Cultural engagement and prevalence of pain in socially isolated older people: a longitudinal modified treatment policy approach.

Background: It remains uncertain whether cultural engagement positively influences the reduction of pain risk, particularly depending on the social isolation status. The aim of this study was to examine the impact of cultural engagement on the reduction of pain prevalence over a 6-year follow-up period among older people, particularly those experiencing different dimensions of social isolation. Methods: This study was a prospective longitudinal study. We analysed the English Longitudinal Study of Ageing cohort, consisting of 6468 community-dwelling adults aged ≥50 years old who provided data in waves 6 (2012-2013), 7 (2014-2015), 8 (2016-2017), and 9 (2018-2019). Self-reported cultural engagement (going to museums, art galleries, exhibitions, the theatre, concerts, or the opera) measured in waves 6-8 was used as the exposure variable. Meanwhile self-reported moderate-to-severe pain in wave 9 was used as the outcome variable. Social isolation was considered in waves 6-8, and the possibility of effect modification was captured by assessing each component of the social isolation index: not married or cohabiting with a partner, fewer than monthly contact with children/other immediate family/friends, and not engaging in any organisations, religious groups, or committees. Findings: The estimated pain prevalence was 29.2% (95% confidence interval, 28.1-30.3; reference) after adjusting for time-variant, time-invariant, and loss to follow-up factors. Cultural engagement led to a reduction in pain prevalence to 24.1% for all individuals, representing a decrease of 5.1% (95% confidence interval, 0.6-9.6; P-value, 0.03). In older people who were not married or cohabiting, cultural engagement resulted in a decrease in pain prevalence to 25.8%, a reduction of 3.4% (95% confidence interval, 0.4-6.4; P-value, 0.01). For those with less frequent contact with close family members, the pain prevalence decreased to 25.3%, a reduction of 3.9% (95% confidence interval, 0.2-7.6; P-value, 0.03). Meanwhile, other dimensions of social isolation did not show a significant reduction in pain prevalence. Interpretation: Cultural engagement may help to reduce the risk of pain in socially isolated older adults. Those who were single or living alone and had less frequent contact with immediate family were particularly vulnerable. While cultural engagement might help certain socially isolated older people feel better, its effectiveness varies, highlighting the need for targeted interventions. Funding: The Japan Society for the Promotion of Science (JSPS) KAKENHI Grant Number (22K17648, Ikeda).

Radiographic alveolar bone assessment in correlation with primary implant stability: A systematic review and meta-analysis.

INTRODUCTION: The radiographic examination of alveolar bone using 3D radiographic examination is essential in dental implant treatment planning. Our study aimed to systematically review and quantitatively analyze the correlation between alveolar bone parameters, specifically bone density and cortical bone thickness, assessed using cone beam computed tomography (CBCT) and/or multidetector computed tomography (MDCT); and primary implant stability (PIS) determined using implant stability quotient (ISQ), Periotest® value (PTV), and insertion torque value (ITV). METHODS: This review was registered in the PROSPERO database (registration number CRD42022307245). An electronic literature search was conducted on the PubMed, SCOPUS, and Web of Science databases for papers published until February 2022. The Quality Assessment in Prognostic Studies (QUIPS) tool was used to assess risk of bias. Meta-analyses were conducted to calculate the estimated average correlation coefficient based on a multilevel random-effects model, followed by subgroup analysis. RESULTS: Twenty-six studies were included in this review, consisting of 17 prospective cohort studies, eight retrospective cohort studies, and one nonrandomized controlled trial. A total of 3109 implants placed in 1171 subjects were analyzed. Twenty-three studies were evaluated using meta-analysis. The alveolar bone condition was significantly correlated with ISQ (r = 0.60; p < .001), IT (r = 0.52; p < .001), and PTV (r = -0.42; p < .05). CONCLUSION: Alveolar bone condition is significantly associated with PIS. Low bone density and thin cortical bone can lead to low PIS; therefore, modification of treatment planning and surgical procedures might be needed to avoid poor osseointegration.

