Association of the combination of social isolation and living alone with cognitive impairment in community-dwelling older adults: The IRIDE Cohort Study.

BACKGROUND: Living alone has been associated with cognitive impairment; however, findings have been inconsistent. Social isolation among older adults who live alone may contribute to cognitive impairment. This study was carried out to examine the association of social isolation and living alone with cognitive impairment in community-dwelling older adults. METHODS: In this cross-sectional study, data from the Integrated Research Initiative for Living Well with Dementia Cohort Study, which comprises pooled data from five community-based geriatric cohorts, was used. Social isolation was defined as infrequent interactions with others. Participants were categorized into four groups based on their social isolation and living alone statuses. Cognitive function was assessed using the Mini-Mental State Examination, with a score <24 indicating cognitive impairment. The association between social isolation combined with living alone and cognitive impairment was analyzed using logistic regression. RESULTS: Of the 4362 participants included in the analysis (mean age 75.6 years, 44.3 % male), 11 % had cognitive impairment. Regardless of living alone, social isolation was associated with cognitive impairment (no social isolation x not living alone: reference, social isolation x not living alone; odds ratio (OR): 1.74, 95 % confidence interval (CI): 1.29-2.33, social isolation x living alone; OR: 2.10, 95 % CI: 1.46-3.01). CONCLUSIONS: Social isolation is associated with cognitive impairment; however, living alone is not intrinsically associated with cognitive impairment in older adults. Healthcare providers must focus on social interactions to prevent cognitive impairment in older adults rather than simply focusing on living arrangements.

Serum albumin redox state as an indicator of dietary protein intake among community-dwelling older adults.

BACKGROUND AND AIMS: Serum markers capable of detecting mild levels of undernutrition, such as insufficient dietary protein intake (IDPI), have not been established among community-dwelling older adults. Although the serum albumin redox state, expressed as the ratio of reduced albumin (Alb) to total Alb (the reduced albumin ratio), has the potential to overcome this challenge, empirical epidemiological data are lacking. This study aimed to investigate the association between a serum reduced Alb ratio and dietary protein intake among community-dwelling older adults. METHODS: This study analyzed cross-sectional data from 1,005 community dwelling population (572 males and 433 females) aged 70-84 years who participated in the Itabashi Longitudinal Study on Aging. Exclusion criteria included participants with incomplete data, individuals with a history of kidney disease and high C-reactive protein (CRP) levels. The dietary protein intake was estimated using validated food frequency questionnaires. The IDPI was defined as not meeting the level recommended by the Dietary Reference Intakes for Japanese (Men ≥60 g/day, Women ≥50 g/day). RESULTS: IDPI was observed in 14.1% of the study population. Logistic regression analyses adjusted for sex, age, body weight and malnutrition showed that a serum reduced Alb ratio was significantly associated with IDPI (odds ratio = 0.962, 95% confidence interval = 0.926-0.999), whereas serum albumin concentration was not (odds ratio = 0.549, 95% confidence interval = 0.285-1.061). CONCLUSIONS: A serum reduced Alb ratio would be a useful indicator of protein insufficiency among community-dwelling older adults.

Corrigendum: Sex-specific factors associated with acceptance of smartwatches among urban older adults: the Itabashi longitudinal study on aging.

[This corrects the article DOI: 10.3389/fpubh.2024.1261275.].

DASC-21 score and the risk of in-hospital death in elderly patients with heart failure.

AIM: We investigated whether the Dementia Assessment Sheet for Community-based Integrated Care System-21 Items (DASC-21), a questionnaire that assesses cognitive function, including activities of daily living (ADL), was predictive of in-hospital death and prolonged hospital stay in elderly patients hospitalized for heart failure. METHODS: We retrospectively assessed the DASC-21 score at the time of admission, in-hospital death, length of hospital stay, and change in the Barthel index in 399 patients hospitalized for heart failure between 2016 and 2019. RESULTS: The mean patient age was 85.8 ± 7.7 years (61.3% women). The median DASC-21 score was 38 (64.7% higher than 31). On multivariate logistic regression analysis, a higher DASC-21 score was associated with an increased risk of in-hospital death (odds ratio [OR] = 1.045 per 1 point increase, 95% confidence interval [CI]: 1.010-1.081, P = 0.012), even after adjusting for confounding factors, including atrial fibrillation, ejection fraction, and B-type natriuretic peptide. Difficulties (3 or 4) with the self-management of medication in instrumental ADL inside the home (OR = 3.28, 95% CI: 1.05-10.28, P = 0.042), toileting (OR = 3.66, 95% CI: 1.19-11.29, P = 0.024), grooming (OR = 6.47, 95% CI: 2.00-20.96, P = 0.002), eating (OR = 7.96, 95% CI: 2.49-25.45, P < 0.001), and mobility in physical ADL (OR = 5.99, 95% CI: 1.85-19.35, P = 0.003) were identified as risk factors for in-hospital death. Patients in the highest tertile of the DASC-21 score had a significantly longer hospital stay (P = 0.006) and a greater reduction in the Barthel index (P < 0.001). CONCLUSIONS: In elderly patients hospitalized for heart failure, higher DASC-21 scores were associated with an increased risk of in-hospital death, prolonged hospital stay, and impaired ADL. Geriatr Gerontol Int 2024; 24: 546-553.

