Association of Vitamin D Supplementation with Cardiovascular Events: A Systematic Review and Meta-Analysis.

BACKGROUND: low vitamin D status has been associated with an increased incidence of cardiovascular events. However, whether vitamin D supplementation would reduce the incidence of cardiovascular events remains unclear. PURPOSE: To perform a systematic review and meta-analysis of the effect of vitamin D supplementation on the mortality and incidence of cardiovascular events. DATA SOURCES: We searched Medline, Embase, and the Cochrane Central Register of Controlled Trials from their inception until 3 May 2022. STUDY SELECTION: Two authors searched for randomized clinical trials that reported vitamin D supplementation's effect on cardiovascular events outcomes. DATA EXTRACTION: Two authors conducted independent data extraction. DATA SYNTHESIS: We identified 41,809 reports; after exclusions, 18 trials with a total of 70,278 participants were eligible for analysis. Vitamin D supplementation was not associated with the mortality of cardiovascular events (RR 0.96, 95% CI 0.88-1.06, I2 = 0%), the incidence of stroke (RR 1.05, 95% CI 0.92-1.20, I2 = 0%), myocardial infarction (RR 0.97, 95% CI 0.87-1.09, I2 = 0%), total cardiovascular events (RR 0.97, 95% CI 0.91-1.04, I2 = 27%), or cerebrovascular events (RR 1.01, 95% CI 0.87-1.18, I2 = 0%). LIMITATION: Cardiovascular events were the secondary outcome in most trials and thus, might be selectively reported. CONCLUSION: In this meta-analysis of randomized clinical trials, vitamin D supplementation was not associated with a lower risk of cardiovascular events than no supplementation. These findings do not support the routine use of vitamin D supplementation in general.

Lactate dehydrogenase as promising marker for prognosis of brain metastasis.

BACKGROUND: Lactate dehydrogenase (LDH) is a biomarker for cancer. However, the relationship between serum LDH levels and the survival of patients with brain metastasis has been fully revealed. We aimed to evaluate the serum LDH levels and assess its prognostic value in patients with BM. METHODS: The serum LDH levels were collected from 2507 patients with BM. Patients were categorized into four groups according to the quartile of serum LDH levels. The association between serum LDH levels and overall survival (OS) was evaluated using Cox regression models and Kaplan-Meier curves. Three predictive models were used to evaluate patients. RESULTS: The Kaplan-Meier curve for survival by the serum LDH group demonstrates clear separation between four groups (P < 0.001). The participants in the lower group had longer OS than those in the higher group. After adjusting in multivariate Cox regression models remained significant for patients in the Q4 compared with patients in the Q1 (Q4:Q1 OR 1.58, 95% CI 1.38-1.80). Furthermore, the GPA-LDH model generates a pooled area under the curve of 0.630 (95% CI 0.600, 0.660). CONCLUSIONS: Serum LDH levels and OS in patients with brain metastasis is an inverse association. Moreover, Serum LDH levels can improve the prognosis of the GPA model.