Outcomes of hyperbolic tapering of antidepressants.

Background: In patients attempting to discontinue their antidepressant medication, there have been no prospective studies on patterns of withdrawal as a function of the rate of antidepressant reduction during the tapering trajectory, and moderators thereof.

Objective: To investigate withdrawal as a function of gradual dose reduction.

Design: Prospective cohort study.

Methods: The sampling frame consisted of 3956 individuals in the Netherlands who received an antidepressant tapering strip between 19 May 2019 and 22 March 2022 in routine clinical practice. Of these, 608 patients, majorly with previous unsuccessful attempts to stop, provided daily ratings of withdrawal in the context of reducing their antidepressant medications (mostly venlafaxine or paroxetine), using hyperbolic tapering strips offering daily tiny reductions in dose.

Results: Withdrawal in daily-step hyperbolic tapering trajectories was limited, and inverse to the rate of taper. Female sex, younger age, presence of one or more risk factors and faster rate of reduction over shorter tapering trajectories were associated with more withdrawal and differential course over time. Thus, sex and age differences were less marked early in the course of the trajectory, whereas differences associated with risk factors and shorter trajectories tended to peak early in the trajectory. There was evidence that tapering in weekly larger steps (mean per-week dose reduction: 33.4% of previous dose), in comparison with daily tiny steps (mean per-day dose reduction: 4.5% of previous dose or 25.3% per week), was associated with more withdrawal in trajectories of 1, 2 or 3 months, particularly for paroxetine and the group of other (non-paroxetine, non-venlafaxine) antidepressants.

Conclusion: Antidepressant hyperbolic tapering is associated with limited, rate-dependent withdrawal that is inverse to the rate of taper. The demonstration of multiple demographic, risk and complex temporal moderators in time series of withdrawal data indicates that antidepressant tapering in clinical practice requires a personalised process of shared decision making over the entire course of the tapering period.