Does online communication mitigate the association between a decrease in face-to-face communication and laughter during the COVID-19 pandemic? A cross-sectional study from JACSIS study.

Laughter has a protective effect on human health. The spread of coronavirus disease 2019 (COVID-19) has changed opportunities for face-to-face communication and might decrease opportunities for laughter. This cross-sectional study aimed to investigate whether the decrease in face-to-face communication during the COVID-19 pandemic is associated with a decrease in laughter. Additionally, we investigated whether an increase in online communication mitigates this association. Data from the "Japan COVID-19 and Society Internet Survey (JACSIS)," conducted between August and September 2020, were used. Participants aged 15-79 years were included in this study. The outcome was a decrease in laughter before the onset of the COVID-19 pandemic. The explanatory variables were decreased face-to-face communication with friends and increased online communication (text message, telephone, and video contact). Causal mediation analysis was used to calculate prevalence ratios (PRs) and 95 % confidence intervals (CIs) of the controlled direct effects of increased online communication. Furthermore, the proportions eliminated (PEs) by an increase in online communication were calculated. Among the 25,482 participants, 40.4 % had decreased face-to-face communication and 21.4 % had a decreased frequency of laughter. After adjusting for confounders, a decrease in face-to-face communication was significantly associated with a decrease in laughter (PR = 1.62, 95 %CI = 1.55-1.70). PEs for decrease in laughter were 27.2 % (95 %CI = -2.0 to 56.4) for text-based communication, 36.1 % (95 %CI = 12.3-59.8) for telephone-based communication, and 28.6 % (95 %CI = 0.6-56.6) for video-based communication. Although a decrease in face-to-face communication was associated with a decrease in laughter during the COVID-19 pandemic, online communication, particularly telephone-based communication, mitigated this association.

Oral Self-Care, Pneumococcal Vaccination, and Pneumonia Among Japanese Older People, Assessed With Machine Learning.

BACKGROUND: Pneumonia is a leading cause of death worldwide. It is a particularly serious burden in older people, as they tend to have a weakened immune response. Identifying the role of oral self-care and pneumococcal vaccination in healthy, independent older people can aid pneumonia prevention among them. This study investigated the associations between oral self-care, pneumococcal vaccination, and pneumonia experience among independent older people. METHODS: This cross-sectional study used data from the 2016 Japan Gerontological Evaluation Study. We used machine learning to examine the association between oral self-care and the experience of pneumonia over the previous year, stratified by pneumococcal vaccination. The covariates were sex, age, years of education, equivalent annual income, medical history of stroke, oral health status (choking, dryness, number of teeth), and smoking status. The analysis included 17 217 independent older people aged 65 and over. RESULTS: The prevalence of pneumonia experienced among those who brushed their teeth once or less per day was 4.5% and 5.3% for those with and those without pneumococcal vaccinations, respectively. In the unvaccinated group, the odds ratio of pneumonia experience for those who brushed their teeth once or less a day was 1.57 (95% confidence interval: 1.15-2.14) compared to those who brushed their teeth 3 or more times a day. By contrast, there was no significant association between the frequency of toothbrushing and the experience of pneumonia among people who received pneumococcal vaccination. CONCLUSIONS: Oral care influenced the experience of pneumonia among independent older people who did not receive pneumococcal vaccination.

Development and validation of a rurality index for healthcare research in Japan: a modified Delphi study.

