Simultaneous Measurements of Follicle Stimulating Hormone and Total Testosterone and Associations in Clinically Localized Prostate Cancer

Are higher follicle-stimulating hormone levels before androgen deprivation therapy for prostate cancer associated with oncological and cardiac outcomes and overall survival?-a population-level analysis

Background

Androgen deprivation therapy (ADT), commonly delivered via a luteinizing hormone-releasing hormone (LHRH) agonist, is the standard treatment for advanced prostate cancer (PC). While quite effective, it has been associated with an increased risk of major adverse cardiovascular events (MACE). The exact mechanisms are not clear. However, it has been theorized that follicle-stimulating hormone (FSH), a pituitary hormone that is involved in controlling normal testosterone levels, which is decreased with LHRH-agonist therapy, may be the culprit. We performed a retrospective population-level study to test the link of FSH levels on the development of MACE, castrate-resistant PC (CRPC), and death among men starting ADT.

Methods

All men (n=1,539) who had an FSH level between 1999 and 2018 within 2 years prior to starting ADT and complete data were identified within the Veterans Affairs (VA) Health System. FSH was dichotomized as low/normal (≤8 IU/mL) and high (>8 IU/mL), using established cut-points. The associations between FSH and time to MACE, death, and CRPC were tested using log-rank tests and multivariable Cox proportional hazards models.

Results

Patients with high FSH were older (median 76 vs. 73 years, P<0.001), started ADT earlier (median 2007 vs. 2009, P=0.027), and had lower body mass index (BMI) (median 29.1 vs. 30.1 kg/m2, P=0.004) compared to those with low/normal FSH. On multivariable analysis, there was no association between FSH and time from ADT to MACE, CRPC, or death.

Conclusions

In this population-level study of men receiving an FSH test prior to starting ADT, there was no association between FSH levels and time from ADT to MACE, CRPC, or death. Although further studies are needed, these results do not support a link between pre-ADT FSH and long-term oncological or cardiovascular outcomes.

Are higher pre-diagnosis follicle stimulating hormone levels associated with long-term prostate cancer risk?

BACKGROUND

Follicle stimulating hormone (FSH) is a pituitary hormone that helps regulate testosterone homeostasis. Although it is generally accepted that FSH levels increase with LHRH-agonist therapy for prostate cancer (PC), the specific impact of FSH levels on risk of PC diagnosis is largely unknown. The objective of this study was to perform a population-level analysis to assess the association between FSH levels and PC diagnosis.

METHODS

All men (n = 386,018) who had a pre-PC diagnosis FSH level and complete data were identified within the Veterans Affairs Health System between 1999 and 2018. The association between FSH level and time from FSH test to PC diagnosis was tested using stratified Cox proportional hazards models. Multivariable models were adjusted for age, year, race, body mass index, and Charlson comorbidity index. Due to nonproportional hazards over time, time to PC was modeled separately: ≤4 years after an FSH test and >4 years following an FSH test.

RESULTS

Median age at first FSH level was 64 years (interquartile range [IQR]: 54-72), median year of FSH was 2010 (IQR: 2005-2014), and 70% of the cohort was white. Median follow-up was 76 months (IQR: 38-126) during which 17,519 men (4.5%) were diagnosed with PC. On multivariable analysis, in the first 4 years after FSH test, there was no association between FSH and time to PC diagnosis. Starting from 4 years after FSH test, on multivariable analysis, a higher FSH level was associated with lower risk of PC with continuous modeling, but found no association with log continuous and categorical modeling.

CONCLUSIONS

In this population-level study among male veterans receiving an FSH test for an unknown clinical indication, associations between FSH levels and PC risk were inconsistent and likely driven by selection bias and confounding variables. Future studies should consider different study designs.