Association of Change in Smoking Status and Subsequent Weight Change with Risk of Nonalcoholic Fatty Liver Disease

Background/Aims@#Smoking is considered a risk factor for the development of nonalcoholic fatty liver disease (NAFLD). However, the association of a weight change after a change in smoking status and the risk of NAFLD remains undetermined. @*Methods@#This study used the Korean National Health Insurance Service-National Sample Cohort. Based on the first (2009 to 2010) and second (2011 to 2012) health examination periods, 139,180 adults aged at least 40 years were divided into nonsmoking, smoking cessation, smoking relapse, and sustained smoking groups. NAFLD was operationally defined using the fatty liver index. The adjusted odds ratio (aOR) and 95% confidence interval (CI) were calculated using multivariable-adjusted logistic regression. @*Results@#Compared to nonsmoking with no body mass index (BMI) change, the risk of NAFLD was significantly increased among subjects with BMI gain and nonsmoking (aOR, 4.07; 95% CI, 3.77 to 4.39), smoking cessation (aOR, 5.52; 95% CI, 4.12 to 7.40), smoking relapse (aOR, 7.51; 95% CI, 4.81 to 11.72), and sustained smoking (aOR, 6.65; 95% CI, 5.33 to 8.29), whereas the risk of NAFLD was reduced among participants with BMI loss in all smoking status groups. In addition, smoking cessation (aOR, 1.76; 95% CI, 1.35 to 2.29) and sustained smoking (aOR, 1.64; 95% CI, 1.39 to 1.94) were associated with higher risk of NAFLD among participants with no BMI change.The liver enzyme levels were higher among participants with smoking cessation and BMI gain. @*Conclusions@#Monitoring and management of weight change after a change in smoking status may be a promising approach to reducing NAFLD.

Current Status of Physical Activity in South Korea / 가정의학회지

The health benefits of physical activity have been well established. However, more than a quarter of the adult population in the world is insufficiently active (not performing at least 150 minutes of moderate-intensity physical activity per week, 75 minutes of vigorous-intensity physical activity per week, or any equivalent combination of the two), and there has been little improvement since 2001. In South Korea, the prevalence of insufficient physical activity was 54.4% in adults and 94.1% in adolescents in 2020. There was continuous decrease in the prevalence of sufficient aerobic physical activity, from 58.3% in 2014 to 45.6% in 2020. However, daily duration of sedentary behavior increased from 7.5 to 8.6 hours in the same period. Interventions to promote physical activity are necessary in various fields including clinical and policy approaches. As physical activity has decreased during the coronavirus disease 2019 pandemic, safer and more effective strategies to promote physical activity are required.

Metabolic Dysfunction-Associated Fatty Liver Disease Better Predicts Incident Cardiovascular Disease

Background/Aims@#Metabolic dysfunction (MD)-associated fatty liver disease is a new positive diagnostic criterion based on hepatic steatosis and MD. However, a comprehensive evaluation on the association of MD and hepatic steatosis with incident cardiovascular disease (CVD) has yet to be performed. @*Methods@#This retrospective cohort study included 333,389 participants from the Korean National Health Insurance Service database who received a health examination between 2009 and 2010. Hepatic steatosis was defined using the Korean National Health and Nutrition Examination Survey-derived nonalcoholic fatty liver disease scoring system. Cox proportional hazards regression was adopted to determine the adjusted hazard ratio (aHR) with 95% confidence interval (CI) for CVD according to the presence of hepatic steatosis and MD, as well as the composite term. @*Results@#This study included 179,437 men and 153,952 women with a median age of 57 years.Hepatic steatosis with MD (aHR, 2.00; 95% CI, 1.89 to 2.13) and without MD (aHR, 1.30; 95% CI, 1.10 to 1.54) significantly increased the risk of CVD compared to no steatosis without MD (reference). However, steatosis revealed no significant difference in the risk of CVD compared to no steatosis among participants with one MD (aHR, 1.09; 95% CI, 0.91 to 1.30). In participants with steatosis, the presence of one and ≥2 MDs had aHR values of 1.25 (95% CI, 0.87 to 1.79) and 1.71 (95% CI, 1.22 to 2.41), respectively, compared to no MD. @*Conclusions@#Combined consideration of hepatic steatosis and MD was significantly associated with increased CVD risk and showed better predictive performance for CVD than hepatic steatosis or MD alone.

