近藤 克則

Interventions that involve key aspects of community organizing, such as quantitative community assessments and organizational partnership support for the community, may promote residents' health. We evaluated the effectiveness of this form of intervention on mortality and its variability across individual-level household equivalized income tertiles, comparing 52,858 residents aged 65 and above in 12 intervention municipalities to 39,006 residents in nine control municipalities in Japan. During 1,166 days of follow-up, the adjusted hazard ratio for cumulative mortality among men in the intervention municipalities was 0.92 (95% confidence interval: 0.86, 0.99) compared to those in the control group, with similar results being observed across all income levels. Active utilization of data to evaluate communities and building intersectoral partnerships might lower older male residents' mortality risk, regardless of their income status.

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 (JAGES) data, including participants aged ≥65 years. The outcome was death between August 2010 to 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 (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.

OBJECTIVES: Elder abuse is a growing global public health concern. Previous studies have reported that elder abuse increases the risk of dementia; however, to the best of our knowledge, no studies have investigated the association between different types of abuse and dementia onset yet. This study, therefore, investigated the association between physical, psychological, and financial abuses and dementia onset in independent older adults in Japan. METHODS: A 6-year prospective cohort data from the Japan Gerontological Evaluation Study (JAGES) were collected in 2010 through a mail survey conducted among 5,674 men and 6,562 women aged ≥65 years across Japan. Dementia was assessed using the nationally standardized dementia scale proposed by the Ministry of Health, Labor and Welfare. Poisson regression analysis was performed separately for each type of abuse to calculate the incidence rate ratios and 95% confidence intervals. RESULTS: During follow-up, 552 (9.7%) men and 728 (11.1%) women developed dementia. After adjusting for potential confounders, participants who experienced financial abuse were 1.53 (1.09-2.16) times more likely to develop dementia than those who did not. On the other hand, participants who experienced physical abuse were 1.53 (0.92-2.56) times more likely and those who experienced psychological abuse were 0.98 (0.82-1.17) times less likely to develop dementia than participants who did not experience such abuses. However, the difference was not significant. CONCLUSION: Financial abuse may promote dementia among older adults in Japan, suggesting that preventing this abuse may help prevent dementia onset. However, further studies with larger data sets are warranted.

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.

目的 本研究の目的は二つである。第一に,要介護認定を受けていない65歳以上の高齢者を対象に,健康関連QOL尺度のひとつであるEQ-5D-5Lを用いて,現在の就労状況とQOL値の関連性を明らかにすることである。第二に,これまで最も長く勤めた職種(以下,最長職)別に,現在の就労状況とQOL値の関連性を明らかにすることである。方法 本研究は日本老年学的評価研究(JAGES)が2016年に実施した「健康とくらしの調査」データを用いた。回答者のうちADLに支障がなく,かつ健康状態の調査項目(EQ-5D-5L)に回答のあった17,695人を対象に解析を行った。EQ-5D-5LのQOL値を算出するために,[歩行][着替え][ふだんの活動][痛み・不快感][不安・ふさぎこみ]の5つの項目を各5段階で評価した。得られた回答を日本語版EQ-5D-5Lの換算表(タリフ)を用いてQOL値に変換し,高齢者の就労状況とQOL値の関連性を解析した。さらに,最長職別に就労状況とQOL値との関連性を解析した。結果 性別,年齢,教育歴,婚姻状態,世帯の資産,くらし向きを調整したうえでも,就労している群に比べて,退職した(就労していない)群のQOL値は有意に低かった(-0.010,p<0.01)。また,最長職別には,自営職(農林漁業以外)のみ就労している群に比べて,退職した(就労していない)群で有意に低かった(-0.067,p<0.01)。結論 QOL値は就労している群に比べて,退職した(就労していない)群で有意に低かったことから,高齢者の就労継続は,高齢期のQOLの維持向上に寄与している可能性があることが示唆された。(著者抄録)

