Optimal timing of dopamine agonist withdrawal in patients with hyperprolactinemia: a systematic review and meta-analysis

Purpose Dopamine agonists (DAs) are recommended as first-line treatment for patients with hyperprolactinemia. Generally, it is accepted that patients with hyperprolactinemia do not need lifelong medication, but the optimal timing for DA withdrawal has not been determined. The aim of this systematic review and meta-analysis is to assess the impact of DA withdrawal on the clinical outcomes of patients with hyperprolactinemia, and to explore possible factors affecting successful DA withdrawal. Methods The databases of PubMed, Cochrane and EMBASE were searched up to May 2016. Results The proportion of patients with persisting normoprolactinemia after DA withdrawal reached 36.6% in a random effects model (95% CI, 29.4-44.2%; I-squared: 82.5%). Data of stratified analysis showed that the success rate of drug withdrawal was high in patients using cabergoline (CAB) as the only treatment (41.2%; 95% CI 32.3-50.4%) and those using CAB over 24 months (48.7%; 95% CI 38.9-58.5%), especially in patients with idiopathic hyperprolactinemia (73.2%; 95% CI 55.6-87.7%). In addition, patients who received a low maintenance dose of CAB, and had a significant reduction in tumor size (over 50%) before withdrawal, were more likely to achieve success (51.5 and 49.4%, respectively). Conclusion The success rate of DA withdrawal has increased in recent years. Further, the success rate of CAB withdrawal was higher than that of bromocriptine, especially in patients with a duration of treatment longer than 24 months. Conclusively, the probability of success was higher in patients who received low-dose CAB maintenance treatment and those who achieved a significant reduction in tumor size before withdrawal.