Does Tobacco Smoking Increase Social Isolation? A Mendelian Randomization Study.

In this study, we aimed to investigate the causal effect of smoking on social isolation among older adults in England. Data from older adults of European ancestry who participated in 1 or more waves of the English Longitudinal Study of Ageing, from wave 1 (2002/2003) to wave 9 (2018/2019), were analyzed (n = 43,687 observations from 7,008 individuals; mean age = 68.50 years). The effect of current smoking on social isolation (ranging from 0 to 5) was estimated by 2-stage least squares regression using a polygenic score (PGS) for smoking cessation as the instrument. A low PGS for smoking cessation predicted current smoking (per 1-standard-deviation lower PGS, coefficient = 0.023, 95% confidence interval (CI): 0.015, 0.030; F = 36.420). The second-stage regression showed that current smoking increased social isolation by 1.205 points (95% CI: 0.308, 2.101). The association was larger for persons with higher socioeconomic backgrounds: 2.501 (95% CI: -0.024, 5.026) and 0.696 (95% CI: -0.294, 1.686) for those with higher and lower educational levels, respectively. This study showed that current smoking instrumented by a PGS for smoking cessation was associated with social isolation. Assuming that the PGS served as a valid instrument in this study, the findings support an effect of smoking on social isolation.

Determining the most appropriate socioeconomic status indicator for describing inequalities in dental visits by Japanese older people.

OBJECTIVES: This study examined the association between various socioeconomic status (SES) indicators and dental visits among older Japanese. BACKGROUND: When examining health inequalities, an adequate indicator of SES should be applied. In older adults, wealth and pensions are considered more appropriate indicators of SES than education and income, but few studies have examined. METHODS: This cross-sectional study used data from 12 391 individuals aged 65 years or older from the 2016 Japan Gerontological Evaluation Study (JAGES). The Slope Index of Inequality (SII) and the Relative Index of Inequality (RII) were applied to examine the association of education, income, wealth and pensions with dental visits for treatment and check-up adjusting for covariates. RESULTS: The mean age of the participants was 74.0 ± 6.2 years. In the previous year, 56.3% of participants had visited a dentist for a check-up, and 65.9% had visited for treatment. Inequalities in dental treatment visits were observed for wealth, pensions and income rather than education. Income was not significantly associated with check-up visits. Wealth showed the largest association with dental visits for treatment [(SII 0.09, 95% CI 0.06 to 0.13), (RII 1.14, 95% CI 1.09 to 1.21)] and check-up [(SII 0.08, 95% CI 0.05 to 0.12), (RII 1.16, 95% CI 1.09 to 1.23)]. CONCLUSION: When measuring inequalities in access to dental care among the older population, wealth and pensions could be important indicators of SES.

Duration of Education and Back Pain: Lessons From English Schooling Reforms.

This study aimed to examine the associations of increases in the duration of education with back pain using the exogenous variation generated by the English schooling reforms of 1947 and 1972. We analyzed cross-sectional data derived from 9 waves (waves 1-9; 2002-2019) of the English Longitudinal Study of Ageing. An instrumental variables regression using 2-stage least squares with the 2-way cluster-robust standard error was used. The mean severity of back pain, measured using the Numerical Rating Scale, was used as the outcome. A total of 22,868 observations from 5,070 participants were included (the 1947 reform = 16,565 observations from 3,231 participants, mean age = 74.5 years; the 1972 reform = 6,303 observations from 1,839 participants, mean age = 59.3 years). The schooling reforms significantly extended years of school attendance by a mean of 0.57 years for the 1942 reform cohort and 0.66 years for 1972 reform cohort. For participants born within 5 years of the pivotal cohorts, an additional year of education decreased the severity of back pain by 0.78 points (95% confidence interval: 0.65, 0.92) for the 1972 reform cohort. Our finding underscores the importance of the length of education in the reduction of back pain in middle-aged individuals.

Stepwise Tobacco Price Increase and Smoking Behavioral Changes in Japan: The Japan "Society and New Tobacco" Internet Survey 2017-2021 Longitudinal Study.