AIM: We prospectively examined the association between leisure activities and changes in instrumental activities of daily living (IADL) among participants of the Japan Gerontological Evaluation Study (JAGES). METHODS: We analyzed data collected from 49 732 JAGES participants (23 359 men and 26 373 women), aged ≥65 years, from 24 municipalities in Japan. MEASUREMENTS: Baseline data were obtained for 25 types of leisure activities in which the cohort members participated. Baseline (2010) and follow-up (2013) data on IADL were collected - the outcome indicated changes in IADL scores from 2010 to 2013. We regressed changes in IADL scores from the 2010 to 2013 to the number of leisure activities. RESULTS: Older adults who engaged in more leisure activities had higher changes in IADL scores than those who engaged in fewer leisure activities: the β values (95% confidence interval [CI]) of the IADL scores were 0.001 [-0.04-0.04], 0.04 [0.01-0.08], 0.09 [0.05-0.13], 0.09 [0.05-0.14], 0.08 [0.02-0.13], and 0.13 [0.07-0.18] for having one, two, three, four, five, and more than six types of leisure activities (P for trend <0.001), respectively. Similar associations were found for different types of leisure activities, including predominantly physical and cultural activities. Statistically significant linear trends were obtained among the group, solitary, and other leisure activity subgroups (P for trend <0.05). CONCLUSIONS: Encouraging engagement in leisure activities may promote maintenance of IADL among older populations. Different types of leisure activities appear to have similar positive impacts on IADL. Geriatr Gerontol Int 2022; 22: 152-159.

While laughter is evoked mainly in social contexts, the potential link between laughter in daily life and health benefits is unclear. This study aimed to examine the association between laughter in daily life and the onset of functional disability among older adults in Japan. Data were obtained from a 6-year follow-up cohort of 12,571 participants (46.1% male) in the Japan Gerontological Evaluation Study, aged ≥65 years, who could independently perform daily activities. We evaluated their laughter in daily life from three perspectives: the types of situations in which people laugh, the number of situations in which people laugh with others, and the persons with whom people laugh. Using the Cox proportional hazards model, the risk of functional disability was estimated. A total of 1420 functional disabilities were observed during follow-up. After adjusting for potential confounders, participants who laughed with others (e.g., during conversations with friends) were at a reduced risk of functional disability (hazard ratio, 0.77; 95% confidence interval, 0.65-0.92) than those who laughed alone (e.g., during watching television). Similarly, the number of situations to laugh with others was inversely associated with the risk of functional disability (Ptrend < 0.001). Laughing in a conversation with friends reduced the risk of functional disability by approximately 30% compared to laughing alone. Overall, laughing with others was associated with a reduced risk of functional disability. Having more situations to laugh with others or at least the situation to laugh with friends might contribute to reducing the risk of functional disability later in life.

PURPOSE: Adverse childhood experiences (ACEs) have been linked to diminished health achievement across the life course. However, few studies have rigorously investigated the role of adult socioeconomic status (SES) as a mediator and an effect modifier of the association between ACEs and late-life depression. We used a four-way decomposition analysis to examine the relative contributions of mediation and interaction by low adult SES to the association between ACEs and late-life depression. METHODS: Data came from two waves (2013 and 2016) of the Japan Gerontological Evaluation Study, a nationwide cohort of older people (n = 7271). ACEs were determined as ≥ 2 experiences of the following: parental loss, parental divorce, parental mental illness, domestic violence, physical abuse, psychological neglect, psychological abuse, and economic disadvantage. Low adult SES was defined as earning < 2 million yen of income and < 10 years of schooling. Depressive symptoms were assessed using the Geriatric Depression Scale. RESULTS: Controlled direct effect (coefficient 0.28; 95% CI 0.08-0.46) accounted for 69.1% of the total effect, which was greater than the other three estimates for the decomposed effects (reference interaction 20.8%, mediated interaction 5.7%, and pure indirect effect 4.4%). Adult SES accounted for 10.1% (via mediation) and 26.5% (via exposure-mediator interaction) of the total association between ACEs and depressive symptoms, respectively. CONCLUSION: ACEs appeared to be a strong and independent determinant of depressive symptoms in later life. Nonetheless, the interaction between ACEs and adult SES indicates that achieving high adult SES could mitigate the adverse effect of ACEs on late-life depression.

