Oral status and homebound status: A 6-year bidirectional exploratory prospective cohort study

Association Between Oral Malodor and Dementia: An 11-Year Follow-Up Study in Japan

Background

As infrequent social interaction is a potential risk of dementia, oral malodor may increase the risk of dementia, including Alzheimer's disease.

Objective

This study investigated the association between malodor and dementia.

Methods

We used the Japan Public Health Center-based Prospective Study data obtained at Yokote City. A total of 1,493 individuals aged 56 to 75 years underwent a dental examination and self-reported survey from May 2005 to January 2006. Follow-up for the onset of dementia was conducted using long-term care insurance data from 2006 to 2016. Hazard ratios of oral malodor on dementia were estimated by the Cox proportional hazards model. The inverse probability-weighted Cox model was used as a sensitivity analysis.

Results

The study comprised 1493 participants (53.6% women) with a mean age of 65.6 (SD = 5.8) years old; at the end of the follow-up, 6.4% (n = 96) developed dementia, and the percentage was 20.7 in severe malodor group. Throughout 15274.133 person-years of follow-up, the average incidence rate for the onset of dementia per 1000 person-years was 6.29. The highest incidence rate was seen in participants with severe malodor (22.4 per 1000 person-years). After adjusting for confounders, compared to those with no malodor, there was a 3.8 (95% confidence interval: 1.5 to 9.4) times greater hazard of developing dementia in participants with severe malodor. The inverse probability weighted Cox model confirmed the same trend with an adjusted marginal hazard ratio of 4.4 (1.2 to 16.4).

CONCLUSIONS

A significant association between oral malodor and the onset of dementia exists.

Frequency of Going Outdoors and Risk of Poor Oral Health Among Older Japanese Adults: A Longitudinal Cohort From the Japan Gerontological Evaluation Study

BACKGROUND

The association between the frequency of going outdoors and the risk of poor oral health has been reported in several studies; however, the findings have been inconclusive.

METHODS

We conducted a 3-year longitudinal study of 19,972 Japanese adults aged ≥65 years who reported no poor oral condition at baseline in 2013. The respondents rated their frequency of going outdoors in three categories (≤1, 2-3, or ≥4 times/week), and the oral conditions reported in 2016 included tooth loss, chewing difficulty, swallowing difficulty, dry mouth, and composite outcomes. The associations between the frequency of going outdoors and the risk of poor oral health were examined as relative risk ratios (RRs) and 95% confidence intervals (CIs) using multivariable Poisson regression, while mediation analysis was performed to investigate indirect effects.

RESULTS

During the follow-up, 32.5% of participants developed poor oral health. In the mediation analysis, indirect effects were observed through low instrumental activities of daily living, depressive symptoms, little social network diversity, and underweight. Compared to going outdoors ≥4 times/week, the multivariable RRs of composite poor oral health conditions were 1.12 (95% CI, 1.05-1.20) for 2-3 times/week and 1.22 (95% CI, 1.07-1.39) for ≤1 time/week (P-trend < 0.001). Similar associations were observed for tooth loss, chewing difficulty, and swallowing difficulty; the corresponding RRs were 1.07 (95% CI, 0.97-1.19) and 1.36 (95% CI, 1.13-1.64) (P-trend = 0.002), 1.18 (95% CI, 1.06-1.32) and 1.30 (95% CI, 1.05-1.60) (P-trend < 0.001), and 1.15 (95% CI, 1.01-1.31) and 1.38 (95% CI, 1.08-1.77) (P-trend = 0.002), respectively.

CONCLUSION

The frequency of going outdoors was inversely associated with the risk of poor oral health through several modifiable risk factors in the older population.

Association of Stressful Life Events With Oral Health Among Japanese Workers

BACKGROUND

Psychological stress can cause various mental and physical health problems. The previous results on stress and oral health are inconsistent, possibly because of the narrow stress measurements. We aimed to examine the association between a broader range of stressful life events and oral health among workers.

METHODS

This cross-sectional study analyzed anonymous individual data from a national survey in Japan. Data on stressful life events, oral health problems which are one or more of tooth pain, gum swelling/bleeding, and difficulty chewing, and covariates were obtained using a self-reported questionnaire. Covariates used included gender, age group, and disease under treatment. Logistic regression analysis was used to estimate the association between stressful life events and oral health problems. We then estimated the causal treatment effects of stress using the augmented inverse-probability weighting (AIPW) method.

