Seventh Korea National Health Research Articles

Low dietary vitamin C intake is associated with low muscle strength among elderly Korean women

Although vitamin C is one of the most important antioxidants, its effect on muscle quality is not fully understood. Therefore, we hypothesized that low dietary vitamin C intake is associated with low muscle strength. To test the hypothesis, a single 24-h dietary recall and handgrip strength test of 10,883 younger adults 19-64 y and 3,961 older adults ≥65 y from the seventh Korea National Health and Examination Survey (KNHANES VII 2016-2018) was analyzed by multivariable linear and logistic regression models, and low muscle strength was defined as handgrip strength <28 kg for men and <18 kg for women. Approximately 15.5% of Korean adults met the recommended intake of dietary vitamin C, and those with higher dietary vitamin C intake had higher total energy and protein intake. After adjusting for confounding variables, including age, body mass index, total energy intake, household income, alcohol consumption, smoking, resistance exercise, medical condition, and dietary intake of protein, vitamin E, and β-carotene, dietary vitamin C was correlated with maximal handgrip strength in younger women 19-64 y (β = 0.002; SE = 0.001; P-value = .026) and older women ≥65 y (β = 0.005; SE = 0.002; P-value = .013). Among older women ≥65 y, those in the lowest quartile of dietary vitamin C intake had a higher risk of low muscle strength compared to those in the highest quartile after adjustment of confounding factors (odds ratio, 2.16; 95% confidence interval, 1.49-3.15). These results imply that adequate dietary vitamin C intake may reduce the risk of sarcopenia in older Korean women.

Inequality in dental flossing behavior among Korean adults based on household income levels.

The aim of this study was to estimate the association between household income and dental flossing. This cross-sectional study investigated the impact of household income on flossing among 9,391 adults aged 30+ with ≥20 natural teeth, utilizing data from the seventh Korea National Health and Nutrition Examination Survey (2016-2018). Outcome measures included flossing (yes/no), with income categorized into 4 levels: lowest, medium to low, medium to high, and highest. Logistic regression, adjusted for age, gender, brushing frequency, recent dental exams, periodontitis, smoking, and alcohol use, was employed to evaluate the influence of socioeconomic status on oral hygiene practices. In the highest income group, flossing was 62.6% more prevalent than in the lowest income group (adjusted odds ratio [aOR], 1.63; 95% CI, 1.27-2.08). The strongest association between income levels and flossing was observed in individuals aged ≥70 years (aOR, 3.64; 95% CI, 1.86-7.11), with a decreasing strength of association in the 60s (aOR, 1.72; 95% CI, 1.05-2.84) and 50s age groups (aOR, 1.69; 95% CI, 1.07-2.68). Higher-income women demonstrated a higher frequency of flossing than their lower-income counterparts (aOR, 1.67; 95% CI, 1.24-2.23). Higher-income individuals without periodontitis were more likely to floss (aOR, 1.64; 95% CI, 1.23-2.18), and among those with periodontitis, flossing was significantly associated only with the highest income category (aOR, 1.64; 95% CI, 1.10-2.44). The findings of this study indicate a significant correlation between higher household income levels and an increased prevalence of flossing.

An Explainable Prediction for Dietary-Related Diseases via Language Models.

Our study harnesses the power of natural language processing (NLP) to explore the relationship between dietary patterns and metabolic health outcomes among Korean adults using data from the Seventh Korea National Health and Nutrition Examination Survey (KNHANES VII). Using Latent Dirichlet Allocation (LDA) analysis, we identified three distinct dietary patterns: "Traditional and Staple", "Communal and Festive", and "Westernized and Convenience-Oriented". These patterns reflect the diversity of dietary preferences in Korea and reveal the cultural and social dimensions influencing eating habits and their potential implications for public health, particularly concerning obesity and metabolic disorders. Integrating NLP-based indices, including sentiment scores and the identified dietary patterns, into our predictive models significantly enhanced the accuracy of obesity and dyslipidemia predictions. This improvement was consistent across various machine learning techniques-XGBoost, LightGBM, and CatBoost-demonstrating the efficacy of NLP methodologies in refining disease prediction models. Our findings underscore the critical role of dietary patterns as indicators of metabolic diseases. The successful application of NLP techniques offers a novel approach to public health and nutritional epidemiology, providing a deeper understanding of the diet-disease nexus. This study contributes to the evolving field of personalized nutrition and emphasizes the potential of leveraging advanced computational tools to inform targeted nutritional interventions and public health strategies aimed at mitigating the prevalence of metabolic disorders in the Korean population.