INTRODUCTION: Tobacco price increase is an effective measure to reduce tobacco smoking. In Japan, the price of combustible cigarettes increased in 2018 and 2020, and that of heated tobacco products increased every year from 2018 to 2020 by tobacco excise taxation. Also, the general consumption tax increase in 2019 slightly raised the retail prices of tobacco products. We investigated the impact of this stepwise tobacco price increase on combustible cigarette smoking status among Japanese adults. AIMS AND METHODS: Five waves of annual longitudinal data (2017-2021) from The Japan "Society and New Tobacco" Internet Survey (JASTIS) (31 930 observations of 11 896 individuals) were analyzed. Multivariable logistic regression with a generalized estimating equation was fitted, adjusting for the prefecture of residence, age, sex, socioeconomic status, health status, alcohol drinking, former smoker's duration of smoking cessation, and the current smoker's number of cigarettes smoked per day. RESULTS: The 2018 price increase was associated with a reduction in relapse (adjusted odds ratio [aOR] 0.54, 95% confidence interval [CI] 0.42-0.68) and an increment in cessation (aOR 1.20, 95% CI 1.02-1.42). The price increase in 2019 was not associated with relapse (aOR 0.84, 95% CI 0.63-1.10) or cessation (aOR 0.95, 95% CI 0.80-1.13). The 2020 price increase was associated with a reduction in relapse (aOR 0.59, 95% CI 0.42-0.81) and an increment in cessation (aOR 1.45, 95% CI-1.21, 1.73). CONCLUSION: The price increase caused by tobacco excise taxation was associated with a reduction in combustible cigarette smoking. IMPLICATIONS: Japan introduced a policy of stepwise increase in tobacco excise taxation in 2018. We analyzed five-wave longitudinal data to investigate the impact of the policy. Tobacco price increases in 2018 and 2020 were associated with a reduction in combustible cigarette smoking. Tobacco price increases in 2019 by general consumption tax were not associated with a change in combustible cigarette smoking.

Being Left Alone at Home and Dental Caries of Children Aged 6-7 Years.

BACKGROUND: Leaving children alone at home is considered child neglect in some countries but is not prohibited in Japan. We investigated the association between being left alone at home and dental caries of children aged 6-7 years in Japan. METHODS: The data on first graders in all 69 public elementary schools in Adachi, Tokyo, obtained from repeated cross-sectional surveys in 2015, 2017, and 2019 were analyzed. Caregivers answered the questionnaire, and the data were linked to the information on children's dental caries evaluated in school dental health checkups (N = 12,029). Poisson regression analysis with propensity score matching (PSM) was applied to account for confounders. RESULTS: Leaving children alone at home for ≥1 hour during the weekdays was reported by 46.4% of the caregivers, which did not vary across years. The PSM analysis showed that, compared with children never being left alone at home, children being left alone at home for ≥1 time per week had more dental caries (mean ratio [MR] 1.11; 95% confidence interval (CI), 1.02-1.21; P = 0.016), while <1 time per week was not associated (MR 0.97; 95% CI, 0.92-1.03; P = 0.345). The difference between those being left alone at home for <1 time per week and those being left alone for ≥1 time per week was not significant after applying Bonferroni correction (MR 1.12; 95% CI, 1.00-1.26; P = 0.041). CONCLUSION: Leaving children alone at home for ≥1 hour every week might be a risk factor for dental caries of children aged 6-7 years.

Time-varying exposure analysis of the relationship between sustained natural dentition and cognitive decline.

