1.
Comparison of Paricalcitol and Calcitriol in Dialysis Patients With Secondary Hyperparathyroidism: A Meta-Analysis of Randomized Controlled Studies.
Zhang, T, Ju, H, Chen, H, Wen, W
Therapeutic apheresis and dialysis : official peer-reviewed journal of the International Society for Apheresis, the Japanese Society for Apheresis, the Japanese Society for Dialysis Therapy. 2019;(1):73-79
Abstract
Paricalcitol and calcitriol are widely used for the treatment of secondary hyperparathyroidism in dialysis patients. We conducted a systematic review and meta-analysis to compare the efficacy and safety of paricalcitol and calcitriol for secondary hyperparathyroidism in dialysis patients. PubMed, EMbase, Web of Science, EBSCO, and Cochrane library databases were systematically searched. Randomized controlled trials (RCT) assessing the efficacy of paricalcitol and calcitriol for secondary hyperparathyroidism in dialysis patients are included. Two investigators independently searched articles, extracted data, and assessed the quality of included studies. Meta-analysis was carried out using the random-effect model. Six randomized controlled trials are included in the meta-analysis. Overall, compared with calcitriol treatment for secondary hyperparathyroidism in dialysis patients, paricalcitol treatment has comparable ≥50% reduction of parathyroid hormone (risk ratio [RR] = 1.33; 95% CI = 0.93-1.91; P = 0.12), calcium concentration (standard mean difference [Std. MD] = -0.21; 95% CI = -0.94 to 0.52; P = 0.58), phosphate concentration (Std. MD = -0.17; 95% CI = -0.58 to 0.24; P = 0.42), calcium phosphate (Std. MD = -0.08; 95% CI = -0.49-0.34; P = 0.71), alkaline phosphatase (Std. MD = -0.21; 95% CI = -0.73-0.31; P = 0.43), hypercalcemia (RR = 1.43; 95% CI = 0.51 to 3.98; P = 0.49), adverse events (RR = 0.79; 95% CI = 0.42-1.49; P = 0.47), and serious adverse events (RR = 0.78; 95% CI = 0.47-1.30; P = 0.33). Paricalcitol and calcitriol result in similar ≥50% reduction of parathyroid hormone, calcium concentration, phosphate concentration, calcium phosphate, alkaline phosphatase, hypercalcemia, adverse events, and serious adverse events for secondary hyperparathyroidism in dialysis patients.
2.
Vitamin D and Calcium for the Prevention of Fracture: A Systematic Review and Meta-analysis.
Yao, P, Bennett, D, Mafham, M, Lin, X, Chen, Z, Armitage, J, Clarke, R
JAMA network open. 2019;(12):e1917789
Abstract
IMPORTANCE Vitamin D and calcium supplements are recommended for the prevention of fracture, but previous randomized clinical trials (RCTs) have reported conflicting results, with uncertainty about optimal doses and regimens for supplementation and their overall effectiveness. OBJECTIVE To assess the risks of fracture associated with differences in concentrations of 25-hydroxyvitamin D (25[OH]D) in observational studies and the risks of fracture associated with supplementation with vitamin D alone or in combination with calcium in RCTs. DATA SOURCES PubMed, EMBASE, Cochrane Library, and other RCT databases were searched from database inception until December 31, 2018. Searches were performed between July 2018 and December 2018. STUDY SELECTION Observational studies involving at least 200 fracture cases and RCTs enrolling at least 500 participants and reporting at least 10 incident fractures were included. Randomized clinical trials compared vitamin D or vitamin D and calcium with control. DATA EXTRACTION AND SYNTHESIS Two researchers independently extracted data according to the Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) guidelines and assessed possible bias. Rate ratios (RRs) were estimated using fixed-effects meta-analysis. Data extraction and synthesis took place between July 2018 and June 2019. MAIN OUTCOMES AND MEASURES Any fracture and hip fracture. RESULTS In a meta-analysis of 11 observational studies (39 141 participants, 6278 fractures, 2367 hip fractures), each increase of 10.0 ng/mL (ie, 25 nmol/L) in 25 (OH)D concentration was associated with an adjusted RR for any fracture of 0.93 (95% CI, 0.89-0.96) and an adjusted RR for hip fracture of 0.80 (95% CI, 0.75-0.86). A meta-analysis of 11 RCTs (34 243 participants, 2843 fractures, 740 hip fractures) of vitamin D supplementation alone (daily or intermittent dose of 400-30 000 IU, yielding a median difference in 25[OH]D concentration of 8.4 ng/mL) did not find a reduced risk of any fracture (RR, 1.06; 95% CI, 0.98-1.14) or hip fracture (RR, 1.14; 95% CI, 0.98-1.32), but these trials were constrained by infrequent intermittent dosing, low daily doses of vitamin D, or an inadequate number of participants. In contrast, a meta-analysis of 6 RCTs (49 282 participants, 5449 fractures, 730 hip fractures) of combined supplementation with vitamin D (daily doses of 400-800 IU, yielding a median difference in 25[OH]D concentration of 9.2 ng/mL) and calcium (daily doses of 1000-1200 mg) found a 6% reduced risk of any fracture (RR, 0.94; 95% CI, 0.89-0.99) and a 16% reduced risk of hip fracture (RR, 0.84; 95% CI, 0.72-0.97). CONCLUSIONS AND RELEVANCE In this systematic review and meta-analysis, neither intermittent nor daily dosing with standard doses of vitamin D alone was associated with reduced risk of fracture, but daily supplementation with both vitamin D and calcium was a more promising strategy.
3.
Vitamin D exposure and Risk of Breast Cancer: a meta-analysis.
Estébanez, N, Gómez-Acebo, I, Palazuelos, C, Llorca, J, Dierssen-Sotos, T
Scientific reports. 2018;(1):9039
Abstract
UNLABELLED The relationship between vitamin D and breast cancer is still controversial. The present meta-analysis examines the effects of the 25(OH)D, 1,25(OH)2D and vitamin D intake on breast cancer risk. For this purpose, a PubMed, Scopus and Web of Science-databases search was conducted including all papers published with the keywords "breast cancer" and "vitamin D" with at least one reported relative risk (RR) or odds ratio (OR). In total sixty eight studies published between 1998 and 2018 were analyzed. Information about type of study, hormonal receptors and menopausal status was retrieved. Pooled OR or RR were estimated by weighting individual OR/RR by the inverse of their variance Our study showed a protective effect between 25 (OH) D and breast cancer in both cohort studies (RR = 0.85, 95%CI:0.74-0.98) and case-control studies (OR = 0.65, 95%CI: 0.56-0.76). However, analyzing by menopausal status, the protective vitamin D - breast cancer association persisted only in the premenopausal group (OR = 0.67, 95%CI: 0.49-0.92) when restricting the analysis to nested case-control studies. No significant association was found for vitamin D intake or 1,25(OH)2D. CONCLUSION This systematic review suggests a protective relationship between circulating vitamin D (measured as 25(OH) D) and breast cancer development in premenopausal women.