Open Access Open Badges Research article

Diabetes severely affects attentional performance after coronary artery bypass grafting

Jens-Holger Krannich1*, Therese Tobias2, Jens Broscheit2, Rainer Leyh1 and Wolfgang Müllges3

Author Affiliations

1 Department of Cardiothoracic Surgery, University Hospital Würzburg, Oberdürrbacherstraße 6, Würzburg, 97080, Germany

2 Department of Anesthesiology, University Hospital Würzburg, Oberdürrbacherstraße 6, Würzburg, 97080, Germany

3 Department of Neurology and Comprehensive Heart Failure Center, University Hospital Würzburg, Josef-Schneider-Straße 12, Würzburg, 97080, Germany

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Journal of Cardiothoracic Surgery 2012, 7:115  doi:10.1186/1749-8090-7-115

Published: 6 November 2012



Diabetes is a risk factor for (micro) vascular damage of the brain, too. Therefore cognitive performance after coronary artery bypass grafting may be hypothesized worse in diabetics. To avoid observational errors a reliable tool for testing attentional performance was used. We evaluated whether diabetes mellitus disposes to distinct cognitive dysfunction after coronary artery bypass grafting (CABG).


Three aspects in attentional performance were prospectively tested with three different tests (alertness: composed of un-cued and cued reaction, divided attention, and selective attention) by a computerized tool one day before and seven days after CABG in a highly selected cohort of 30 males, 10 of whom had diabetes. Statistical comparisons were done with analysis of variance for repeated measurements and Fisher's LSD.


Prior to CABG there was no statistically meaningful difference between diabetics and non-diabetics. Postoperatively, diabetic patients performed significantly worse than non-diabetics in tests for un-cued (p=0.01) and cued alertness (p=0.03). Test performance in divided attention was worse after CABG but independent of diabetes status. Selective attention was neither affected by diabetes status nor by CABG itself.


Diabetes may have an impact on cognitive performance after CABG. More severe deficits in alertness may point to underlying microvascular disease.

Diabetes; Coronary artery bypass graft; Cognitive; Attentional performance