Meta-analysis of the endogenous N200 latency event-related potential subcomponent in patients with Alzheimer's disease and mild cognitive impairment

•Severe prolongation of N200 latency measurements was observed in patients with Alzheimer's disease compared to normative aging.•There was no statistically significant difference found in N200 latency measurements in studies comparing patients with mild cognitive impairment and patients with Alzheimer's disease.•The alterations in the N200 latency subcomponent may be sensitive enough to detect longitudinal changes in cognitive decline in elderly individuals.

ObjectivesThe N200 latency subcomponent has the potential to be an accurate neurophysiological marker of the cognitive deterioration seen in Alzheimer's disease (AD) and mild cognitive impairment (MCI).MethodsStandard mean difference (SMD) estimates of the N200 latency subcomponent were compared in three treatment groups: patients with AD, patients with MCI, and an unrelated elderly control group.ResultsPatients with AD had significantly prolonged N200 latencies compared to the control group, pooled SMD: 0.866 (95% CI: 0.517 to 1.214, z = 4.87, p < 0.001). Patients with MCI had significantly prolonged N200 latencies compared to the control group, pooled SMD: 0.578 (95% CI: 0.213 to 0.943, z = 3.31, p = 0.002). When comparing patients with AD and MCI the N200 latencies were similar, pooled SMD: 0.096 (95% CI: −0.261 to 0.453, z = 0.53, p = 0.598).ConclusionThe abnormalities present in the N200 latency subcomponent validate previous research that N200 latency is an informative indicator of information-processing deterioration in patients with cognitive impairment.SignificanceClinically, measurements of N200 latency can be used as a risk assessment of elderly patients that may be progressing to mild cognitive impairment and/or Alzheimer's disease.