Health-related quality of life in T1DM patients after high-dose cholecalciferol supplementation: data from a pilot clinical trial.

BACKGROUND: Type 1 Diabetes Mellitus (T1DM) impacts health-related quality of life (HRQoL). Cross-sectional studies suggest that low levels of vitamin D (VD) may impair HRQoL, however, the effect of VD supplementation on quality of life in T1DM patients has not yet been clarified. Our study evaluated the effects of high-dose VD supplementation on HRQoL in T1DM. METHODS: We performed a prospective study with 64 patients receiving cholecalciferol (4000 IU/day for patients with 25-OH-vitamin D [25(OH)D] between 30 and 60 ng/mL, and 10,000 IU/day for those with 25(OH)D below 30 ng/mL) for 12 weeks, as part of a research protocol. HRQoL was assessed with EuroQol instruments (EQ-5D and EQ-VAS). RESULTS: There was an improvement in global EQ-5D index, and analysing specifically the EQ-5D domains, we observed an improvement in mobility (1.3 ± 0.6 versus 1.1 ± 0.3, p < 0.01). Evaluating possible outcome influencing variables, we detected a reduction in albuminuria at the end of the trial, without changes in BMI, lipids, blood pressure, glycemic control and insulin doses. We found correlations between final albuminuria and the dimensions: mobility (r = 0.6; p < 0.01), personal care (r = 0.7; p < 0.01), pain and discomfort (r = 0.6; p < 0.01) and habitual activities (r = 0.6; p < 0.01), suggesting an association between albuminuria reduction and the impact of VD supplementation on HRQoL. CONCLUSION: Our data showed that high doses of cholecalciferol supplementation can improve HRQoL in patients with T1DM, and the reduction of albuminuria seems to be an important factor in this context. TRIAL REGISTRATION: (ISRCTN32601947), 03/06/2017 retrospectively registered.

Association Between 25(OH)Vitamin D, HbA1c and Albuminuria in Diabetes Mellitus: Data From a Population-Based Study (VIDAMAZON).

Background: The effect of glycemic control on diabetic kidney disease (DKD) is well known. Recent evidence has suggested that Vitamin D (VD) may have a nephroprotective effect in diabetes, but the relationship between VD, glycemic control, and albuminuria has yet to be clarified. Objective: Evaluate the relationship between 25-hydroxy-vitamin D [25(OH)D], HbA1c, and albuminuria in Diabetes Mellitus (DM). Patients and Methods: Cross-sectional study with 1576 individuals with DM who had 25(OH)D, HbA1c, and albuminuria levels measured. Patients with abnormal creatinine levels were excluded, in order to avoid interference on VD levels by impaired kidney function. Results: Patients with HbA1c ≥7% had lower 25(OH)D when compared to patients with HbA1c <7% (29.7 ± 10.2 vs 28.1 ± 9.9 ng/ml, p = 0.003) and 25(OH)D levels seems to predict 1.5% of HbA1c behavior. The 25(OH)D concentrations in patients with normoalbuminuria were higher than the levels observed in those with micro or macroalbuminuria (29.8 ± 9.0 vs 26.8 ± 8.6 and 25.1 ± 7.6, respectively, p = 0.001), patients who had 25(OH)D <20 ng/ml and 25(OH)D <30 ng/ml were at a higher risk of presenting albuminuria [OR = 2.8 (95% CI = 1.6 - 4.9), p<0.001, and OR = 2.1 (95% CI = 1.3 - 4.6), p<0.001, respectively]. In our regression model, albuminuria was influenced by HbA1c (r² = 0.076, p<0.00001) and 25(OH)D (r² = 0.018, p = 0.002) independently. Conclusion: Our study found an association between vitamin D levels, HbA1c and DKD. Additionally, our data suggest that the association between urinary albumin excretion and vitamin D levels is independent of glycemic control in patients with diabetes. Even though our patients presented normal creatinine levels, it is necessary further prospective studies to confirm if this association precedes or not the loss of renal function.

High-dose Cholecalciferol Supplementation Reducing Morning Blood Pressure in Normotensive DM1 Patients.

BACKGROUND: Vitamin D (VD) deficiency has been related to several endocrine metabolic and cardiovascular diseases. The effect of VD supplementation on blood pressure (BP) in patients with diabetes is controversial. OBJECTIVE: The aim of this study was to evaluate high-dose vitamin D supplementation effects on blood pressure of normotensive patients with diabetes mellitus 1 (DM1) patients by 24-hour ambulatory blood pressure monitoring (ABPM). METHODS: We performed a clinical trial including 35 DM1 normotensive patients, who received doses of 4,000 or 10,000 IU/day of cholecalciferol for 12 weeks according to previous VD levels. They underwent 24-hour ABPM, along with glycated hemoglobin, creatine, lipids profile and PCRus dosage before and after VD supplementation. RESULTS: We found an expressive reduction of systolic and diastolic morning blood pressures (117±14 vs 112±14, p<0,05; 74±9 vs 70±10 mmHg, p<0,05, respectively) with no changes in other pressoric markers. Besides, we noticed a relationship between levels of VD after supplementation and diastolic morning blood pressure (r= -0,4; p<0.05). CONCLUSION: Our study suggests an association between supplementation of high doses of vitamin D and the reduction of morning blood pressure in normotensive DM1 patients.

Improvement in Cardiovascular Autonomic Neuropathy After High-Dose Vitamin D Supplementation in Patients With Type 1 Diabetes.

Background: Cardiovascular autonomic neuropathy (CAN) is associated with diabetes mellitus, increasing morbidity and mortality. Some cross-sectional studies associated CAN with low 25-hydroxyvitamin D levels. The aim of our study was to evaluate the effect of high-dose vitamin D (VD) supplementation on CAN in Type 1 Diabetes Mellitus (T1DM) patients. Methods: We performed a prospective study with 23 patients diagnosed with T1DM and CAN. Subjects with VD levels <30 ng/ml received 10,000 IU/day; the ones with VD levels between 30-60 ng/ml were given 4,000 IU/day for 12 weeks. Results: There was an improvement in CAN parameters related to resting heart rate variability, such as time domain parameters [Maximum RR interval (0.77 ± 0.11 vs 0.94 ± 0.51 s, p <0.05), Mean length of regular RR intervals (0.71 ± 0.10 vs 0.76 ± 0.09 s, p <0.05) and Standard deviation of all NN intervals (0.02 ± 0.01 vs 0.03 ± 0.02 s; p <0.01)] and frequency domain parameters [Low Frequency (1.9 ± 0.5 vs 2.5 ± 0.9 s, p < 0.001), Total Power (2.5 ± 0.4 vs 2.8 ± 0.6 s, p <0.05)]. In addition, there was a correlation between absolute VD level variation and posttreatment High Frequency (%), as well as among percent variation in VD level and end-of-study Low Frequency/High Frequency ratio (r=0.6, p<0.01; r= -0.5, p<0.05, respectively). Conclusion: Our pilot study is the first to suggest a strong association between high-dose vitamin D supplementation and improved cardiovascular autonomic neuropathy in T1DM patients. It occurred without any variation in HbA1C, blood pressure levels, lipids, and insulin dose. Clinical Trial Registration: http://www.isrctn.com/ISRCTN32601947, identifier ISRCTN32601947.