Nutritional intake, environmental factors, and their impact on myopia prevalence in Korean children aged 5–12 years

BackgroundMyopia is a complex condition influenced by numerous factors, including genetic predisposition, environmental factors, and lifestyle choices. Although evidence indicates that certain dietary factors may influence the development of myopia, this relationship is still not completely understood and is a topic of ongoing research.MethodsThis study analyzed the relationship between dietary habits, environmental factors, and the prevalence of myopia in a sample of 24,345 children aged 5–12 years from the seventh Korea National Health and Nutrition Examination Survey (KNHANES VII). The average daily intake of dietary nutrients associated with the refractive error status of the participants was analyzed using analysis of variance (GLM) and the Scheffe method for post-hoc comparison. Multiple logistic regression analysis was conducted between the participant’s refractive error status and daily dietary nutrient intake, while taking into consideration the age, sex, BMI, parental myopia, and near-work hours.ResultsThe risk of myopia increased with age, especially notable between ages 11 and 12, and was higher in children with both parents having myopia. Dietary factors played a crucial role; children with myopia had significantly lower intake of fat, omega-3 fatty acids, and retinol but higher intake of other nutrients compared to emmetropic and hyperopic counterparts. High consumption of carbohydrates, protein, phosphorus, iron, potassium, and sodium was associated with increased myopia risk. High sodium intake was particularly associated with a 2.05-fold increased myopia risk.ConclusionsThis study highlights the significant role of diet and lifestyle choices in the development of myopia in children. Our findings suggest the importance of considering these specific factors in the management and prevention strategies for myopia, underscoring the need for targeted interventions in children's health and vision care.

Association between multimorbidity and periodontal disease in Korean adults: A nationwide cross-sectional cohort study.

This study aimed to investigate the association between multimorbidity, which refers to the presence of two or more chronic diseases, and periodontal disease in Korean adults using national survey data. A total of 12,440 Korean adults aged ≥19 years were selected from the seventh Korea National Health and Nutrition Examination Survey (KNHANES). We investigated periodontal disease status based on various variables, including the gender, age, educational level, income level, smoking and alcohol drinking status, frequency of daily toothbrushing, and unmet dental treatment needs. Furthermore, periodontal status according to diagnosed chronic diseases, including hypertension, dyslipidaemia, stroke, myocardial infarction, angina pectoris, and diabetes, was investigated, and the association between multimorbidity and periodontal disease was analysed through multiple logistic regression using SAS 9.4. According to the general characteristics of the study participants, the prevalence of periodontal disease was higher in males, smokers, older age, and lower educational and income levels (p < 0.001). Moreover, as the frequency of daily toothbrushing increased, the distribution of periodontal disease decreased (p < 0.001). The prevalence of periodontal disease was higher in those with chronic diseases than in those without chronic diseases and was statistically significantly higher as the number of diagnosed chronic diseases increased (p < 0.001). Additionally, an increase in the number of chronic diseases was observed to increase the prevalence and risk of periodontal disease. These results suggest that multimorbidity significantly affects the prevalence of periodontal disease.

Relationship between C-reactive protein level and periodontitis and systemic diseases.

