Effects of Intensive Systolic Blood Pressure Control on All-Cause Hospitalizations

Abstract

Intensive blood pressure control decreases the rate of cardiovascular events by >25% compared with standard blood pressure control. We sought to determine whether the decrease in cardiovascular events seen with intensive blood pressure control is associated with an increased rate of other causes of hospitalization. This is a post hoc analysis of SPRINT (Systolic Blood Pressure Intervention Trial) in 9361 adult participants with hypertension and elevated cardiovascular risk. Participants were randomly assigned to an intensive or standard systolic blood pressure goal (<120 or <140 mm Hg, respectively). The primary outcome was hospitalization rates per 100 person-years for hospitalizations not associated with SPRINT primary events. After excluding hospitalizations linked to SPRINT primary events, there were 4678 participants with a rate of 19.70 hospitalizations per 100 person-years, compared with 4683 participants with a rate of 19.65 (P=0.37). Equivalence testing shows that these hospitalization rates were statistically equivalent at the P=0.05 level. Of those with hospitalizations, >1 hospitalization was seen in 38.8% of intensive arm participants and 41.9% of standard arm participants (P=0.08). The mean cumulative count of nonprimary event hospitalizations was comparable between the two arms. The most common causes of hospitalization were cardiovascular (23.6%) followed by injuries, including bone and joint therapeutic procedures (15.7%), infections (12.0%), and nervous systems disorders (10.7%). No categories of hospitalization were statistically more common in the intensive arm compared with the standard arm. Thus, the decrease in cardiovascular events seen with intensive blood pressure control is not associated with an increased rate of other causes of hospitalization. Registration- URL: https://www.clinicaltrials.gov; Unique identifier: NCT01206062.

Keywords: cardiovascular diseases; goals; hospitalization; hypertension; risk factors.

Figures

Figure 1 -

CONSORT diagram. Abbreviation: BP = blood pressure

Figure 2 -

Estimated mean count of hospitalizations using the mean cumulative count method. Using the method of mean cumulative count (ref), the estimated mean number of hospitalizations on the y-axis, with days in study on the x-axis is displayed. The mean count and 95% confidence interval appears in red for the intensive arm, and in blue for the standard arm. This method takes into account the competing risks of death, primary events, and prior hospitalizations.