16A. Fatigue: Common Physiologic Contributing Factors—An Algorithm for Evaluation & Management

Fatigue is a common problem, with high prevalence in the community, and is a common complaint for individuals seeking primary, specialty, and integrative consultation. It often defies efforts to find a specific treatable etiology and may lead to chronic impairment. Background will include discussion of chronic fatigue syndrome and depression, as differentiated from fatigue as a symptom. Also, dimensions of fatigue will be noted. A simple protocol will be presented with 5 lab tests to identify physiologic factors contributing to fatigue. These include thyroid function, vitamin D, ferritin, DHEA-Sulfate, and methyltetrahydrafolate reductase (MTHFR) gene mutation. The scientific rationale for screening each of these will be presented, as well as the suggestion that we revise lab norms from what is present in the normal population to values that reflect optimal physiological functioning. As an example of this, the upper limit of TSH is commonly cited as 4.5 or 5, but there is discussion in both the endocrine and integrative medicine fields that levels over 3 may reflect dysfunction. The normal range for Vitamin D3 was changed from population norms to minimal values needed for optimal health. Similarly, low normal ferritin or DHEA may contribute to fatigue, and these may represent opportunities to impact on cellular metabolism in a way that enhances energy and physiologic functioning. MTHFR is an enzymatic pathway key in folate metabolism, and 2 common polymorphisms result in deficiency of this enzyme with potential health consequences and fatigue. The presentation will conclude with lab and clinical assessments of a case series. Exemplar case studies will be discussed with tracking of response to supplementation, using standardized measures of mood and fatigue. Cases will also include discussion of dietary management, supplements, medications, exercise, and mind-body approaches.