Periodontitis affects systemic disease risk, although the relationship thereof in the context of different C-reactive protein (CRP) levels is not clear. This study investigated the association of periodontitis with systemic diseases according to high-sensitivity CRP (hs-CRP) level and sought to identify the risk of systemic diseases in patients with periodontitis. We used data from the seventh (2016-2018) Korea National Health and Nutrition Examination Survey. In a total of 16,489 subjects, the hs-CRP group was classified into the hs-CRP low-risk group and the hs-CRP high-risk group. Propensity score matching (PSM) is used for 1:1 matching of confounding variables (e.g., age, gender, income, and education) between hs-CRP low-risk and hs-CRP at-risk groups to analyze the final 5316 subjects. The association between general characteristics and prevalence of systemic diseases was analyzed using descriptive statistics and the chi-squared test. The associations between hs-CRP level and systemic and periodontitis were analyzed using logistic regression analyses. Within the hs-CRP group, the presence of periodontitis was associated with a significantly increased prevalence of hypertension, diabetes mellitus, and stroke. In the hs-CRP risk group, periodontitis significantly increased the risk of hypertension and diabetes mellitus by 2.1 and 2.4 times, respectively. The presence of periodontitis significantly increases the prevalence of systemic diseases and more so in individuals with higher hs-CRP levels. This indicates the significance of maintaining oral health in reducing the risk of systemic diseases.

Relationships of walking activity with depressed mood and suicidal ideation among the middle-aged Korean population: a nationwide cross-sectional study.

The suicide rate of middle-aged adults has increased rapidly, which is a significant public health concern. A depressed mood and suicidal ideation are significant risk factors for suicide, and non-pharmacological interventions such as exercise therapy have been suggested as potential treatments. Walking is a feasible and accessible form of exercise therapy for middle-aged adults. We conducted a study based on the Seventh Korea National Health and Nutrition Examination Survey (2016-2018) data of 6,886 general middle-aged adults in South Korea to investigate the relationships of walking exercise with depressed mood and suicidal ideation. Multiple logistic regression analysis was used to adjust for confounding variables. Sampling weights were applied to obtain estimates for the general Korean population. Participants who walked ≥5 days per week had a significantly lower odds ratio (OR) for depressed mood [OR = 0.625, 95% confidence interval (CI): 0.424-0.921, p = 0.018] and suicidal ideation (OR = 0.252, 95% CI: 0.125-0.507, p < 0.001) compared to those who never walked, regardless of the duration of exercise. The same results were obtained for males after stratifying the data by sex and suicidal ideation was associated with walking in females. Regular walking exercise was associated with diminished mental health problems in middle-aged adults. Light walks may serve as a useful starting point for patients with serious mental health issues, such as suicidal ideation.

Catch-up sleep on free days and body mass index: results from the seventh Korea National Health and Nutrition Examination Survey, 2016.

We aimed to identify the relationship between duration of categorized catch-up sleep on free days (CUS) and measured body mass index (BMI) in adults using the data from the seventh Korean National Health and Nutrition Examination Survey (KNHANES VII), 2016. CUS duration was classified as ≤ 0, > 0-1, > 1-2, and > 2 hours. Being overweight or obese was defined as having a BMI ≥ 25.0 kg/m2 or ≥ 30.0 kg/m2, respectively. Of 6,382 participants aged 19-80 years in the KNHANES VII survey of 2016, 201 and 583 participants were excluded because of shift-working and insufficient data, respectively. Of 5,598 participants, CUS was observed in 2,274 (44.9%) participants, of which 3,324 (55.1%), 1,043 (19.4%), 724 (14.7%), and 507 (10.8%) had CUS of ≤ 0, > 0-1, > 1-2, and > 2 hours, respectively; the prevalence of obesity was 5.6%, 5.6%, 4.8%, and 6.1%, respectively. The association between BMI and CUS duration showed a significant negative association in the CUS ≤ 0 hours group (beta [95% confidence interval], -0.394 [-0.646, -0.143], P = .002); however, other CUS groups did not show any significant association with BMI (CUS > 0-1 hours: -0.196 [-1.258, 0.865], P = .716; CUS > 1-2 hours, -0.542 [-1.625, 0.541], P = .325; CUS > 2 hours, -0.113 [-0.459, 0.233], P = .519). Our findings provide an understanding of the relationship between CUS and BMI and can serve as an instructive basis for the management of BMI. Lee HJ, Cho S, Lee SH, Kim SJ, Kim KM, Chu MK. Catch-up sleep on free days and body mass index: results from the seventh Korea National Health and Nutrition Examination Survey, 2016. J Clin Sleep Med. 2024;20(1):39-47.