PURPOSE: This study investigates the contextual association between types of community-level social participation and functional disability. METHODS: We used 6-year prospective cohort data from the Japan Gerontological Evaluation Study 2010-2016, a nationwide survey of 35,519 functionally independent older adults (mean age: 73.30 ± 5.91 years, 49.6% females). The incidence of functional disability was obtained from municipal long-term care insurance databases. Social participation was assessed at individual and community levels and was categorized as: volunteer, sports, hobby and neighborhood groups, and senior citizen clubs. We calculated the 95% confidence interval (CI) and the hazard ratio (HR) by applying a three-level multilevel survival analysis. RESULTS: During the 6-year observation period, the onset of functional disability occurred among 3473 adults. A higher prevalence of sports (HR 0.88, 95% CI 0.80 to 0.96) and hobby group participation (HR 0.91, 95% CI 0.87 to 0.96) showed significant contextual relationships with functional disability after adjusting for potential confounders. Among females, community-level neighborhood group participation significantly lowered the incidence of functional disability (HR 0.87, 95% CI 0.76 to 0.998). CONCLUSIONS: We found a beneficial effect of a contextual relationship between community-level sports and hobby group participation and functional disability among older adults. Moreover, females benefited a lot from community-level social participation. We propose that promoting sports and hobby groups in a community may help to prevent functional disability among older adults.

BACKGROUND: Women have been observed to have a higher risk of developing posttraumatic stress symptoms (PTSS) after disaster compared to men. In a study of survivors of an earthquake, we sought to investigate: whether there was differential exposure to disaster-related trauma by gender; whether women and men have differential vulnerability to trauma; and what factors could explain the gender difference in PTSS. METHODS: Data from a cohort of community-dwelling older survivors of the 2011 Great East Japan Earthquake and Tsunami was used. Data were obtained before (2010) and 2.5-years after the disaster (n = 3,334). RESULTS: Women suffered 1.6 times higher prevalence of PTSS than men (31.0% vs. 19.4%). Women were more likely to experience loss of relatives (29.2% vs. 23.2%), while men were more likely to report loss of friends (17.1% vs. 14.5%) and separation from work (7.5% vs. 4.6%). We did not find evidence for differential vulnerability to disaster-related trauma. Indeed, the gender gap in PTSS was larger among individuals who did not experience trauma. Women experienced greater deterioration of non-kin instrumental support, which significantly mediated the association between gender and PTSS. LIMITATIONS: We have no information on PTSS prior to the earthquake. Nor do we have clinician diagnoses of PTSD. CONCLUSIONS: Women experienced housing damages and loss of relatives more often than men, which explained ∼21% of the gender gap in PTSS after disaster. Women reported more non-kin support prior to the disaster, but they also experienced greater deterioration of it, which explained ∼21% of the gender gap.

Relative income deprivation (RID) is a known risk factor for poor health. Previous research has proposed several measures to assess RID, e.g., Income Rank and the Yitzhaki Index. Hounkpatin et al. (2020) presented a new approach - the CR˜i index - to account for the observation that individuals are more sensitive to the differences in incomes of others who are closer to them, rather than to comparisons with incomes of others far above them. Using a Japanese nationwide cohort of older adults (n = 62,438; mean [SD] age: 73.0 [5.6] years), this study compared the performance of alternative indices of RID in predicting health outcomes (depressive symptoms, functional capacity, and self-rated health), as well as the use of alternative CR˜i index weights (α weight range: -0.9 to 0.9). When 0<α<1, higher income differences lead to a more significant increase in relative deprivation, while when -1< α <0, excessively high incomes contribute less to the relative deprivation of lower income individuals in the same reference group. Results showed that all measures of relative income deprivation were associated with deteriorating mental and physical health among older Japanese adults. However, while the CR˜i index consistently outperformed the Yitzhaki Index, this did not hold true invariably when compared to the Income Rank - depending on the health outcome and the reference group. Also, while negative α parameters showed a good statistical fit in most models, the findings were not conclusive - the best-fitting CR˜i weight parameters ranged from -0.9 to 0.9. Therefore, a clear direction for the contribution of higher incomes to relative deprivation could not be established based on the study population.

