Identifying distinct subtypes of mother-to-infant bonding using latent profile analysis in a nationwide Japanese study

BACKGROUND

Mother-to-infant bonding (MIB) is foundational for nurturing behaviors and an infant's development. Identifying risk factors for difficulties or problems in MIB is vital. However, traditional research often dichotomizes MIB using cutoff thresholds, overlooking its underlying complexities. This research utilizes latent profile analysis (LPA) to discern MIB subtypes in a nationwide Japanese dataset.

METHODS

We conducted LPA on data from the Mother-to-Infant Bonding Scale (MIBS), collected from 3,877 postpartum women within one year of childbirth. To empirically validate the derived profiles, we examined their associated risk factors, focusing on sociodemographic, health, and perinatal variables.

RESULTS

Four distinct MIB profiles emerged. Profile 1 indicated minimal difficulties, while Profile 4 exhibited severe multifaceted difficulties. Profiles 2 and 3 showed moderate difficulties distinguished by lack of positive affection and presence of negative affection (especially indifference), respectively. Compared to Profile 1, women in Profiles 2-4 had a higher likelihood of postpartum depression and low family support. Each profile also presented unique risk factors: medium family support in Profile 2, maternal working status in Profile 3, and pre-pregnancy underweight status in Profile 4. Notably, both Profiles 3 and 4 were also linked to increased feelings of loneliness since the onset of the COVID-19 pandemic.

CONCLUSION

This study represents the first application of LPA to MIB, revealing distinct subtypes and their respective risk profiles. These insights promise to enhance and personalize early interventions for difficulties in MIB, affirming the necessity of acknowledging MIB's heterogeneity.

Poor oral health and dementia risk under time-varying confounding: A cohort study based on marginal structural models

BACKGROUND

Bidirectional association between oral health, including tooth loss and oral hypofunction, and cognitive impairment can induce time-varying confounding in association with dementia. This study aimed to investigate the association between oral health and the development of dementia among older adults, considering cognitive impairment as a time-varying confounder.

METHODS

This nine-year follow-up cohort study targeted independent older adults aged ≥65 years who participated in the Japan Gerontological Evaluation Study. The exposure variables were self-reported poor oral health (≤19 remaining teeth, edentulousness, chewing difficulty, swallowing problems, and xerostomia), which were assessed in 2010 and 2013. The outcome variable was the incidence of dementia between 2013 and 2019, which was obtained from the municipalities' administrative database. Furthermore, in 2010 and 2013, we considered cognitive impairment as a time-varying confounder and treated it based on a marginal structural model (MSM), including possible baseline confounders. Oral health and cognitive impairment were assessed using the items of Kihon checklist. We employed a Cox proportional hazards model with a stabilized inverse probability weight and estimated hazard ratios (HRs) and 95% confidence intervals (CIs).

RESULTS

Among 37,556 participants (mean age: 72.8 years [1 SD = 5.5], males: 46.8%), the dementia incidence rate was 2.2/100 person-year. The proportions of those with ≤19 remaining teeth, edentulousness, chewing difficulty, swallowing problems, and xerostomia were 61.3%, 11.0%, 24.4%, 14.7%, and 19.2%, respectively. From the regression analysis based on MSM, ≤19 remaining teeth (HR = 1.12, 95% CI = 1.03-1.23), edentulousness (HR = 1.20, 95% CI = 1.09-1.32), chewing difficulty (HR = 1.11, 95% CI = 1.02-1.21), and xerostomia (HR = 1.10, 95% CI = 1.01-1.20) were significantly associated with an increased risk of dementia; however, swallowing problems were not significantly associated with dementia onset (p > 0.05).

CONCLUSIONS

Even after considering time-varying confounding by cognitive function at baseline and follow-up, we observed significant associations between poor oral health and increased risk of dementia among older adults.

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. Dementia incidence during 2013-2019, smoking status (never, past/current) in 2010 and the number of remaining teeth (≤19, ≥20) in 2013 were the outcome, exposure and mediator, respectively. We used causal mediation analysis to fit the Cox proportional hazards model and estimated the hazard ratio (HR) and 95% confidence interval (CI) of the natural indirect effect (NIE) of smoking on dementia incidence through tooth loss and their mediated proportions.

