RESUMEN
BACKGROUND: Vitamin D deficiency in noncancer patients is associated with symptoms of fatigue, muscle weakness, and depression. These symptoms are common among advanced cancer patients. We investigated the prevalence of low serum vitamin D levels in cancer patients with fatigue or poor appetite and their association with symptom burden and other correctable endocrine abnormalities. METHODS: This was a retrospective review of 100 consecutive cancer patients with appetite or fatigue scores of ≥4 of 10 referred to a supportive care clinic. We investigated serum levels of 25(OH) vitamin D, cortisol, thyroid-stimulating hormone, and bioavailable testosterone. Symptoms were measured by the Edmonton Symptom Assessment Scale. Serum 25(OH) vitamin D <20 ng/mL was considered deficient; ≥20 ng/mL and <30 ng/mL were considered insufficient. RESULTS: Patients were predominantly male (68%) and white (66%), with a median age of 60 years (range, 27-91 years). Gastrointestinal (30%) and lung (22%) cancers were predominant. Forty-seven patients (47%) were vitamin D deficient and 70 (70%) were insufficient. Thirteen of 70 patients (19%) with vitamin D insufficiency were on supplementation. Vitamin D deficiency was more common among nonwhites (82% versus 36%) and females. No significant association was found between vitamin D and symptoms. Hypogonadic males had a significantly lower mean 25(OH) vitamin D level than eugonadic males. CONCLUSIONS: Low vitamin D levels were highly prevalent among advanced cancer patients with cachexia or fatigue. Vitamin D deficiency was more frequent among nonwhite and female patients. Vitamin D levels were also significantly lower in male patients with hypogonadism.