• Journal of the Korean Data and Information Science Society
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• v.17 no.3
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• pp.999-1007
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• 2006

The semiparametric gamma frailty models have been often used for multivariate survival analysis because they give an explicit marginal likelihood. The commonly used estimation procedure is the profile likelihood method based on marginal likelihood, which provides the same parameter estimates as the EM algorithm. In this paper we show in finite samples the standard profile-likelihood method can lead to an underestimation of parameters, particularly for the frailty parameter. To overcome this problem, we propose an adjusted profile-likelihood method. For the illustration a numerical example and a small-sample simulation study are presented.

• Journal of Nutrition and Health
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• v.54 no.6
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• pp.631-643
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• 2021

Purpose: Frailty is a clinical syndrome in older adults, and adequate nutrition is a modifiable factor in preventing the condition. The current study aims to investigate the association between frailty and dietary intake in the Korean elderly. Methods: This cross-sectional study included data from the 2018 Korean National Health and Nutrition Examination Survey of 1,268 subjects (535 men and 733 women) aged 65 years or older. Frailty was defined as having more than three of the following 5 modified Fried frailty phenotype criteria: unintentional weight loss, exhaustion, walking difficulties, weakness, and low physical activity. Dietary intake was assessed by applying the one-day 24-hour dietary recall. The association between frailty and dietary intakes were analyzed by multiple logistic regression. Results: Totally, 9.7% men and 21.9% women were classified as the frail group. Increasing levels of frailty were proportional to a decreased mean nutrient adequacy ratio in both genders. Moreover, the total food intake was significantly low in the frail elderly. In male subjects, multiple logistic regression analyses after adjusting covariates showed that the odds ratio (OR) of frailty in the highest tertile of the consumption of fruits (OR [95% confidence interval, CI] = 0.34 [0.13-0.93], p-trend = 0.021) were significantly lower than values obtained in the lowest tertile. In females, the highest tertile of fish and shellfish intake showed a significantly lower OR for frailty (OR [95% CI] = 0.55 [0.30-0.99], p-trend = 0.045), as compared with the lowest tertile. Conclusion: The present study indicates that high intake of fruits for men, and fish and shellfish for women, are probably linked with lowering the risk of frailty in the elderly.

• Journal of Korean Academic Society of Home Health Care Nursing
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• v.26 no.1
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• pp.5-18
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• 2019

Purpose: Frailty is associated with an increased risk of adverse health outcomes. We aimed to review the relationships between frailty and health outcomes in community-dwelling Korean elderly individuals. Methods: Whittemore and Knafls' framework for conducting integrative reviews was used. PubMed, Cumulative Index to Nursing and Allied Health Literature, and six Korean databases were searched. For analysis, the study included articles written in English and Korean published between January 1960 and June 2018. Of the total 1,488 studies found in the databases, we analyzed 15 studies that met the quality of the evaluation criteria. Results: The prevalence of frailty in Korean elderly individuals ranged from 6.5% to 11.7% when divided into three levels of frailty. The health outcomes assessed in relation to frailty were divided into five domains: quality of life, physical health, psychosocial health, health behavior, and health care quality. Frailty was negatively associated with all five domains. Conclusions: Our study suggested that nurses should be aware of the limitations in the physical and cognitive functions of frail elderly individuals and provide tailored interventions for Korean elderly individuals. Furthermore, a large-scale study is needed to develop the Korean model of the frailty assessment tool and to verify the conceptual model of this study.

• Journal of the Korean Society of Industry Convergence
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• v.25 no.5
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• pp.725-739
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• 2022

This study conducted with 268 female elderly who visited welfare center and senior citizen center in Changwon city to identify the dietary status according to social frailty stage using nutrition quotient for elderly (NQ-E). As a result of the survey, 75.0% of the elderly had no nutrition education. The elderly in social frailty stage was 43.7%, pre-frail was 35.1%, and robust was 21.2%. The scores of NQ-E (61.65), balance (47.78), moderation (86.18), and dietary behavior (55.23) were within the medium-high grade, while diversity (48.37) was within the medium-low grade. Among the balance factor item, there was a significant difference only in the frequency of fruit intake according to social frailty stage (p<0.05). Among the diversity factor item, there were significant differences in vegetable intake (p<0.05) and the rate of eating alone (p<0.001) according to social frailty stage. Among the dietary behavior factor item, there were significant differences in whether to strive for a healthy diet (p<0.05), exercise time and depression (p<0.001), and subjective recognition rate of health (p<0.01) according to social frailty stage. Based on these results, education focusing on various food intake is needed, and continuous support from the government and local governments is needed to connect the social support network of the elderly and support programs to prevent them from going to social frailty stage.

• Journal of Yeungnam Medical Science
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• v.37 no.4
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• pp.296-301
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• 2020

The geriatric population is at a greater risk of postoperative complications than young adults. This risk is associated with the physiologic decline seen in this population known as frailty. Unlike fitter patients, frail patients who undergo operative treatment have a greater likelihood of developing postoperative complications and endure prolonged hospital stays. This circumstance is comparable to the urological status. Therefore, tolerable measurement of frailty as a domain of preoperative health status has been suggested to ascertain vulnerability in elderly patients. In this review, we will elaborate on the concept of frailty and examine its importance with respect to surgical complications, focusing on the urological status.

