Association between social participation and disability-free life expectancy in Japanese older people: the Ohsaki Cohort 2006 Study

Association between education and disability-free life expectancy among Japanese older people: The Ohsaki Cohort 2006 study

BACKGROUND

Higher education level is associated with longer disability-free life expectancy (DFLE). However, evidence is scarce regarding factors that can contribute to eliminating inequality in DFLE according to education level. This study aimed to clarify the association between education and DFLE and estimate whether DFLE in people with lower education may increase to the same level as that in people with higher education through social participation.

METHODS

We analyzed data from 13,849 Japanese people aged 65 years and older who participated in a 13-year prospective study. At baseline, we collected information on education levels (low, middle, or high) and social participation. DFLE was defined as the average duration people expect to live without disability. To calculate DFLE for each education level group, the multistate life table method was employed using a Markov model.

RESULTS

At the age of 65 years, DFLE (95 % confidence interval [CI]) in women with low education was 21.3 years (20.8-21.8) without social participation and 24.3 (23.8-24.9) with social participation. In the middle education group, DFLE was 22.1 (21.6-22.6) without social participation and 25.0 (24.6-25.5) with social participation. In the high education group, DFLE was 22.1 (21.5-22.8) without social participation and 25.5 (25.0-26.0) with social participation. Similar results were found for men.

CONCLUSIONS

DFLE in people with low or middle education with social participation was almost the same as that in those with high education with social participation, suggesting the possibility that disparities in DFLE by education level could be offset by promoting social participation in older adults.

Life expectancy and years of potential life lost in people with mental disorders: a systematic review and meta-analysis

Background

Mental disorders are associated with premature mortality. There is increasing research examining life expectancy and years-of-potential-life-lost (YPLL) to quantify the disease impact on survival in people with mental disorders. We aimed to systematically synthesize studies to estimate life expectancy and YPLL in people with any and specific mental disorders across a broad spectrum of diagnoses.

Methods

In this systematic review and meta-analysis, we searched Embase, MEDLINE, PsychINFO, WOS from inception to July 31, 2023, for published studies reporting life expectancy and/or YPLL for mental disorders. Criteria for study inclusion were: patients of all ages with any mental disorders; reported data on life expectancy and/or YPLL of a mental-disorder cohort relative to the general population or a comparison group without mental disorders; and cohort studies. We excluded non-cohort studies, publications containing non-peer-reviewed data or those restricted to population subgroups. Survival estimates, i.e., life expectancy and YPLL, were pooled (based on summary data extracted from the included studies) using random-effects models. Subgroup analyses and random-effects meta-regression analyses were performed to explore sources of heterogeneity. Risk-of-bias assessment was evaluated using the Newcastle-Ottawa Scale. This study is registered with PROSPERO (CRD42022321190).

Findings

Of 35,865 studies identified in our research, 109 studies from 24 countries or regions including 12,171,909 patients with mental disorders were eligible for analysis (54 for life expectancy and 109 for YPLL). Pooled life expectancy for mental disorders was 63.85 years (95% CI 62.63-65.06; I2 = 100.0%), and pooled YPLL was 14.66 years (95% CI 13.88-15.98; I2 = 100.0%). Disorder-stratified analyses revealed that substance-use disorders had the shortest life expectancy (57.07 years [95% CI 54.47-59.67]), while neurotic disorders had the longest lifespan (69.51 years [95% CI 67.26-71.76]). Substance-use disorders exhibited the greatest YPLL (20.38 years [95% CI 18.65-22.11]), followed by eating disorders (16.64 years [95% CI 7.45-25.82]), schizophrenia-spectrum disorders (15.37 years [95% CI 14.18-16.55]), and personality disorders (15.35 years [95% CI 12.80-17.89]). YPLLs attributable to natural and unnatural deaths in mental disorders were 4.38 years (95% CI 3.15-5.61) and 8.11 years (95% CI 6.10-10.13; suicide: 8.31 years [95% CI 6.43-10.19]), respectively. Stratified analyses by study period suggested that the longevity gap persisted over time. Significant cross-study heterogeneity was observed.

Interpretation

Mental disorders are associated with substantially reduced life expectancy, which is transdiagnostic in nature, encompassing a wide range of diagnoses. Implementation of comprehensive and multilevel intervention approaches is urgently needed to rectify lifespan inequalities for people with mental disorders.

Funding

None.

Effect of social participation on the association between frailty and disability

OBJECTIVES

To examine whether social participation affects the association between frailty and disability.