OBJECTIVES: Rural-urban healthcare disparities exist globally. Various countries have used a rurality index for evaluating the disparities. Although Japan has many remote islands and rural areas, no rurality index exists. This study aimed to develop and validate a Rurality Index for Japan (RIJ) for healthcare research. DESIGN: We employed a modified Delphi method to determine the factors of the RIJ and assessed the validity. The study developed an Expert Panel including healthcare professionals and a patient who had expertise in rural healthcare. SETTING: The panel members were recruited from across Japan including remote islands, mountain areas and heavy snow areas. The panel recruited survey participants whom the panel considered to have expertise. PARTICIPANTS: The initial survey recruited 100 people, including rural healthcare providers, local government staff and residents. PRIMARY OUTCOME MEASURES: Factors to include in the RIJ were identified by the Expert Panel and survey participants. We also conducted an exploratory factor analysis on the selected factors to determine the factor structure. Convergent validity was examined by calculating the correlation between the index for physician distribution and the RIJ. Criterion-related validity was assessed by calculating the correlation with average life expectancy. RESULTS: The response rate of the final survey round was 84.8%. From the Delphi surveys, four factors were selected for the RIJ: population density, direct distance to the nearest hospital, remote islands and whether weather influences access to the nearest hospital. We employed the factor loadings as the weight of each factor. The average RIJ of every zip code was 50.5. The correlation coefficient with the index for physician distribution was -0.45 (p<0.001), and the correlation coefficients with the life expectancies of men and women were -0.35 (p<0.001) and -0.12 (p<0.001), respectively. CONCLUSION: This study developed the RIJ using a modified Delphi method. The index showed good validity.

Assessing the impacts of smoking cessation and resumption on back pain risk in later life.

BACKGROUND: This study aimed to assess the impacts of smoking cessation and resumption over 4 years on the risk of back pain at the 6-year follow-up among older adults in England. METHODS: We analysed 6467 men and women aged ≥50 years in the English Longitudinal Study of Aging. Self-reported smoking status, assessed in waves 4 (2008-2009) and 6 (2012-2013), was used as exposure for the study, whereas self-reported back pain of moderate or severe intensity, assessed in wave 7 (2014-2015), was used as the outcome. A targeted minimum loss-based estimator was used with longitudinal modified treatment policies to adjust for baseline and time-varying covariates. RESULTS: Regarding the estimation of the effects of changes in smoking status on the risk of back pain, during the follow-up, individuals who resumed smoking within 4 years had a higher risk of back pain than those who avoided smoking for over 4 years, and the relative risk (RR) (95% confidence interval [CI]) was 1.536 (1.214-1.942). Regarding the estimation of effects of smoking cessation on the risk of back pain, smoking cessation over 4 years was associated with a significantly lower risk of back pain, as indicated by the originally observed data, and the RR (95% CI) was 0.955 (0.912-0.999). CONCLUSIONS: Older adults who avoided smoking for over 4 years had a lower risk of back pain. However, those who resumed smoking within 4 years had a higher risk of back pain. SIGNIFICANCE: Older adults who avoided smoking for over 4 years had a lower risk of back pain. However, those who resumed smoking within 4 years had a higher risk of back pain. Our study data suggest the importance of maintaining smoking cessation to reduce the risk of back pain in the older population.

Education-related inequalities in oral health among older adults: Comparing Singapore and Japan.

OBJECTIVES: Oral health inequalities exist worldwide, and cross-country comparisons can provide valuable insights into country-level characteristics contributing to such inequalities. However, comparative studies in Asian countries are limited. This study examined the magnitude of education-related oral health inequalities in older adults in Singapore and Japan. METHODS: Longitudinal data for older adults, aged ≥65 years, from the Panel on Health and Ageing of Singaporean Elderly (PHASE; 2009, 2011-2012, and 2015) and Japan Gerontological Evaluation Study (JAGES; 2010, 2013, and 2016) were used. Dependent variables were being edentate and having a minimal functional dentition (MFD; i.e. ≥20 teeth). The absolute and relative inequalities were calculated using the slope index of inequality (SII) and relative index of inequality (RII) for educational level [low (<6 years); middle (6-12 years); high (>12 years)] in each country. RESULTS: A total of 1032 PHASE participants and 35 717 JAGES participants were included. At baseline among PHASE participants, 35.9% were edentate and 24.4% had MFD, while among JAGES participants, 8.5% were edentate and 42.4% had MFD. The prevalence of low, middle and high educational levels for PHASE was 76.5%, 18.0% and 5.5%, and for JAGES were 0.9%, 78.1% and 19.7%, respectively. Older adults in Japan had lower education-related inequalities for being edentate [for both SII (-0.53, 95% CI = -0.55 to -0.50) and RII (0.40, 95% CI = 0.33-0.48)] and for not having MFD for both SII (-0.24, 95% CI = -0.27 to -0.20) and RII (0.83, 95% CI = 0.79-0.87) compared to Singapore. CONCLUSIONS: Education-related inequalities for being edentate and not having MFD were higher among older adults in Singapore compared to Japan.

