Trauma and amyotrophic lateral sclerosis: a systematic review and meta-analysis

Abstract

Background: Trauma especially head trauma is considered a potential risk factor of amyotrophic lateral sclerosis (ALS), but their association has not been well established. We aimed to determine the association of prior trauma with ALS risk. Methods: This study was performed according to the Meta-Analysis of Observational Studies in Epidemiology guideline to assess related literatures, and a random-effects model was used to calculate odds ratios (ORs) and 95% confidence intervals (CIs). Results: Twenty-nine eligible articles involving 18,390 cases and 6,519,391 controls were included in this meta-analysis. The results showed that trauma was associated with an increased risk of ALS (pooled OR = 1.51, 95% CI: 1.32–1.73). Besides, patients with trunk trauma, head trauma and lower limb trauma had an increased risk of ALS, whereas no evidence suggested that upper limb trauma and spine trauma could increase ALS risk. Considering the number of traumatic events, the association between trauma and ALS risk was significant for patients with repeated trauma events (pooled OR = 1.21, 95% CI: 1.07–1.38). The results showed that individuals with a history of trauma within 5 years were more likely to be diagnosed with ALS (pooled OR = 1.84, 95% CI: 1.56–2.17). Importantly, both old trauma and very old trauma were found to be associated with an increased risk of ALS (pooled OR = 1.24, 95% CI: 1.12–1.38; pooled OR = 1.28, 95% CI: 1.10–1.49; respectively). Conclusions: This meta-analysis indicated that trauma could increase ALS risk, which may be applied for the clinicians to tailor targeted treatment regimens and make prophylactic strategies for ALS in traumatic patients.

Keywords:

• Amyotrophic lateral sclerosis
• trauma
• risk factor
• meta-analysis

Author contributions

All authors contributed to the study conception and design. Literature search, data collection and analysis were performed by Guodong Liu, Dongqing Gu, Shan Ou, Mingshuang Tang, Zhiyong Yin and Zhengguo Wang. The first draft of the manuscript was written by Dongqing Gu, revised by Guodong Liu, and all authors commented on previous versions of the manuscript. All authors read and approved the final manuscript.

Declaration of interest

The authors report no conflicts of interest. The authors alone are responsible for the content and writing of this article.

Data availability statement

The datasets analyzed and generated during the current study are available from the corresponding author on reasonable request.

Additional information

Funding

This work was supported by the China Postdoctoral Science Foundations [2014M562594, 2015T81090] and Postdoctoral Science Foundation of Chongqing [Xm2015034].