Low Free Testosterone Is Independently Associated With Long-Term Mortality in Men With Chronic Spinal Cord Injury

Area of Science:

• Endocrinology
• Neurology
• Gerontology

Background:

• Testosterone deficiency is common in men with chronic spinal cord injury (SCI).
• Low testosterone is linked to obesity, sarcopenia, inflammation, and metabolic issues in SCI.
• The independent impact of low testosterone on long-term mortality in SCI is not well understood.

Purpose of the Study:

• To determine if baseline calculated free testosterone (cFT) independently predicts all-cause mortality in men with chronic SCI.
• To evaluate cFT as a prognostic biomarker in this population.

Main Methods:

• Retrospective cohort study of 152 men with chronic SCI.
• Follow-up until death or December 2024 (median 62 months).
• Cox proportional hazards models used to assess testosterone's association with mortality, with adjustments for age, comorbidities, inflammation, BMI, and albumin.

Main Results:

• Twenty-four deaths (15.8%) occurred during follow-up.
• Lower baseline cFT was significantly associated with increased mortality (HR 0.97 per pg/mL increase; p=0.0139).
• A cFT threshold of 59.55 pg/mL identified significantly lower survival (log-rank p < 0.0001).

Conclusions:

• Low calculated free testosterone (cFT) is an independent predictor of all-cause mortality in men with chronic SCI.
• cFT may serve as an integrative biomarker of systemic frailty in SCI patients.
• Further validation in prospective multicenter studies is warranted.