目的 高齢者の歩行量を維持・増加させることには多くの健康上望ましい効果が期待できる。しかし，健康日本21（第二次）中間評価では，高齢者の歩数が目標値まで達成できなかったことが報告されている。そのため，従来とは異なるアプローチに建造環境（街路ネットワーク，施設や居住密度，土地利用など人工的に造られる環境）を通じた身体活動量や歩数の維持・増加をもたらすゼロ次予防が注目されている。本研究では，建造環境の1つである生鮮食料品店の変化と歩行時間の変化との関連を明らかにすることを目的とした。 方法 日本老年学的評価研究（JAGES）が27市町の要介護認定を受けていない65歳以上を対象に実施した自記式郵送調査データを用いた2016・2019年度の2時点での縦断パネル研究である。目的変数は，歩行時間の2時点の変化（増加あり・なし）とし，説明変数は追跡前後の徒歩圏内にある生鮮食料品（肉，魚，野菜，果物など）が手に入る生鮮食料品店の有無の2時点の変化を5群にカテゴリー化（なし・なし：参照群，なしとわからない・あり，あり・あり，あり・なしとわからない，その他）したものである。調整変数は2016年度の人口統計学的要因，健康行動要因，環境要因，健康要因の計14変数とした。統計分析は，ロバスト標準誤差を用いたポアソン回帰分析（有意水準5％）で歩行時間の増加なしに対する歩行時間の増加ありとなる累積発生率比（cumulative incidence rate ratio：CIRR）と95％信頼区間（confidence interval：CI）を算出した。分析に使用する全数のうち，無回答者などを欠測として多重代入法で補完した。 結果 歩行時間の増加ありが13,400人（20.4％）だった。追跡前後で徒歩圏内の生鮮食料品店の有無の変化が「なし・なし」（6,577人，10.0％）と比較した場合，「なしとわからない・あり」（5,311人，8.1％）のCIRRは1.12（95％CI：1.03-1.21）だった。 結論 徒歩圏内の生鮮食料品店が増加していた者で，高齢者の歩行時間が増加した者の発生が12％多かった。暮らしているだけで歩行量が増える建造環境の社会実装を目指す手がかりを得られたと考える。

Objectives: Disasters change survivors' living circumstances, which can affect their happiness. We examined the trends in the association between disaster damage and happiness before and after a disaster. Methods: We analyzed 4,044 participants aged ≥65 years who had experienced the Great East Japan Earthquake in 2011. The baseline survey was conducted 7 months before the disaster. Follow-up surveys have been conducted every 3 years. Using a mixed model for repeated measures, we compared the prevalence ratios (PRs) for unhappiness according to the survivors' level of housing damage, which is a proxy for disaster damage. Results: The unhappiness in participants who suffered severe damage appeared to be higher than in those with no damage in 2010 (multivariate-adjusted PR: 1.18, 95% confidence interval: 0.93-1.48). A higher PR was observed after the earthquake in 2013 (1.34, 0.79-2.28), while there was no difference in 2016 (1.02, 0.53-1.97) and 2019 (1.03, 0.50-2.12). Conclusion: The prevalence of unhappiness in survivors with severe housing damage was higher before the disaster. However, the unhappiness gap between people with and without housing damage converged during the follow-up.

Tooth loss is a risk factor for increased mortality; however, the underlying mechanism remains unclear. This study aimed to evaluate the mediating effect of weight change on the relationship between tooth loss and mortality risk. This was a 10-y follow-up prospective cohort study using the data from the Japan Gerontological Evaluation Study (JAGES). The participants were independent older adults aged ≥65 y at baseline and were followed up from 2010 to 2020. The incidence of death in 2013 and 2020, incidence of >5% weight loss/gain in 2010 and 2013, and the number of remaining teeth in 2010 were used as the outcome, mediator, and explanatory variables, respectively. We conducted causal mediation analysis by fitting the Cox proportional hazard model, including possible confounders. Hazard ratios (HRs) and 95% confidence intervals (95% CIs) of the total effect (TE), natural indirect effect (NIE), and proportion mediated (PM) were estimated. Among the 34,510 participants, the mean age was 72.6 (SD = 5.4) y, and 47.6% were men. From 2013 to 2020, 14.0% of the participants (n = 4,825) died, 60.5% (n = 20,871) had 0 to 19 remaining teeth, and 17.2% (n = 5,927) and 8.4% (n = 2,907) experienced >5% weight loss and gain, respectively. The mortality rate was 0.016 per person-year among those with ≥20 remaining teeth and 0.027 per person-year among those with 0 to 19 remaining teeth. Weight loss of >5% significantly mediated the association between tooth loss and higher mortality risk (TE: HR, 1.28 [95% CI, 1.16 to 1.40]; NIE: HR, 1.03 [95% CI, 1.02 to 1.04]; PM, 13.1%); however, we observed a slight mediating effect for >5% weight gain (NIE: HR, 1.003 [95%CI, 1.0001 to 1.01]; PM, 1.3%). The present study suggests that a clinically meaningful level of weight loss mediated the association between tooth loss and increased risk of mortality among independent older adults.

