Supplementation of Vitamin D Deficiency in Patients with Neuroendocrine Tumors Using Over-the-Counter Vitamin D3 Preparations.

Vitamin D (vit-D) deficiency is highly prevalent in patients with gastro-entero-pancreatic neuroendocrine tumors (GEP-NET) and has been linked to reduced overall survival. We here assessed the vit-D status in 183 patients with GEP-NET at the time of their first presentation in the ARDEN NET Centre. We further examined the effect of simple advice to increase vit-D intake using over-the-counter vit-D preparations [colecalciferol (Vit-D3), 1,000-2,000 units/day], over a prospective observation period of 24 mo. At baseline, only 33.3% of patients showed vit-D sufficiency (25-OH-vit-D; >50 nmol/L), the remainder was insufficient (31.3%; 25-OH-vit-D; 25-50 nmol/L) or deficient (35.5%; 25-OH-vit-D; <25 nmol/L). Repeated advice to increase vit-D intake at routine 6-monthly follow-up appointments was associated with increased 25-OH-vit-D from 37.8 ± 3.5 nmol/L at baseline to 60.4 ± 5.6 nmol/L (P < 0.0001) and 56.8 ± 7.0 nmol/L (P = 0.039) after 12 and 24 mo. Percentage of vit-D insufficiency decreased from 66.6% at baseline to 44.9% and 46.2% after 12 and 24 months, respectively. Previous abdominal surgery, but not treatment with somatostatin analogues predicted 25-OH-vit-D levels in bootstrapped linear regression analyses (P = 0.037). In summary, simple advice to increase vit-D intake using over-the-counter preparations was associated with significant improvement of vit-D deficiency/insufficiency, although, 15% of GEP-NET patients remained deficient and may benefit from additional measures of vit-D replacement.

Feasibility and effects of intra-dialytic low-frequency electrical muscle stimulation and cycle training: A pilot randomized controlled trial.

BACKGROUND AND OBJECTIVES: Exercise capacity is reduced in chronic kidney failure (CKF). Intra-dialytic cycling is beneficial, but comorbidity and fatigue can prevent this type of training. Low-frequency electrical muscle stimulation (LF-EMS) of the quadriceps and hamstrings elicits a cardiovascular training stimulus and may be a suitable alternative. The main objectives of this trial were to assess the feasibility and efficacy of intra-dialytic LF-EMS vs. cycling. DESIGN, SETTING, PARTICIPANTS, AND MEASUREMENTS: Assessor blind, parallel group, randomized controlled pilot study with sixty-four stable patients on maintenance hemodialysis. Participants were randomized to 10 weeks of 1) intra-dialytic cycling, 2) intra-dialytic LF-EMS, or 3) non-exercise control. Exercise was performed for up to one hour three times per week. Cycling workload was set at 40-60% oxygen uptake (VO2) reserve, and LF-EMS at maximum tolerable intensity. The control group did not complete any intra-dialytic exercise. Feasibility of intra-dialytic LF-EMS and cycling was the primary outcome, assessed by monitoring recruitment, retention and tolerability. At baseline and 10 weeks, secondary outcomes including cardio-respiratory reserve, muscle strength, and cardio-arterial structure and function were assessed. RESULTS: Fifty-one (of 64 randomized) participants completed the study (LF-EMS = 17 [77%], cycling = 16 [80%], control = 18 [82%]). Intra-dialytic LF-EMS and cycling were feasible and well tolerated (9% and 5% intolerance respectively, P = 0.9). At 10-weeks, cardio-respiratory reserve (VO2 peak) (Difference vs. control: LF-EMS +2.0 [95% CI, 0.3 to 3.7] ml.kg-1.min-1, P = 0.02, and cycling +3.0 [95% CI, 1.2 to 4.7] ml.kg-1.min-1, P = 0.001) and leg strength (Difference vs. control: LF-EMS, +94 [95% CI, 35.6 to 152.3] N, P = 0.002 and cycling, +65.1 [95% CI, 6.4 to 123.8] N, P = 0.002) were improved. Arterial structure and function were unaffected. CONCLUSIONS: Ten weeks of intra-dialytic LF-EMS or cycling improved cardio-respiratory reserve and muscular strength. For patients who are unable or unwilling to cycle during dialysis, LF-EMS is a feasible alternative.