AIM: Tooth loss and cognitive decline progress over time and influence each other. This study estimated the impact of sustaining natural dentition on cognitive function in U.S. adults, accounting for the fact that dental and cognitive statuses change over time. MATERIALS AND METHODS: Data from adults aged ≥51 years who participated in five waves of the Health and Retirement Study from 2004 to 2016 (n = 10,953) were analysed. The impact of retaining some natural teeth from 2006 to 2012 on cognitive function score (0-27) and cognitive impairment (defined as having a cognitive function score of <12) in 2016 was evaluated using the doubly robust targeted maximum likelihood estimation method by considering both time-invariant and time-varying confounders, including cognitive function at baseline and during follow-up. RESULTS: Respondents with some natural teeth between 2006 and 2012 had a 0.40 point (95% confidence interval [CI]: 0.10-0.71) higher cognitive function score and 3.27 percentage point (95% CI: 0.11-6.66) lower cognitive impairment prevalence in 2016 than those with complete tooth loss. CONCLUSIONS: Considering past cognitive function assessed at multiple time points, sustained natural dentition was associated with better cognitive function.

Phenylephrine-Induced Contraction in Guinea Pig Thoracic Aorta Is Triggered by Stimulation of α1L-Adrenoceptors Functionally Coupled with Store-Operated Ca2+ Channels and Voltage-Dependent Ca2+ Channels.

We examined whether the α1L-adrenoceptor (AR), which shows low affinity (pA2 < 9) for prazosin (an α1-AR antagonist) and high affinity (pA2 ≈ 10) for tamsulosin/silodosin (α1A-AR antagonists), is involved in phenylephrine-induced contractions in the guinea pig (GP) thoracic aorta (TA). Intracellular signaling induced by α1L-AR activation was also examined by focusing on Ca2+ influx pathways. Tension changes of endothelium-denuded TAs were isometrically recorded and mRNA encoding α-ARs/Ca2+ channels and their related molecules were measured using RT-quantitative PCR. Phenylephrine-induced contractions were competitively inhibited by prazosin/tamsulosin, and their pA2 value were calculated to be 8.53/9.74, respectively. These contractions were also inhibited by silodosin concentration-dependently. However, the inhibition was not competitive fashion with the apparent pA2 value being 9.48. In contrast, phenylephrine-induced contractions were not substantially suppressed by L-765314 (an α1B-AR antagonist), BMY 7378 (an α1D-AR antagonist), yohimbine, and idazoxan (α2-AR antagonists). Phenylephrine-induced contractions were markedly inhibited by YM-254890 (a Gq protein inhibitor) or removal of extracellular Ca2+, and partially inhibited by verapamil (a voltage-dependent Ca2+ channel (VDCC) inhibitor). The residual contractions in the presence of verapamil were slightly inhibited by LOE 908 (a receptor-operated Ca2+ channel (ROCC) inhibitor) and strongly inhibited by SKF-96365 (a store-operated Ca2+ channel (SOCC) and ROCC inhibitor). Among the mRNA encoding α-ARs/SOCC-related molecules, α1A-AR (Adra1a)/Orai3, Orai1, and Stim2 were abundant in this tissue. In conclusion, phenylephrine-induced contractions in the GP TA can be triggered by stimulation of Gq protein-coupled α1L-AR, followed by activation of SOCCs and VDCCs.

Peritoneal closure and the processus vaginalis transection method to prevent inguinal hernia after robot-assisted radical prostatectomy.

OBJECTIVES: Postoperative inguinal hernia (IH) is one of the most common complications of radical prostatectomy (RP) including robot-assisted RP (RARP). However, a procedure to prevent IH after RARP has not been established. We investigated the impact of processus vaginalis transection (PVT) and PVT with peritoneal closure on IH after RARP. METHODS: A retrospective analysis was performed on data from patients who underwent RARP at two tertiary hospitals in Japan, where PVT with subsequent peritoneal closure was introduced after 2014. The incidence of IH for 2 years after RARP was compared among 79 patients without PVT or peritoneal closure, 232 patients with only PVT, and 325 patients with PVT and peritoneal closure. Multivariable Cox proportional hazard models that adjusted for hospital, age, history of abdominal operation, body mass index, operation time, and prostate weight were used. RESULTS: Postoperative IH was observed in seven (8.9%) patients without PVT or peritoneal closure, 34 (15%) patients with only PVT, and nine (2.8%) patients with PVT and peritoneal closure. Compared with patients without PVT or peritoneal closure, the incidence of IH was not different in patients with only PVT (hazard ratio [HR] 0.89, 95% confidence interval [CI] 0.34, 2.38) and significantly lower in patients with PVT and peritoneal closure (HR 0.22, 95% CI 0.07, 0.70). CONCLUSION: PVT with peritoneal closure may reduce the risk of postoperative IH after RARP. Future randomized controlled trials are required to confirm these findings.

