Low serum testosterone is associated with an increased risk of first-time renal calculi in men without testosterone replacement therapy.

Low testosterone was associated with a higher risk of one or more kidney stone encounter diagnoses in men aged 18 and older.

• Hazard ratio of 1.12 (95% CI [1.09-1.15]) for men aged ≥18 with low testosterone (<300 ng/dL) compared to normal testosterone (≥300 ng/dL)
• Study used the TriNetX Research Network in a retrospective cohort design
• Men were excluded if they had a history of kidney stone encounter diagnosis before testosterone measurement or a history of testosterone therapy prescription at any point
• Propensity score matching was employed with an absolute standardized mean difference of less than 0.1 used as an indicator of successful matching

No significant association between low testosterone and kidney stone encounter diagnoses was observed in men aged 18-24.

• Hazard ratio of 1.09 (95% CI [0.85-1.39]) for the 18-24 age group, which was not statistically significant
• The confidence interval crosses 1.0, indicating no significant risk elevation in this youngest age subgroup
• The increased risk appears to begin in men aged 25 based on age-stratified analysis

The highest risk of kidney stone diagnosis associated with low testosterone was observed in men aged 34-44.

• Hazard ratio of 1.29 (95% CI [1.17-1.38]) for men aged 34-44 with low testosterone
• The abstract also references men aged 33-44 as having the highest observed risk, suggesting the peak risk window is approximately the mid-30s to mid-40s
• Risk stratification by age subgroups revealed a gradient of association across age groups

The study was designed to evaluate kidney stone risk in men based on total testosterone level using a large retrospective network database.

• Men aged ≥18 were divided into a low testosterone cohort (<300 ng/dL) and a normal testosterone cohort (≥300 ng/dL)
• The TriNetX Research Network was used as the data source
• The main outcome of interest was risk of developing an initial kidney stone in men aged ≥18 and within age-based subgroups
• Exclusion criteria included prior kidney stone encounter diagnosis before testosterone measurement and any history of testosterone therapy prescription

The study was conducted against a background of concurrent increasing incidence of low serum testosterone and increasing prevalence of kidney stones in men.

• The incidence of low serum testosterone has been increasing in men of all ages
• The period of increasing low testosterone corresponds to an increasing prevalence of kidney stones
• The relationship between testosterone and kidney stones was described as currently unclear at the time of the study