Impact of Unreplaced Lost Teeth on Blood Pressure: An Evaluation of Health Checkup Data

Although positive relationships between tooth loss and cardiovascular disease have been extensively reported, the impact of tooth loss left unreplaced for a certain period on cardiometabolic conditions remains unclear. Thus, we aimed to evaluate the effects of unreplaced tooth loss with cardiometabolic markers in middle-aged bankers using data obtained from health checkups conducted at 2 age points with a 4-year interval. A total of 218 bankers aged 46 years with unreplaced teeth after loss 4 years prior (at age of 42 years) were analyzed. The health checkup included a physical examination, collection of blood specimen for laboratory test, a self-administered questionnaire regarding health behaviors, and a dental examination. Participants were categorized into 2 groups; those who had unreplaced tooth loss (UTL) and those who did not. Differences in mean values for systolic and diastolic blood pressure, high-density lipoprotein cholesterol and triglycerides, fasting blood glucose, and HbA1c between the groups were evaluated using analysis of covariance. A logistic regression model was constructed to calculate the odds ratio of the relation of UTL with high blood pressure (BP) (systolic BP ≥130 mmHg and/or diastolic BP ≥85 mmHg) including covariates. We found that higher levels of both systolic and diastolic BP were observed in participants with UTL than in those without (123.4 vs. 119.4 mmHg, and 75.9 vs. 71.9 mmHg, respectively), with a statistical significance in mean value for diastolic BP (P<0.01). In addition, participants with UTL had greater odds for high blood pressure, after adjusting for the covariates (adjusted odds ratio = 2.58 [1.25-5.35]). While, there were no significant differences in regard to the mean values for high-density lipoprotein cholesterol, triglycerides, fasting blood glucose, and HbA1c between the groups. Our results suggest that tooth loss left unreplaced for a certain period is related to increased BP levels in this early middleaged population. on cardiometabolic conditions was not examined. Thus, we hypothesized that individuals with unreplaced tooth loss (UTL) have worse cardiometabolic conditions such as high blood pressure (BP), glucose, and lipid metabolism disorder as compared to those without, and that a certain period of time is needed before the effect of UTL on cardio-metabolic conditions appears in clinical findings. To test our hypothesis, a long-term randomized clinical trial in which individuals with lost teeth are randomly assigned to a “replacement treatment” group or a “no treatment” group would be ideal. However, such studies are difficult to conduct based on ethical perspective. Thus, we obtained data from health checkups conducted at 2 age points with a 4-year interval, and evaluated the effects of UTL on cardiometabolic markers in middle-aged bankers. Materials and Methods The present study was a continuation of our previous work [16], which was performed using secondary data obtained from health checkups conducted at a large bank company in Japan. Although the Industrial Safety and Health Law of Japan require employers to provide annual medical checkups to employees, dental checkups are not required by the law. Bankers of the present company were eligible to receive dental checkups at the ages of 42 and 46 years. All participant annually had regular checkup and showed negligible cardiovascular defect symptoms. Figure 1 illustrates the flow of participants in the study. The study population consisted of bankers who participated in health checkup examinations from January 2006 to December 2011. Of the 3554 participants who underwent dental checkup at the age of 46 years, we analyzed data from 278 who had tooth loss 4 years prior (at the age of 42 years) that was unreplaced. Data for 60 were excluded because of a medical history that included hypertension, dyslipidemia, or hyperglycemia. Thus, findings for 218 participants were used for analysis. This study was approved by the Ethics Committee of Osaka University, Graduate School of Dentistry (H24-E18), and the requirement of written informed consent from each participant was waived by the ethics committee. The health checkups were conducted at health support centers of Miki Ojima1*, Atsuo Amano1 and Shu Kurata2 1Department of Preventive Dentistry, Osaka University Graduate School of Dentistry, Suita, Japan 2Dental Clinic, Osaka Health Support Center, Sumitomo Mitsui Banking Corporation, Osaka, Japan *Address for Correspondence Miki Ojima, Assistant Professor, Department of Preventive Dentistry, Osaka University Graduate School of Dentistry, 1-8 Yamadaoka, Suita, Osaka 565-0871, Japan, Tel: +81-6-6879-2922; Fax: +81-6-6879-2925; E-mail: ojima@dent.osaka-u.ac. jp Submission: 19 September 2015 Accepted: 19 October 2015 Published: 20 October 2015 Copyright: © 2015 Ojima M, et al. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. Research Article Open Access Journal of Oral Biology