Background: This study aimed to develop an instrument for assessing physical functioning among adults aged 50 years or older living in the community. Methods: Based on a review of various national health surveys and cohort studies, a 144-item bank was constructed for assessing physical functioning. Focus group interviews were conducted among adults aged 50 years or older to investigate their level of understanding of 60 selected items, followed by a pretest of the items on a nationally representative sample (n=508). The final 25-item questionnaire was tested on an independent sample (n=259) for validity and reliability based on classical test and item response theories. Predictive validity at the 6-month follow-up was tested in a separate sample (n=263). Results: The newly developed Life Functioning (LF) scale assessed the dimensions of functional limitations, disabilities, and social activities. The scale satisfied a one-dimensionality assumption with good item fit and demonstrated criterion validity, construct validity, high internal consistency (Cronbach’s alpha=0.93), and test-retest reliability (intra-class correlation coefficient=0.84; 95% confidence interval, 0.76–0.89). The LF scale comprised 25 items with a total score ranging from 0 to 100. Higher scores indicated higher levels of functioning. The LF score was significantly associated with the Physical Functioning score at 6 months. Conclusion The LF scale was developed to assess the physical functioning of people in their late midlife or older. Future studies should test the instrument on a national sample and evaluate its application in diverse population subgroups.

Background: This study aimed to develop an instrument for assessing physical functioning among adults aged 50 years or older living in the community. Methods: Based on a review of various national health surveys and cohort studies, a 144-item bank was constructed for assessing physical functioning. Focus group interviews were conducted among adults aged 50 years or older to investigate their level of understanding of 60 selected items, followed by a pretest of the items on a nationally representative sample (n=508). The final 25-item questionnaire was tested on an independent sample (n=259) for validity and reliability based on classical test and item response theories. Predictive validity at the 6-month follow-up was tested in a separate sample (n=263). Results: The newly developed Life Functioning (LF) scale assessed the dimensions of functional limitations, disabilities, and social activities. The scale satisfied a one-dimensionality assumption with good item fit and demonstrated criterion validity, construct validity, high internal consistency (Cronbach’s alpha=0.93), and test-retest reliability (intra-class correlation coefficient=0.84; 95% confidence interval, 0.76–0.89). The LF scale comprised 25 items with a total score ranging from 0 to 100. Higher scores indicated higher levels of functioning. The LF score was significantly associated with the Physical Functioning score at 6 months. Conclusion The LF scale was developed to assess the physical functioning of people in their late midlife or older. Future studies should test the instrument on a national sample and evaluate its application in diverse population subgroups.

Background: This study aimed to develop an instrument for assessing physical functioning among adults aged 50 years or older living in the community. Methods: Based on a review of various national health surveys and cohort studies, a 144-item bank was constructed for assessing physical functioning. Focus group interviews were conducted among adults aged 50 years or older to investigate their level of understanding of 60 selected items, followed by a pretest of the items on a nationally representative sample (n=508). The final 25-item questionnaire was tested on an independent sample (n=259) for validity and reliability based on classical test and item response theories. Predictive validity at the 6-month follow-up was tested in a separate sample (n=263). Results: The newly developed Life Functioning (LF) scale assessed the dimensions of functional limitations, disabilities, and social activities. The scale satisfied a one-dimensionality assumption with good item fit and demonstrated criterion validity, construct validity, high internal consistency (Cronbach’s alpha=0.93), and test-retest reliability (intra-class correlation coefficient=0.84; 95% confidence interval, 0.76–0.89). The LF scale comprised 25 items with a total score ranging from 0 to 100. Higher scores indicated higher levels of functioning. The LF score was significantly associated with the Physical Functioning score at 6 months. Conclusion The LF scale was developed to assess the physical functioning of people in their late midlife or older. Future studies should test the instrument on a national sample and evaluate its application in diverse population subgroups.

Objective: Apolipoprotein E (APOE) genotype is associated with risk of Alzheimer’s disease (AD), but the association ofAPOE ε4 allele with longitudinal medial temporal lobe atrophy (MTA) has been controversial. This study aims to evaluate the effect of APOE genotype on longitudinal MTA over a 2-year period in cognitively impaired patients with amyloid deposition. Methods: This retrospective longitudinal study included 65 cognitively impaired subjects with amyloid deposition (subjective memory impairment, mild cognitive impairment, and mild AD). Participants were divided into carriers (n=27) and non-carriers (n=38) of the ε4 allele. The main outcome is longitudinal reduction of medial temporal lobe (hippocampus, entorhinal cortex, and parahippocampal gyrus) over 2 years. Analysis of covariance was conducted to compare the differences in longitudinal MTA between groups, controlling for covariates. Results: At baseline, hippocampal volume was 4.6% smaller (6.38±1.13 vs. 6.69±0.83, p=0.026) and entorhinal thickness was6.4% thinner (3.51±0.57 vs. 3.75±0.52, p=0.033) in APOE ε4 carriers than non-carriers. Furthermore, APOE ε4 carriers had significantly 72% greater longitudinal hippocampal atrophy compared to non-carriers (-0.43±0.30 vs. -0.25±0.31, p=0.041). Conclusion Our findings of baseline or longitudinal MTA in APOE ε4 carriers suggest that APOE ε4 genotype may contrib-ute to underlying pathophysiology of medial temporal lobe in AD.

