Introduction

Metabolic syndrome was prevalent and increasing worldwide. Metabolic syndrome, the serious health problem resulted in cardiovascular disease, consists of hypertension, glucose intolerance, abdominal obesity, hypertriglyceridemia and low HDL cholesterol. Oral health factors, the major indicator of quality of life (Cervino, 2019), were reported to being associated with metabolic syndrome (Kaur, 2019). Gender disparities were also reported to be related with metabolic syndrome (Kim, 2019) the relationship between metabolic syndrome and healthy lifestyle factors (Hoyas & Leon-Sanz, 2019; Lin, 2019). Coping style and occupational stress were reported to be associated with periodontitis among workers by the cross-sectional study (Islam, 2019). Circulation microparticles in metabolic syndrome with cardiovascular risks were reported to be associated with oxidative stress (Zahran, 2019). Post traumatic stress was reported to be related with metabolic syndrome especially in women (LIhua, 2020). In current evidence on natural agents, they were reported to be on thoughtful perspective in oral health including periodontitis (Flores, 2019). It was reported on the links that serum vitamin C and antioxidant levels were related with periodontitis (Isola, 2019; Velden, 2020).

Especially, the relationship between vitamin D level and metabolic syndrome was suggested as important one in obese patient as well as general people for reducing metabolic disease and increasing longevity (Moukayed & Grant, 2019). Dietary nitrate was also reported to be associated with activating of metabolic pathways and reducing of oxidative stress (Lundberg, 2018). Dietary supplements such as botanical oil and fish oil was reported to be related with metabolic syndrome as well as type-2 diabetes (Lee, 2014).

In addition to that, dietary supplementation of watermelon juice was reported to being ameliorating the metabolic syndromes in obese animals (Wu, 2007) though it has kinds of some limitation in animal subjects. And more, oral health was reported to be closely connected with improving of overall health especially among adults (Ismail, 2019; Rawal, 2019; Uloma, 2019). In addition to that number of teeth, as the important indicator of oral health, was reported to increase the risk of metabolic syndrome among elderly (Pedro, 2019). Additionally, diabetes and smoking were closely associated with poor oral health such as tooth loss by recent cohort study (Kim, 2019). Through reviewing of current studies, we investigated to find out the major influencing factors of metabolic syndrome and impacting factors of oral health of 50 and older aged Koreans using nationally representative data of 6th Knhanes. Considering potential impact on subjects and lifestyle, we included demographic, socioeconomic, health related and oral health factors.

Materials and Methods

Using derived from nationally representative data from 6th Knhanes (Korea National Health and Nutrition Examination Survey), of stratified sampling one, after exclusion of missing and not available one, this study was analyzed. The standards of NCEP-ATP (National Cholesterol Education Program Adult Treatment Panel) for the criteria of metabolic syndrome was used for the study. This study is a cross-sectional designed one.

Study-subjects

This study was conducted to find out on relationship

between oral health and metabolic syndrome of 2433 consented participants, 50 aged and older, using complex-sampling-methods by multiple-logistic-regressions with SPSS (ver. 21.0).

Study-analysis

This study was analyzed by complex sampling methods. For the general characteristic of the 2433 subjects of aged 50 and over, demographic statistics methods were used. And chi-square test was used for analyzing prevalence of association between metabolic- syndrome and determinant factors. To investigate influencing factors of metabolic- syndrome and impact of oral health, multi-variable logistic regression methods with SPSS (ver. 21.0) were used. The significance- level was (p<.05).

Results and Discussion

Out of 2433 participants, 42.0% were men Table 1. 50-64 aged group was 52.2%. The prevalence of metabolic syndrome was 13.6%. About 30.2% participants reported no-taking of dietary supplements. 73.2% participants had stress. The lowest educational group (elementary) was 42.9%. Around 38.1% participants had periodontitis. Table 2 show prevalence of association between metabolic syndrome and determinant factors with impact of oral health among Korean 50 and older adults. The prevalence of metabolic- syndrome was 55.7% (men) and 44.3% (women). Prevalence of metabolic syndrome was showed as smoking (50.3%), yes feeling stress (64.5%), not taking dietary supplements (35.5%), and periodontitis (45.5%).

Table 3 depicts the major determinants of metabolic syndrome and the impact of oral among Korean 50 and over aged adults. By multivariable logistic regression explained that gender (male) (OR1.86;95%CI:1.27-2.72; p<.05), not taking dietary supplements (OR1.74;95%CI:1.22-2.48; p<.05) factors were the strongest one of metabolic syndrome. The next determinant factors were presence of stress (OR1.59;95%CI:1.28-1.98; p<.05), lowest education level (OR1.48;95%CI:0.98-2.21; p<.05), oral health factor (periodontitis) (OR1.39; 95%CI: 1.09-1.78; p<.05), were the major determinants of metabolic syndrome respectively. While the related smoking and drinking factors were showed as not associated one with no significance.

