Generalizability of Clinical Trials Supporting the 2017 American College of Cardiology/American Heart Association Blood Pressure Guideline

Abstract

This study uses National Health and Nutrition Examination Survey data to evaluate whether patients enrolled in the clinical trials that support the American College of Cardiology/American Heart Association (ACC/AHA) guideline are representative of the US adult population recommended additional pharmacotherapy by the ACC/AHA guideline.

Figure 1.. Flowchart of SPRINT and ACCORD Eligibility Criteria Applied to Adult NHANES Participants

ACC/AHA indicates American College of Cardiology/American Heart Association; ACCORD, Action to Control Cardiovascular Risk in Diabetes trial; BMI, body mass index (calculated as weight in kilograms divided by height in meters squared); BP, blood pressure; DBP, diastolic blood pressure; HDL, high-density lipoprotein cholesterol; LDL, low-density lipoprotein cholesterol; eGFR, estimated glomerular filtration rate; NHANES, National Health and Nutrition Examination Survey; SBP, systolic blood pressure; SPRINT, Systolic Blood Pressure Intervention Trial; ULN, upper limit of normal. SI conversion factors: To convert HDL and LDL to mmol/L, divide by 0.0259; creatinine to µmol/L, multiply by 88.4. Trial eligibility was determined in NHANES participants without and with diabetes using the published inclusion and exclusion criteria from the SPRINT and ACCORD trials, respectively.^, While both trials excluded individuals with factors likely to limit medication adherence, only SPRINT specified what these factors might include; thus, SPRINT exclusions were applied to both populations. ^aThe 2017 ACC/AHA guideline defines hypertension based on the average of 2 BP readings of 130/80 mm Hg or higher on 2 separate occasions. In NHANES, BP was measured as the mean of 3 measurements obtained at 1-minute intervals during a single medical evaluation. ^bDiabetes was defined by self-reported history or a hemoglobin A_1c as 6.5% or higher (to convert to proportion of total hemoglobin, multiply by 0.01). ^cLife expectancy less than 3 years is estimated based on Lee Index score of 14 or higher because a score of 14 is associated with a median predicted life expectancy of 3.1 years. ^dAnimal fluency test score less than 15. The animal fluency test examines categorical verbal fluency and scores have been shown to discriminate between persons with normal cognitive functioning compared with those with mild cognitive impairment and more severe forms of cognitive impairment, such as Alzheimer disease.

Figure 2.. Representativeness of the Systolic Blood Pressure Intervention Trial and Action to Control Cardiovascular Risk in Diabetes Trial in US Adults Recommended Additional Antihypertensive Pharmacologic Treatment by the ACC/AHA Guideline

The 2017 American College of Cardiology/American Heart Association (ACC/AHA) guideline defines hypertension based on blood pressure (BP) level above 130/80 mm Hg. The ACC/AHA guideline recommends pharmacologic therapy to all patients whose BP level is greater than 140/90 mm Hg and to patients whose BP level is between 130-139/80-89 mm Hg if they have a history of diabetes, are older than 65 years, or have a 10-year cardiovascular disease risk of more than 10% by pooled cohort risk equations. National Health and Nutrition Examination Survey analysis includes individuals with BP level higher than 130/80 mm Hg and those reporting use of BP medications regardless of measured BP. Individuals classified as recommended additional antihypertensive pharmacologic treatment include those not previously taking any antihypertensives and those currently taking antihypertensives but above ACC/AHA guideline goal.