Association between willingness to exercise and incident disability in older adults: a prospective longitudinal cohort study.

PURPOSE: To investigate whether the willingness to exercise (WTE) and exercise habits affect the incidence of disability among older adults. METHODS: This study included 8,354 individuals (72.5 ± 6.2 years, 55.9% female). The participants were divided into three categories based on their WTE: unwillingness to exercise, willingness to exercise (but without exercise habits), and exercise habits. The incidence of disability was prospectively determined within 24 months of the follow-up. Cox regression analysis was used to examine the relationship between WTE and the incidence of disability. RESULTS: Overall, 600 (7.2%), 4,703 (56.3%), and 3,051 (36.5%) participants were classified as unwillingness to exercise, willingness to exercise, and exercise habits, respectively. Compared with the unwillingness to exercise group, the willingness to exercise group (hazard ratio [HR] 0.71, 95%Confidence Interval [CI] 0.52-0.96) and the exercise habits group (HR 0.65, 95%CI 0.46-0.92) had a lower risk of disability incidence. CONCLUSIONS: These results suggest that WTE reduces the risk of disability in older adults. Therefore, the importance of increasing WTE to prevent the occurrence of disabilities is clear. Our results suggest that even though physical activity declines with age, it is important to have the desire to exercise and develop exercise habits.

Prevalence and Prognostic Impact of Multiple Frailty Domain in Japanese Older Adults.

OBJECTIVES: In this observational study, we aimed to evaluate the independent and overlapping effects of multiple frailty domains on long-term care insurance (LTCI) use. DESIGN: Population-based cohort design. SETTING AND PARTICIPANTS: In total, 9804 community-dwelling older adults were recruited from the National Center for Geriatrics and Gerontology-Study of Geriatric Syndromes. METHODS: The physical domain of frailty was assessed using the revised Japanese version of the Cardiovascular Health Study criteria. The cognitive domain of frailty was identified as impairment of memory, attention, executive function, or processing speed using standardized thresholds established for each domain in population-based cohorts. The social domain was operationalized using the National Center for Geriatrics and Gerontology-Social Frailty Scale. The use of LTCI was prospectively determined over 60 months using data extracted from the Japanese long-term care insurance system. RESULTS: The data from 7745 participants were analyzed, of whom 793 (10.2%) required LTCI certification within 60 months (interquartile range: 60-60 months). The Kaplan-Meier curve analysis demonstrated that a high number of frailty domains was associated with incident LTCI use. The proportions of incident LTCI use were 6.0%, 12.4%, 30.1%, and 43.9% for non-frail participants and those with impairments in 1, 2, and 3 frailty domains, respectively. In the multivariate Cox regression model, physical, cognitive, and social domain impairments independently increased the risk of incident LTCI use [physical domain impairment, hazard ratio (HR), 1.67; 95% CI, 1.39-2.01; cognitive domain impairment, HR, 1.59; 95% CI, 1.37-1.84; social domain impairment, HR, 1.26; 95% CI, 1.05-1.50]. CONCLUSIONS AND IMPLICATIONS: Overlapping frailty domains were strongly associated with incident LTCI use among community-dwelling older adults. These findings emphasize the importance of assessing multiple frailty domains and tailoring interventions according to the unique circumstances of older adults to prevent functional disabilities.

Validation of the Optimal University of California Los Angeles Loneliness Scale Cutoff Score in Screening for the Prevention of Disability Occurrence Among Older Japanese Adults.

OBJECTIVES: The association between loneliness and disability is a growing public health priority. While the University of California Los Angeles Loneliness Scale (UCLA-LS) has been internationally used as an indicator for assessing loneliness, its optimal cutoff point in relation to disability occurrence has not yet been examined. Therefore, we aimed to determine the optimal cutoff point of the UCLA-LS regarding future disability. METHODS: This longitudinal cohort study was conducted in Tokai City, Aichi Prefecture, Japan. Overall, 4536 community-dwelling older adults (age: 73.8 ± 5.5 years; females: 55.2%) were followed up for 2 years. The area under the curve of the receiver operating characteristic analysis was calculated to evaluate the optimal cutoff point of the UCLA-LS in relation to future disability occurrence using the Youden index, which maximized the sensitivity and specificity of the UCLAS-LS. A survival analysis was conducted to test this cutoff value's external validity, using the presence or absence of disability occurrence as the dependent variable. RESULTS: The cutoff score of the UCLA-LS in relation to future disability was 44 points. An association was found between new disability occurrence and loneliness based on this cutoff value (hazard ratio: 1.67, 95% confidence interval: 1.29-2.16). CONCLUSIONS: Although cultural context should be taken into account, the optimal cutoff scores for the loneliness scale related to disability identified in this study may be a useful indicator for early recognition of loneliness as a global public health problem and for promoting social participation as one of the disability prevention strategies.

