Christianne Roumie, MD, on Intensive SBP Control and Diabetes Incidence

Intensive systolic blood pressure (SBP) treatment is likely not associated with increased diabetes, but may be associated with more impaired fasting glucose, according to new findings published in Hypertension.

Researchers arrived at their conclusion in a new analysis of data from The Systolic Blood Pressure Intervention Trial (SPRINT). In the present analysis, the researchers compared the impact of intensive blood pressure (BP) treatment (defined as an SBP of less than 120 mm Hg) with that of standard treatment (less than 140 mm Hg). Participants included in the study were aged 50 years or older, had an SBP of 130 to 180 mm Hg, and had increased cardiovascular risk.

The study’s main outcome was incident diabetes, defined as a fasting blood glucose ≥126 mg/dL, self-reported diabetes, or new use of hypoglycemic agents. The secondary outcome was impaired fasting glucose (defined as 100 to 125 mg/dL) among participants with normoglycemia (defined as less than 100 mg/dL).

A total of 299 (2.3% per year) incident diabetes events occurred among 4187 participants in the intensive treatment group compared with 251 events (1.9% per year) in the standard treatment group. These translated to rates of 22.6 vs 19.0 events per 1000 person-years of treatment, respectively, with an adjusted hazard ratio (HR) of 1.19. For impaired fasting glucose, the rates were 26.4 vs 22.5 per 100 person-years in the intensive and standard treatment groups, respectively (adjusted HR 1.17).

“The risks and benefits of intensive blood pressure targets should be factored into individualized patient treatment goals,” the authors of the study wrote.

Endocrinology Consultant spoke with study author Christianne Roumie, MD, MPH, associate professor of Internal Medicine and Pediatrics at Vanderbilt University Medical Center, and physician in the Veterans Affairs Tennessee Valley Healthcare System in Nashville, Tennessee.

Endocrinology Consultant: What prompted you to assess whether intensive systolic blood pressure (SBP) control was associated with the incidence of diabetes in patients with elevated cardiovascular risk and an SBP of 130 to 180 mmHg?

Dr Roumie: The SPRINT Randomized Trial provided a nice opportunity to evaluate the relationship between intensive BP control and the development of diabetes. There are prior observational studies that found a relationship between higher BPs and the development of new onset diabetes, but in most of those studies, patients did not have a high risk of CVD. The SPRINT Trial started with a high cardiovascular risk population who were free of diabetes at the time of enrollment and randomization. Those patients were randomly assigned to either intensive BP control with a systolic goal of less than 120 mmHg, or standard blood pressure goal (or systolic of less than 140 mmHg). All patients were followed from randomization for a median of about 3 years for the development of diabetes.

Endocrinology Consultant: The results of your analysis indicated that intensive SBP control was not associated with increased diabetes, but was associated with more impaired fasting glucose in this patient population. How does this finding inform clinical practice?

Dr Roumie: Impaired fasting glucose is defined as a fasting blood sugar between 100 and 125 mg/dL. This was a very common occurrence among participants in both study arms. Impaired fasting glucose occurred in 16% of patients in the standard arm and 18% of patients in the intensive arm. The clinical significance of this elevated blood sugar should be considered along with the main SPRINT Trial findings of reductions in cardiovascular outcomes and death.

Endocrinology Consultant: What does this study suggest about the benefits and risks of intensive SBP control in patients with elevated cardiovascular risk, as well as the importance of individualized treatment?

Dr Roumie: Practically, this suggests that individualized treatment goals need to be pursued for most patients based on their risk for diabetes, the possible benefits of the reduced cardiovascular risk, and additional consideration of their antihypertensive medication burden. 

Endocrinology Consultant: What key takeaways do you hope to leave with health care clinicians reading this piece?

Dr Roumie: The main SPRINT findings were terminated early due to overwhelming evidence of benefit. There was a statistically and clinically significant reduction in cardiovascular events with intensive BP control. The risk of impaired fasting glucose was also more common among those in the intensive group but was small when compared to the beneficial effects on mortality.

Endocrinology Consultant: What is the next step for future research?

Dr Roumie: There remains a complex relationship between the medications used to treat hypertension and the risk of diabetes development. Future work will examine if the medications used for hypertension treatment had a protective or harmful association with diabetes.

—Christina Vogt

Reference:
Roumie CL, Hung AM, Russell GB, et al. Blood pressure control and the association with diabetes mellitus incidence: Results from SPRINT Randomized Trial. Hypertension. 2020;75(2):331-338. https://doi.org/10.1161/HYPERTENSIONAHA.118.12572.