The Alzheimer-E. coli Axis: What Can We Learn from an Electronic Health Record Platform

Alzheimer's disease (AD) is a neurodegenerative disease with unclear etiology. Recent studies have demonstrated a potential role for gut microbiome. There is, however, a significant dearth in epidemiological correlation between gut bacteria and AD.

To investigate the association between Escherichia coli (E. coli) infection and AD.

Counts of patients with ICD 10 diagnoses of AD, E. coli, urinary tract infection, and comorbidities were retrieved from the electronic health records at the University of Florida Health Center.

The relative risk for AD with a previous event of E. coli was 5.17 (95%CI 4.0786 to 6.5446, p < 0.0001). In the unadjusted association, patients with E. coli infection had odds ratio (OR) of 20.83 to have AD (95%CI, 17.7-24.34; p < 0.0001); after adjusting for gender (OR = 12.71; 95%CI, 10.82-14.83; p < 0.0001), race (OR = 13.97; 95%CI, 11.84-16.36; p < 0.0001), age group (OR = 11.51; 95%CI, 9.73-13.54; p < 0.0001), diabetes (OR = 9.23; 95%CI, 7.79-10.87; p < 0.0001), stroke (OR = 5.31; 95%CI, 4.47-6.28; p < 0.0001), and hypertension (OR = 4.55; 95%CI, 3.86-5.32; p < 0.0001).

These results should be taken cautiously. This retrospective cross-sectional study cannot infer causality and had used aggregate data that did not allow simultaneous adjustments of covariates. Future studies are warranted to investigate the link between gut bacteria and AD.