A cross-sectional study evaluating patients' preferences for Salter innominate osteotomy.

BACKGROUND: Residual acetabular dysplasia in children after reduction of hip dislocation is often treated using Salter innominate osteotomy to prevent future osteoarthritis. Preventive surgery for asymptomatic patients, which could result in overtreatment, should be carefully applied with consideration of patients' opinions. In this study, we aimed to describe opinions on Salter innominate osteotomy as preventive surgery for children among adult patients who had undergone periacetabular osteotomy for hip pain due to hip dysplasia. METHODS: A mail-in questionnaire survey was conducted with 77 patients who underwent periacetabular osteotomy. Participants responded whether they would recommend Salter innominate osteotomy as preventive surgery for children and the reason for their opinion. We also performed a patient-based evaluation using the Japanese Orthopaedic Association Hip-Disease Evaluation Questionnaire and assessed clinical outcome measures with the Japanese Orthopedic Association score. Their recommendations and reasons were evaluated, and associations between their opinions and demographic and clinical characteristics were analyzed. RESULTS: Forty-three patients (56%) responded to the questionnaire. Of these, 10 (23%) patients recommended undergoing Salter innominate osteotomy, 28 (65%) patients did not, and 5 (12%) patients responded they were undecided. No significant association was observed between their opinions and demographic/clinical characteristics evaluated in the survey. The most frequent reason for why they do not recommend Salter innominate osteotomy was related to uncertainty about future hip pain. CONCLUSIONS: In total, 65% of the study participants did not recommend Salter innominate osteotomy for children with risk of dysplasia in the future. Participants' preferences regarding preventive surgery were not influenced by demographic and clinical characteristics.

Differences in Brain Volume by Tooth Loss and Cognitive Function in Older Japanese Adults.

BACKGROUND: We investigated the association between tooth loss and structural brain volume and its mediating effect on the association between tooth loss and cognitive function in older Japanese. METHODS: A cross-sectional study was conducted by using the data of 494 randomly sampled community-dwelling individuals aged 65-84 years living in Tokamachi City, Japan. Total brain volume (TBV), gray matter volume (GMV), white matter volume (WMV), and hippocampal volume (HV) were measured with magnetic resonance imaging. The association of self-reported number of teeth (≥20, 1-19, and 0) with cognitive function assessed with the Japanese version of the Quick Mild Cognitive Impairment screen and structural brain volume was examined. Causal mediation analysis was performed to evaluate the mediating effect of structural brain volume. Age, sex, socioeconomic status, health behavior, comorbid conditions, and total intracranial volume were adjusted. RESULTS: Respondents with no teeth showed lower cognitive function (coefficient = -4.01; 95% confidence interval [CI]: -7.19, -0.82), lower TBV (coefficient = -10.34; 95% CI: -22.84, 2.17), and lower GMV (coefficient = -6.92; 95% CI: -14.84, 0.99) than those with ≥20 teeth (P for trends were 0.003, 0.035, and 0.047, respectively). The number of teeth was not significantly associated with WMV or HV. GMV showed a significant mediating effect on the association between the number of teeth and cognitive function (coefficient = -0.38; 95% CI: -1.14, -0.002, corresponding to 9.0% of the total effect), whereas TBV did not. CONCLUSIONS: GMV was suggested to mediate the relationship between tooth loss and lower cognitive function.

Mucosal healing of small intestinal stricture is associated with improved prognosis post-dilation in Crohn's disease.