Proposal and validation of an equation to identify sarcopenia using bioelectrical impedance analysis-derived parameters.

OBJECTIVE: This study aimed to develop a simpler approach for diagnosing sarcopenia by using only bioelectrical impedance vector analysis parameters. METHODS: The study design was a cross-sectional study. The research was conducted based on the Itabashi Longitudinal Study on Aging, a community-based cohort study, with data collected from the 2022 and 2023 surveys in Itabashi Ward, Tokyo, Japan. The development cohort consisted of 1146 participants from the 2022 survey, and the validation cohort included 656 participants from the 2023 survey. Both cohorts were comprised of community-dwelling older adults with similar inclusion criteria. Sarcopenia was defined according to the Asian Working Group for Sarcopenia 2019 criteria. The logistic model utilized height divided by impedance at 50 kHz and phase angle to establish a new regression equation to identify sarcopenia. Regression equations were generated for the development cohort and validated for the validation cohort. Discriminatory ability was assessed using the area under the receiver operating characteristic curve (AUC) for men and women. RESULTS: The prevalence of sarcopenia was 20.7% and 14.8% in the development and validation cohort, respectively. The AUC (95% confidence interval) of the logistic model in discriminating sarcopenia was 0.92 (0.88, 0.95) for men and 0.82 (0.78, 0.86) for women in the development cohort and 0.85 (0.78, 0.91) for men and 0.90 (0.86, 0.95) for women in the validation cohort. CONCLUSION: The study demonstrated that a simple formula using bioelectrical parameters at 50 kHz proved useful in identifying sarcopenia in the older adult population.

Sex-specific factors associated with acceptance of smartwatches among urban older adults: the Itabashi longitudinal study on aging.

Smartwatches (SW) are wearable devices that support daily life and monitor an individual's health and activity status. This information is utilized to promote behavior modification, which could help prevent chronic diseases and manage the health of older adults. Despite being interested in SWs, older adults tend to decrease their SW usage as they age. Therefore, understanding the acceptance of SWs among older individuals can facilitate individual health management through digital health technology. This study investigated the factors associated with the acceptance of SWs among older adults in Japan and the variations in the factors by sex. This study utilized data from the 2022 Itabashi Longitudinal Study on Aging, an ongoing cohort study conducted by the Tokyo Metropolitan Institute for Geriatrics and Gerontology. We included 899 eligible individuals aged ≥65 years. Participants were classified into three groups: possessing SW (possessor group), not possessing SW but interested in possession in the future (interest group), and not interested in possession in the future (non-interest group) using a self-administered questionnaire. The level of SW acceptance was operationally defined as follows: low (non-interest group), medium (interest group), and high (possessor group). Further, we evaluated the association of acceptance and purchase intentions of SWs with sociodemographic variables, technology literacy, and health variables. Among the participants, 4.2% possessed SWs, with no significant sex difference (men, 4.2%; women, 4.3%). Among men, age < 75 years, obesity, diabetes, and dyslipidemia were significantly associated with SW acceptance level. Contrastingly, among women, age < 75 years, living alone, higher household income, and a high score for new device use in the technology literacy category were significantly associated with SW acceptance level. Health-related factors were associated with SW acceptance in men, while technology literacy and sociodemographic factors were associated with SW acceptance in women. Our findings may inform the development of sex-specific interventions and policies for increasing SW utilization among older adults in Japan.

Associations of polypharmacy with frailty severity and each frailty phenotype in community-dwelling older adults: Itabashi Longitudinal Study on Aging.

