Low DHEAS in a 39-Year-Old Male: Clinical Significance
A low DHEAS level in a 39-year-old male is a useful initial sign of primary adrenal insufficiency (PAI) that should not be overlooked, though it cannot be used in isolation to make the diagnosis. 1
Primary Diagnostic Consideration: Adrenal Insufficiency
Low DHEAS levels that fall well below the lower limit of normal for age and sex serve as an important marker for PAI. The Endocrine Society's 2016 guideline explicitly states that DHEAS levels are a useful initial sign of PAI, though they emphasize this finding must be confirmed with additional testing 1.
When you encounter low DHEAS in this patient, you should:
Measure morning cortisol and ACTH levels immediately. If morning cortisol is <140 nmol/L (5 μg/dL) combined with ACTH elevated more than 2-fold above the upper limit of normal, PAI is highly likely 1
Perform a corticotropin stimulation test (250 μg ACTH, measuring cortisol at baseline and 30-60 minutes) to confirm the diagnosis, as this is the diagnostic gold standard for PAI 1
Recent evidence (2025) confirms diagnostic utility: DHEAS demonstrates 82% sensitivity and 82% specificity for diagnosing mild autonomous cortisol secretion when using cutoffs between 60-70 mcg/dL 2, and provides additional diagnostic value for adrenal insufficiency 2
Why DHEAS Matters in This Context
DHEAS is uniformly low in patients with corticotropin deficiency 3. A 2003 study demonstrated that a normal age- and gender-specific serum DHEAS level makes the diagnosis of corticotropin deficiency extremely unlikely 3. The receiver operating characteristic curve for baseline DHEAS had an area of 0.984, indicating excellent diagnostic accuracy 3.
Important Caveats
Do not diagnose PAI based on DHEAS alone because:
- DHEAS levels may be low in some individuals, especially in older age groups, without PAI 1
- DHEAS naturally declines with age (physiologically peaks between ages 20-30 years) 1
- At 39 years old, this patient is past peak DHEAS levels but still relatively young for age-related decline alone
Alternative Considerations (Less Likely at Age 39)
While the guidelines focus on adrenal insufficiency, other conditions associated with low DHEAS include:
- Adrenocortical tumors: Low DHEAS can be a marker of adrenocortical adenomas 4, though this typically presents with other hormonal abnormalities
- Autonomous cortisol secretion: DHEAS <40 mcg/dL combined with ACTH <10 pg/mL has 92% specificity for this diagnosis 5
Clinical Action Algorithm
- Obtain confirmatory testing: Morning cortisol, ACTH, and corticotropin stimulation test
- If PAI is confirmed, initiate glucocorticoid replacement (hydrocortisone 15-25 mg in divided doses) and mineralocorticoid replacement (fludrocortisone 50-100 μg) 1
- Monitor for symptoms: Fatigue, postural hypotension, salt craving, weight loss
- Do not delay treatment if the patient has severe symptoms or is in adrenal crisis—give IV hydrocortisone immediately before diagnostic test results are available 1
The key message: Low DHEAS in a 39-year-old male is a red flag for adrenal insufficiency requiring immediate further evaluation with cortisol and ACTH testing, followed by corticotropin stimulation testing for definitive diagnosis.