Vitamin D in palliative care : aspects on pain, infections and quality of life

The World Health Organization’s (WHO’s) definition of palliative care stresses the importance of early identification and assessment of physical symptoms in the palliative patient, to prevent and relieve suffering. The overall goal is to improve quality of life, and it is thus important that side effects of medical treatment do not outweigh beneficial effects. Vitamin D has few and mild side effects, and vitamin D treatment has well defined uses in medicine. However, the role of vitamin D supplementation to patients with advanced or metastatic cancer has rarely been studied. The papers included in this thesis aim at understanding the possible effects and optimal use of vitamin D in symptom management in palliative cancer patients, and to study effects of antibiotics in end-of-life cancer patients. In study I, we investigated the effect of antibiotic use in patients in the last week of life. Almost 50 % in the studied cohort were treated with antibiotics during the last week in life; 37% of all patients and 50% of patients with septic symptoms experienced symptom relief. Based on a study showing association between lower vitamin D levels and higher doses of opioids in patients with advanced cancer, we performed a pilot study to investigate effects of vitamin D in pain management, Quality of Life (QoL) and infections in patients with advanced or metastatic cancer, study II. Participants (n=39, with 25-hydroxyvitamin D < 75 nmol/L) received vitamin D 4000 IU/day for twelve weeks and were matched to untreated controls. After one month, the mean change in opioid dose was significantly lower in the vitamin D supplemented group -46 μg/h (95% CI -24-78), and difference increased over time. Differences in antibiotic use and QoL were also significant, in favor of the supplementation group. The encouraging results from study II were used to plan study III, a multicentre, randomized, double blind placebo-controlled trial investigating the effect of vitamin D supplementation (4000 IU/day) on pain, infections, fatigue and QoL for 12 weeks. Last patient out was in June 2020, and results (submitted but not yet accepted manuscript) indicate a significant effect on opioid use and fatigue, but not on infections and QoL. In a post-hoc analysis of a previously studied cohort of immunodeficient patients, study IV, we compared the effectiveness of vitamin D supplementation administered as oil drops versus powdered tablets in raising the individual’s vitamin D level. There was no