the incidence of CVD among patients with type 2 diabetes, with treated hypertension, who had achieved systolic blood pressure (SBP) of less than 120, 130 and 140 mmHg, after an increase in their antihypertensive medications.

They found diabetic patients who achieved a SBP of less than 120 mmHg were associated with a higher risk of CVD compared with diabetic patients who achieved a SBP of less than 130 mmHg and less than 140 mmHg.

The cohort consisted of 28,000 primary care patients who were recruited between January 2009 and December 2011 in outpatient clinics of the Hong Kong Hospital Authority. The cohort was further stratified into three achieved SBP groups: 2,079 individuals were in the 120 mmHg group, 10,851 were in the 130 mmHg group and 15,084 were in the 140 mmHg group.

After an average follow up time of almost five years, the researchers found the incidence of CVD in the diabetic cohort were 318 (15 percent), 992 (9 percent) and 1,635 (approximately 11 percent) for patients with systolic blood pressure readings of less than 120, 130 and 140 mmHg, respectively.

The authors noted no reduction in CVD risk was observed between the achieved SBP of less than 130 mmHg and less than 140 mmHg among adults older than 65. They added there may be some benefit from achieving a SBP reading of less than 130 mmHg in patients less than the age of 65. In short, according to the results of this particular study, tighter SPB targets are more applicable to younger patients.

“From our findings, younger patients, on the other hand, may benefit from more stringent SBP targets (less than 130 mmHg),” the researchers concluded. “There is a lack of research exploring SBP targets in younger patients, but the International Society of Hypertension does suggest that SBP targets of less than 130 mmHg can be considered and may be appropriate in younger patients as they might be able to achieve lower SBP targets with fewer adverse effects.”