METHODS

A baseline survey conducted from December 1 to 15, 2006, included 11,992 participants who were classified based on the Kihon Checklist into three categories and based on the number of activities in which they socially participated into four categories. The study outcome, incident functional disability, was defined as in Long-Term Care Insurance certification. A Cox proportional hazards model was used to calculate hazard ratios (HRs) for incident functional disability according to frailty and social participation categories. Combination analysis was performed between the nine groups using the above-mentioned Cox proportional hazards model.

RESULTS

During the 13-year follow-up (107,170 person-years), 5,732 incident cases of functional disability were certified. Compared with the robust group, the other groups had significantly higher incident functional disability. However, the HRs for those participating in social activities were lower than that for those not participating in any activity [1.52 (pre-frail + none group); 1.31 (pre-frail + one activity group); 1.42 (pre-frail + two activities group); 1.37 (pre-frail + three activities group); 2.35 (frail + none group); 1.87 (frail + one activity group); 1.85 (frail + two activities group); and 1.71 (frail + three activities group)].

CONCLUSIONS

The risk of functional disability for those participating in social activities was lower than that for those not participating in any activity, irrespective of being pre-frail or frail. Comprehensive social systems for disability prevention need to focus on social participation in frail older adults.

Association between the number of remaining teeth and disability-free life expectancy, and the impact of oral self-care in older Japanese adults: a prospective cohort study

Background

Tooth loss has been reportedly associated with shorter disability-free life expectancy (DFLE). However, no study has explored whether oral self-care offsets reduction in DFLE. The present study aimed to assess the association between oral self-care and DFLE in older individuals with tooth loss.

Methods

Data on the 13-year follow-up from a cohort study of 14,206 older Japanese adults aged ≥ 65 years in 2006 were analyzed. Information on the number of remaining teeth was collected using a questionnaire, and the participants were then categorized into three groups (0–9, 10–19, and ≥ 20 teeth). Additionally, “0–9” and “10–19” groups were divided into two subgroups based on whether they practiced oral self-care. DFLE was defined as the average number of years a person could expect to live without disability, and was calculated by the multistate life table method based on a Markov model.

Results

DFLE (95% confidence interval) was 19.0 years (18.7–19.4) for 0–9 teeth, 20.1 (19.7–20.5) for 10–19 teeth, and 21.6 (21.2–21.9) for ≥ 20 teeth for men. For women, DFLE was 22.6 (22.3–22.9), 23.5 (23.1–23.8), and 24.7 (24.3–25.1), respectively. Practicing oral self-care was associated with longer DFLE, by 1.6–1.9 years with brushing ≥ 2 times a day in people with 0–9 and 10–19 teeth, and by 3.0–3.1 years with the use of dentures in those with 0–9 teeth.

Conclusions

Practicing oral self-care is associated with an increase in DFLE in older people with tooth loss.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12877-022-03541-2.

Less Social Participation Is Associated With a Higher Risk of Depressive Symptoms Among Chinese Older Adults: A Community-Based Longitudinal Prospective Cohort Study

OBJECTIVE

We aimed to examine the association between social participation and depressive symptoms among Chinese older people aged 65 years or above to supplement limited studies in China on this topic.

METHODS

This community-based longitudinal prospective cohort study used the data from the Chinese Longitudinal Healthy Longevity Survey (CLHLS, baseline in 2014 and a follow-up in 2018). Depressive symptoms were assessed using the 10-item Center for Epidemiologic Studies Depression Scale. Social participation was assessed using a composite index by considering the frequency for the two types of social activity: organized social activities and informal activities. Pearson's χ² test was used to correlate the characteristics of participants with social participation or depressive symptoms. Log-binomial regression models were used to assess the association between social participation and the risk of depressive symptoms.

RESULTS

The incidence of depressive symptoms was 28.8% among 2,200 participants in 2018 after a 4-year follow-up. Participants with no social participation (32.6%), organized social activities (30.6%), or informal social activities (31.2%) were more likely to have depressive symptoms. After the adjustment of demographic factors, socioeconomic status, lifestyle habits, and health status, in comparison with older people who often engaged in social participation, organized social activities, and informal social activities, the risk of depressive symptoms was 45% [adjusted risk ratio (aRR): 1.45, 95% CI: 1.16-1.82], 42% (aRR: 1.45, 95% CI: 1.02-2.00), and 29% (aRR: 1.29, 95% CI: 1.02-1.99) higher among older people with no social participation and who never engaged in organized social activities and informal social activities, respectively.

CONCLUSIONS

This study showed that the lack of social participation, including organized social activities and informal social activities, was associated with a higher risk of depressive symptoms after 4 years among older adults in China. Our findings shed lights into the feasibility of promoting social participation to reduce the risk of depressive symptoms and promote longevity and healthy aging among older adults.