Menopausal hormone therapy and central nervous system tumors: Danish nested case-control study

Area of Science:

• Neuro-oncology
• Endocrinology
• Epidemiology

Background:

• Estrogen-based menopausal hormone therapy (MHT) impacts central nervous system (CNS) tumor risk.
• The specific role of the progestin component in MHT and its differential effects based on treatment regimen (continuous vs. cyclic) on CNS tumor risk remain unclear.

Purpose of the Study:

• To investigate the association between menopausal hormone therapy (MHT) use, specifically the progestin component and treatment regimens, and the risk of developing meningioma and glioma.
• To differentiate the risk associated with continuous versus cyclic estrogen-progestin therapy and progestin-only therapy.

Main Methods:

• A nested case-control study was conducted within a nationwide cohort of 789,901 Danish women aged 50-60 years, followed for 19 years (2000-2018).
• Prescription data was used to assess cumulative exposure to MHT. Statistical analyses accounted for covariates like educational level and use of other medications.
• The study identified 1,595 meningioma and 1,167 glioma diagnoses during follow-up.

Main Results:

• Both estrogen-progestin and progestin-only MHT were associated with an increased risk of meningioma.
• Continuous estrogen-progestin therapy showed a higher risk of meningioma (HR 1.34) compared to cyclic therapy (HR 1.13).
• Progestin-only therapy was linked to increased meningioma risk and potentially glioma risk, with current/recent use showing the highest hazard ratios.

Conclusions:

• Continuous estrogen-progestin use is associated with an elevated risk of meningioma, while cyclic use was not significantly associated.
• No increased glioma risk was observed with estrogen-progestin use.
• Progestin-only therapy demonstrated an association with increased meningioma risk and a potential increase in glioma risk, necessitating further research into long-term effects.