Large Contribution of Oral Status for Death Among Modifiable Risk Factors in Older Adults: The Japan Gerontological Evaluation Study (JAGES) Prospective Cohort Study.

BACKGROUND: Oral diseases are preventable and modifiable, but highly prevalent, and cause worse oral status. Particularly, tooth loss has increased in aging societies. However, studies on population-attributable risks of modifiable risk factors for mortality have neglected oral status. This study aimed to investigate the impact of modifiable risk factors on mortality, including oral status. METHODS: This cohort study used the Japan Gerontological Evaluation Study data, including participants aged ≥65 years. The outcome was death between August 2010 and March 2017. We calculated the hazard ratios (HRs) and population attributable fraction (PAF) of modifiable risk factors (oral status, hypertension, depression, heart disease, diabetes, physical activity, smoking status, and alcohol drinking history) for mortality. RESULTS: Analyses included 24 175 men and 27 888 women (mean age: 73.8 [6.0] and 74.2 [6.1], respectively). In men, after adjusting for covariates, having no teeth showed the highest hazard ratio (HR = 1.67, 95% confidence interval [CI] = 1.51-1.86) among the modifiable risk factors, and the PAF for the number of teeth (18.2%) was the second largest following age. In women, having no teeth had the third largest HR (HR = 1.37, 95% CI = 1.19-1.56) following current and former smoking. The PAF for the number of teeth (8.5%) was the sixth largest, which was larger than that of smoking status (4.8%). CONCLUSIONS: In the older population, the HR and PAF of the number of teeth on mortality were sufficiently large compared with other modifiable risk factors, especially in men. Therefore, maintaining good oral status should be included more in global health policies.

Does remaining teeth and dental prosthesis associate with social isolation? A six-year longitudinal study from the Japan Gerontological Evaluation Study (JAGES).

OBJECTIVES: Social isolation was associated with increased mortality and numerous adverse health outcomes. However, the longitudinal association between oral health and social isolation has not been studied. In this longitudinal prospective cohort study, the association between the number of remaining teeth and dental prosthesis use with social isolation after 6-years follow-up was examined. METHODS: Functionally independent adults aged 65 years or older, who were not socially isolated in 2010, were followed up until 2016 in the Japan Gerontological Evaluation Study. Data from 26 417 participants were analysed after random forest imputation to address missing data. Logistic regression models were used to calculate the odds ratio (OR) for incident social isolation in 2016 after adjusting for age, sex, educational attainment, income, activities of daily living, living area and having depressive symptoms. RESULTS: The mean age of the participants at baseline was 72.3 (SD = 5.0). A total of 1,127 (4.3%) participants were socially isolated at follow-up. Of these, 338 (3.2%) had ≥20 teeth (with or without using dental prosthesis), 171 (3.9%) had 10-19 teeth and used dental prosthesis, 112 (4.2%) had 10-19 teeth and did not use the dental prosthesis, 338 (5.1%) had 0-9 teeth and used dental prosthesis, and 168 (7.6%) had 0-9 teeth and did not use the dental prosthesis. Fully adjusted logistic regression models showed that the OR of incident social isolation was higher for those with fewer teeth; OR = 1.13 (95%CI = 0.96-1.33) for those with 10-19 teeth and OR = 1.36 (95%CI = 1.17-1.58) for those with 0-9 teeth, compared to those with ≥20 teeth. The OR of incident social isolation was lower for those who used a dental prosthesis [OR = 0.90, 95%CI = 0.80-1.02)] compared to those who did not use a dental prosthesis. The interaction between the number of teeth and dental prosthesis use demonstrated that the latter mitigated the incidence of social isolation for participants with tooth loss. Compared to those with ≥20 teeth (with or without prosthesis use), participants with 0-9 teeth that did not use a dental prosthesis were 79% [OR = 1.79, 95%CI = 1.49-2.19] more likely to be socially isolated, whereas participants with 0-9 teeth that used a dental prosthesis were only 23% [OR = 1.23, 95%CI = 1.05-1.45] more likely to be socially isolated. CONCLUSION: Tooth loss was the main predictor for social isolation at follow-up, while no dental prostheses use was an additional risk factor. Dental prosthesis use may reduce the risk of social isolation especially in those with severe tooth loss.

