Blood pressure (BP) control can reduce the risk of stroke among diabetic patients; however, it is not known whether the lowest risk of stroke is among diabetic patients with the lowest BP level.Objective:
Our objective was to investigate the race-specific association of different levels of BP with stroke risk among diabetic patients in the Louisiana State University Hospital-based longitudinal study.Design, Setting, and Participants:
We prospectively investigated the race-specific association of different levels of BP at baseline and during an average of 6.7 years of follow-up with incident stroke risk among 17 536 African American and 12 618 white diabetic patients within the Louisiana State University Hospital System.Main Outcome Measure:
We evaluated incident stroke until May 31, 2012.Results:
During follow-up, 2949 incident cases of stroke were identified. The multivariable-adjusted hazard ratios of stroke associated with different levels of systolic/diastolic BP at baseline (<110/65, 110–119/65–69, 120–129/70–80 [reference group], 130–139/80–90, 140–159/90–100, and ≥160/100 mm Hg) were 1.88 (95% confidence interval = 1.38–2.56), 1.05 (0.80–1.42), 1.00, 1.05 (0.86–1.27), 1.12 (0.94–1.34), and 1.47 (1.24–1.75) for African American diabetic patients and 1.42 (1.06–1.91), 1.22 (0.95–1.57), 1.00, 0.88 (0.72–1.06), 1.02 (0.86–1.21), and 1.28 (1.07–1.54) for white diabetic patients, respectively. A U-shaped association of isolated systolic or diastolic BP at baseline and during follow-up with stroke risk was observed among both African American and white diabetic patients. The U-shaped association was confirmed in both patients who were and were not taking antihypertensive drugs.Conclusions:
The current study suggests a U-shaped association between BP and the risk of stroke. Aggressive BP control (<110/65 mm Hg) and high BP (≥160/100 mm Hg) are associated with an increased risk of stroke among both African American and white patients with type 2 diabetes.