Background: This paper examines whether various types of internet use mediated or moderated the relationship between age and cognitive function. Methods: Using 2020 National Survey of Older Koreans, the data of 8,639 adults aged 65 or over were analyzed by complex sample analysis using chi-square test, t-test, multiple regression analysis, and Sobel’s test. Results: All types of internet use were significantly associated with cognitive function and played a significant mediating effect in the relationship between age and cognitive function. Internet use for information searching was the most protective for cognitive function (β=1.902, P<0.001), while Internet use for interpersonal communication exhibited the greatest mediating effect in the relationship between age and cognitive function (Age: β=–0.131, P<0.001→ β=–0.079, P<0.001). The influence of age on cognitive function moderated by all types of internet use. Conclusions This underscores the need to consider various types of internet use when creating nonpharmacological interventions aimed at delaying age-associated cognitive decline in community-dwelling older adults.

Objective: The purpose of this study is to investigate the association of the apolipoprotein E (APOE) e4 genotype with cognition, brain volume, glucose metabolism, and amyloid deposition in patients with Alzheimer disease (AD). Methods: This is cross-sectional study of 69 subjects with AD. All subjects were divided into carriers and non-carriers of the e4 allele. Forty APOE e4 carriers and 29 APOE e4 non-carriers underwent neuropsychological, structural magnetic resonance imaging, [18F]fluorodeoxyglucose positron emission tomography scans (PET) and [18F]florbetaben amyloid PET. Analysis of co-variance was conducted to compare the differences on cognition, brain volume, glucose metabolism and amyloid deposition between APOE e4 carriers and non-carriers after controlling demographics. Results: APOE e4 carriers had 50% lower scores of Seoul Verbal Learning Test (delayed recall) compared to non-carriers (0.88±1.65 vs. 1.76±1.75, p<0.05). However, APOE e4 carriers performed better on other cognitive tests than non-carriers (Korean version of Boston Naming Test [11.04±2.55 vs. 9.66±2.82, p<0.05], Rey Complex Figure Test [25.73±8.56 vs. 20.15±10.82, p<0.05], and Stroop test [color response] [48.28±26.33 vs. 31.56±27.03, p<0.05]). APOE e4 carriers had slightly smaller hippocampal volume than non-carriers (3.09±0.38 vs. 3.32±0.38, p<0.05), but greater total brain cortical thickness (1.45±1.55 vs. 1.37±1.24, p<0.05). Amyloid deposition did not differ significantly between APOE e4 carriers and non-carriers, and no signifi-cant difference in glucose metabolism was found between groups. Conclusion We found that APOE e4 genotype is associated with cognition, brain volume in AD, suggesting that APOE e4 genotype could play an important role in the underlying pathogenesis of AD.

OBJECTIVES: This study aimed to investigate changes in health behaviors, including cigarette smoking, alcohol drinking, physical activity, dietary behaviors, and obesity, before and during the coronavirus disease 2019 (COVID-19) pandemic using the Korea Youth Risk Behavior Survey (KYRBS) database. METHODS: KYRBS data from 2015 to 2021 were used in this study. Differences in health behaviors between before (pre-pandemic period: 2018-2019) and during (pandemic period: 2020-2021) the pandemic were examined. Differences were compared using linear regression and the chi-square test considering the complex survey design after adjusting for grade level. RESULTS: The prevalence of current cigarette smoking and current alcohol drinking significantly decreased in both male and female students during the pandemic compared to the pre-pandemic period. However, the prevalence of obesity significantly increased in both male and female students during the same period. When examining physical activity and dietary behaviors closely related to obesity, fast food consumption increased and fruit consumption decreased during the pandemic in both male and female students, whereas no significant changes in physical activity were observed in either male or female students. CONCLUSIONS The deterioration of adolescent dietary behaviors and an increase in the prevalence of obesity can increase the future disease burden, and concerted efforts at the individual and national levels are needed to reduce obesity and promote healthy dietary behaviors.