Comparison of Weight Control Attempts among Middle-Aged and Older Women with Obesity: Findings Based on the Seventh Korea National Health and Nutrition Examination Survey (KNHANES VII-3)

Comparison of Weight Control Attempts among Middle-Aged and Older Women with Obesity: Findings Based on the Seventh Korea National Health and Nutrition Examination Survey (KNHANES VII-3)

Regional differences in the associations of diet quality, obesity, and possible sarcopenia using the seventh Korea National Health and Nutrition Examination Survey (2016-2018).

Sarcopenic obesity is closely related to aging and the prevalence of various chronic diseases and frailty. The purpose of this study was to analyze whether diet quality is related to obesity, sarcopenia, and sarcopenic obesity, and if so, to explore the difference in that relationship between urban and rural settings. Using data from the Korea National Health and Nutrition Examination Survey of 2016-2018, a total of 7,151 participants aged 40 years or older were analyzed. Sarcopenia was diagnosed using handgrip strength. Diet quality was assessed using Korea Healthy Eating Index (KHEI) scores, and obesity was determined based on participants' abdominal circumference. Multinomial logistic analysis was used for testing statistical significance. Rural participants had significantly lower KHEI scores and a higher prevalence of sarcopenic obesity than urban participants. The study findings demonstrate that participants without obesity, sarcopenia, or sarcopenic obesity had significantly higher KHEI scores in both rural and urban settings. Multinomial regression analysis further revealed that a higher KHEI score was associated with a lower risk of sarcopenia and sarcopenic obesity among urban residents, while only the risk of obesity was lower with higher diet quality scores among rural residents. Since diet quality and health status were lower in rural areas, it is important to address this regional disparity with appropriate policy measures. To mitigate urban health disparities, urban residents in poor health with few resources should also be supported.

Association of dietary sodium intake with impaired fasting glucose in adult cancer survivors: A population-based cross-sectional study.

Dietary sodium intake is a crucial lifestyle factor that should be assessed in adult cancer survivors due to their increased risk of adverse health outcomes compared to the general population. However, its with impaired fasting glucose (IFG) in adult cancer survivors remains unclear. This study aimed to investigate the association of dietary sodium intake categorized by the American Heart Association (AHA) recommendation with IFG in the community-dwelling adult cancer survivors. A total of 1,052 adult cancer survivors without diabetes were identified from the sixth and seventh Korea National Health and Nutrition Examination Survey (KNHANES), 2013-2018. Data on dietary sodium intake was categorized as <1,500 mg/day, 1,500-2,999 mg/day, 2,300-3,999 mg/day, and ≥4,000 mg/day according to the AHA recommendation. A multiple logistic regression model adjusted for demographic, lifestyle, and health status was used to compute odds ratios (OR) and 95% confidence intervals (95% CI) for IFG according to dietary sodium intake categories. After adjusting for confounding variables identified in the KNHANES, the adjusted OR among the adult cancer survivors who consumed 1,500-2,999 mg/day, 2,300-3,999 mg/day, and ≥4,000 mg/day of dietary sodium were 1.16 (95% CI: 0.25-5.27), 1.93 (95% CI: 0.40-9.37), and 2.67 (95% CI: 0.59-12.18), respectively, as compared to those who consumed <1,500 mg/day (P value for trend = 0.036). Among community-dwelling adult cancer survivors, high dietary sodium intake was marginally associated with increased odds of IFG. Well-designed cohort studies or randomized clinical trials are needed to establish more epidemiologic evidence on this association in adult cancer survivors.