• Journal of Korean Society for Quality Management
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• v.26 no.4
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• pp.111-123
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• 1998

We consider the problem of modeling count data where the observation period is determined by the life time of the system under study. We assume random effects or a frailty model to allow for a possible association between the death times and the counts. We assume that, given a random effect or a frailty, the death times follow a Weibull distribution with a hazard rate. For the counts, given a frailty, a Poisson process is assumed with the intensity depending on time. A gamma distribution is assumed for the frailty model. Maximum likelihood estimators of the model parameters are obtained. A model for the time to death and the number of failures system received is constructed and consequences of the model are examined.

• International Journal of Advanced Culture Technology
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• v.11 no.3
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• pp.131-141
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• 2023

This study aimed to identify the determinants of physical frailty among the old-old adults in rural Korean communities. A total of 191 individuals aged 75 and older were included in the study, with the majority being female. Participants were classified into healthy (n=47), pre-frail (n=54), and frail (n=90) groups. Significant differences were found across these groups in terms of age, gender, education level, depression, and nutritional status. Multiple logistic regression analysis revealed that age (OR=1.16), depression (OR=0.21), malnourishment (OR=10.85), and short physical performance ability (OR=0.70) were significant predictors of physical frailty. These findings underscore the multifaceted nature of physical frailty among old-old adults in urban-rural complex communities and highlight the need for comprehensive and integrated interventions. Such interventions should consider not only physical factors but also broader health conditions and socio-demographic influences impacting the elderly. Further research is needed to develop and evaluate interventions that address these determinants and promote health equity among the elderly population in urban-rural complex communities

• Communications for Statistical Applications and Methods
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• v.25 no.5
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• pp.471-488
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• 2018

In this paper, we propose extending proportional hazards frailty models to allow a discrete distribution for the frailty variable. Having zero frailty can be interpreted as being immune or cured. Thus, we develop a new survival model induced by discrete frailty with zero-inflated power series distribution, which can account for overdispersion. This proposal also allows for a realistic description of non-risk individuals, since individuals cured due to intrinsic factors (immunes) are modeled by a deterministic fraction of zero-risk while those cured due to an intervention are modeled by a random fraction. We put the proposed model in a Bayesian framework and use a Markov chain Monte Carlo algorithm for the computation of posterior distribution. A simulation study is conducted to assess the proposed model and the computation algorithm. We also discuss model selection based on pseudo-Bayes factors as well as developing case influence diagnostics for the joint posterior distribution through ${\psi}-divergence$ measures. The motivating cutaneous melanoma data is analyzed for illustration purposes.

• Nutrition Research and Practice
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• v.17 no.5
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• pp.1007-1018
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• 2023

BACKGROUND/OBJECTIVES: This study aimed to examine whether the tailored home-delivered meal (HDM) services included nutrition counseling impacts alleviating self-rated frailty among low-income older adults in Korea. SUBJECTS/METHODS: Pre- and post-test were implemented on May 27 and on November 25 in 2019 during 3 weeks, respectively, before and after the 6 months intervention program. Participants completed a questionnaire measuring frailty, malnutrition, food security, depression, and underlying diseases. Initially, 136 older adults were selected as participants for this study, they were recipients of a free meal program from 2 senior welfare centers in Seoul, the final sample size of those who completed the intervention program was 117 (female 70.9%, male 29.1%). Statistical analyses were conducted with IBM SPSS package program, paired t-test and χ² test to validate the test. RESULTS: There were statistically significant differences in the score of the Tilburg Frailty Indicator (TFI) before and after receiving the tailored HDM services (pre-test 9.46, post-test 2.8, P < 0.01). The differences in the score of TFI by 3 risk groups at the pre-test decreased as a result of receiving these services. CONCLUSIONS: The tailored HDM services alleviated the self-rated frailty of low-income older adults with limited mobility in a community setting. Based on the positive outcomes this study could be applied to developing social services for aging in place.

• 한국노년학
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• v.38 no.4
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• pp.891-903
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• 2018

This study investigated the relation between frailty, social support, and health-related quality of life to provide basic data to improve the health-related quality of life of old-old elderly who are a high risk group for frailty. For this descriptive study, one-on-one interviews with structured questionnaires were conducted for elderly aged 75 years or older at elderly welfare facilities in K county from March 01 to 31 in 2016, and a total of 211 elderly were interviewed. The collected data were analyzed by t-test, Pearson's correlation coefficient, and path analysis using SPSS/WIN and AMOS 18.0 program. For the differences between the age groups, those aged over 80 years had a significantly higher frailty (t=-2.51, p=.013) and a lower health-related quality of life than those aged below 80 years (t=3.29, p=.001); however, there was no significant difference in social support (t=1.28, p=.201). The correlation between frailty, social support and health-related quality of life showed that as frailty became higher, social support (r=-.21, p=.003) and health-related quality of life (r=-.65, p<.001) were significantly lower, and health-related quality of life was significantly higher with a higher social support (r=.18, p=.010). As a result of investigating the mediating effects of frailty between social support and health-related quality of life, social support had a significant direct effect on frailty (${\beta}=-.21$, p=.016) and frailty had a significant direct effect on health-related quality of life (${\beta}=-.06$, p=.004); however, social support had no significant direct effect on health-related quality of life (${\beta}=.00$, p=.562). Social support had a significant indirect effect on health-related quality of life and a mediating effect on frailty (${\beta}=.01$, p=.012); therefore, the full mediation effect of frailty between social support and health-related quality of life was verified. Social support prevents frailty, and improving frailty enhances health-related quality of life. Therefore, it is necessary to develop a multifactorial frailty prevention program that includes age-specific social support strategies to improve the health-related quality of life in old-old elderly.