AIM: Although polypharmacy and frailty are concerns in older adults, there is limited understanding of their association, particularly regarding frailty severity and its phenotypes within this population. This study aimed to examine the association between polypharmacy and frailty severity or frailty phenotypes in community-dwelling older Japanese adults. METHODS: This cross-sectional study included 1021 older adults from the Itabashi Longitudinal Study on Aging. Men accounted for 45.4%, and the mean age (standard deviation) was 77.9 (5.1) years. Participants were classified into frail (n = 67), pre-frail (n = 543), and robust (n = 411) groups using the revised Japanese Cardiovascular Health Study criteria. Polypharmacy was defined as using five or more self-reported prescription drugs. Ordinal and binomial logistic regression analyses examined the association between polypharmacy and frailty severity or frailty phenotypes (weight loss, weakness, exhaustion, slowness, and low activity). These models were adjusted for age, sex, body mass index, number of comorbidities, living status, employment status, years of education, as well as drinking and smoking habits. RESULTS: The prevalence of frailty in participants with and without polypharmacy was 10.1% and 5.0%, respectively. Participants with polypharmacy were more likely to have frailty (adjusted odds ratio [95% confidence interval], 1.89 [1.40-2.57]), weight loss (1.81 [1.00-3.27]), weakness (1.50 [1.08-2.09]), and slowness (2.25 [1.29-3.94]) compared with the no-polypharmacy group. CONCLUSIONS: Polypharmacy was associated with frailty severity and three frailty phenotypes. Longitudinal studies are required to investigate whether polypharmacy can predict the development and progression of frailty. Geriatr Gerontol Int 2024; 24: 196-201.

Categorization using the Dementia Assessment Sheet for Community-Based Integrated Care System 8-items (DASC-8) based on cognitive function and activities of daily living predicts frailty, disability and mortality in older adults.

AIM: This longitudinal study aimed to determine whether categorization by the Dementia Assessment Sheet for Community-based Integrated Care System 8-items (DASC-8) is associated with risk of frailty onset, disability, and mortality. METHODS: We analyzed longitudinal data from outpatients aged 65 years and older evaluated for the DASC-8 at the Frailty Clinic. The outcomes during the 3-year follow-up period were (Study A) frailty onset (Kihon Checklist ≥8) and (Study B) disability (new certification of nursing care needs) or mortality. Multivariate Cox regression analyses were performed to examine independent associations between the DASC-8 category and outcomes, and hazard ratios and 95% confidence intervals (CIs) were calculated after adjustment for age, sex, and the presence or absence of diabetes, hypertension, and dyslipidemia. RESULTS: (Study A) Out of the 216 patients without frailty in Categories I or II at baseline, 40 (20.4%) and 11 (55.0%) developed frailty, respectively. The adjusted hazard ratio was 3.62 (95% CI: 1.69-7.76, P < 0.001). (Study B) Out of the 350 patients who did not require long-term care at baseline, disability or death occurred for 20 (7.3%) in Category I, 14 (23.0%) in Category II, and 9 (56.3%) in Category III. The adjusted hazard ratios were 2.40 (Category I vs. II; 95% CI: 1.13-5.11, P = 0.023) and 5.43 (Category I vs. III; 95% CI: 2.23-13.3, P < 0.001). CONCLUSION: Categorization according to DASC-8 is associated with the risk of frailty, disability, and mortality in older patients. Geriatr Gerontol Int 2024; 24: 150-155.

Questionnaire for Medical Checkup of Old-Old is non-inferior to the Kihon Checklist in screening frailty among independent older adults aged 75 years and older: The Itabashi Longitudinal Study on Aging.

