Frequency of laughter and depression onset among older adults: A 6-year longitudinal study from the Japan Gerontological Evaluation Study.

Background: Laughter has been associated with mental and physical health benefits, but longitudinal evidence on whether laughter in daily life protects against depression remain limited. This study aimed to examine whether the frequency of laughter in daily life is associated with the risk of depression onset among older adults.

Methods: We analyzed data from 32,666 adults aged ≥65 years participating in the Japan Gerontological Evaluation Study, a three-wave cohort conducted over six-years.

Socioeconomic Inequalities in Oral Frailty Among Older Adults: A Causal Mediation Analysis on the Role of Prevention From Tooth Loss.

Background: Although social inequalities in oral health have been suggested, the link between socioeconomic status (SES) and oral frailty (OF) remains unclear. We aimed to investigate the inequalities in OF according to SES and the extent to which inequalities are mitigated by preventing tooth loss.

Methods: We used cross-sectional data from 21 542 functionally independent participants aged ≥ 65 (48.

Chewing difficulty, swallowing problems, xerostomia and cause-specific mortality among older adults: A 7-year follow-up JAGES cohort study.

Aim: Although various poor oral health conditions have been reported to be associated with an increased all-cause mortality risk, a comprehensive investigation of the causes of death is limited. This study aimed to investigate the association between poor oral function and mortality due to various causes in older adults.

Methods: This 7-year follow-up cohort study used data from the Japan Gerontological Evaluation Study.

Dietary diversity and the risk of metabolic syndrome in a Japanese population: an analysis of baseline cross-sectional data from the J-MICC study.

Background: With the increasing burden of metabolic syndrome, it is crucial to focus on lifestyle factors to reduce the risk of metabolic syndrome.

Objectives: This study aims to quantify the associations between dietary diversity and the risk of metabolic syndrome among the Japanese population.

Methods: This study was conducted using baseline data from the Japan Multi-Institutional Collaborative Cohort (J-MICC) study.

Comparison of polygenic risk scores for type 2 diabetes developed from different ancestry groups.

Polygenic risk scores (PRS) are useful for assessing disease risk; however, knowledge about their effectiveness among Asian and other populations is limited. This study aimed to compare the classification accuracy of PRSs for type 2 diabetes (T2D-PRS) developed from different ancestry groups using genotype data from 14,083 Japanese participants. Participants' scores were calculated using T2D-PRS models, and logistic regression analysis and receiver operating characteristic curves were assessed.

Impact of posterior occlusal contact loss on cardiovascular disease using a Japanese claims database.

Cardiovascular disease (CVD) is a global health concern; however, its association with the posterior occlusal contact remains unexplored. This study investigated the association between posterior occlusal contact and CVD risk in a large Japanese cohort and examined whether the loss of posterior occlusal contact in individuals with at least 20 teeth was a distinct CVD risk factor. Using Japanese health insurance claims data from 1,209,997 adults aged ≥ 40 years without prior CVD history (April 2016-March 2022), participants were categorized using the Eichner classification to assess posterior occlusal contact.

Differences in health care expenditure due to the comorbidity status of periodontal disease and diabetes mellitus.

Background: To investigate the differences in health care expenditure (HCE) due to the comorbidity status of periodontal disease (PD) and diabetes mellitus (DM).

Methods: This cohort study used health care claims and oral health screening data to identify participants with PD or DM and followed them for 1 year to assess their HCE. PD and DM were determined based on PD screening and medical claims data, respectively.

Periodontal Care Is Associated With a Lower Risk of Dialysis Initiation in Middle-Aged Patients With Type 2 Diabetes Mellitus: A 6-Year Follow-Up Cohort Study Based on a Nationwide Healthcare Database.

Objective: To investigate the association between dental attendance with periodontal care and the risk of dialysis initiation in patients with type 2 diabetes mellitus (T2D).

Methods: This retrospective cohort study used data from the Japan Medical Data Center (JMDC) claims database (January 2015 to August 2022). Patients with T2D, aged 40-74, were included.

Longitudinal association between posterior occlusal contact and dementia development in a large retrospective cohort study using a Japanese claims database.

This study examines the association between posterior occlusal contact and the risk of dementia development in the Japanese population, utilizing Eichner classification to evaluate occlusal status. Data from Japanese health insurance claims were analyzed for the period from April 2016 to March 2022. Participants had undergone specific health checkups, had no prior history of dementia, and were classified according to their dental occlusal contact.

Food group intakes and high-sensitivity C-reactive protein among community-dwelling Japanese adults: a cross-sectional study.