Difference of income inequalities of denture use by co-payment rates: A JAGES cross-sectional study.

OBJECTIVES: Studies suggest that wearing dentures to restore missing teeth can have a positive impact on health status. However, income inequalities in denture wearing exist. The aim of this study was to investigate how differing co-payment rates under the current Japanese Universal Health Insurance Coverage System affect income inequalities in denture non-use among older adults with severe tooth loss. METHODS: This cross-sectional study used data from the 2019 Japan Gerontological Evaluation Study (JAGES). Self-administered questionnaires were mailed to 345 356 independent people who did not receive long-term care insurance benefits and were aged ≥65 years. The dependent variable was denture non-use, and the independent variable was the equivalent annual household income. The Slope Index of Inequality (SII) and Relative Index of Inequality (RII) were used with regression-based approaches to determine both absolute and relative inequalities in denture non-use by co-payment rates. The covariates were sex, age, years of education, number of teeth and comorbidities. RESULTS: Of the 240 889 responses received (response rate =69.9%), we analysed 21 594 participants who fulfilled the inclusion criteria. The mean age was 72.8 years (standard deviation =4.1), and 57.6% were men. For 30 per cent, 20 per cent and 10 per cent co-payment rates, the percentages of people who did not use dentures and had severe tooth loss (≤9 teeth) were 18.3%, 13.3%, and 8.5%, respectively. All analyses confirmed significant inequalities in denture non-use. The lower the co-payment rate, the smaller the inequalities. SIIs for each co-payment rate were as follows: 30 per cent =13.35% (95% confidence interval [CI] = 9.61-17.09); 20 per cent =7.85% (95% CI = 4.88-10.81); and 10 per cent =4.85% (95% CI = 2.55-7.16). Inclusion of interaction term between income and co-payment rate significantly lowered the inequalities by co-payment rate in logistic regression analysis and SII. For RII, although the interaction was not statistically significant, a similar trend was observed. CONCLUSIONS: Income inequalities in denture use existed among older adults with severe tooth loss in Japan, and the inequalities appeared to be greater when the co-payment rate was higher.

Changes in Body Mass Index on the Risk of Back Pain: Estimating the Impacts of Weight Gain and Loss.

BACKGROUND: The relationship between obesity and back pain in older populations is poorly understood. This study aimed to examine (a) the impacts of changes in obesity status on back pain risk and (b) the heterogeneity in the influence of changes in obesity status according to muscle strength. METHODS: We analyzed 6 868 participants in waves 4 (2008-2009), 6 (2012-2013), and 7 (2014-2015) of the English Longitudinal Study of Ageing. The exposure comprised continuous body mass index (BMI) values, whereas the outcome comprised self-reported moderate or severe back pain. The targeted minimum loss-based estimator was used to estimate the impacts of hypothetical changes in BMI in each wave under 10 scenarios encompassing a 5%-25% hypothetical reduction/increase in BMI. We also performed stratified analysis using handgrip strength at the baseline. RESULTS: For the hypothetical reduction scenarios, a 10% (relative risk [RR]; 95% confidence interval [CI] = 0.82 [0.73-0.92], p = .001) reduction in BMI estimated a significantly lower back pain risk compared to the observed data. For the hypothetical increase scenarios, a 5% (RR [95% CI] = 1.11 [1.04-1.19], p = .002) increase in BMI estimated a significantly higher back pain risk. Increased BMI had a higher risk of back pain among those with weak strength when stratified by handgrip strength but not among those with strong strength. CONCLUSION: Our study confirmed that weight gain leads to a greater risk of back pain as well as heterogeneity in the influence of changes in obesity status according to the handgrip strength.

