Podcast Summary
Episode Overview
Podcast: AACE Podcasts
Episode 68: Impulse Control Disorders in Patients with Hyperprolactinemia on Dopamine Agonist Therapy
Date: September 29, 2025
Host: Dr. Elizabeth (Lisa) Bauer
Guest: Dr. Nicholas Tritos, Pituitary Endocrinologist, Massachusetts General Hospital
Theme:
This episode provides a comprehensive exploration of impulse control disorders (ICDs) in patients with hyperprolactinemia who are treated with dopamine agonists. Dr. Bauer interviews Dr. Tritos, the lead author of a recent review on this under-recognized topic, to unpack the clinical manifestations, risk factors, biology, screening strategies, real-world management, and the state of scientific understanding about ICDs in this context.
Key Discussion Points and Insights
1. Why Focus on ICDs in Hyperprolactinemia?
- Limited Attention in Literature: ICDs in hyperprolactinemia patients on dopamine agonists have been under-discussed in endocrinology compared to their recognition in Parkinson’s disease.
- Raising Awareness: Dr. Tritos highlights the sensitive nature of ICDs as a possible reason for underreporting by both patients and clinicians.
"This topic has received relatively limited attention in the endocrine literature." — Dr. Tritos (01:22)
2. Hyperprolactinemia & Dopamine Agonist Therapy—A Primer
- Definition & Causes: Hyperprolactinemia is high serum prolactin, with causes ranging from pituitary adenomas to medications and systemic diseases.
- Therapeutic Rationale: Dopamine agonists (mainly cabergoline, less so bromocriptine) are the first-line treatments due to efficacy and tolerability.
"Dopamine agonists are generally first line therapy ... and can improve gonadal function and fertility in addition to reducing the size of the tumor." — Dr. Tritos (04:28)
3. What Are Impulse Control Disorders?
- Definition & Manifestations: ICDs are behaviors stemming from inability to resist urges—examples include pathological gambling, compulsive shopping, hypersexuality, compulsive eating, and, more rarely, kleptomania or pyromania.
- Clinical Impact: ICDs can cause significant distress and harm to patients and their families.
"These are behaviors resulting from an inability to resist temptations or urges in a given individual. ... Some examples may include pathological gambling, compulsive shopping, hypersexuality ..." — Dr. Tritos (05:05)
4. Prevalence and Underdiagnosis
- Wide Reported Range: Studies show ICDs may affect 7.5% to 46% of patients on dopamine agonists—a variance attributed to study methods, population differences, and likely underreporting.
"This could depend on a variety of factors, including the test instruments ... but also potentially differences between study populations." — Dr. Tritos (06:57)
5. Risk Factors for Developing ICDs
- Age and Sex: Younger age and male sex are more commonly associated with higher ICD risk, with some nuance (e.g., women may have higher risk of compulsive shopping/eating in certain reports).
- Genetic Susceptibility: Emerging evidence links genetic polymorphisms in dopamine, serotonin, and other neurotransmitter systems to risk, though findings are preliminary.
"Younger age has been associated with a higher risk of impulse control disorders in general, and also male sex ..." — Dr. Tritos (07:37)
6. The Pathobiology—Why Does This Happen?
- Neurobiological Theory: Overactivation of the mesocorticolimbic dopamine system (the reward pathway) by dopamine agonists may override inhibitory controls, increasing impulsivity.
"Activation of dopamine receptors ... may result in decreased inhibitory responses to external cues in some patients." — Dr. Tritos (09:23)
7. Drug-Specific Considerations
- Cabergoline vs. Bromocriptine: No solid evidence that one drug carries greater ICD risk; cabergoline may simply be prescribed more often.
- Dose & Duration: No clear connection between ICD emergence and dopamine agonist dose or treatment duration; cases can arise months to years after starting therapy.
"There has been no evident association between treatment duration or even the dose ... and the risk of developing impulse control disorders." — Dr. Tritos (11:26)
8. Clinical Management and Monitoring
- Proactive Screening: Patient education is key. Family involvement often helps identify uncharacteristic compulsive behavior early.
