Pneumococcal vaccination, but not influenza vaccination, is negatively associated with incident dementia among Japanese older adults: The JAGES 2013-2022 prospective cohort study.

BACKGROUND: It is unclear whether inactivated influenza vaccination (IIV) or pneumococcal vaccination are associated with the risk of dementia; however, both types of vaccination are recommended for older adults. Studies have shown that the IIV is negatively associated with incident dementia; however, the uptake of pneumococcal vaccinations has not been considered. We investigated the independent associations of IIV and 23-valent pneumococcal polysaccharide vaccine (PPSV23) with incident dementia in older adults. METHODS: Health-related information on older Japanese adults was obtained through a baseline survey conducted in 2013 (baseline survey). The uptake of IIV and PPSV23 was determined in a second survey conducted in 2016 (second wave). Both surveys were conducted among independent Japanese older adults aged ≥ 65 years at the two surveys and who had not been certified as needing long-term care (LTC). In the second wave, 9,865 participants were followed up for 3.5 years (short-term follow-up), and 6,995 participants were followed up for six years and five months (long-term follow-up) until they required LTC due to dementia onset (incident dementia). A competing risk model with stabilized inverse probability weighting (SIPW) was constructed to calculate the hazard ratios (HRs) and 95 % confidence intervals (CIs) of incident dementia. RESULTS: PPSV23 uptake was negatively associated with incident dementia among participants in both the short- and long-term follow-up periods after SIPW (short-term follow-up: HR: 0.77, 95 % CI: 0.63 - 0.95; long-term follow-up: HR: 0.83, 95 % CI: 0.70 - 0.97). Conversely, IIV uptake was not associated with incident dementia among participants in either follow-up group (short-term follow-up: HR: 0.86, 95 % CI: 0.63-1.16; long-term follow-up: HR: 0.99, 95 % CI: 0.76-1.29). The PPSV23 uptake was negatively associated with incident dementia in participants without the IIV uptake (short-term follow-up: HR: 0.44, 95 % CI: 0.24 - 0.81; long-term follow-up: HR: 0.47, 95 % CI: 0.29 - 0.76). Conversely, the IIV uptake was not associated with incident dementia regardless of the PPSV23 status (short-term follow-up: HR: 0.87, 95 % CI: 0.62 - 1.23; long-term follow-up: HR: 1.00, 95 % CI: 0.74 - 1.35). CONCLUSION: Our results suggest that the PPSV23 uptake was independently associated with the incidence of dementia. However, the IIV uptake was not associated with the incidence of dementia.

Association of frailty with influenza and hospitalization due to influenza among independent older adults: a longitudinal study of Japan Gerontological Evaluation Study (JAGES).

BACKGROUND: It is unknown that whether frailty is a risk factor of influenza and the hospitalization among older adults, although it has been shown that frailty was associated with poor recovery from the hospitalization among those. We examined the association of frailty with influenza and the hospitalization and the effect by sex among independent older adults. METHODS: We used the longitudinal data from the Japan Gerontological Evaluation Study (JAGES), performed in 2016 and 2019 and conducted in 28 municipalities in Japan. The target population comprised 77,103 persons aged ≥ 65 years who did not need assistance from the public long-term care insurance. Primary outcome measures were influenza and hospitalization due to influenza. Frailty was evaluated with the Kihon check list. We estimated the risk of influenza, the hospitalization, those risks by sex, and the interaction for frailty and sex using Poisson regression adjusting for covariates. RESULTS: Frailty was associated with both influenza and the hospitalization among the older adults compared with nonfrail individuals after adjusting for covariates (influenza, frail: risk ratio {RR}: 1.36, 95% confidence interval {95% CI}: 1.20 - 1.53, and prefrail: RR: 1.16, 95% CI: 1.09 - 1.23; the hospitalization, frail: RR: 3.18, 95% CI: 1.84 - 5.57, and prefrail: RR: 2.13, 95% CI: 1.44 - 3.16). Male was associated with the hospitalization, but not associated with influenza compared to female (the hospitalization: RR: 1.70, 95% CI: 1.15 - 2.52 and influenza: RR: 1.01, 95% CI: 0.95 - 1.08). The interaction for frailty and sex was significant neither in influenza nor in the hospitalization. CONCLUSION: These results suggest that frailty is a risk of influenza and the hospitalization, that risks of the hospitalization are different by sex, but that the sex difference does not cause the effect heterogeneity of frailty on the susceptibility and severity among independent older adults.

Associations of influenza and pneumococcal vaccinations with burdens of older family caregivers: The Japan Gerontological Evaluation study (JAGES) cross-sectional study.

BACKGROUND: Influenza and pneumonia tend to be severe in older adults; thus, vaccination is necessary to prevent these illnesses. Vaccination is especially important for older family caregivers (OFCs) not only to prevent them from becoming ill, but also to prevent secondary infections in the family care receivers (FCRs), who are mostly frail older adults and have a higher risk of severe illness. Thus, we investigated whether caregiving burdens were associated with the vaccinations among older adults. METHODS: We used cross-sectional data from the Japan Gerontological Evaluation Study (JAGES), which was conducted in 64 Japanese municipalities from November 2019 to January 2020. The target population consisted of 26,177 individuals aged 65 years or older who were independent and did not need public long-term care. The primary outcome was the uptakes of either or both influenza and pneumococcal vaccinations. Multinomial logistic regressions were performed, setting those who underwent neither vaccinations as the reference group. RESULTS: Among the participants, 23.3 %, 25.8 %, 9.4 %, or 41.5 % underwent neither, only influenza, only pneumococcal, or the both vaccinations, respectively. The caregiving frequency, time length in a day, or dementia of FCR were negatively associated with influenza vaccination (caregiving almost every day: relative risk ratio {RRR}: 0.39, 95 % confident interval {95 % CI} [0.24-0.63]; caregiving almost all day: 0.44, 95 % CI: 0.23-0.85; caregiving for FCR: RRR:0.55, 95 % CI: 0.34-0.91). On the other hand, those caregiving burdens were not associated with pneumococcal only or the both vaccinations. Having a family physician mitigated all the negative effect of the caregiving burdens on the vaccinations. CONCLUSION: Our results suggest that the caregiving burden is a barrier to influenza vaccination but not to pneumococcal vaccination and that having a physician mitigates the negative effect regardless of the burden kind.