OBJECTIVES: This study was to examine the changes in dietary habits and food and nutrient intakes between before (2019) and during (2020) the coronavirus disease 2019 (COVID-19) pandemic from the Korea National Health and Nutrition Examination Survey (KNHANES). METHODS: A total of 54,995 participants aged ≥19 years who participated in the 2011-2020 KNHANES were included. The 10-year trend (2011-2020) and differences between 2019 and 2020 for dietary habits and food and nutrient intakes were estimated using SAS. RESULTS: In the past 10 years (2011-2020), the dietary habits (increase in skipping meals and eating out), food intake (increase in meats and decrease in fruits and vegetables), and nutrient intake (increase in fat and decrease in sodium) in adults have changed. When comparing between 2019 and 2020, there were 4.6%p decrease in the eating out more than once a day. On the other hand, there were no significant differences in the intakes of food, energy and most of nutrients between 2019 and 2020, except for the proportion of energy intake from fat (1.0%p increase) and carbohydrate (1.0%p decrease). CONCLUSIONS Although a change in dietary habits from before to during the COVID-19 pandemic was observed, food and nutrient intakes have not deteriorated markedly and appear similar to the trends in the past 10 years. Throughout the COVID-19 pandemic, it is necessary to monitor the effects of changes in dietary habits on health as well as food and nutrient intakes.

OBJECTIVES: We aimed to study the effects of the coronavirus disease 2019 (COVID-19) pandemic on adolescents’ mental health in Korea. METHODS: We used data from the Korea Youth Risk Behavior Survey 2018-2021 with 227,139 students aged 12-18 years. We estimated the differences in depressive symptoms, suicidal ideation, and stress perception before (2018-2019) and during (2020-2021) the pandemic, as well as before (2019), the first year (2020) of, and the second year (2021) of the pandemic. We also examined whether COVID-19 is statistically associated with mental health. RESULTS: In both male and female adolescents, the prevalence of depressive symptoms, suicidal ideation, and stress perception was higher in the “not living with family,” “low household economic status,” and “self-rated unhealthy status” subgroups. The prevalence of depressive symptoms and stress perception was higher in middle school students. Adolescents were less likely to experience depressive symptoms (adjusted odds ratio [aOR], 0.86; 95% confidence interval [CI], 0.83 to 0.89), suicidal ideation (aOR, 0.80; 95% CI, 0.76 to 0.83), and stress perception (aOR, 0.76; 95% CI, 0.74 to 0.79) in 2020 than in 2019. However, there were more depressive symptoms (aOR, 1.06; 95% CI, 1.02 to 1.09), suicidal ideation (aOR, 1.15; 95% CI, 1.10 to 1.21), and stress perception (aOR, 1.19; 95% CI, 1.16 to 1.23) in 2021 than in 2020. CONCLUSIONS The COVID-19 pandemic had positive impacts on mental health of adolescents in its early stages but has had negative impacts as the pandemic continues. Attention should be paid to adolescents who are particularly vulnerable to the mental health effects of the pandemic.

OBJECTIVES: This study aimed to analyze the changes in chronic disease management indicators, including hypertension, diabetes mellitus, and hypercholesteremia, from 2010-2020 and before (2019) and during (2020) the coronavirus disease 2019 (COVID-19) pandemic. METHODS: This study included 58,504 individuals aged ≥30 years who participated in the Korea National Health and Nutrition Examination Survey 2010-2020. Trends in the prevalence, awareness, treatment, and control of chronic diseases and the difference in those between before and during the COVID-19 pandemic were analyzed using the SAS program PROC SURVEYREG. RESULTS: From 2010-2020, the awareness, treatment, and control in adults aged ≥30 years for hypertension and hypercholesterolemia continuously improved, whereas no significant change in the management indicators of diabetes mellitus was observed. The prevalence of hypertension, diabetes mellitus, and hypercholesterolemia in men increased from before to during the COVID- 19 pandemic. However, there was no significant change in the management indicators of hypertension and diabetes mellitus in men and women, and the awareness, treatment, and control rates for hypercholesterolemia increased by 5.5%p, 6.9%p, and 4.1%p respectively. CONCLUSIONS In 2020, the first year of the COVID-19 pandemic, the prevalence of hypertension, diabetes mellitus, and hypercholesterolemia increased, but the management indicators of the chronic diseases did not significantly deteriorate. Considering the ongoing COVID-19 pandemic, it is necessary to monitor changes in chronic disease management indicators and to develop efficient and accessible chronic disease prevention and management programs.