Unique inverse association between allergic rhinitis and periodontitis: a nationwide population-based study

The increase in fine dust levels in the atmosphere has been associated with a growth in the incidence of environmental diseases, including allergic rhinitis (AR). Nasal obstruction caused by AR can impact the conditions in the oral cavity. The aim of this study was to determine the association between AR and periodontitis in the Republic of Korea. This study was based on data from the Seventh Korea National Health and Nutrition Examination Survey (KNHANES VII-1, 2016), which was conducted by the Korea Centers for Disease Control and Prevention. The study included 6129 adults older than 19 years. Sociodemographic information and medical variables including history of treatment of periodontitis (HTP) reflecting diagnosis of periodontitis and diagnosis of diseases such as AR were extracted from the data. HTP and AR were reported for 22.81 ± 0.84% (weighted percentage ± standard error) and 15.32 ± 0.63% of the studied population, respectively. A diagnosis of AR was reported for 11.07 ± 1.28% of those with HTP and for 17.55 ± 1.84% of those without HTP. From these, it was inferred that the prevalence of HTP was 1.536-fold higher in the non-AR group than in their counterparts with AR. Significant association was found between AR and HTP among those aged ≤ 64 years and the odds ratio (OR) of AR group for HTP was 0.62 (95% confidence interval:0.44–0.87; P = 0.0057). From this result, it can be inferred that patients diagnosed AR have lower risk of periodontitis.

Association between obesity and high-sensitivity C-reactive protein in Korean adults without cardiovascular disease

Purpose: This study aimed to investigate the association between obesity and high-sensitivity C-reactive protein (hs-CRP) levels in Korean adults without cardiovascular disease (CVD). Methods: The subjects were 3,634 adults, and data were extracted from the seventh Korea National Health and Nutrition Examination Survey (KNHANES Ⅶ-3). A complex sampling design analysis was applied to reflect the stratified and clustered weights. The data were analyzed using the complex sample Rao-Scott chi-square test and multiple logistic regression analysis (in SPSS for Windows version 26.0). Obesity, according to body mass index (BMI), was defined as obesity (BMI=25-29.9 kg/m²), high obesity (BMI=30-34.9 kg/m²), and super-high obesity (BMI≥35 kg/m²), and abdominal obesity (AO) was defined as a waist circumference (WC) ≥90 cm in males and WC ≥85 cm in females.Results: The odds ratios for moderate CVD risk (hs-CRP; 1-3 mg/dL) were 2.21, 4.16, and 7.13 in the obesity, high obesity, and super-high obesity groups, respectively, compared to the normal BMI group. The odds ratio for moderate CVD risk was 2.18 in males with AO and 1.88 in females with AO. The odds ratios for high CVD risk (hs-CRP&gt;3mg/L) were 4.40 and 17.55 in the high obesity and super-high obesity groups, respectively, compared to the normal BMI group.Conclusion: This study provides evidence that early detection and prevention programs for CVD should include obesity-related interventions aiming to modulate hs-CRP.

Obesity-Related Factors in Adult Women with Early Menarche.

The average menarche age among South Korean women has decreased over time. Early menarche in women causes a higher incidence of obesity owing to the continuous fat accumulation induced by prolonged exposure to estrogen and adrenal steroids. Identifying the factors affecting obesity in women who experience early menarche is essential for managing obesity in adult women. This study aimed to analyze the factors associated with obesity in adult women who experienced early menarche and to provide basic data for obesity management. This study was a cross-sectional and descriptive survey from the seventh Korea National Health and Nutrition Examination. A total of 371 women aged ≥ 19 years experienced early menarche, and the propensity matching method was used to analyze the obesity-related factors identified in previous studies. The results showed that obesity in adult women with early menarche was negatively associated with the level of aerobic exercise (OR = 0.53, 95% CI = 0.30-0.93, p = 0.028) and muscle-strengthening exercise (OR = 0.33, 95% CI = 0.17-0.64, p = 0.001). Future longitudinal studies on girls who experience early menarche are needed to address female obesity prevention at every stage of life, and, based on these findings, obesity management programs can be developed and applied and their effectiveness determined.

