Supplementary Material for: Contemporary Incidence of Cognitive Impairment or Dementia in Patients undergoing Coronary Artery Bypass Grafting: A Systematic Review and Meta-analysis

Introduction: Despite the high prevalence of cognitive impairment or dementia post coronary artery bypass grafting (CABG), the incidence of cognitive impairment or dementia post-CABG in contemporary practice is currently unclear. Therefore, this paper aims to investigate the incidence and associated risk factors of cognitive impairment or dementia in patients post-CABG.

Methods: A systematic search across three databases (PubMed, SCOPUS and Embase) was conducted for studies published in or after 2013 that reported cognitive impairment or dementia post-CABG. Subgroup analyses and meta-regression by risk factors were performed to determine their influence on the results.

Results: This analysis included 23 studies with a total of 2620 patients. The incidence of cognitive impairment or dementia less than one month, two to six months, and more than twelve months post-CABG was 35.96% (95%CI: 28.22-44.51, I2=87%), 21.33% (95%CI: 13.44-32.15, I2=88%) and 39.13% (95%CI: 21.72-58.84, I2=84%), respectively. Meta-regression revealed that studies with more than 80% of the cohort diagnosed with hypertension were significantly associated with incidence of cognitive impairment or dementia less than one-month post-CABG.

Conclusion: This meta-analysis demonstrates a high incidence of cognitive impairment or dementia in patients post-CABG in contemporary practice, particularly less than one month post-CABG. We found that hypertension was a significant risk factor in the short term (less than one month) follow-up period for cognitive impairment or dementia post-CABG. Future research should be done to assess strategies to reduce cognitive impairment post-CABG.