BACKGROUND: Small intestinal stricture is a major cause for surgery in Crohn's disease (CD). Endoscopic balloon dilation (EBD) is performed for small intestinal strictures to avoid surgery, often repeatedly. However, factors that are associated with prognosis after EBD of small intestinal strictures remain poorly investigated. Mucosal healing is the therapeutic target in CD. We aimed to investigate the impact of mucosal healing defined by the presence of ulcers at the small intestinal stricture site on the prognosis of EBD in CD patients. METHODS: We retrospectively included patients with CD who underwent initial EBD for endoscopically impassable small intestinal strictures from January 2012 to March 2020 at a single center. The association between presence of ulcer at the stricture site and surgery after EBD was examined by Cox proportional hazards model. RESULTS: Of the 98 patients included, 63 (64.3%) had ulcer at the stricture site. 20 (31.7%) of these patients underwent surgery for the stricture in due course, whereas 4 (11.4%) of the patients without ulcer of the stricture underwent surgery. In multivariate analysis, patients with ulcer of the stricture had a significantly higher risk for surgery than those without ulcer (hazard ratio 4.84; 95% confidence interval 1.58-14.79). CONCLUSION: Mucosal healing at the stricture site indicated a favorable prognosis after EBD for small intestinal strictures in CD.

Association Between Procrastination in Childhood and the Number of Remaining Teeth in Japanese Older Adults.

BACKGROUND: Procrastination is associated with stress and unhealthy behaviors. The oral condition reflects the long-term history of an individual's stress exposure and oral health behaviors; however, empirical studies on the association of procrastination in childhood with remaining teeth in older age are limited. We investigated the association of procrastination in childhood with the number of remaining teeth among community-dwelling older Japanese adults. METHODS: In total, 1,616 community-dwelling senior residents of Wakuya City (Miyagi Prefecture, Japan) who were enrolled in the National Health Plan & the Medical Care System for the Elderly completed a self-administered questionnaire on the number of teeth. Procrastination was measured using a single binary question about timing of holiday homework completion in childhood. The number of remaining teeth was assessed via a questionnaire with response options of ≥20, 10-19, 1-9, and 0 teeth. Ordered logistic regression models with potential confounders (sex, age, maternal education, childhood socioeconomic status [SES], childhood maltreatment, conscientiousness trait) and mediators (adulthood SES, smoking history, alcohol use history) were estimated. RESULTS: Forty-six percent of participants reported a higher tendency to procrastinate in childhood. The proportions of participants with ≥20, 10-19, 1-9, and 0 teeth were 39.6%, 22.7%, 24.0%, and 13.7%, respectively. After adjusting for all covariates, a higher tendency to procrastinate in childhood was significantly associated with having fewer remaining teeth (odds ratio 1.28; 95% confidence interval, 1.05-1.57). CONCLUSION: A higher tendency to procrastinate in childhood was associated with having fewer remaining teeth in later life.

Heated tobacco product use and combustible cigarette smoking relapse/initiation among former/never smokers in Japan: the JASTIS 2019 study with 1-year follow-up.

BACKGROUND: Use of heated tobacco products (HTPs), which were first launched in Japan, has been rapidly spreading worldwide. The present study aimed to investigate whether HTP use was associated with combustible cigarette smoking relapse/initiation among former/never combustible cigarette smokers. METHODS: A prospective cohort study was conducted by analysing two waves of data from the Japan 'Society and New Tobacco' Internet Survey. Among the 7766 never/former combustible cigarette smokers who answered the baseline survey in 2019, 5947 (follow-up rate: 76.6%) responded to the follow-up survey in 2020 (age range 18-73 years old; 50.5% men). The association between HTP use and combustible smoking after 1 year was investigated by multivariable logistic regression analysis adjusting for potential confounders. RESULTS: Of the respondents, 308 (5.2%) used HTPs at baseline. One year later, 97 (1.7%) non-HTP users and 39 (12.7%) HTP users were smoking combustible cigarettes. Among former smokers who had quit for 1 year or more and among never smokers, HTP use was significantly associated with combustible cigarette smoking 1 year later (OR=2.80, 95% CI 1.42 to 5.52 and OR=9.95, 95% CI 3.39 to 29.16, respectively), while the association was not significant among former smokers who recently quit. CONCLUSION: HTP use was associated with relapse/initiation of combustible cigarette smoking after 1 year. The risks of HTP use, including subsequent combustible smoking, should be carefully monitored.

