Background: New tobacco products, particularly heated tobacco products (HTPs), have been introduced across several international markets as alternatives to combustible products, such as cigarettes. However, there are limited studies on physicians’ perceptions of HTPs. This study analyzes the awareness of HTPs among physicians and assesses their concerns and attitudes toward patients using HTPs.

Methods: A self-administered questionnaire was sent to a sample of 7,500 member physicians (6,000 male and 1,500 female) from the Japan Medical Association (JMA). The smoking status of physicians was categorized as never smokers, ever HTP smokers, current HTP smokers, and ever and current smokers of other products. Physicians’ awareness and attitudes toward patients using HTPs were analyzed using descriptive statistics. The correlation between the outcomes was examined using logistic regression models, whereas physicians’ concerns about HTPs were analyzed using descriptive statistics.

Results: Data were obtained from 5,492 physicians (21.9% women; aged 60.4; standard deviation, 12.1 years) with a response rate of 74.6%. Overall, 76.7% of the physicians had awareness of HTP, and about half of whom asked patients about using HTPs. Physicians who took longer to discuss cessation were more likely to discourage patient use. Smoking status was associated with discouraging HTP use in patients. Physicians who had experience with HTP use were primarily concerned about the products’ long-term safety and less about product regulation.

Conclusion: Japanese physicians do not have sufficient information and knowledge about HTPs. Therefore, evidence-based guidelines are required to support physicians in advising patients against HTP use.

Background: Progress in reducing the global low birthweight (LBW) has been insufficient. Although the focus has been on preventing preterm birth, evidence regarding LBW in term births is limited. Despite its low preterm birth prevalence, Japan has a higher LBW proportion than other developed countries. This study aimed to examine the prevalence of LBW in term singleton births and its associated factors using a national database.

Methods: We retrospectively analyzed the data of neonates registered in the Japan Society of Obstetrics and Gynecology Successive Pregnancy Birth Registry System who were born 2013–2017. Exclusion criteria included stillbirths, delivery after 42 gestational weeks, and missing data. Logistic regression analyses were performed to investigate the maternal and perinatal factors associated with LBW in term singletons using the data of 715,414 singleton neonates.

Results: The overall prevalence of LBW was 18.3%, and 35.7% of LBWs originated from singleton term pregnancies. Multiple logistic regression analyses indicated that both modifiable and non-modifiable factors were independently associated with LBW in term neonates. The modifiable maternal factors included pre-pregnancy underweight, inadequate gestational weight gain, and smoking during pregnancy, while the non-modifiable factors included younger maternal age, nulliparity, hypertensive disorders of pregnancy, cesarean section delivery, female offspring, and congenital anomalies.

Conclusion: Using the Japanese pregnancy birth registry data, more than one-third of LBWs were found to originate from singleton term pregnancies. Both modifiable and non-modifiable factors were independently associated with LBW in term neonates. Prevention strategies on modifiable risk factor control will be effective in reducing LBW worldwide.

Background: The association between hobby engagement and risk of dementia reported from a short-term follow-up study for individuals aged ≥65 years may be susceptible to reverse causation. We examined the association between hobby engagement in age of 40–69 years and risk of dementia in a long-term follow-up study among Japanese, including individuals in mid-life, when the majority of individuals have normal cognitive function.

Methods: A total of 22,377 individuals aged 40–69 years completed a self-administered questionnaire in 1993–1994. The participants answered whether they had hobbies according to the three following responses: having no hobbies, having a hobby, and having many hobbies. Follow-up for incident disabling dementia was conducted with long-term care insurance data from 2006 to 2016.

Results: During a median of 11.0 years of follow-up, 3,095 participants developed disabling dementia. Adjusting for the demographic, behavioral, and psychosocial factors, the multivariable hazard ratios of incident disabling dementia compared with “having no hobbies” were 0.82 (95% confidence interval [CI], 0.75–0.89) for “having a hobby” and 0.78 (95% CI, 0.67–0.91) for “having many hobbies”. The inverse association was similarly observed in both middle (40–64 years) and older ages (65–69 years). For disabling dementia subtypes, hobby engagement was inversely associated with the risk of dementia without a history of stroke (probably non-vascular type dementia), but not with that of post-stroke dementia (probably vascular type dementia).

