Individualizing treatment choices in the systolic blood pressure intervention trial.

BACKGROUND: Any treatment decision should be tailored to the individual patients' characteristics. A personalized approach aims to help better selecting the patients who are likely to benefit most from a treatment decision. In the systolic blood pressure intervention trial, intensive treatment reduced the rate of major cardiovascular events, but increased the rate of serious adverse events (SAEs).

OBJECTIVES: To assess the trade-off between efficacy and safety to simultaneously quantify an individual patient's absolute benefit and absolute harm, helping clinicians making better therapeutic choices in daily practice.

METHODS: Multivariable Poisson regression models were used to identify independent risk factors for: primary composite cardiovascular outcome and major SAEs = safety. Estimates from the models were used to quantify each individual risk.

RESULTS: Subclinical cardiovascular disease, number of antihypertensive agents, current smoking, age, urine albumin-to-creatinine ratio, and serum creatinine were associated with increased risk of both primary outcome events and SAEs. Triglycerides were associated with increased primary outcome events only, and chronic kidney disease and female sex with SAEs only. The models were well calibrated and showed good performance (c-index for safety = 0.69 and c-index for efficacy = 0.72). For the primary outcome, there is a steep gradient in risk by fifths of the predicted model and a similar gradient exists for the safety outcome predicted model. Mortality within 1 year of an efficacy outcome (as assessed by the Kaplan-Meier method) was nearly three-fold higher than following a safety outcome (21.9 vs. 7.5%). If one judges the clinical importance of efficacy and safety outcomes based on their 1-year mortality, then there is a net benefit of intensive therapy for almost all patients.

CONCLUSION: Antihypertensive treatment intensification is associated with lower cardiovascular event rates; however, it increases the risk of adverse events. However, having adverse events has less weight when it comes to therapeutic decisions and antihypertensive therapy intensification is beneficial for the great majority of patients included in the systolic blood pressure intervention trial.