Development of a semi-quantitative food frequency questionnaire for dietary intake of elementary school children: data from the Seventh Korea National Health and Nutrition Examination Survey.

In Korea, studies of diet in elementary school children are hindered by the need for a comprehensive dietary assessment tool. Thus, the aim of this study was to develop a semi-quantitative food frequency questionnaire (FFQ) for Korean elementary school children. The 24-h recall data for 1,624 subjects aged 6-11 yrs from the seventh Korea National Health and Nutrition Examination Survey were used to extract the items included in the questionnaire. The FFQ items were developed by selecting major dishes based on the results of nutritional contribution and between-person variability for energy and 14 nutrients (carbohydrate, protein, fat, crude fiber, calcium, phosphorous, iron, sodium, potassium, vitamin A, thiamin, riboflavin, niacin, and vitamin C). We selected the major dishes with over 90% of the total contribution to each nutrient and with over 90% of the accumulated R2 for each nutrient. Among the 452 dishes, we selected 248 dishes contributing more than 1% of the total consumption. Finally, the FFQ included 107 items combined from 248 dishes based on nutrient profile and recipe. The FFQ items accounted for an average of 88.6% of the energy, 14 nutrient intakes, and 91.4% of the between-person variability. Quantities of dietary intake were assessed by 9 categories of frequency and 3 categories of portion size. Percentages of coverage for energy, protein, fat, carbohydrate, and calcium were 90.2%, 87.8%, 89.9%, 90.8%, and 88.7%, respectively. We developed a dish-based, semi-quantitative FFQ comprising 107 items for Korean elementary school children aged 6 to 11. Further studies are needed to evaluate the reproducibility and validity of this FFQ for elementary school children.

Association between seafood intake and frailty according to gender in Korean elderly: data procured from the Seventh (2016–2018) Korea National Health and Nutrition Examination Survey

Association between seafood intake and frailty according to gender in Korean elderly: data procured from the Seventh (2016–2018) Korea National Health and Nutrition Examination Survey

Factors Influencing the Eating Behaviors of Young Adults Using the 2013-2018 Korea National Health and Nutrition Examination Survey.

There is a substantial gap in the eating behaviors between the sexes. We aimed to analyze the predictors of eating behaviors by sex in the young adult population. We used the data of the sixth and seventh Korea National Health and Nutrition Examination Survey conducted by the Korea Disease Control and Prevention Agency last 2013-2018. Data from 2,502 women and 2,101 men aged 19-29 yr were included in the analysis using frequency, percentage, x 2-test, and multiple logistic regression. Education (0.612, CI=0.465∼0.805), economic status (2.104, CI=1.435-3.086), marital status (3.162, CI=2.356∼4.243), and household structure (0.403, CI=0.208∼0.782) were identified to predict the frequency of dining-out in women, while marital status (0.302, CI=0.121∼0.749), economic activity (1.969, CI=1.483∼2.613), and household structure (0.243, CI=0.137∼0.432) predicted dining-out frequency in men. The current smoking status predicted most eating behaviors, including breakfast skipping frequency (1.864, CI=1.318∼2.637), use of supplements (2.062, CI=1.439∼2.953), and use of nutrition labels (1.545, 1.084∼2.204) for men. Meanwhile, nutrition labeling was used less in both men (0.550, CI=0.343∼0.882) and women (0.646, CI=0.473∼0.882) who subjective body recognition as obesity. The factors that primarily predicted the frequency of dining out in young women and the behavior of breakfast skipping, use of nutrition labels, and frequency of dining-out in men can be used as foundational data for developing sex-specific intervention programs to improve eating behaviors.

