A Preliminary Study for INFORMED

Description

This is an unblinded NIH Stage I of Behavioral Intervention Development trial, using serial multiple-period single participant crossover design. Investigators will enroll 20 participants, conducting an N-of-1 trial in each. The intervention is a two-arm crossover withdrawal/reversal design (On [A] vs. Off [B]) with up to 6 periods, each period lasting up to 6 weeks. The sequence of treatment will be randomized to either ABAB or BABA. Each participant will have the option to participate in additional (no more than 6) periods if they wish to gather more data. The intervention drug will be beta-blockers, previously prescribed to the participants by their physician. The investigators have developed a titration algorithm, where during the On period (A), participants will be on their baseline beta-blocker dose (or the highest dose they can safely tolerate). During the Off period (B), their beta-blockers will be down-titrated and subsequently discontinued (or at the lowest dose they can safely tolerate); we will decrease the dose of the beta-blocker by 50% every week regardless of which beta-blocker they are on. When returning to On, from Off, we will up-titrate by 50% until reaching their home dose (or the highest dose they can safely tolerate).