- Screening Tools: The QUIP-RS (Questionnaire for Impulsive-Compulsive Disorders in Parkinson’s Disease - Rating Scale) is favored—it is brief, free, and easily self-administered. No tools are currently validated specifically for hyperprolactinemia.
"The one that personally I like using more often is the QUIP rs ... The patient can quickly fill out this instrument within maybe five minutes or so." — Dr. Tritos (15:30)
- Baseline and Follow-Up: Ideal to obtain baseline screening and continue at each visit, regardless of duration on therapy.
"I think it's prudent to screen patients at each clinic visit, including patients who have been on therapy for a number of years ..." — Dr. Tritos (17:31)
9. Patient Counseling—How to Approach the Conversation
- Straightforward Discussion: Clinicians should inform patients and families about the rare but serious risk of ICDs, listing examples and encouraging prompt disclosure of changes in behavior.
"There are occasionally people who may develop irresistible urge to do certain things ... I would ask patients to report any unusual behaviors that are new and uncharacteristic of them." — Dr. Tritos (19:02)
10. If an ICD Develops—What Next?
- Primary Step: Stop the dopamine agonist if possible—generally leads to ICD resolution within ~3 months.
- Alternatives and Support: In milder cases, consider dose reduction; for serious behaviors, discontinuation is recommended. Consider multidisciplinary, psychiatric input, especially when alternative prolactinoma treatments (like surgery or radiation) are necessary.
"I would rather stop the medication and then pursue alternatives." — Dr. Tritos (20:35)
- Role of Psych Interventions: Limited evidence on SSRIs or CBT; more research needed.
"Psychiatric consultation. Certainly one should have a low threshold to request ... There's very limited data about use of pharmacotherapy, such as SRI's or cognitive behavior therapy in these cases." — Dr. Tritos (22:50)
11. Research Gaps and Future Directions
- Prediction Models Needed: Prospective studies and multi-omic approaches could help identify at-risk patients and inform prevention/mitigation.
- Validation of Screening Tools: Need for ICD tools specifically validated for hyperprolactinemia populations.
- Data on Behavioral/Psych Interventions: More studies needed to evaluate non-pharmacological treatment efficacy.
"Understanding the pathophysiology better ... can also lead potentially to preventive strategies that can work." — Dr. Tritos (25:15)
Notable Quotes & Memorable Moments
On raising awareness
- "I think that raising awareness of the issue among clinicians and their patients can have a very positive impact on patient care." — Dr. Tritos (01:22)
On the hidden burden of ICDs
- "If you don't look for it, you may not find it. It doesn't mean it's not there." — Dr. Bauer (27:51)
On clinical vigilance
- "This issue serves as a lesson and the reminder that even typically well tolerated medications can have potentially serious adverse effects. And that to me highlights the importance that clinicians have to be vigilant at all times to assure patient safety." — Dr. Tritos (26:59)
Timestamps for Key Segments
- Introduction & Motivation — 00:28–02:00
- Basics of Hyperprolactinemia & Treatments — 03:00–04:49
- What are ICDs? — 05:05–05:47
- Prevalence & Under-reporting — 06:42–06:57
- Risk Factors — 07:31–09:03
- Biological Mechanisms — 09:03–10:10
- Drug Risk & Duration — 10:10–12:10
- Detection, Screening Tools, & Family Involvement — 13:33–15:30
- Counseling Patients — 18:44–19:02
- Management of ICDs — 20:11–22:30
- Role of Psychiatry & Alternatives — 22:30–24:22
- Research Gaps — 25:09–26:26
- Main Takeaway Messages — 26:51–27:51
Final Takeaways
- ICDs are an under-recognized but significant risk for patients with hyperprolactinemia on dopamine agonists.
- Proactive, candid communication and systematic monitoring (including use of brief, accessible screening tools like the QUIP-RS) make all the difference.
- If problematic ICDs occur, stopping the dopamine agonist typically resolves symptoms within several months—but clinicians must be prepared to arrange alternative management where needed.
- Continued research is needed to refine risk prediction, screening, and management strategies.