• Tr-I, ALT, AST, LDH, and CK significantly higher in smokers than healthy group • Tr-I, CK, and LDH significantly ↑ in smoker/periodontitis vs. non-smoker/periodontitis • Cardiac biomarkers ↑ during periodontitis and their expression is further aggravated in conjugation with smoking. This evidence concerns the gene GPT and periodontitis.