Predictors of Depression among Individuals Receiving the Basic Livelihood Security Program Benefits in Korea: A Study Based on the Sixth and Seventh Korea National Health and Nutrition Examination Survey (2013-2018).

The purpose of this study is to verify the relationship between oral health behaviors and depression and influencing factors on depression to establish strategies that can contribute to improvement of mental health problems such as depression in vulnerable social class recipients. This study is a descriptive correlation study conducted on basic livelihood recipients over the age of 19 who responded to the 6th~7th (2013~2018) National Health and Nutrition Examination Survey. In this study, a total of 2749 people who met the criteria for subject selection were included in final analysis after requesting and downloading their raw data from the National Health and Nutrition Examination Survey through the consent process mandated by the Korea Centers for Disease Control and Prevention. Of the 2749 subjects, 279 were diagnosed with depression, accounting for 10.1% of the total. The collected data were analyzed using t-tests and chi-squared tests, and factors affecting depression were analyzed by logistic regression analysis. Our results showed that the factors affecting depression were 1.74 times for men (95% CI = 1.29-2.24), 1.37 times for older people (95% CI = 1.01-1.87), and 1.66 times for low education (95% CI = 1.21-2.27). Subjects with impairment in daily activities had 1.89 times (95% CI = 1.43-2.52) higher risk. Subjects with moderate physical activity and subjects with economic activity showed a lower risk (95% CI = 0.30-0.73) and 0.52 times (95% CI = 0.30-0.72), respectively, than subjects who did not. We confirmed that the probability of being diagnosed with depression decreased, and the perceived health status was 0.36 times lower (95% CI = 0.22-0.61) than those with good status. Therefore, it is necessary to prepare countermeasures that reflect various aspects in consideration of not only age and gender, but also daily life and emotional state when establishing policies for vulnerable classes such as recipients of basic livelihood.

Association between Amount of Alcohol Consumption and Serum Fasting Glucose Level in Korean Male in their 40s and 50s: The Seventh Korea National Health and Nutrition Examination Survey 2016-2018

Association between Amount of Alcohol Consumption and Serum Fasting Glucose Level in Korean Male in their 40s and 50s: The Seventh Korea National Health and Nutrition Examination Survey 2016-2018

Association Between Oral Health and Frailty in Older Korean Population: A Cross-Sectional Study.

Frailty is closely associated with biological age, concurrent medical conditions, morbidity, and decreased survival. Poor oral health is common in older individuals and is associated with frailty. Considering its potential importance, a study on the association between oral health and frailty is meaningful. Therefore, we aimed to analyze the association between major oral health factors and frailty using nationally representative samples of older adults. This cross-sectional study included 3018 older adults (age ≥ 65 years) from the seventh Korea National Health and Nutrition Examination Survey. Oral examination results, laboratory data, handgrip strength, life style factors derived from questionnaires, and food intake survey results were analyzed. This study used the deficit accumulation model among the main operational definitions of frailty. We constructed a frailty index based on 36 items and classified participants as non-frail, pre-frail, or frail. Oral health factors included chewing difficulty, number of teeth, periodontal disease, and number of carious teeth. Logistic regression analysis was performed to determine significant factors. A total of 1222 (40.5%), 1014 (33.6%), and 782 (25.9%) individuals were classified as non-frail, pre-frail, and frail, respectively. Chewing difficulty was associated with increased risk of frailty after adjusting for age, sex, socioeconomic factors, and comorbidities (odds ratio 2.68, 95% confidence interval 2.08-3.44). Periodontal disease was positively associated with chewing difficulty (odds ratio 1.29, 95% confidence interval 1.07-1.56), and chewing difficulty decreased as the number of teeth increased (odds ratio 0.97, 95% confidence interval 0.96-0.99). Chewing difficulty was significantly associated with frailty in the older population. Considering the negative effect of chewing difficulty on frailty, more attention should be focused on oral health.