RESULTS

Among 32,986 participants (mean age 72.6 years [1 SD = 5.4]; men 48.4%), the dementia incidence during follow-up was 2.11/100 person-years. Tooth loss significantly mediated the association between past/current smoking and dementia incidence; the NIE of fewer remaining teeth for past/current smokers compared to never smokers was HR = 1.03 (95% CI: 1.02-1.05), and the mediated proportion was 18.0%.

CONCLUSIONS

Tooth loss significantly mediates the association between past/current smoking and an increased risk of dementia among older adults.

Prevalence of dental visits in older Japanese adults receiving public assistance

OBJECTIVES

Exemption from paying dental care costs among recipients of public assistance contributes to universal health care coverage. Although this system might reduce the financial barriers to dental care among patients, there are still several other barriers for public assistance recipients. Therefore, this study examined whether receiving public assistance was associated with a higher prevalence of dental visits for any reason, treatment and prevention.

METHODS

Data were obtained from 16 366 respondents from the 2019 wave of a nationwide cohort study on older adults in Japan. Poisson regression analyses with robust error variance were used to examine the associations between receiving public assistance and dental visits, adjusting for number of teeth, dental pain, periodontal conditions, age, sex, number of family members, education, equivalent household income, working status, instrumental activities of daily living, medical conditions, depressive symptoms, instrumental support and geographical variations.

RESULTS

More than half of the non-recipients of public assistance visited a dentist for some reason in the past 6 months. Meanwhile, only 37% of the recipients visited a dentist. In addition, almost half of the non-recipients had treatment visits, while only 34% of the recipients visited. Furthermore, 46% of the non-recipients had dental visits for prevention, while 32% of the recipients had preventive visits. In the fully adjusted models, compared to non-recipients, public assistance recipients were 24% (Prevalence Ratio [PR]: 0.76, 95% Confidence Intervals [CI]: 0.64, 0.90), 23% (PR: 0.77, 95% CI: 0.65, 0.92) and 21% (PR: 0.79, 95% CI: 0.65, 0.95) less likely to have dental visits for any reason, treatment, and prevention, respectively.

CONCLUSIONS

Although recipients were exempted from dental treatment fees, receiving public assistance was associated with a lower prevalence of dental visits for any reason, treatment and prevention. Future studies should identify the barriers to accessing dental care among public assistance recipients to improve dental visits.

Socioeconomic status and incident depressive symptoms among older adults: A 3-year longitudinal study from the Japan Gerontological Evaluation Study

OBJECTIVES

The association between socioeconomic status (SES) and the onset of depressive symptoms has attracted considerable attention. However, few studies have simultaneously examined the association of multiple SES indicators, including "assets," with the onset of depressive symptoms. Therefore, this study examined the association of four SES indicators in old age ('years of education' 'equivalent income,' 'equivalent assets,' and 'the longest-held job') with new-onset depressive symptoms in a large Japanese dataset.

METHODS

This longitudinal study used panel data of cognitively and physically independent older adults from the Japan Gerontological Evaluation Study (JAGES) conducted in 2013 and 2016. Multivariate logistic regression analysis was conducted to examine the association of each SES indicator with new-onset depressive symptoms, and odds ratios and 95% confidence intervals (CIs) were calculated.

RESULTS

We analyzed the data of 40,257 older adults, with a mean age (± standard deviation) of 72.9 (±5.5) years. In the follow-up survey, 4292 older adults had new-onset depression symptoms (10.7%). 39.3% had 10-12 years of education. 36.9% had an equivalent income of up to JPY 1.99 million. 24.4% had equivalent assets of JPY 4-17.99 million. Most had a clerical job for the long time. Furthermore, fewer years of education (males: OR = 1.42, 95% CI = 1.22-1.64, p-value <0.001/females: 1.26, [1.09-1.47], p = 0.002), lower income (males: 1.64, [1.34-2.01], p < 0.001/females: 1.82, [1.49-2.22], p < 0.001), and fewer assets (males: 1.40, [1.16-1.68], p < 0.001/females: 1.21, [1.02-1.42], p = 0.025) resulted in higher odds of having new-onset depressive symptoms, even when other SES indicators were entered simultaneously.