These findings suggest that men compared to women, not taking of dietary supplements, much stress, lower education level and periodontitis, as the indicator of oral health, were the major determinants of metabolic syndrome with analyzing 2433 participants aged 50 and older participants of the 6th Korea National Health and Nutrition Examination Survey. The prevalence of metabolic syndrome was 13.6%. This prevalence of metabolic syndrome result was low compared to that of another study (Kim, 2018) and these results were thought to be due to the total prevalence regardless of gender. Regarding gender (male), which was found to be the strongest factor of metabolic syndrome in this study, was mainly having common with the results of other studies even though they had some difference in age of participants (Jang & Kim, 2019; Kim, 2018).

But it was not consistent with the results of another studies in case of post-traumatic stress of women who had more metabolic risk (LIhua, 2020) and having more metabolic risks in female nurses by an observational study (Chico-Barba, 1993). With key regard to dietary supplements, as identified as one of the strongest factor of metabolic syndrome through this study, they have been identified to influence on the metabolic syndrome in several studies (Lee, 2014; Moukayed et al., 2019). In addition to that, the cardio-metabolic effect of dietary nitrate was reported to be very critical in the point of view of including mitochondrial respiration in health and disease as well as metabolic effects (Lundberg, 2018). And the results of this present study on the association between natural agents and oral health like periodontal health were supported by current studies (Flores, 2019; Isola, 2019).

Concerning stress, which was identified as the determinant factor of this study, that result was supported in some aspects by another studies (LIhua, 2020; Zahran, 2019). Especially, high stress was also known as being associated with taking the risk of periodontitis (Islam, 2019). 50-64 aged group compared to 65 and older group was more in being risk of metabolic syndrome of this study and this result was supported by another study (Pedro, 2019). In the point of view of periodontitis, as a key indicator of oral health, which was identified as the strong influencing factor of metabolic syndrome of this study, was partially in consistent with the result of another study even though there are difference in the aspects of racial sample and study design (Uloma, 2019) and it was supported by another study which was reported on association between oral health and metabolic syndrome among elderly (Pedro, 2019) even though the difference in gender. And that, even the awareness and habits of oral care was reported to be contributed to improving of life satisfaction as well as lifestyles of the elderly (Hirano, 2019). Poor oral health like periodontitis was shown to be seriously related with diabetes, one of the metabolic components (Rawal, 2019) including peripheral vascular disease and these results were partially consistent with our results (Wang, 2019). Moreover, periodontitis was reported to be associated with occupational stress and low coping condition (Islam, 2019).

Chewing, which was related with tooth loss causing of worsening cognition (Lee & Choi, 2019; Zahran, 2019) was already identified as the indicator of good oral health (Kim, 2019; Natarajan, 2019) even though it was not significant in this study. In view of education level, as the indicator of socioeconomic status, it was suggested the major factor of metabolic syndrome through this study, that was supported by another study which was reported on the close relationship between education level, alcohol consumption and physical activity and metabolic syndrome (Kim, 2018). Smoking and alcohol consumption which were known as the important factors of metabolic syndrome even though they were not significant in this study, were not consistent with the results of other study despite common results in the aspects of education level, and they seem to because of gender difference by study design (Kim, 2018).

The strength of this study was based on the nationally representative data with stratified survey in the point of reliability and validity. Major consideration of this study was including and dealing with the importance of the oral health variables such as chewing level and periodontitis as the critical role of potential and influencing on general health of middle older adults. The limitation of this study is in cross-sectional nature design. To conclude, gender (male), not taking of dietary supplements, stress as the psychological factor, lower education level and periodontitis as the indicator of oral health were the influencing major determinants of metabolic syndrome. So, public health professionals might be needed to manage the education strategies considering age, gender disparities, education level and promoting oral health to prevent metabolic syndrome. Further researches might be necessary to explore the mechanisms for validity between metabolic syndrome and oral health by gender to prepare early public and nursing interventions in this population.

Conclusions

In conclusion, it was suggested that gender(male) and not taking of dietary supplements were the major determinants of metabolic syndrome. And then, the next determinant factors were stress of the psychological status, elementary school in lowest education level and periodontitis in oral health were the important determinants of metabolic syndrome respectively. Therefore, public health and nursing professionals might urgently consider managing the public education strategies heightening on age, gender disparities, dietary habits and improving oral health as well as including to prevent metabolic syndrome. Continued researches should be accomplished to find out the links and associations of metabolic syndrome and dietary habits, psychological areas as well as oral health by gender for the future successful ageing.

Funding Support

The authors declare that they have no funding support for this study.

Conflict of Interest

The authors declare that they have no conflict of interest.