Association between the level of social participation and depressive symptoms among older Japanese adults: a cross-sectional survey.

BACKGROUND: Social participation is recommended for older adults to remain actively involved in daily life. Social participation is a broad concept, ranging from 'interacting with others without doing a specific activity with them' to 'actively contributing to society.' However, previous studies have not taken into account the components of social participation. Depressive symptoms are significant outcomes in older adults. Social participation mitigates these risks owing to its association with reduced mortality and enhanced quality of life. This study aimed to examine the association between the level of social participation and depressive symptoms in community-dwelling older adults. METHODS: We included 17 040 individuals aged ≥65 years. Social participation was categorised into Level 3, interacting with others without doing a specific activity with them; Level 4, engaging in an activity with others; Level 5, helping others; and Level 6, contributing to society, based on a previous study by Levasseur et al. Depressive symptoms were assessed using the 15-item Geriatric Depression Scale. Logistic regression models were used to examine the association between the level of social participation and depressive symptoms. RESULTS: Overall, 15 069 older adults met the inclusion criteria. A higher level of social participation was associated with lower odds ratios (ORs) for depressive symptoms (Level 6 = OR: 0.43, 95% confidence interval (CI): 0.37-0.50; Level 5 = OR: 0.50, 95% CI: 0.41-0.60; and Level 4 = OR: 0.60, 95% CI: 0.52-0.69). Subgroup analyses based on age and sex yielded similar results across all participants. CONCLUSIONS: Among older adults in Japan, a higher level of social participation was associated with lower rates of depressive symptoms. The relationship between depressive symptoms and the levels of social participation may help develop measures to reduce or prevent depressive symptoms in older adults.

Association between social isolation and diversity in food intake by gender in community-dwelling older adults: A cross-sectional study.

AIM: Few studies have investigated the relationship between low dietary variety and clearly defined social isolation by gender. This study explored the association between dietary variety and social isolation, classified by operational definition, separately by gender in community-dwelling older adults. METHODS: This cross-sectional study recruited respondents via mail. A total of 4798 participants aged ≥65 years participated in the on-site assessment. Social isolation was assessed by "lack of conversation," "lack of passive support," "lack of offering support," and "lack of social participation." Dietary variety was evaluated using the Dietary Variety Score (DVS). RESULTS: The participants' median age was 73 (interquartile range 25-75: 69-77) years, and 2147 (44.7%) were male. After adjusting for covariates, with regard to male participants, a lack of offering support (ß = -0.051, P = 0.019) and a lack of social participation (ß = -0.089, P < 0.001) were associated with a low DVS. For female participants, only a lack of social participation was related to a low DVS (ß = -0.067, P < 0.001). A lack of conversation and passive support were not associated with a low DVS for both genders (P >0.05). CONCLUSION: The results indicate that encouraging social participation, regardless of gender, as well as preventing a lack of offering support for others among men, may contribute to improving individuals' DVS. Geriatr Gerontol Int 2024; ••: ••-••.

Combined effects of loneliness and diabetes mellitus on disability incidence among older Japanese adults.

BACKGROUND: Developed countries worldwide face the challenge of aging populations in which loneliness is problematic, leading to mental and physical health issues. Diabetes mellitus (DM) can cause decreased physical activity, reduced functioning, and depressive symptoms. However, how interactions between loneliness and DM influence health outcomes remains unclear. We aimed to determine the effects of loneliness and DM-related complications on the incidence of disability among older individuals. METHODS: We analyzed data from the Japanese National Center for Geriatrics and Gerontology Study of Geriatric Syndromes for community-dwelling adults aged ≥65 years without initial long-term care needs. Loneliness was assessed using the University of California Los Angeles Loneliness Scale, and DM status was determined based on medical history obtained through face-to-face interviews. Disability incidence was identified by monthly tracking of certifications under the Japanese long-term care insurance system. The combined effect of DM and loneliness on care needs was examined using Cox proportional hazard regression models. RESULTS: Among 5,160 participants, 298 (5.8 %) developed incident disabilities within 24 months. Cox models adjusted for potential confounders revealed a significantly increased disability risk among persons with DM and loneliness. Having DM without loneliness and vice versa were not significant risk factors for disability incidence compared with having neither. CONCLUSIONS: The combination of loneliness with DM was a risk factor for disability development among community-dwelling older adults. Loneliness and DM might be interrelated and associated with disability development, suggesting that support along with assessments of mental health and illness might help to avoid disability in this population.