RESULTS

Among the 274,881 subjects, 152,850 men (55.6%) and 122,031 women (44.4%) with a mean age of 47.0 (standard deviation, 14.4) years, 4.0% reported oral health problems, with a prevalence of 2.1% among those without any stress. The prevalence increased with stress score, reaching 15.4% for those with the maximum stress score. The adjusted odds ratio of this group compared to those without any stress was 9.2 (95% confidence interval [CI], 8.2-10.3). The estimated prevalence of oral health problems by the AIPW analysis was 2.2% (95% CI, 2.1-2.3%) for those without any stress and 14.4% (95% CI, 12.1-16.7%) for those with the maximum stress scores.

CONCLUSION

There was a clear dose-response association between stressful life events and oral health problems.

Social support and oral health among working-age and older adults in the United States

OBJECTIVES

The purpose of this study was to examine the association of social support with untreated dental caries and severe tooth loss in adults in the United States.

METHODS

This cross-sectional study was conducted by analyzing data obtained from 5,447 individuals, 40 years of age and older, in the National Health and Nutrition Examination Survey (NHANES) from 2005 to 2008 who had both a complete dental examination and social support index measures. Sample characteristics, overall and by social support level, were examined through descriptive statistical analyses. Logistic regression analyses were performed to estimate the association of social support with untreated dental caries and severe tooth loss.

RESULTS

In this nationally representative sample (mean age 56.5 years) the prevalence of low social support was 27.5%. The prevalence of individuals with moderate-to-high social support increased with higher levels of educational attainment and income level. In fully adjusted models, relative to those who had moderate-high social support levels, individuals with low social support had 1.49 higher odds of untreated dental caries (95% CI, 1.17-1.90, p=0.002) and 1.23 higher odds of severe tooth loss (95% CI, 1.05-1.44, p=0.011).

CONCLUSIONS

Higher odds of untreated dental caries and severe tooth loss were found among U.S. adults with low levels of social support compared to those with moderate-to-high levels of social support. Additional studies are warranted to provide a more current perspective on the impact of social support on oral health so that programs may be developed and tailored to reach these populations.

Social Isolation/Loneliness and Tooth Loss in Community-Dwelling Older Adults: The Sukagawa Study

Background and Objectives

The relationship between social isolation/loneliness and oral health is unclear. This study investigated the association between social isolation/loneliness and tooth loss in older Japanese adults.

Research Design and Methods

This was a cross-sectional study of a population-based cohort (the Sukagawa Study); 5,490 cohort study participants aged ≥75 years and who were independent answered a self-administered questionnaire in 2018. Social isolation was defined based on the 6-item Japanese version of the Lubben Social Network Scale. Loneliness was measured by the 3-item Japanese version of the University of California, Los Angeles (UCLA) Loneliness Scale version 3. The primary outcome was tooth loss, defined as having fewer than 20 teeth. The secondary outcomes were decreased toothbrushing frequency and diminished ability to chew food. Prevalence ratios (PRs) were estimated using a modified Poisson regression analysis in 2 models-Model 1, which adjusted for age, gender, smoking status, alcohol consumption, low annual income, and short education period, and Model 2, which added history of depression, history of diabetes mellitus, history of stroke, and cognitive impairment to Model 1.

Results

The primary analysis included 4,645 participants. Adjusted PRs of social isolation and loneliness for tooth loss (Model 1) were 0.97 (95% confidence interval [CI] 0.92-1.01) and 1.06 (95% CI 1.01-1.12), respectively; those for decreased toothbrushing frequency were 1.13 (95% CI 0.95-1.36) and 1.56 (95% CI 1.26-1.92), respectively; and those for chewing difficulty were 1.61 (95% CI 1.06-2.43) and 2.94 (95% CI 1.91-4.53), respectively. The adjusted PRs in Model 2 demonstrated results similar to that of Model 1.

Discussion and Implications

Loneliness is associated with tooth loss among older adults, whereas social isolation is not. Our findings can inform plans for policymakers, professionals, and organizations to identify lonely older adults and provide social prescriptions to improve their access to oral health care services.