Conclusion: Hobby engagement in both mid-life and late life was associated with a lower risk of disabling dementia without a history of stroke.

Background: Desired longevity represents how strongly people esteem possible extensions of their own lifetime. The association between desired longevity and mortality risk has been reported in only one prospective study, which examined a small sample of older participants. We aimed to examine the hypothesis that desired longevity at middle-age predicted long-term survival.

Methods: In the prospective cohort study, residents aged 40–64 years were asked how long they would like to live and asked to choose one from three options: longer than, as long as, or shorter than the life expectancy. We used Cox proportional hazards model to calculate the hazard ratios (HRs) and 95% confidence intervals (CIs) for all-cause and cause-specific mortality according to the three groups for desired longevity, treating the “longer than” group as the reference. We conducted mediation analysis to investigate the mechanism for the association between desired longevity and mortality.

Results: We recruited 39,902 residents to the study. Risk of all-cause mortality was significantly higher in the “shorter than” group (HR 1.12; 95% CI, 1.04–1.21). The association was independent of sex, age, marital status, education, medical history, and health status. Regarding cause of death, mortality risk of cancer (HR 1.14; 95% CI, 1.00–1.29) and suicide (HR 2.15; 95% CI, 1.37–3.38) were also higher in the “shorter than” group. The unhealthy lifestyle mediated this association with all-cause mortality by 30.4%.

Conclusion: Shorter desired longevity was significantly associated with an increased risk of all-cause mortality, and mortality from cancer and suicide. Lifestyle behaviors particularly mediated this association.

Background: Little is known about the association between a plant-based diet and the risk of gallstone disease (GD), especially in developing counties. We tested the hypothesis that shifting dietary patterns would be related to the risk of GD, and that the Mediterranean diet (MED) adjusted for China would be beneficial for lowering risk of GD.

Methods: Data were extracted from the baseline survey of the China Multi-Ethnic Cohort study. An alternative Mediterranean diet (aMED) score was assessed based on a food frequency questionnaire, and three posteriori dietary patterns (the modern dietary pattern, the coarse grain dietary pattern, and the rice dietary pattern) were identified using factor analysis. Multivariable logistic regression models were developed to evaluate the association between dietary patterns and GD risks.

Results: A total of 89,544 participants were included. The prevalence of GD was 7.5%. Comparing the highest with lowest quintiles, aMED was associated with an increased risk of GD (OR 1.13; 95% CI, 1.04–1.24; P_trend = 0.003), whereas the rice dietary pattern was inversely related to GD risk (OR 0.79; 95% CI, 0.71–0.87; P_trend < 0.001). In stratified analysis, the rice dietary pattern had a stronger inverse association in the subgroups of females, older, urban, and overweight participants, and those with diabetes—factors associated with higher rates of GD in previous studies.

Conclusion: Higher adherence to the rice dietary pattern was associated with a lower risk of GD. For high-risk populations, making some shift to a traditional agricultural diet might help with primary prevention of GD.

Background: Having siblings may foster sociality; however, little is known about whether sibling number determines social capital, the resources obtained through social networks. We examined the association between sibling number and social capital among Japanese parents rearing schoolchildren.

Methods: We used cross-sectional data from the 2018 and 2019 Adachi Child Health Impact of Living Difficulty (A-CHILD) study, targeting all primary and junior high school students and their parents in Adachi, Tokyo, Japan (n = 8,082). Individual-level social capital was evaluated by assessing caregivers’ social cohesion, social support, and group affiliation. All analyses were adjusted for age and sex.

Results: An inverse U-shaped association was found between sibling number and social capital. Adults who grew up with one or two, but not three or more siblings had greater social support (coefficient = 0.23; 95% confidence interval [CI], 0.06–0.40 and coefficient = 0.46; 95% CI, 0.29–0.64, respectively) than those who grew up as an only child, after covariate adjustment. Adults who grew up with two or three, but not one or four or more siblings had greater group affiliation (coefficient = 0.09; 95% CI, 0.03–0.16 and coefficient = 0.09; 95% CI, 0.01–0.18, respectively) than those who grew up as an only child, after covariate adjustment. Sibling number was not associated with social cohesion.

Conclusion: Growing up with one to three siblings was associated with higher social capital in adulthood than being an only child. Having siblings may provide an opportunity to foster social capital.