Risk of dementia with hearing impairment and social isolation.

INTRODUCTION: This study aimed to determine whether the concomitance of hearing impairment and isolation with lack of conversation, which is considered self-evident but has not been investigated extensively, is associated with the occurrence of dementia. METHODS: A total of 2745 participants were divided into four groups according to the presence/absence of hearing impairment and isolation with lack of conversation. The association of dementia with hearing impairment and isolation with lack of conversation was analyzed using Cox proportional hazards regression. RESULTS: The combined hearing impairment and isolation with lack of conversation (hazard ratio: 1.69, 95% confidence interval: 1.09-2.61) and non-hearing impairment and isolation with lack of conversation (hazard ratio: 1.60, 95% confidence: 1.07-2.39) were associated with the development of dementia. DISCUSSION: These findings emphasize the importance of promoting high-quality social relationships throughout life by adopting preventive measures against isolation with lack of conversation from the early stage of awareness of hearing impairment. Highlights: Dementia affects 12.9% of those with hearing impairment and isolation.Hearing impairment and isolation are associated with increased risk of dementia.Addressing these risk factors may help reduce the risk of developing dementia.Preventing isolation and promoting quality social relationships is important.

Development of a weighted scoring model for social activities to predict disability incidents among older Japanese adults.

BACKGROUND: Social activities contribute to health improvements in older adults, but methods for evaluating these activities are not yet established. We developed a scoring model for social activity, weighted by specific activities, to assess the association between disability incidence in older adults and social activities. METHODS: Data were obtained from Japan's National Center for Geriatrics and Gerontology Study of Geriatric Syndromes (NCGG-SGS). Social activity was evaluated across 16 domains. Disability was determined using data extracted from Japan's long-term care insurance system. RESULTS: Data from 4998 older adults were analyzed; among them, 422 (8.4 %) developed a disability within 35 months (Interquartile range: 32-39). The Cox proportional hazards model was used to assess 16 domains of social activity. The results yielded risk factors for disability incidence in six social activity domains: work, travel, hobbies, babysitting, family caregiving, and events. The coefficients for these activities were assigned weights of 3, 3, 2, 1, 1, and 1, respectively. The weighted social activity scoring model significantly improved the ability to predict disability incidence when the number of social activities in which individuals participated was considered (social activity score: area under the curve [AUC] 0.691, 95 % confidence interval [CI] 0.664-0.717; number of social activities: AUC 0.681, 95 % CI 0.654-0.707, P = 0.042). CONCLUSIONS: The composite score derived from the weighted social activity scoring model serves as a valuable tool due to its enhanced predictability, which complements established background factors associated with the incidence of disability in older adults.

The Utility of Urinary Titin to Diagnose and Predict the Prognosis of Acute Myocardial Infarction.

Early detection and management are crucial for better prognosis in acute myocardial infarction (AMI). Serum titin, a component of the sarcomere in cardiac and skeletal muscle, was associated with AMI. Thus, we hypothesized that urinary N-fragment titin may be a biomarker for its diagnosis and prognosis. Between January 2021 and November 2021, we prospectively enrolled 83 patients with suspected AMI. Their urinary N-fragment titin, serum high-sensitivity troponin I (hsTnI), creatine kinase (CK), and creatine kinase-MB (CK-MB) were measured on admission. Then, urinary titin was assessed as diagnostic and prognostic biomarker in AMI. Among 83 enrolled patients, 51 patients were diagnosed as AMI. In AMI patients who were admitted as early as 3 h or longer after symptom onset, their urinary titin levels were significantly higher than non-AMI patients who are also admitted 3 h or longer after symptom onset (12.76 [IQR 5.87-16.68] pmol/mgCr (creatinine) and 5.13 [IQR 3.93-11.25] pmol/mgCr, p = 0.045, respectively). Moreover, the urinary titin levels in patients who died during hospitalization were incredibly higher than in those who were discharged (15.90 [IQR 13.46-22.61] pmol/mgCr and 4.90 [IQR 3.55-11.95] pmol/mgCr, p = 0.023). Urinary N-fragment titin can be used as non-invasive early diagnostic biomarker in AMI. Furthermore, it associates with hospital discharge disposition, providing prognostic utility.