Objective: Healthy dietary patterns have been linked to lower levels of chronic inflammation. The present study aimed to investigate the associations between food group intakes and high-sensitivity C-reactive protein (hsCRP) among community-dwelling adults.

Design: Cross-sectional.

Secondhand Tobacco Exposure Assessed Using Urinary Cotinine Among 10-Year-Old Children in Japan: An 11-Year Repeated Cross-sectional Study.

Introduction: The emergence of heated tobacco products (HTPs) has made it important to monitor HTP-generated aerosols in addition to combustible cigarette (CC) smoke as a source of secondhand tobacco (SHT) exposure. We investigated the trend of SHT exposure in school-aged children and assessed whether SHT exposure depended on household tobacco use status.

Aims And Methods: This repeated cross-sectional study from 2011 to 2021 (15 927 participants) was based on data from an annual survey of fourth-grade students (aged 10 years) in Kumagaya City, Japan.

Validity of claims-based definition of number of remaining teeth in Japan: Results from the Longevity Improvement and Fair Evidence Study.

Background: Secondary healthcare data use has been increasing in the dental research field. The validity of the number of remaining teeth assessed from Japanese dental claims data has been reported in several studies, but has not been tested in the general population in Japan.

Objectives: To evaluate the validity of the number of remaining teeth assessed from Japanese dental claims data and assess its predictability against subsequent health deterioration.

Changes in the Utilization of Outpatient and Visiting Dental Care and Per-attendance Care Cost by Age Groups During COVID-19 Pandemic Waves in Japan: A Time-series Analysis From the LIFE Study.

Background: The influence of the coronavirus disease 2019 (COVID-19) pandemic on dental care utilization may have differed according to individual characteristics or type of dental care provision. This study aimed to evaluate the changes in dental care utilization and per-attendance costs by age group and type of dental care during the COVID-19 pandemic in Japan.

Methods: This time-series study used healthcare insurance claims data from 01/07/2019 to 09/27/2021 (143 weeks) from nine municipalities in Japan.

Tooth loss mediates the association between smoking and an increased risk of dementia among older adults: The JAGES prospective cohort study.

Aim: Tooth loss has various causes; however, its cause-specific effects on health outcomes remain unclear. This study evaluated whether the association between past/current smoking and risk of dementia was mediated by tooth loss.

Materials And Methods: This 9-year-follow-up prospective cohort study targeted adults aged ≥65 years.

Bivalent mRNA vaccine effectiveness against COVID-19 among older adults in Japan: a test-negative study from the VENUS study.

Background: Bivalent COVID-19 vaccines have been implemented worldwide since the booster vaccination campaigns of autumn of 2022, but little is known about their effectiveness. Thus, this study holistically evaluated the effectiveness of bivalent vaccines against infection in older adults in Japan.

Methods: We adopted the test-negative design using COVID-19 test data of individuals, aged ≥ 65 years, residing in three municipalities in Japan, who underwent tests in medical institutions between October 1 and December 30, 2022.

Association Between Awareness of Limiting Food Intake and All-cause Mortality: A Cohort Study in Japan.

Background: Improving diets requires an awareness of the need to limit foods for which excessive consumption is a health problem. Since there are limited reports on the link between this awareness and mortality risk, we examined the association between awareness of limiting food intake (energy, fat, and sweets) and all-cause mortality in a Japanese cohort study.

Methods: Participants comprised 58,772 residents (27,294 men; 31,478 women) aged 35-69 years who completed baseline surveys of the Japan Multi-Institutional Collaborative Cohort Study from 2004 to 2014.

Reduced number of teeth with and without dental prostheses and low frequency of laughter in older adults: Mediation by poor oral function.

Purpose: Laughter is expected to have health-protective effects, but the potential link between tooth loss and laughter remains unclear. Therefore, this study aimed to examine the association between tooth loss and a low frequency of laughter among older adults in Japan, to elucidate whether this association could be mitigated by dental prostheses, and to evaluate the magnitude of the association mediated by poor oral function.

Methods: We used cross-sectional data from 157,708 functionally independent participants aged ≥65 years (46.

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.

Effectiveness of COVID-19 vaccines against infection in Japan: A test-negative study from the VENUS study.

Background: Although the effectiveness of coronavirus disease 2019 (COVID-19) vaccines is a crucial public health concern, evidence from Western Pacific countries is limited, including Japan. This study aimed to estimate the COVID-19 vaccines effectiveness (VE) against infection during the Delta variant predominance (July-September 2021) in Japan.

Methods: We performed a test-negative study using COVID-19 test data of ≥20-year-old residents in four municipalities who were tested in medical institutions between July 1 and September 30, 2021.