The role of periodontitis in cardiovascular disease

Abstract: Periodontitis and cardiovascular disease (CVD) are both common diseases affecting a large part of the society. Both diseases are considered to have a chronic inflammatory origin. During the last decades research has focused on a possible link between them. Most of these studies have examined the epidemiological relationship between periodontal disease and CVD. The biological reason for a link has been discussed, but is unclear. In this thesis an association between periodontal disease and CVD the diseases in an adult Swedish population have been studied, and several biological risk factors related to atherosclerosis in periodontitis patients investigated. The first aim of these studies was to investigate if there was a connection between the inflammatory diseases, atherosclerosis and periodontitis, in an adult Swedish population (paper I, III), and if this connection also was found in a female population (paper IV). Secondly we wanted to investigate the mechanism behind it, if a connection was established (paper V). The third aim of these investigations was to investigate if self-reported questionnaires of oral health were reliable in health surveys (paper II). The fourth and final purpose of this thesis was to investigate the oral health status in Swedish population and peoples attitudes towards oral and dental health (paper III). Paper I and paper III showed that there was a relationship between self-reported CVD and bleeding gums, and other oral health parameters in an adult Swedish population. Paper II demonstrated that self-assessment of oral status was a valid method for determining the number of remaining teeth and the use of removable dentures. However, questionnaires were found to be less reliable for specific periodontal variables such as tooth movability, but could still be developed into a valuable tool in epidemiological studies of periodontal health. In paper III, a large proportion of a Swedish suburban adult population was shown to have had dental problems without seeking help, partly for financial reasons. This group was also more likely to have cardiovascular disease and bleeding gingiva. Paper IV demonstrated that women with coronary heart disease (CHD) had worse oral conditions compared to women with no history of CHD. This could indicate a link between the presence of periodontal inflammation, poor oral health and the presence of atherosclerosis. In paper V several serological differences were found between subjects with and without periodontitis, some of which involved established risk factors for atherosclerosis (lipid profile, high density lipoproteins (HDL), C reactive protein (CRP), interleukin 6 (IL 6), and immune globulin A anti-human heat-shock 60 (IgA anti-human Hsp 60)). These findings might offer an etiological explanation for the epidemiological association between periodontitis and cardiovascular disease. In conclusion These studies show that there is an association between CVD and signs of periodontal disease in a Swedish adult population. The studies also show that certain serological risk-markers for atherosclerosis are increased and that HDL is decreased in patients with periodontal disease. Although the clinical implications of these findings remain unknown, these findings could provide one possible explanation for the relationship between the two diseases. The thesis also demonstrated that self-reported questionnaires could potentially be used to assess oral health and treatment needs in large populations.