Impacts of the COVID-19 Pandemic Exposure on Child Dental Caries: Difference-in-Differences Analysis.

The impact of the coronavirus disease 2019 (COVID-19) pandemic on dental caries is unknown. We investigated the effect of the pandemic on child dental caries in Japan by comparing the increase in dental caries from fourth to sixth grade between two cohorts, COVID-19 exposed cohort and COVID-19 unexposed cohort, using difference-in-differences analysis. Longitudinal data that followed elementary school children in Adachi City, Tokyo, were analyzed. The analysis consisted of two cohorts: those who were in fourth grade in 2016 and sixth grade in 2018 (COVID-19 unexposed cohort, N = 399) and those who were in fourth grade in 2018 and sixth grade in 2020 (COVID-19 exposed cohort, N = 3,082). Children's dental caries were examined by school dentists. A difference-in-differences analysis, adjusting for time-variant variables, i.e., household socioeconomic status, children's oral health behavior, and caregivers' psychological distress, was performed. In fourth grade, the number of Decayed, Missing, and Filled permanent Teeth (DMFT) was not different between the COVID-19 unexposed and exposed cohorts (mean = 0.241 and 0.242, respectively). In sixth grade, DMFT increased by 0.067 in the COVID-19 unexposed cohort and 0.180 in the COVID-19 exposed cohort. The interaction term of grade and cohorts for caries by difference-in-differences analysis showed that dental caries among the COVID-19 exposed cohort showed a significant increase in the number of dental caries by 0.116 (95% confidence interval 0.015, 0.216) compared to the COVID-19 unexposed cohort. Child dental caries slightly increased after the pandemic. Studies with longer follow-ups are needed to evaluate the impact of the pandemic on child dental caries.

Association between periodontal inflammation and serum lipid profile in a healthy population: A cross-sectional study.

AIMS: The impact of periodontal inflammation on lipid metabolism is controversial. This study aimed to investigate the association between full-mouth periodontal inflammation and serum lipid levels. MATERIALS AND METHODS: In this cross-sectional study, we performed periodontal and bacteriological examinations during medical checkup on 131 subjects. The association between the periodontal inflamed surface area (PISA) and the lipid markers was analyzed by multiple linear regression, adjusting for age, sex, smoking, and body mass index. RESULTS: Overall, 118 medically healthy participants were analyzed. The proportions of none, mild, moderate, and severe periodontitis were 37.3%, 32.2%, 25.4%, and 5.1%, respectively. Multivariate analysis showed that high-density lipoprotein cholesterol was significantly higher in participants with the lowest tertile of PISA values (PISA low, coefficient: 7.94; 95% confidence interval [CI]: 1.63, 14.26, p = .01) compared to those in other tertiles (PISA high). Low-density/high-density lipoprotein cholesterol and total/high-density lipoprotein cholesterol ratios were significantly lower in the PISA-low group than the PISA-high group (coefficient: -0.26 and -0.30; 95% CI: -0.50, -0.02, and -0.59, -0.0002; p = .04 and .0498). Serum high-sensitivity C-reactive protein level, but not serum Porphyromonas gingivalis antibody titer, partly explained the association between PISA and high-density lipoprotein cholesterol. A significant interaction between female sex and PISA values toward high-density lipoprotein cholesterol level was detected. CONCLUSION: Periodontal inflammation was inversely associated with higher high-density lipoprotein cholesterol, especially in females. Elevated serum C-reactive protein partly explained this association.

Association between circulating tumor necrosis factor receptors and oral bacterium in patients receiving hemodialysis: a cross-sectional study.

