Serum magnesium levels and lung cancer risk: a meta-analysis.

BACKGROUND: Whether serum magnesium levels were lower in patients with lung cancer than that in healthy controls is controversial. The aim of this study was to identify and synthesize all citations evaluating the relationship between serum magnesium levels and lung cancer. METHODS: We searched PubMed, WanFang, China National Knowledge Internet (CNKI), and SinoMed databases for relevant studies before December 31, 2017. Two authors independently selected studies, extracted data, and assessed risk of bias. RESULTS: Eleven citations comprising 707 cases with lung cancer and 7595 healthy controls were included in our study. Serum magnesium levels were not significantly lower in patients with lung cancer [summary SMD = 0.193, 95%CI = - 1.504 to 1.890] when compared to health controls, with significant heterogeneity (I2 = 99.6%, P < 0.001) found. Negative associations were found among Asian populations [summary SMD = 0.229, 95%CI = - 1.637 to 2.094] and European populations [summary SMD = - 0.168, 95%CI = - 0.482 to 0.147]. No publication bias was found using the test of Egger and funnel plot. CONCLUSIONS: Our study suggested that serum magnesium levels had no significant association on lung cancer risk.