Dental calculus is associated with death in heart infarction

Method: Prospective longitudinal cohort study. 1676 randomly selected healthy young Swedes followed up from 1985 to 2011.The subjects were selected from the registry file of all inhabitants of Stockholm County born on the 20th of any month from 1945 to 1954 (n=105 798).At the beginning of the study, all subjects underwent oral clinical examination and answered a questionnaire assessing background variables such as socioeconomic status and smoking. The Swedish national hospital admission, heart infarct- and death registers were used to record heart infarcts and deaths, death being the outcome measure  of the study. Causes of death were classified according to the WHO International Classification of Diseases. Unpaired t-test, Chi-square tests, and multiple logistic regressions were used.

Result: Of the 1676 participants, 2.8% had died during follow-up. Women died at a mean age of 61.5 (± 2.6 SD) years and men at 61.7 (± 2.6 SD) years. The difference in the amount of calculus on teeth between those who died versus survivors was significant (p=0.015). In multiple regression analysis of the relationship between death in heart infarction as a dependent variable and several independent variables, calculus appeared to be associated with 2.3 times the odds ratio for death (p=0.038).

Conclusion: Our study hypothesis was confirmed. Dental calculus associates with premature death in heart infarctions. Namely, consistently high calculus index might be a proxy for infection burden from the oral cavity; up-regulating systemic reactions that may lead to death in heart infarctions.

Supported by Ministry of Health and Social Affairs (grants F84/189), and Karolinska Institutet, Stockholm, Sweden, The Finnish Medical Society, Helsinki, and by grant TI020Y0003 by the Helsinki University Central Hospital, Finland