Effects of the different periods and magnitude of COVID-19 infection spread on cancer operations: Interrupted time series analysis of medical claims data.

BACKGROUND: No clear evidence exists regarding the effects of the different periods and magnitude of spread of the COVID-19 infection on cancer treatments. This study investigated the effects of the different periods and magnitude of COVID-19 infection spread on in-hospital cancer operations. METHODS: Medical claims data from 17 hospitals where in-hospital operations for patients with malignant neoplasms were performed between 1 April 2017 and 31 March 2021 in Yamagata were extracted and analyzed. The critical time points as exposure used to evaluate the impact of different COVID-19 infection spread periods on cancer operations were (1) April 2020 (emergency declaration introduced by the government) and (2) December 2020 (the second wave). From April to November 2020 and December 2020 to March 21, the number of confirmed COVID-19 cases was 130 and 840, respectively. The 17 hospitals were classified into intervention or control groups based on whether in-hospital treatments for patients with COVID-19 were provided. RESULTS: The interrupted time series analysis reported that the difference in the trend of pre-COVID-19 and postsecond wave (March 2020 to December 2020) periods was statistically significant between groups, with 50.67 fewer operations (95% confidence interval [CI] = 12.19-89.15) performed per month in the intervention group compared with the control group. Moreover, the immediate change in the number of operations in April 2020 (beginning of the first wave) was statistically significant between groups, with 80.14 operations (95% CI = 39.62-120.67) less immediately after the first wave in the intervention group compared with the control group. CONCLUSION: Our findings suggest that a statement of emergency by the government and the COVID-19 infection spread are both associated with the number of cancer operations performed in the Yamagata prefecture during the COVID-19 pandemic.

An Interpretable Machine Learning Approach to Predict Fall Risk Among Community-Dwelling Older Adults: a Three-Year Longitudinal Study.

BACKGROUND: Adverse health effects resulting from falls are a major public health concern. Although studies have identified risk factors for falls, none have examined long-term prediction of fall risk. Furthermore, recent evidence suggests that there are additional risk factors, such as psychosocial factors. OBJECTIVE: In this 3-year longitudinal study, we evaluated a predictive model for risk of fall among community-dwelling older adults using machine learning methods. DESIGN: A 3-year follow-up prospective longitudinal study (from 2010 to 2013). SETTING: Twenty-four municipalities in nine of the 47 prefectures (provinces) of Japan. PARTICIPANTS: Community-dwelling individuals aged ≥65 years who were functionally independent at baseline (n = 61,883). METHODS: The baseline survey was conducted from August 2010 to January 2012, and the follow-up survey was conducted from October to December 2013. Both surveys were conducted involving self-reported questionnaires. The measured outcome at the follow-up survey was self-reported multiple falls during the previous year. The 142 variables included in the baseline survey were regarded as candidate predictors. The random-forest-based Boruta algorithm was used to select predictors, and the eXtreme Gradient Boosting algorithm with 10 repetitions of nested k-fold cross-validation was used for modeling and model evaluation. Furthermore, we used shapley additive explanations to gain insight into the behavior of the prediction model. KEY RESULTS: Fourteen out of 142 candidate features were selected as predictors. Among these predictors, experience of falling as of the baseline survey was the most important feature, followed by self-rated health and age. Moreover, sense of coherence was newly identified as a risk factor for falls. CONCLUSIONS: This study suggests that machine learning tools can be adapted to explore new associative factors, make accurate predictions, and provide actionable insights for fall prevention strategies.

Longitudinal Association Between Oral Status and Cognitive Decline Using Fixed-effects Analysis.