CONCLUSIONS

All four SES indicators have an independent association with the development of new-onset depressive symptoms among older adults, reflecting different aspects of SES. The association between the "longest-held job" and new-onset depressive symptoms can be largely explained by other SES indicators. A multifaceted and lifetime approach is required to prevent the onset of depressive symptoms in old age.

Postpartum loneliness predicts future depressive symptoms: a nationwide Japanese longitudinal study

PURPOSE

The COVID-19 pandemic has intensified feelings of loneliness, especially among postpartum women. This nationwide Japanese longitudinal study assessed the impact of such feelings on depressive symptoms and mother-to-infant bonding difficulties (MIBD), two pivotal determinants of maternal and infant well-being.

METHODS

Starting with a baseline survey conducted between July and August 2021, we tracked 1254 postpartum Japanese women who initially reported minimal depressive symptoms (i.e., Edinburgh Postnatal Depression Scale < 9) and MIBD (i.e., Mother-to-Infant Bonding Scale < 5), over a follow-up period of approximately 6 months. Baseline loneliness was evaluated with the UCLA Loneliness Scale Short-Form (UCLA-LS3-SF3).

RESULTS

Forty-nine percent of the sample reported the presence of baseline feelings of loneliness. After propensity score matching on sociodemographics and various pregnancy, childbirth, and COVID-19-related aspects, baseline loneliness was associated with increased risks of later depressive symptoms but not MIBD. Using restricted cubic spline logistic regression and considering loneliness as a continuous variable, we found a positive increasing quadratic relationship with depressive symptoms. As loneliness increased, so did the risk of later depressive symptoms. However, there was no significant association between loneliness and MIBD. These results were confirmed through a sensitivity analysis using inverse probability weighting to address attrition bias.

CONCLUSION

Feelings of postpartum loneliness are associated with future risks of depressive symptoms. The data suggests that addressing loneliness in postpartum women early is crucial to safeguarding their well-being and that of their infants.

Association between the telecommuting environment and somatic symptoms among teleworkers in Japan

OBJECTIVES

This study aimed to clarify the association between telecommuting environments and somatic symptoms among teleworkers in Japan.

METHODS

This cross-sectional study, conducted from September 27 to October 29, 2021, used data from the Japan COVID-19 and Society Internet Survey (JACSIS study) in Japan. Of the 31 000 male and female respondents, who were Japanese residents aged 15-79 years and were randomly selected from the panel members of an internet survey company, 4569 home-based teleworkers were finally included in the analysis; 26 431 respondents who met the exclusion criteria were excluded. The analysis included 4 cut-offs (≥4, 8, 12, and 16 points) for somatic symptoms on the Somatic Symptom Scale-8 as objective variables, and the telecommuting environment, such as having adequate desk light and a quiet environment, as explanatory variables. Adjusted Poisson regression analysis was conducted using demographic variables as covariates.

RESULTS

The prevalence ratio (PR) for somatic symptoms increased significantly as the number of poor telecommuting conditions increased, regardless of the cut-off value for somatic symptoms or the frequency of teleworking. In the telecommuting environment, the PR for somatic symptoms was significantly higher for the following 6 items: poor teleworking space to concentrate, inadequate foot space, poor communication environment, poor space for relaxation, noise, and inappropriate temperature and humidity.

CONCLUSIONS

These results suggest that for home-based teleworkers, the more inadequate the telecommuting environment, especially in the aforementioned 6 areas, the higher the likelihood of somatic symptoms. Improving these environments may be useful in preventing various somatic symptoms.

Family Pharmacy and Medication Adherence Among Older Adults in Japan: A Cross-Sectional Study of JAGES 2019

OBJECTIVES

Poor medication adherence among older adults is a global concern as it causes adverse drug interactions and inappropriate dosing. This study aimed to assess the association between family pharmacy and medication adherence among older adults.

METHODS

The Japan Gerontological Evaluation Study was a cross-sectional study of 18,792 people aged ≥65 years living in 61 municipalities in 25 prefectures who participated in a survey conducted in 2019 and did not require long-term care. Self-reported questionnaires were administered to evaluate whether the participants "always received medicines from the same pharmacy" and whether they had unused medicines. Modified Poisson regression was used to examine the association after adjusting for confounders.

