TY - JOUR T1 - Risk factors for cognitive impairment in amyotrophic lateral sclerosis: a systematic review and meta-analysis JF - Journal of Neurology, Neurosurgery & Psychiatry JO - J Neurol Neurosurg Psychiatry SP - 688 LP - 693 DO - 10.1136/jnnp-2020-325701 VL - 92 IS - 7 AU - Tianmi Yang AU - Yanbing Hou AU - Chunyu Li AU - Bei Cao AU - Yangfan Cheng AU - Qianqian Wei AU - Lingyu Zhang AU - Huifang Shang Y1 - 2021/07/01 UR - http://jnnp.bmj.com/content/92/7/688.abstract N2 - Objective Cognitive impairment is a common, far-reaching but imperceptible manifestation in patients with amyotrophic lateral sclerosis (ALS). We aimed to identify the risk factors for cognitive impairment in ALS.Methods We searched PubMed and EMBASE for cross-sectional, case–control and cohort studies that reported predictors of cognitive impairment in ALS. The obtained data were meta-analysed to generate overall ORs and 95% CIs.Results Twenty-seven eligible articles reporting on 6799 individuals were included out of 20 501 records. Nine predictors were identified: C9orf72 (OR 3.62, 95% CI 1.76 to 7.45), dysarthria (OR 2.25, 95% CI 1.20 to 4.22), family history of ALS (OR 1.76, 95% CI 1.18 to 2.61), predominant upper motor neuron (PUMN) phenotype (OR 1.73, 95% CI 1.09 to 2.73) and bulbar onset (OR 1.54, 95% CI 1.28 to 1.87) increased risk factors for cognitive impairment in ALS. ALS Functional Rating Scale-Revised scores, sex, age or education level were not significantly associated with cognitive impairment in ALS. In addition, C9orf72 (OR=5.94) and bulbar onset (OR=2.08) were strong predictors of ALS-frontotemporal dementia. Female sex conferred more susceptibility to executive cognitive impairment than male sex (OR=1.82).Conclusions Patients with C9orf72 repeat expansion, dysarthria, family history of ALS, PUMN phenotype and bulbar onset had a high risk for cognitive impairment in ALS. These associations may contribute to understanding the heterogeneity of ALS.PROSPERO registration number CRD42020201085.All data relevant to the study are included in the article or uploaded as online supplemental information. ER -