BACKGROUND: Although the feasibility of randomized trials for investigating the long-term association between oral health and cognitive decline is low, deriving causal inferences from observational data is challenging. We aimed to investigate the association between poor oral status and subjective cognitive complaints (SCC) using fixed-effects model to eliminate the confounding effect of unobserved time-invariant factors. METHODS: We used data from Japan Gerontological Evaluation Study (JAGES) which was conducted in 2010, 2013, and 2016. ß regression coefficients and 95% confidence intervals [CIs] were calculated using fixed-effects models to determine the effect of deteriorating oral status on developing SCC. Onset of SCC was evaluated using the Kihon Checklist-Cognitive function score. Four oral status variables were used: awareness of swallowing difficulty, decline in masticatory function, dry mouth, and number of teeth. RESULTS: We included 13,594 participants (55.8% women) without SCC at baseline. The mean age was 72.4 (standard deviation [SD], 5.1) years for men and 72.4 (SD, 4.9) years for women. Within the 6-year follow-up, 26.6% of men and 24.9% of women developed SCC. The probability of developing SCC was significantly higher when participants acquired swallowing difficulty (ß = 0.088; 95% CI, 0.065-0.111 for men and ß = 0.077; 95% CI, 0.057-0.097 for women), decline in masticatory function (ß = 0.039; 95% CI, 0.021-0.057 for men and ß = 0.030; 95% CI, 0.013-0.046 for women), dry mouth (ß = 0.026; 95% CI, 0.005-0.048 for men and ß = 0.064; 95% CI, 0.045-0.083 for women), and tooth loss (ß = 0.043; 95% CI, 0.001-0.085 for men and ß = 0.058; 95% CI, 0.015-0.102 for women). CONCLUSION: The findings suggest that good oral health needs to be maintained to prevent the development of SCC, which increases the risk for future dementia.

Maintaining Moderate or Vigorous Exercise Reduces the Risk of Low Back Pain at 4 Years of Follow-Up: Evidence From the English Longitudinal Study of Ageing.

Few studies have examined whether maintaining moderate or vigorous physical activity (PA) reduces the risk of low back pain in older people. This study aimed to examine the magnitude of the associations of changes in PA on the risk of low back pain at 4 years of follow-up. We analyzed 4,882 participants in the English Longitudinal Study of Ageing who were initially free from low back pain (mean age, 65.6 ± 8.9 years at baseline). Self-reported PA, which was assessed at wave 6 (2012-2013) and wave 7 (2014-2015), was used as the exposure. The PA of the respondents was categorized into "no PA at all," "up to moderate PA," and "up to vigorous PA" groups. Self-reported moderate/severe low back pain assessed at 4 years of follow-up (2016-2017) was used as the outcome. Maintaining moderate (relative risk [RR], 0.59; 95% confidence interval [CI], 0.36-0.99) or vigorous (RR, 0.46; 95% CI, 0.27-0.77) PA at least 1-3 times a month was negatively associated with prevalence of low back pain compared with no PA at all. Interventions for maintaining either moderate or vigorous PA might be beneficial in preventing the incidence of low back pain in the older population. PERSPECTIVE: This study examined the magnitude of the association between changes in physical activity over time and the risk of low back pain. The findings suggest that encouraging people to maintain at least moderate physical activity over 2 years is useful for reducing the risk of low back pain at 4 years of follow-up.

Importance of socioeconomic factors in predicting tooth loss among older adults in Japan: Evidence from a machine learning analysis.