RESULTS

Unused medicines were present in 89.9% of the "have group" (individuals who always received their medicines from the same pharmacy). This group had a lower prevalence of unused medicines (prevalence ratio [PR] = 0.87, 95% confidence interval [CI]: 0.82-0.92) than the "none group" (individuals who did not always receive their medicines from the same pharmacy). In the stratified analysis by education level, the prevalence of unused medicines was lower among those with low levels of education (≤9 years: PR = 0.82, 95% CI: 0.71-0.96; 10-12 years: PR = 0.81, 95% CI: 0.74-0.88).

DISCUSSION

Older adults who "always received medicines from the same pharmacy" had a lower prevalence of unused medicines, especially those with low levels of education. Thus, "always receiving medicines from the same pharmacy" may be effective in reducing the proportion of unused medicines and improving medication adherence.

Does eating with others promote happiness among older adults living alone? A 3-year longitudinal study of the Japan gerontological evaluation study

OBJECTIVE

Living a happy life is an essential issue for old adults. However, how eating with others contributes to happiness and whether this association is different by living arrangements or not is unknown. The current study examined the relationship between the frequency of eating with others and happiness among older adults according to their living arrangements using 3-year longitudinal data.

METHODS

The analyzed sample comprised 18,727 people (10,920 males and 7807 females) with low happiness (0-7 points on score of 0-10 points) from Japan Gerontological Evaluation Study (JAGES) in 2016. Our exposure was the frequency of eating with others: rarely, a few times a year, a few times a month, and a few times a week or more. We performed Modified Poisson Regression to examine the association between the frequency of eating with others and high happiness (8-10 points) in 2019 stratified by living arrangement (living alone/with others).

RESULTS

A total of 4352 (23.2%) people showed high happiness in 2019. After adjusting for age, sex, marital status, education, household income, social participation, illnesses under treatment, and depressive symptoms in 2016, the cumulative incidence ratio (CIR) for high happiness in 2019 among people living alone was more significant, that is, 1.28 (95% confidence intervals: 0.88-1.87), 1.50 (1.05-2.14), and 1.82 (1.26-2.63), than 1.28 (1.11-1.48), 1.30 (1.12-1.50), and 1.33 (1.16-1.52) among people living with others for those who ate with others a few times a year, a few times a month, and a few times a week or more compared to those who rarely ate with others, respectively. The interaction between the frequency of eating with others and living arrangements was statistically significant. The trend test showed that higher frequency of eating with others was significantly associated with high happiness.

CONCLUSIONS

Eating with others was associated with improved happiness among older adults, with such an association being stronger among people living alone.

Participation in Community Gathering Places and Subsequent Health and Well-Being: An Outcome-Wide Analysis

Background and Objectives

Evidence remains inadequate regarding the benefits of participation in community gathering places, which is Japan's primary strategy for preventing functional disability in older adults, in other domains of health and well-being. This longitudinal study examined the associations of participation in community gathering places with an array of subsequent health and well-being outcomes among older adults.

Research Design and Methods

We used 3-wave data (2013, 2016, and 2019) from Japan Gerontological Evaluation Study (n = 5 879 or 4 232 depending on the outcome). Our exposure was participation in community gathering places in 2016. We assessed 34 health/well-being outcomes in 2019 across 6 domains. We adjusted for pre-baseline covariates including prior outcome values in 2013.

Results

Compared with nonparticipation, participation in community gathering places was associated with some outcomes in the following 3 domains: physical/cognitive health (better higher-level functional capacity), social well-being (more frequent participation in hobby groups, senior citizens clubs, learning or cultural groups, and seeing more friends within a month), and prosocial/altruistic behaviors (more frequent participation in volunteering; after Bonferroni correction as p < .0015, .05/34).

Discussion and Implications

Evidence was mixed and more modest for the outcomes in three other domains, mental health, psychological well-being, and health behaviors. Promoting participation in community gathering places may not only fulfill its original goal (ie, preventing functional disability) but also enhance other domains of human well-being, potentially by increasing social interactions.

