What is the relationship between low testosterone (Low T) and Benign Prostatic Hyperplasia (BPH)?

Relationship Between Low Testosterone and Benign Prostatic Hyperplasia (BPH)

Contrary to traditional beliefs, low testosterone (Low T) is likely a risk factor for BPH rather than high testosterone, with evidence suggesting that hypogonadism may contribute to prostatic inflammation and BPH development. 1, 2

Pathophysiological Relationship

• BPH develops due to an imbalance between cellular growth and apoptosis in the prostatic transition zone, with hormonal factors playing a significant role 3
• The traditional view that high testosterone causes BPH has been challenged by recent evidence suggesting that low testosterone may actually contribute to BPH development 2
• Inflammation is a key aspect of BPH development, and low testosterone (rather than high) may promote prostatic inflammation 2
• The prevalence of low testosterone in men with LUTS/BPH is surprisingly high - approximately 25.7% in a large clinical trial, with even higher rates (39.3%) among obese men 4

Clinical Evidence

• Multiple studies have failed to demonstrate exacerbation of voiding symptoms attributable to BPH during testosterone supplementation therapy 5
• A 2022 randomized clinical trial showed that 24 weeks of testosterone therapy in testosterone-deficient men with BPH improved ultrasound, molecular, and histological markers of prostate inflammation 6
• While prostate volume increases slightly during testosterone replacement therapy (mainly during the first six months), this does not typically translate to worsened urinary symptoms 5
• The poor correlation between prostate volume and urinary symptoms explains why testosterone replacement doesn't typically worsen LUTS despite modest increases in prostate size 5

Metabolic Connections

• Low testosterone frequently occurs in metabolic syndrome, which is also associated with BPH 2
• Metabolic factors like dyslipidemia can trigger prostate inflammation, contributing to BPH development 2
• The combination of low testosterone and hyperestrogenism (common in metabolic syndrome) may create a hormonal environment that favors prostatic inflammation 2

Clinical Implications

• Physicians should be alert to the possibility of hypogonadism in men with LUTS/BPH, particularly in those who are obese 4
• Testosterone replacement therapy does not appear to worsen LUTS in men with BPH and may actually improve markers of prostate inflammation 6, 1
• BPH can occur even in men with low testosterone levels because the high levels of 5α-reductase and dihydrotestosterone (DHT) in the prostate allow for prostatic hyperplasia development despite low circulating testosterone 7
• Individual men with hypogonadism may occasionally experience increased voiding symptoms with testosterone replacement therapy, so monitoring is still important 5

Monitoring Recommendations

• During testosterone replacement therapy, prostate volume should be monitored, particularly during the first six months when most changes occur 5
• Urine flow rates, post-void residual volumes, and prostate symptoms should be assessed to detect any individual variations in response 5
• Regular monitoring is recommended for men with risk factors for BPH progression, regardless of testosterone status 3