Context: Dopamine agonists are the treatment of choice for prolactinomas and symptomatic idiopathic hyperprolactinemia. However, the optimal treatment strategy and treatment duration is not clear in all details.
Objective: The aim of the study was to assess the effect of dopamine agonist withdrawal in patients with idiopathic hyperprolactinemia and prolactinomas.
Data sources: PubMed, the Cochrane Library, the Web of Science, and EMBASE were searched electronically. No restriction was made with respect to language.
Study selection: Studies reporting the proportion of normoprolactinemic patients after withdrawal of dopamine agonist or studies in which this proportion could be calculated were eligible. Both observational studies and clinical trials were eligible. Nineteen studies were included in the meta-analysis, with a total of 743 patients.
Data extraction: Data extraction was performed by two reviewers independently.
Data synthesis: The pooled proportion of patients with persisting normoprolactinemia after dopamine agonist withdrawal was 21% in a random effects model [95% confidence interval (CI), 14-30%; I(2) 81%). Stratified analysis showed higher proportions of treatment success in idiopathic hyperprolactinemia (32%; 95% CI, 5-80%), compared with both microprolactinomas (21%; 95% CI, 10-37%), and macroprolactinomas (16%; 95% CI, 6-36%). In a random effects meta-regression adjusting for cause of hyperprolactinemia, a longer treatment duration was associated with treatment success (P = 0.015), whereas the use of cabergoline showed a trend of effect (P = 0.07).
Conclusions: This meta-analysis showed that hyperprolactinemia will recur after dopamine agonist withdrawal in a considerable proportion of patients. The probability of treatment success was highest when cabergoline was used for at least 2 yr.