Change in Troponin I Levels With Intensive Blood Pressure Control

Cardiac troponin (cTn) is a group of myocardial injury biomarkers used for diagnosing and prognosticating myocardial infarction. 1–3 Among the cTn subtypes, cTnI elevation is specific for myocardial damage, while cTnT elevation occurs in other conditions such as skeletal myopathies. 1–3 A previous study showed that cTnT levels increased with intensive systolic blood pressure (SBP) lowering in hypertensive individuals at 1 year, and a longitudinal increase in cTnT was associated with a higher risk of cardiovascular disease (CVD). 4 However, similar data on cTnI, a specific biomarker of myocardial injury, are lacking. This post-hoc analysis of the SPRINT (Systolic Blood Pressure Intervention Trial) aimed to assess the change in cTnI with intensive blood pressure (BP) control and the prognostic value of longitudinal changes in cTnI at 1 year for incident CVD. Publicly available SPRINT data on the NHLBI BioLINCC was used for this study. Details of the SPRINT have been previously described. 4 hs-cTnI was measured on the Abbott i2000SR Immunochemistry Analyzer at Baylor College of Medicine using stored plasma samples collected at randomization and 1 year. The change in cTnI at 1 year was used to stratify the study population into ≥50% decrease, ≥50% increase, or unchanged (<50% change). 4 Change in cTnI was calculated by subtracting log e (cTnI randomization ) from log e (cTnI 1-year ). The primary outcome was