Classification of social isolation and factors related to loneliness and life satisfaction among socially isolated individuals.

PURPOSE: To operationally divide social isolation into four categories and examine the factors associated with social isolation and its relationship with loneliness and life satisfaction. METHODS: The participants were community-dwelling older adults aged ≥ 60 years who underwent functional health examinations in Chita City, Aichi, Japan. Multiple regression analysis was used to examine the associations between social isolation, loneliness, and life satisfaction. RESULTS: A total of 5,066 participants (mean age 72.0 ± ± 6.3 years, female: 55.4 %) were included in the study. Multiple regression analysis showed that the number of experiences of social isolation, classified into four categories, was positively correlated with loneliness (ß = 0.188, ΔR2 = 0.244, p < 0.001) and negatively correlated with life satisfaction (ß = -0.076, ΔR2 = -0.178, p < 0.001). CONCLUSIONS: Multiple experiences of social isolation classified into four categories were found to be associated with higher loneliness and lower life satisfaction.

Comparison of water balance among healthy young and old adults and handicapped adults.

The body's water balance is changed by food and beverage intake, metabolism, and excretion. In this study, we performed a cross-sectional study that investigated the changes of water intake and water output in healthy Japanese young and elderly people and handicapped adults. Water balance was assessed by water intake from foods and beverages, metabolic water production, non-renal water losses (NRWL), and urine volume. Most of the parameters did not change with aging in healthy adults. Estimated total water intake (ml/kg/day) increased with aging. In the healthy men, healthy women, and handicapped adults, daily water intake (median [interquartile range]) accounted for 49.4 (41.4-59.9) ml/kg, 42.9 (38.7-51.8) ml/kg, and 50.9 (43.8-74.0) ml/kg, respectively. Water loss from the kidney accounted for 19.2 (16.2-29.2) ml/kg, 22.0 (16.2-26.6) ml/kg, and 27.5 (22.7-47.2) ml/kg, respectively. NRWL accounted for 26.6 (18.5-35.2) ml/kg, 22.4 (16.2-28.8) ml/kg, and 23.5 (19.8-28.5) ml/kg, respectively. Our findings suggest that a daily total water intake of more than 50-55 ml/kg is required to prevent dehydration in healthy and handicapped adults. J. Med. Invest. 70 : 195-199, February, 2023.

Diaper-zero program (prompted voiding care) improves diaper use in nursing home residents.

With an aging population, the number of older adults admitted to nursing homes has increased. Diapers are often used to manage nursing home resident urinary incontinence, yet only one-third of these required assistance from caregivers to urinate. Unnecessary diaper use was reported in 23.9% of peop1e, mostly for precautionary purposes. In this study, the Diaper-zero program caregivers asked residents regularly (every 2-3 h) whether they required voiding and prompted them to void. Over 11 months, the effects on 38 nursing home residents' diaper use, nursing care level, physical activity, daily energy, and water intake were measured. A higher rate of diaper wearing was initially observed with lower daily energy and water intakes at the beginning of the Diaper-zero program, but this association was not observed after 11 months of the program. The diaper usage rate decreased significantly from 71.1% to 47.4% after 11 months. During this period, for all subjects, nursing care level, physical activity, and total daily intakes of energy and water were unchanged. In conclusion, this program enhances the desire to void, minimizing diaper usage, thus protecting the human dignity of nursing home residents. J. Med. Invest. 70 : 221-225, February, 2023.

Umami taste sensitivity is associated with food intake and oral environment in subjects with diabetes.

OBJECTIVE: Dysgeusia is a serious problem in patients with diabetes because it often leads to overeating, which is associated with disease progression. This study aimed to investigate the association between taste sensitivity, eating habits, and the oral environment. SUBJECTS AND METHODS: In this cross-sectional study of 75 subjects with diabetes, gustatory function was assessed using the whole-mouth method, and lingual taste receptor gene expression was measured by real-time PCR. Food intake was evaluated using a food frequency questionnaire based on food groups. The oral environment was assessed using xerostomia and periodontal comprehensive examination. RESULTS: In total, 45.3%, 28.0%, and 18.7% of subjects showed lower umami taste sensitivity, low sweet taste sensitivity, and low salt taste sensitivity, respectively. Lower umami sensitivity correlated with lower estimated glomerular filtration rate and higher energy-source food intake. Subjects with diabetes with higher plaque control record showed significantly higher T1R3 gene expression than those with lower plaque control record. CONCLUSION: Reduced umami taste sensitivity is associated with decreased renal function and high energy food intake in diabetes. Subjects with diabetes with higher plaque control record showed significantly higher T1R3 gene expression, suggesting that the oral environment affects taste gene expression. J. Med. Invest. 70 : 241-250, February, 2023.