BACKGROUND: High levels of tumor necrosis factor (TNF) receptors (TNFRs; TNFR1 and TNFR2), markers of inflammation, have been reported as significant predictors of mortality in hemodialysis patients. Porphyromonas gingivalis is a major pathogenic bacterium involved in periodontitis, which induces systemic inflammation. We investigated the association between the abundance of P. gingivalis in saliva and serum TNFR levels in hemodialysis patients. METHODS: A cross-sectional study was conducted on 121 hemodialysis patients visiting a clinic in the Tokyo metropolitan area. Medical interviews and examinations, comprehensive dental examinations, bacterial examinations for P. gingivalis in saliva, and measurements of circulating TNFR levels were conducted. Multiple linear regression analysis was performed to evaluate the association between the number of P. gingivalis and circulating TNFR levels. RESULTS: TNFR1 and TNFR2 were positively correlated with high-sensitivity C-reactive protein (hsCRP). Severe periodontitis was significantly associated with the number of P. gingivalis in saliva but not serum TNFR levels. The number of P. gingivalis was significantly associated with both TNFR1 and TNFR2 levels in sera after adjusting for age, sex, body mass index, smoking status, history of diabetes, prior cardiovascular disease events, serum levels of hsCRP and albumin, and severity of periodontitis [for TNFR1: coefficient 0.76, 95% confidence interval (CI) 0.14-1.37, p = 0.02; for TNFR2: coefficient 0.95, 95% CI 0.09-1.80, p = 0.03]. CONCLUSION: Circulating TNFR levels are associated with the number of P. gingivalis in saliva after adjusting for relevant clinical factors.

Does oral dryness influence pressure pain sensitivity in the oral mucosa of removable denture wearers?

OBJECTIVE: This study aimed to determine if oral dryness is associated with oral pain sensitivity in removable denture wearers. MATERIALS AND METHODS: The pressure pain threshold (PPT) in the mucosa at the midline between the central incisors in the maxilla and mandible was evaluated in 333 removable denture wearers (mean age 71.2 years, male 33.3%). The frequency of oral dryness and severity of anxiety were evaluated using self-reported questionnaires. Multilevel analyses considering the correlated data structure (jaws nested within individual) adjusted for age, sex, number of missing teeth, anxiety level, smoking status, and systemic diseases were performed to examine the association between PPT and oral dryness. Further subgroup analysis stratified by number of missing teeth was performed. RESULTS: Oral dryness was present in 122 (21.6%) of 566 jaws in 73 (21.9%) of the 333 subjects. The mean (standard deviation) of the log PPT was 2.00 (0.26) in the subjects who perceived oral dryness and 2.04 (0.22) in those who did not. Oral dryness was associated with a lower log PPT, but the relationship was not significant (coefficient - 0.017; 95% confidence interval - 0.071, 0.038). Subjects with oral dryness and edentulous oral mucosa had a significantly lower PPT (coefficient - 0.145; 95% confidence interval - 0.283, - 0.006) than their partially dentate counterparts. CONCLUSION: There was a significant association of oral dryness with increased pressure pain sensitivity in the oral mucosa only in jaws with complete dentures. CLINICAL RELEVANCE: The approach to oral dryness could contribute to reduction of oral pain sensitivity.

[Factors related to the passive attitude of caregivers on dental care visit when elementary and junior high school children are diagnosed with dental caries].