AIM: The Questionnaire for Medical Checkup of Old-Old (QMCOO) is a 15-item dichotomous questionnaire developed for the early detection and intervention of frailty in a nationwide health checkup program targeting the old-old (i.e. aged ≥75 years). The Kihon Checklist (KCL) is a 25-item questionnaire widely used for screening and self-monitoring frailty status in administrative settings. With fewer items than the KCL, the QMCOO might expedite the frailty screening process. This study tested whether the QMCOO shows noninferiority in detecting frailty compared with the KCL. METHODS: Overall, 645 participants aged ≥75 years in the Itabashi Longitudinal Study on Aging were assessed for their frailty status according to the revised Japanese version of the Cardiovascular Health Study criteria. They also completed the QMCOO and the KCL simultaneously. We compared the discriminative performance of the two questionnaires using non-inferiority testing with an operationally defined non-inferiority margin of 10% of the area under the receiver operating characteristic curve computed from the KCL. RESULTS: The prevalence of frailty was 8.8%. The area under the receiver operating characteristic curve for the QMCOO in determining frailty was 0.76 (95% CI 0.70, 0.82), and the corresponding area under the receiver operating characteristic curve for the KCL was 0.77 (95% CI 0.69, 0.84). The QMCOO was not inferior to the KCL for frailty discrimination (P for non-inferiority = 0.006). CONCLUSIONS: The accuracy of the QMCOO for determining frailty was not inferior to that of the KCL. The QMCOO might be more acceptable and useful, as it can be applied in a shorter time with fewer questions than the KCL. Geriatr Gerontol Int 2024; 24: 176-181.

Association between dynapenia and cognitive decline in community-dwelling older Japanese adults: The IRIDE Cohort Study.

AIM: Muscle mass and strength correlate with cognitive function; however, it remains unclear whether dynapenia (i.e., muscle weakness with preserved muscle mass) is relevant. This study aimed to explore whether dynapenia is associated with global cognitive function in community-dwelling older Japanese adults. METHODS: This cross-sectional study used data from the Integrated Research Initiative for Living Well with Dementia Cohort Study, which pooled data from five community-based geriatric cohorts. Dynapenia was defined as muscle weakness without muscle mass loss according to the Asian Working Group for Sarcopenia criteria. Cognitive function was assessed using the Mini-Mental State Examination (MMSE). An ordered logistic regression analysis was conducted with dynapenia as the exposure and with cognitive decline stages, defined as an MMSE score of 27-30 for normal cognition, 24-26 for possible cognitive decline, and <24 for cognitive decline, as the outcome, stratified by sex and adjusted for age, muscle mass, education, alcohol consumption, smoking habits, living alone, and non-communicable diseases. RESULTS: We analyzed data for 3338 participants (2162 female) with preserved muscle mass. Of these, 449 (13.5%) had dynapenia, and 79 (2.4%) exhibited cognitive decline. Multivariate odds ratios (95% confidence interval) for cognitive decline among those with dynapenia, compared with those without dynapenia, were 1.51 (1.02-2.24) for males and 2.08 (1.51-2.86) for females. CONCLUSIONS: Muscle weakness is associated with cognitive decline, even in individuals with preserved muscle mass. Further studies are needed to better understand the association between muscle weakness and cognitive decline over time in order to develop dementia prevention strategies for those with dynapenia. Geriatr Gerontol Int 2024; 24: 123-129.

Relationship between phase angle and lower-extremity function in older adults: Itabashi Longitudinal Study on Aging.

OBJECTIVE: Evaluating muscle quality instead of its mass has gained attention in diagnosing sarcopenia. The aim of this study was to examine whether phase angle (PhA) as a bioelectrical impedance analysis (BIA)-derived muscle quality indicator is associated with overall lower extremity function better than appendicular skeletal muscle mass index (ASMI) in community-dwelling older adults. METHODS: This cross-sectional study used data from the Itabashi Longitudinal Study on Aging, a community-based cohort study. A sex-stratified multivariate logistic regression analysis was conducted using PhA and ASMI as exposures, and low physical function defined as short physical performance battery score <10 as the outcome, adjusted for age, being overweight, knee pain, and non-communicable diseases. Discrimination of low physical function was compared using the receiver operating characteristic curve. RESULTS: This study included 1464 participants (age 76 [73-80] y; 757 women), with 58 men (8%) and 66 women (9%) exhibiting low physical function. The multivariate odds ratio (OR; 95% confidence interval [CI]) for low physical function among the highest quartile, compared with the lowest quartile were significant in PhA in multiple sites (e.g., OR, 0.09; 95% CI, 0.03-0.32] for men and 0.12; 95% CI, 0.04-0.33 for women in the left leg) but not in ASMI (OR, 0.51; 95% CI, 0.19-1.34 for men and 0.56; 95% CI, 0.21-1.47 for women). Legs and whole-body PhA outperformed the ASMI in discriminating low physical function (P < 0.001). CONCLUSION: PhA reflected physical function better than ASMI; using PhA instead of ASMI in BIA-based morphometric evaluation may add information on low physical function and enhance the diagnostic value of sarcopenia.