Association of functional competencies with vaccination among older adults: a JAGES cross-sectional study.

It is unknown whether higher functions in sublevels of competence other than instrumental activities of daily living (IADL) are associated with vaccinations. This study examined whether higher functions, including intellectual activity (IA) and social role (SR), were associated with vaccinations among 26,177 older adults. Older adults with incapable activities in IA and SR had increased risks for non-receipt of influenza vaccinations (IA: for one incapable task/activity: incident rate ratio (IRR) = 1.05, 95% confidence interval (CI) = 1.02-1.09; SR: for two incapable tasks: IRR = 1.12, 95% CI = 1.08-1.16). Those with incapable activities in IADL and IA had increased risks for non-receipt of pneumococcal vaccination (IADL: for two incapable tasks: IRR = 1.13, 95% CI = 1.05-1.23; IA: for two incapable tasks: IRR = 1.10, 95% CI = 1.08-1.12). Those with incapable activities in IADL, IA, and SR had increased risks for non-receipt of both of the two vaccinations (IADL: for two incapable tasks: IRR = 1.17, 95% CI = 1.03-1.33; IA: for two incapable tasks: IRR = 1.18, 95% CI = 1.11-1.25; SR: for two incapable tasks: IRR = 1.13, 95% CI = 1.07-1.20). Having a family physician mitigated associations for non-receipt, regardless of competency. Our results suggest-maintaining the higher functions are important for older adults to undergo recommended vaccinations as scheduled; also, having a family physician to promote vaccinations is beneficial even for older adults with limited functions.

Social capital and pneumococcal vaccination (PPSV23) in community-dwelling older Japanese: a JAGES multilevel cross-sectional study.

OBJECTIVE: Inequalities exist between the 23-valent pneumococcal polysaccharide vaccination (PPSV23) rate in each municipality among Japanese older adults. Exploring individual-level and community-level intervenable factors is necessary to improve the vaccination rates. We examined the associations between community-level and individual-level social capital and the PPSV23 vaccination among older Japanese adults using multilevel Poisson regression analyses. DESIGN: Cross-sectional study. SETTING: We used data from the Japan Gerontological Evaluation Study, conducted between 3 October 2016 and 10 January 2017 in 631 districts, 39 municipalities and 18 prefectures. PARTICIPANTS: The target population comprised persons aged 65 years or older who are physically and cognitively independent (that is, not certified as needing long-term care). Further, 180 021 older adults from 39 Japanese municipalities were enrolled. PRIMARY OUTCOME MEASURE: The primary outcome was the PPSV23 vaccination among the Japanese older adults aged 65 years or older who did not have physical or cognitive disabilities. RESULTS: After adjusting for municipality-, community-, individual-levels effects with multiple imputation, 137 075 individuals who participated in one/more of the civic participation (participation of social groups), social cohesion (social tie), or reciprocity (mutual exchange of social support) were significantly associated with more vaccinations than those without the three social capitals among the 137 075 older adults (13.0% (95% CI 11.0% to 14.9%), 5.0% (95% CI 2.4% to 7.6%) or 33.9% (95% CI23.6% to 44.2%) increase, respectively, p>0.001 for all). The rich (≥+1 SD) community-level civic participation was significantly associated with 3.4% increase [95% CI 0.02% to 6.78%, p<0.05] of the PPSV23 vaccination among the older adults compared to those with the poor or standard one. CONCLUSIONS: Older adults with one/more of the three social capitals at the both levels received more PPSV23 vaccinations than those without those social capitals. Therefore, fostering of those social capitals may improve the inequality of the PPSV23 vaccination rate among older adults in each municipality.

Frailty is associated with susceptibility and severity of pneumonia in older adults (A JAGES multilevel cross-sectional study).

Pneumonia is a leading cause of mortality among older adults worldwide. Recently, several studies reported that frailty was associated with mortality among older adults hospitalized due to respiratory infectious diseases, including pneumonia. However, it is unknown whether frailty is associated with susceptibility to and severity of pneumonia in functionally-independent community-dwelling older adults. In this study, we examined whether frailty increased the susceptibility to pneumonia and hospitalization in older adults. We used cross-sectional data from the Japan Gerontological Evaluation Study; the data was collected by using mail-based, self-reported questionnaires from 177,991 functionally-independent community-dwelling older adults aged ≥ 65 years. Our results showed that frailty was significantly associated with both occurrence of and hospitalization due to pneumonia after adjustments with covariates; (Preference ratio {PR} 1.92, 95% confidence interval {95% CI} [1.66-2.22] and PR 1.80, 95% CI [1.42-2.28], respectively, p < 0.001 for the both). Pre-frailty was associated only with the occurrence of pneumonia. Besides, the instrumental activity of daily living, physical strength, nutrition status, oral function, homeboundness, and depression status in frail older adults were associated with either or both occurrence of and hospitalization due to pneumonia. Our results suggest that frailty influenced the susceptibility to and severity of pneumonia in older adults.