Objectives　Early diagnosis and treatment are particularly important for children who have dental caries. It has been reported that some children are not taken to a dental clinic even though they are diagnosed with dental caries at school dental check-ups. The purpose of this study is to investigate factors related to the passive attitude of caregivers regarding dental care visits when elementary and junior high school children are diagnosed with dental caries.Methods　A cross-sectional study was conducted utilizing data from the 2016 Adachi Child Health Impact of Living Difficulty (A-CHILD) study. A questionnaire was administered to 1,994 parents of 4th and 6th grade students in elementary school, and 8th grade students in junior high school. Out of the 1,994 parents, 1,652 (83%) responded. Caregivers were asked whether they take their child to the dental clinic immediately if their child is diagnosed with dental caries. Those who answered "cannot take immediately" were defined as caregivers with a passive attitude towards dental care visits. Their reasoning was further probed by the questionnaire. The validity of the answer (i.e., taking their child to the dental clinic) was assessed with the child's untreated dental caries obtained from the results from the school dental health checkup. The number of children excluded in the analysis due to a lack of information on dental caries and/or the attitude of the parents was 1,613. A logistic regression analysis was performed to investigate the association between passive attitude on dental care visit and demographic factors (e.g., child's sex, grade, number of siblings, and household members), lifestyle (e.g., time home for caregiver, grandparent co-residence, skipping breakfast, snacking habits, sugar-sweetened beverage intake, frequency of teeth brushing, and parent-child relationship), and socioeconomic status (e.g., annual household income, educational attainment of caregiver, employment status of caregiver).Results　In total, 269 (16.7%) caregivers reported a passive attitude for the dental care visit of their child. The most frequent reason was "I don't have time to take my child to the dental clinic" (172 people, 55.8%). The passive attitude by the caregivers was associated with untreated decay for the child (P<0.001). The passive attitude of the caregiver on the dental care visit was associated with lower maternal educational attainment, skipping breakfast for the child, and lower frequency of brushing teeth. In elementary school children, the passive attitude of the caregiver on the dental care visit was also significantly associated with maternal employment, later time of getting home by the mother and a lack of interaction with children by the caregiver.Conclusion　The passive attitude of the caregiver as pertaining to the dental care visit of the child was associated with maternal socioeconomic background. Health promotion activities considering maternal socioeconomic background is needed.

The Causal Effect of Education on Tooth Loss: Evidence From United Kingdom Schooling Reforms.

Associations between education and oral health have frequently been reported, but until now there has been no causal evidence. Exploiting exogenous variation in the duration of schooling due to 1947 and 1972 reforms in mandatory schooling in the United Kingdom, we examined the causal relationship between education and tooth loss in older age. We conducted a cross-sectional study using data from waves 3 (2006-2007), 5 (2010-2011), and 7 (2014-2015) of the English Longitudinal Study of Ageing. We used a 2-stage least squares instrumental variable approach and included 5,667 respondents (average age = 67.8 years; 44.4% were men) in the analyses, of whom 819 (14.5%) had no teeth. The schooling reforms increased the duration of education by an average of 0.624 years (95% confidence interval: 0.412, 0.835). For respondents born within ±6 years of the pivotal cohorts, a 1-year increment of education causally reduced the probability of edentulism by 9.1 (95% confidence interval: 1.5, 16.8) percentage points. The effects were stronger for the 1947 reform than for the 1972 reform. Results were robust to broadening of the cohort bandwidth and functional form of the cohort trend. The findings suggest that investment in education produces improved oral health later in life.

Does Cigarette Smoking Increase Traffic Accident Death During 20 Years Follow-up in Japan? The Ibaraki Prefectural Health Study.

BACKGROUND: Annually, more than 1.2 million deaths due to road traffic accidents occur worldwide. Although previous studies have examined the association between cigarette smoking and injury death, the mortality outcome often included non-traffic accident-related deaths. This study aimed to examine the association between cigarette smoking and traffic accident death. METHODS: We conducted a prospective cohort study using data from the Ibaraki Prefectural Health Study conducted from 1993 through 2013. The cohort included 97,078 adults (33,138 men and 63,940 women) living in Ibaraki Prefecture who were aged 40-79 years at an annual health checkup in 1993. We divided participants into four smoking status groups: non-smokers, ex-smokers, and current smokers who smoked <20 and ≥20 cigarettes per day. Hazard ratios (HRs) of traffic accident death were calculated using a Cox proportional hazards model. RESULTS: During 20 years of follow-up, the average person-years of follow-up were 16.8 and 18.2 in men and women, respectively. Among men, after adjusting for age and alcohol intake, HRs for traffic accident death among current smokers of <20 cigarettes/day and ≥20 cigarettes/day compared to non-smokers were 1.32 (95% confidence interval [CI], 0.79-2.20) and 1.54 (95% CI, 0.99-2.39), respectively. In contrast, among women, we found no association between smoking status and traffic accident deaths. CONCLUSION: In this prospective cohort study, we found a positive association, though marginally significant, between smoking and traffic accident death among men in Japan. Among women, because of the smaller number of deaths among smokers, adequate estimation could not be obtained.