Iron insufficiency and hypovitaminosis D in adolescents with chronic fatigue and orthostatic intolerance

South Med J. 2011 Aug;104(8):609-11. doi: 10.1097/SMJ.0b013e3182246809.


Objectives: More than 10% of adolescents suffer from severe fatigue and/or orthostatic intolerance. Adult studies show correlations between iron insufficiency and fatigue as well as between hypovitaminosis D and non-specific pain. We sought to determine whether there were correlations between nutritional factors (iron status, and serum vitamin D levels) and chronic ill health.

Methods: We reviewed records of 188 adolescents with symptoms of fatigue and/or orthostatic intolerance and who underwent autonomic reflex screening.

Results: Of the 188 patients, 130 patients (69%) had excessive postural tachycardia (PT) with a heart rate (HR) change of ≥30 bpm. 62 patients (47%, n = 131) had iron insufficiency with low iron stores, and 29 patients (22%, n = 131) were iron deficient. HR change did not correlate to ferritin level (P = 0.15). 21 patients (22%, n = 95) had hypovitaminosis D (25-hydroxyvitamin D ≤20 ng/mL). There was a significant association with hypovitaminosis D and orthostatic intolerance (P = 0.024).

Conclusion: In patients presenting with chronic fatigue and/or orthostatic intolerance, low ferritin levels and hypovitaminosis D are common, especially in patients with PT.

MeSH terms

  • Adolescent
  • Blood Pressure
  • Fatigue Syndrome, Chronic / blood*
  • Fatigue Syndrome, Chronic / complications
  • Fatigue Syndrome, Chronic / physiopathology
  • Female
  • Ferritins / blood
  • Heart Rate
  • Humans
  • Hypotension, Orthostatic / complications
  • Iron / blood*
  • Iron Deficiencies
  • Male
  • Postural Orthostatic Tachycardia Syndrome / blood*
  • Postural Orthostatic Tachycardia Syndrome / complications
  • Postural Orthostatic Tachycardia Syndrome / physiopathology
  • Posture / physiology
  • Retrospective Studies
  • Vitamin D Deficiency / blood*


  • Ferritins
  • Iron