Prevalence of tooth loss has increased due to population aging. Tooth loss negatively affects the overall physical and social well-being of older adults. Understanding the role of socio-demographic and other predictors associated with tooth loss that are measured in non-clinical settings can be useful in community-level prevention. We used high-dimensional epidemiological data to investigate important factors in predicting tooth loss among older adults over a 6-year period of follow-up. Data was from participants of 2010 and 2016 waves of the Japan Gerontological Evaluation Study (JAGES). A total of 19,407 community-dwelling functionally independent older adults aged 65 and older were included in the analysis. Tooth loss was measured as moving from a higher number of teeth category at the baseline to a lower number of teeth category at the follow-up. Out of 119 potential predictors, age, sex, number of teeth, denture use, chewing difficulty, household income, employment, education, smoking, fruit and vegetable consumption, community participation, time since last health check-up, having a hobby, and feeling worthless were selected using Boruta algorithm. Within the 6-year follow-up, 3013 individuals (15.5%) reported incidence of tooth loss. People who experienced tooth loss were older (72.9 ± 5.2 vs 71.8 ± 4.7), and predominantly men (18.3% vs 13.1%). Extreme gradient boosting (XGBoost) machine learning prediction model had a mean accuracy of 90.5% (±0.9%). A visual analysis of machine learning predictions revealed that the prediction of tooth loss was mainly driven by demographic (older age), baseline oral health (having 10-19 teeth, wearing dentures), and socioeconomic (lower household income, manual occupations) variables. Predictors related to wide a range of determinants contribute towards tooth loss among older adults. In addition to oral health related and demographic factors, socioeconomic factors were important in predicting future tooth loss. Understanding the behaviour of these predictors can thus be useful in developing prevention strategies for tooth loss among older adults.

Influence of bone condition on implant placement accuracy with computer-guided surgery.

BACKGROUND: The impact of the jaw bone condition, such as bone quantity and quality in the implant placement site, affecting the accuracy of implant placement with computer-guided surgery (CGS) remains unclear. Therefore, this study aimed to evaluate the influence of bone condition, i.e., bone density, bone width, and cortical bone thickness at the crestal bone on the accuracy of implant placement with CGS. METHODS: A total of 47 tissue-level implants from 25 patients placed in the posterior mandibular area were studied. Implant placement position was planned on the simulation software, Simplant® Pro 16, by superimposing preoperative computed tomography images with stereolithography data of diagnostic wax-up on the dental cast. Implant placement surgery was performed using the surgical guide plate to reflect the planned implant position. The post-surgical dental cast was scanned to determine the position of the placed implant. Linear and vertical deviations between planned and placed implants were calculated. Deviations at both platform and apical of the implant were measured in the bucco-lingual and mesio-distal directions. Intra- and inter-observer variabilities were calculated to ensure measurement reliability. Multiple linear regression analysis was employed to investigate the effect of the bone condition, such as density, width, and cortical bone thickness at the implant site area, on the accuracy of implant placement (α = 0.05). RESULT: Intra- and inter-observer variabilities of these measurements showed excellent agreement (intra class correlation coefficient ± 0.90). Bone condition significantly influenced the accuracy of implant placement using CGS (p < 0.05). Both bone density and width were found to be significant predictors. CONCLUSIONS: Low bone density and/or narrow bucco-lingual width near the alveolar bone crest in the implant placement site might be a risk factor influencing the accuracy of implant placement with CGS.

Inequalities in Caries Experience Among Mongolian Children.

Although inequalities in dental caries have been well-reported, there is only one Mongolian study on the association between socioeconomic status (SES) and caries experience, which was published ten years ago. This study aimed to determine the dental health status of Mongolian children living in urban and suburban areas of Ulaanbaatar city and examine its association with income and parental educational attainment. An oral examination was conducted by dentists and caries were measured as deft/DMFT indices. A questionnaire including demographic characteristics and socioeconomic status was completed by their parents or caregiver. Parental educational attainment and household income were used as the measures of SES. The relative index of inequality (RII) and slope index of inequality (SII) were employed to examine the association between SES on deft and DMFT after adjusting for covariates. Dental caries prevalence (those with deft/DMFT > 0) was 89.3% among the total number of participants. The mean deft/DMFT values for age groups 1-6, 7-12, and 13-18 were 5.83 (SD = 4.37, deft), 5.77 (SD = 3.31, deft/DMFT), and 3.59 (SD = 2.69, DMFT), respectively. Rather than residence area and parental educational attainment, significant caries experience inequality was observed in relation to income (RII 0.65 95%, CI 0.52 to 0.82, SII -2.30, 95% CI -4.16 to -0.45). A prevention strategy for lower socioeconomic groups and building integrated oral health surveillance to monitor epidemiological trends for further evaluation of its progress is necessary.