Aggressive lowering of blood pressure may be associated with increased risk of coronary heart disease (CHD) in black or white patients with diabetes, according to research published online May 20 in Diabetes Care.
Wenhui Zhao, M.D., Ph.D., of the Pennington Biomedical Research Center in Baton Rouge, La., and colleagues conducted a prospective cohort study from 2000 to 2009 involving 17,536 African-American and 12,618 Caucasian patientswith diabetes. The association of blood pressure with CHD risk was analyzed.
The researchers identified 7,620 cases of incident CHD at a mean follow-up of 6.0 years. After adjustment for multiple variables, the hazard ratios of CHD associated with BP at baseline in blacks with diabetes were 1.73 for <110/65 mm Hg, 1.16 for 110-119/65-69 mm Hg, 1.04 for 120-129/70-80 mm Hg, 1.00 for 130-139/80-90 mm Hg, 1.06 for 140-159/90-100 mm Hg, and 1.11 for ≥160/100 mm Hg; the multivariable-adjusted hazard ratios of CHD at these baseline BP levels in whites with diabetes were 1.60, 1.27, 1.08, 1.00, 0.95 and 0.99, respectively. A U-shaped association of CHD risk with isolated systolic and diastolic blood pressure at baseline, and blood pressure during follow-up, was found in both black and white patients with diabetes. In patients with diabetes who were aged 60 years or older, this association between BP and CHD risk changed to an inverse relationship.
“In summary, in this large hospital-based cohort study, we found that aggressiveblood pressure control (i.e., systolic BP <120 mm Hg or diastolic BP <70 mm Hg) is associated with an increased risk of CHD among both African-American and white diabetic patients with type 2 diabetes,” the authors write. “Furthermore, for the elder group, the harm is even higher.”