Social isolation, loneliness, and their correlates in older Japanese adults

BACKGROUND

Loneliness and social isolation are elevated in older adults and associated with a range of detrimental outcomes. Despite this, there has been little research on these phenomena or on similarities and differences in their occurrence or combination in older Japanese adults. The current study aims to (i) determine what factors are associated with social isolation and loneliness among older adults in Japan; and (ii) describe the characteristics of individuals who are socially isolated but not lonely, as well as those who feel lonely but are not socially isolated.

METHODS

Data were analysed from 13 766 adults aged ≥65 years who participated in the 2019 wave of the Japan Gerontological Evaluation Study. Poisson regression analysis was used to examine associations.

RESULTS

Among older Japanese adults, the attributes of higher age, male gender, lower socioeconomic status, being a welfare recipient, and having depressive symptoms were associated with social isolation, while lower socioeconomic status, unemployment, welfare receipt, and poor physical and mental health were associated with loneliness. In addition, better educated, and mentally and physically healthy people were less likely to feel lonely even when socially isolated, while people who were not working and who had mental or physical health problems were more likely to feel lonely even if they were not socially isolated.

DISCUSSION

Our results indicate that in order to reduce unwanted social isolation and loneliness among older Japanese adults, in the first instance the focus should be on those individuals who are socioeconomically disadvantaged and unhealthy.

Oral function and cumulative long-term care costs among older Japanese adults: a prospective 6-year follow-up study of long care receipt data

OBJECTIVES

This study evaluated the relationship between status of oral function and related long-term care service costs.

DESIGN

This was a prospective 6-year follow-up study of previous survey data.

SETTING

The data were obtained from the Japan Gerontological Evaluation Study conducted between 2010 and 2011.

PARTICIPANTS

The participants were functionally independent older adults in 12 municipalities across Japan.

INTERVENTIONS

Care service benefit costs were tracked over 6 years using publicly available claims records (n=46 616) to monitor respondents' cumulative care costs.

PRIMARY AND SECONDARY OUTCOME MEASURES

The primary outcome variable was the cumulative cost of long-term care insurance services during the follow-up period. We adjusted for the presence or absence of oral function problems, age, sex, physical function and socioeconomic and lifestyle background at the time of the baseline survey.

RESULTS

Tobit analysis revealed that, compared with those with no oral function problems, cumulative long-term care service benefit costs for those with one, two or three oral function problems were approximately US$4020, US$4775 and US$82 92, respectively, over 6 years. Compared with those with maintained oral function, there was a maximum difference of approximately US$8292 in long-term care service costs for those with oral function problems. With increase in number of oral function problems, there was a concomitant elevation in the cost of long-term care.

CONCLUSIONS

Oral function in older people was associated with cumulative long-term care insurance costs. The oral function of older people should be maintained to reduce future accumulated long-term care insurance costs. Compared with those with maintained oral function, there was a maximum difference of approximately US$8292 in long-term care service costs for those with oral function problems. The cost of long-term care was amplified as oral problems increased.

Suicidal ideation and suicide attempts among older recipients of public welfare assistance in Japan

BACKGROUND

The high suicide rate among older adults is an important public health issue. Financial insecurity has been linked to suicidal behaviour. Despite this, as yet, there has been little research on suicide-related behaviours among older recipients of public welfare. This study will examine if suicidal ideation and suicide attempts are more prevalent in older recipients of public welfare assistance in Japan.

METHODS

This cross-sectional study analysed data from 16 135 adults aged ≥65 years who participated in the 2019 wave of the Japan Gerontological Evaluation Study. Information was obtained on receiving public welfare assistance, lifetime suicidal ideation and attempts, and a variety of covariates. Poisson regression analysis with robust variance estimates was used to examine associations.

RESULTS

Suicidal ideation was reported by 4.8% of the participants, while the corresponding figure for attempted suicide was 2.2%. In fully adjusted analyses public welfare recipients had an almost 1.5 times higher prevalence of lifetime suicidal ideation (prevalence ratio, PR 1.47, 95% CI 1.02 to 2.13), and an almost two times higher prevalence of attempted suicide (PR 1.91, 95% CI 1.20 to 3.04) when compared with their counterparts not receiving public welfare assistance.

CONCLUSION

Older recipients of public welfare have a higher prevalence of suicidal behaviour in Japan. An urgent focus is now warranted on this vulnerable population to determine the specific factors underlying this association.