目的:高齢者の運動習慣定着に有効な運動プログラムのあり方を検討するために,民間スポーツクラブを利用する高齢者を対象にグループでの運動の実践と運動の継続との関連を明らかにすることを目的とした.方法:2017年6月から2019年3月にかけてリソルの森の健康増進プログラム(ウェルネスエイジクラブ)に6ヵ月以上参加した65歳以上の227人(女性117人,男性110人)を分析対象とした.半年に1回の質問紙調査,体力測定,年1回の健康診断,及び個人の参加プログラムや参加日時のデータを分析に用いた.24週以上に渡る平均週2日以上の運動プログラム参加を「運動プログラム継続」,平均週1回以上のグループプログラムへの参加を「グループプログラム参加」と定義し,グループプログラム参加と運動プログラム継続との関連をポアソン回帰分析により検証した.結果:グループプログラム参加者は,非参加者に比べて運動プログラムを継続する可能性が高かった(Prevalence ratio=3.63[95%CI:1.98〜6.65],p<0.01).性で層化しても,女性(8.08[1.94〜33.56],p<0.01),男性(2.84[1.39〜5.78],p<0.01)ともにグループプログラム参加と運動プログラム継続に有意な正の関連が認められた.結論:本研究は,民間スポーツクラブに通う高齢者において,グループによる運動プログラムは参加者同士の社会的交流やつながりを増やし運動継続を促進する可能性があることを明らかにした.高齢者のグループ運動への参加を促進することで運動継続者が増加する可能性が示唆された.(著者抄録)

Aim: We investigated the association between subjective cognitive complaints (SCCs) and dental visits in older Japanese adults. Methods: This was a cross-sectional study from the Japan Gerontological Evaluation Study (carried out in 2019). The participants were independent older adults aged ≥65 years without dementia. The presence/absence of dental treatment visits and dental checkup visits within the past 12 months were used as outcome variables. The SCC score measured using the Kihon Checklist was set as the explanatory variable. Possible confounders were also included as covariates. Prevalence ratios and 95% confidence intervals were estimated using a Poisson regression model. Results: The mean age was 74.1 years (standard deviation 6.0 years). Among the 19 677 eligible participants, 12 359 (62.8%) had dental treatment visits and 11 063 (56.3%) had dental checkup visits. Of these, 5966 (30.3%) had an SCC score of ≥1. The proportion of participants with dental treatment and dental checkup visits within the past 12 months was 63.2% and 56.7% among those with SCC score = 0, and 52.8% and 35.2% among those with SCC score = 3, respectively. In the fully adjusted model, no significant association was observed for participants with SCC scores of 1 and 2. Those with SCC score = 3 had less frequent dental checkup visits (prevalence ratio 0.74, 95% confidence interval 0.57–0.95). Conclusions: Our study highlights that SCC was not associated with limited access to dental care among those with mild SCC. However, those with the highest SCC score seemed to have disturbed access to dental care. Geriatr Gerontol Int 2022; ••: ••–••.

Evidence on the association between internet usage and incidence of depression remains mixed. We examined the associations between different categories of internet usage and developing clinical depression. We used data from the 2013 and 2016 waves of the Japan Gerontological Evaluation Study (JAGES) comprising 12,333 physically and cognitively independent adults aged ≥65 years. Participants were engaged in seven categories of internet usage: communication with friends/family, social media, information collection about health/medicine, searching for medical facilities, purchase of drugs and vitamins, shopping, and banking. We found that internet use for communication had a protective influence on the probability of developing clinical depression defined as the Geriatric Depression Scale scores ≥5 or self-reported diagnosed depression. Our findings support the role of online communication with friends/family in preventing clinical depression among older people. Online communication could be particularly useful in the COVID-19 crisis because many families are geographically dispersed and/or socially distanced.