Participants with peptide levels in the highest quintile of NT-proBNP distribution were almost two times more likely to have reduced cognitive ability (lowest tertile of ‘g’) and were more than two times more likely to have possible clinical depression following the adjustment for age and sex, compared with the remaining population, but associations of NT-proBNP with ‘g’ and depression scores no longer reached statistical significance when diabetes-related and vascular co-variates were additionally controlled for. Here, NPPB is linked to depressive disorder.