What causes elevated testosterone levels in older men not on testosterone supplementation?

Causes of Elevated Testosterone in Older Men Not on Supplementation

Primary Pathological Causes

Elevated testosterone in older men not receiving supplementation is uncommon and warrants investigation for underlying pathological conditions, particularly testosterone-secreting tumors or exogenous androgen exposure.

Endogenous Overproduction

• Testosterone-secreting testicular tumors (Leydig cell tumors) can cause markedly elevated testosterone levels and should be evaluated with testicular ultrasound 1

• Adrenal tumors producing androgens may present with elevated testosterone and should be considered, particularly if DHEA-S is also elevated 1

• Acromegaly (growth hormone excess) can elevate testosterone levels through increased sex hormone production 1

• Cushing's disease may paradoxically increase androgen production in some cases despite the typical association with hypogonadism 1

Medications and Substances

• Growth hormone administration can increase testosterone levels through stimulation of testicular function 1

• Glucocorticoid therapy may alter testosterone metabolism and binding proteins, though typically associated with decreased levels 1

• Anabolic androgenic steroids (even if patient denies use) should be suspected, as these are widely available and may be used without disclosure 1

Metabolic and Physiological Factors

• Insulin resistance and metabolic syndrome typically lower testosterone, so elevated levels in this context are unusual and suggest exogenous supplementation 1, 2

• Obesity is associated with decreased testosterone due to increased aromatization to estrogen and lower SHBG, making elevated testosterone in obese older men particularly suspicious 1, 2

• Hypothyroidism can paradoxically increase SHBG and alter testosterone metabolism, though total testosterone is typically low 1

Important Clinical Considerations

Age-Related Context

• Normal aging is associated with declining testosterone, not elevation—total testosterone decreases approximately 1-2% per year after age 30, and bioavailable testosterone falls even more dramatically 2, 3

• Older men with truly elevated testosterone (>700-800 ng/dL) without supplementation are rare and require thorough investigation 4, 2

Diagnostic Pitfalls to Avoid

• Verify the laboratory result with repeat morning (8-10 AM) total testosterone measurement using an accurate assay, as assay variability and timing can produce spurious elevations 4

• Measure LH and FSH levels to distinguish between primary (testicular) overproduction (suppressed LH/FSH) versus secondary causes (elevated or normal LH/FSH) 4

• Screen for surreptitious anabolic steroid use by measuring LH/FSH—suppressed gonadotropins with elevated testosterone strongly suggest exogenous androgen administration 1, 4

• Consider DHEA-S measurement to evaluate for adrenal androgen excess if testicular pathology is excluded 1

• Obtain testicular ultrasound if LH/FSH are suppressed with elevated testosterone to rule out Leydig cell tumor 1

Red Flags Requiring Urgent Evaluation

• Rapidly rising testosterone levels suggest tumor or exogenous administration 1

• Virilization symptoms (acne, increased body hair, aggressive behavior) in the context of elevated testosterone warrant immediate investigation 1

• Suppressed LH/FSH with elevated testosterone is pathognomonic for either exogenous testosterone/anabolic steroids or autonomous testosterone production from tumor 1, 4

Clinical Algorithm

1. Confirm elevation with repeat morning testosterone measurement 4
2. Measure LH, FSH, and DHEA-S to localize the source 1, 4
3. If LH/FSH suppressed: Consider exogenous androgens (most common) or testicular tumor—obtain testicular ultrasound 1, 4
4. If DHEA-S elevated: Evaluate for adrenal pathology with adrenal imaging 1
5. If no clear cause identified: Consider growth hormone excess, Cushing's disease, or occult medication/supplement use 1

Most Common Scenario in Clinical Practice

In the vast majority of cases where older men present with unexpectedly elevated testosterone, the cause is undisclosed use of testosterone preparations, anabolic steroids, or supplements containing androgens 1. Direct but non-judgmental questioning about all supplements, "anti-aging" treatments, and performance-enhancing substances is essential 1.