Taste receptor gene expression is associated with decreased eGFR in patients with diabetes.

Dysgeusia is not only associated with zinc deficiency but also with certain drugs or diseases, including diabetes and renal failure. It often lowers the patient's quality of life and hinders access to proper nutrition. The underlying mechanism is unclear and there is a lack of awareness among patients. Here, we focused on lingual taste receptor gene expression in diabetes and elucidated the relationship between taste receptor gene expression and renal function. Forty-seven patients with diabetes and 10 healthy subjects (control group) were enrolled. Lingual foliate papillae were scraped and the derived cDNA was quantified by real-time polymerase chain reaction. Dysgeusia was assessed using SALSAVE?. All statistical analyses were performed using JMP? software 13. The expression of T1R1 and T1R2 was significantly upregulated in type 2 diabetes patients as compared with that in healthy subjects (P<0.01) but did not change in type 1 diabetes patients. T1R3 expression positively correlated and Scnn1 expression negatively correlated with estimated glomerular filtration rate, suggesting that altered taste receptor gene expression could reflect impaired renal function. Thus, alterations in T1R3 and Scnn1 expression in diabetes correlated with renal function. Taste receptor gene expression dysregulation could indicate dysgeusia associated with impaired renal function in patients with diabetes. J. Med. Invest. 69 : 120-126, February, 2022.

Dietary supplementation with monosodium glutamate with dietary balance such as protein, salt and sugar intake with increasing T1R3 taste receptor gene expression in healthy females.

We previously showed that chemotherapy-induced dysgeusia was associated with lingual taste receptor gene expression, and monosodium glutamate (MSG) improved dysgeusia by upregulating taste 1 receptor 3(T1R3) gene expression. In recent years, decreased taste sensitivity has also been reported in some young people, and these are partly due to their disordered eating habits. From these background, we investigated the effects of MSG supplementation on taste receptor expression and dietary intake in healthy females. Fifteen young healthy volunteers were enrolled for the present crossover study and divided in two groups (dietary supplementation with MSG at 2.7 g / day or 0.27 g / day). The relative expression of T1R3, a subunit of both umami and sweet taste receptors, in the tongue was assessed by quantitative PCR analysis. Food intake was assessed by food frequency questionnaire (FFQg), and body composition was measured using Omron HBF-701. T1R3 expression levels in the tongue and taste sensitivity increased significantly in participants who consumed <10 g of MSG daily, whereas no alteration was observed in participants who consumed >10 g of MSG daily. Furthermore, protein, fat, and carbohydrate (PFC) balance and salt and sugar intake improved by MSG supplementation. In conclusion, MSG supplementation increased T1R3 expression in the tongue and improved dietary balance. J. Med. Invest. 68 : 315-320, August, 2021.

Sudachi peel extract powder including the polymethoxylated flavone sudachitin improves visceral fat content in individuals at risk for developing diabetes.

In vitro and animal studies have indicated that extracts from the peel of the Japanese Citrus sudachi, including sudachitin, ameliorate hyperlipidemia and reduce obesity. Sudachitin, a polymethoxylated flavone, has been reported as having favorable effects on lipid and glucose metabolism but results from clinical trials have been inconsistent. The aim of this study was to determine the effect of consuming capsules of sudachi peel extract powder on visceral fat in Japanese men and women in a randomized controlled trial. This was a 12-week randomized, double-blind, placebo-controlled trial involving 41 participants aged 30-65 years with BMI 23-30 kg/m2, randomly allocated to receive either sudachi peel extract powder (sudachitin 4.9 mg/day, n = 21) or placebo (n = 20) of identical appearance. The primary outcome measure was visceral fat mass, assessed during intervention. Thirty-eight of the 41 subjects completed the protocol. Compared with placebo, sudachi peel extract powder significantly reduced the ratio of visceral fat to subcutaneous fat, and moderately reduced waist circumference, a metabolic syndrome marker. Glycemic control and lipid profile were not changed significantly in these subjects. Consumption of capsules of sudachi peel extract powder favorably improves the ratio of visceral fat to subcutaneous fat in individuals at risk for developing diabetes, especially in individuals with large visceral fat area, while not adversely affecting glycemic control.