Association of non-alcoholic fatty liver disease with incident dementia later in life among elder adults

Background/Aims@#Accumulating evidence suggests a link between non-alcoholic fatty liver disease (NAFLD) and brain health. However, population-based evidence on the association between NAFLD and dementia remains unclear. This study was conducted to determine the association between NAFLD and incident dementia. @*Methods@#The study population included 608,994 adults aged ≥60 years who underwent health examinations between 2009 and 2010. Data were collected from the Korean National Health Insurance Service database. NAFLD was assessed using the fatty liver index (FLI). A Cox proportional hazards regression model was used to determine the association between NAFLD and dementia. @*Results@#During the 6,495,352 person-years of follow-up, 48,538 participants (8.0%) developed incident dementia. The participants were classified into low (FLI <30), intermediate (FLI ≥30 and <60), and high (FLI ≥60) groups. In the overall study population, the FLI groups were associated with a risk of dementia (P for trend <0.001). After propensity score matching, a low FLI was associated with a reduced risk of dementia (adjusted hazard ration [aHR], 0.96; 95% confidence interval [CI], 0.93–0.98; P=0.002), whereas a high FLI (NAFLD) was associated with an increased risk of dementia (aHR, 1.05; 95% CI, 1.02–1.08; P=0.001). A higher risk of dementia in the high FLI group than in the intermediate FLI group was attributed to Alzheimer’s disease (aHR, 1.04; 95% CI, 1.01–1.07; P=0.004) rather than vascular dementia (aHR, 0.94; 95% CI, 0.75–1.18; P=0.602). @*Conclusions@#NAFLD was associated with an increased risk of dementia, which was attributed to an increased risk of Alzheimer’s disease.

Sedentary Lifestyle: Overview of Updated Evidence of Potential Health Risks / 가정의학회지

One-third of the global population aged 15 years and older engages in insufficient physical activities, which affects health. However, the health risks posed by sedentary behaviors are not well known. The mean daily duration of sedentary behavior is 8.3 hours among the Korean population and 7.7 hours among the American adult population. Sedentary lifestyles are spreading worldwide because of a lack of available spaces for exercise, increased occupational sedentary behaviors such as office work, and the increased penetration of television and video devices. Consequently, the associated health problems are on the rise. A sedentary lifestyle affects the human body through various mechanisms. Sedentary behaviors reduce lipoprotein lipase activity, muscle glucose, protein transporter activities, impair lipid metabolism, and diminish carbohydrate metabolism. Furthermore, it decreases cardiac output and systemic blood flow while activating the sympathetic nervous system, ultimately reducing insulin sensitivity and vascular function. It also alters the insulin-like growth factor axis and the circulation levels of sex hormones, which elevates the incidence of hormone-related cancers. Increased sedentary time impairs the gravitostat, the body’s weight homeostat, and weight gain, adiposity, and elevated chronic inflammation caused by sedentary behavior are risk factors for cancer. Sedentary behaviors have wide-ranging adverse impacts on the human body including increased all-cause mortality, cardiovascular disease mortality, cancer risk, and risks of metabolic disorders such as diabetes mellitus, hypertension, and dyslipidemia; musculoskeletal disorders such as arthralgia and osteoporosis; depression; and, cognitive impairment. Therefore, reducing sedentary behaviors and increasing physical activity are both important to promote public health.

Relationship Between Prostate Volume and Lower Urinary Tract Symptom in Health Checkup Subjects

Purpose@#This study aimed to evaluate the relationship between prostate volume and lower urinary symptom (LUTS) in subjects undergoing health checkup and to know the usefulness of TRUS in health screening. @*Materials and Methods@#The study was conducted in 883 men aged ≥20 years who underwent TRUS for health screening. All participants had filled in the international prostate symptom score (IPSS) and were tested for prostate-specific antigen; prostate volume, central gland volume, and transitional zone index were measured using TRUS. We analyzed the differences in the IPSS by prostate volume and differences in prostate volume by severity of LUTS and correlation between prostate volume and each component of IPSS. @*Results@#There were differences in the total IPSS, storage score, and voiding score between the subjects with prostate volumes of ≥30 mL or not (p=0.027, p=0.037, and p=0.029, respectively). However, the differences were found only for urgency and weak stream. The volume of the severe symptom group was bigger than those of the mild and moderate symptom groups (p=0.002 and p=0.014). The correlation between prostate volume and IPSS was significant only for the between the central volume and nocturia (r=0.112, p＜0.01). @*Conclusions@#The relationship between prostate volume and urinary symptoms showed significant but low correlation and found only in some components. For the accurate diagnosis, it would be more useful to accompany various voiding-related surveys in addition to TRUS during health screening. (Korean J Urol Oncol 2020;18:53-60)

Physical Activity Patterns and Their Associated Factors Measured by Global Physical Activity Questionnaire Survey among Korean / 대한스포츠의학회지

Research on physical activity and health is actively being conducted. In the Korea National Health and Nutrition Examination Survey (KNHANES), the Global Physical Activity Questionnaire (GPAQ) was newly introduced in 2014. The purpose of this study was to investigate the levels of physical activity and related factors in Koreans who were assessed through the GPAQ by dividing the physical activity by occupation, leisure, and transport domain. This study used data from the KNHANES (2014–2016), the study population of which included 17,357 participants aged 12 to 80 years. We compared the differences in physical activity by sociodemographic factors, health-related factors, and psychological health-related factors. Moreover, we also compared the mean metabolic equivalent of task and daily sitting time according to physical activity domain by sex and age group. Finally, we investigated the sociodemographic factors, health-related factors, and psychological health-related factors that significantly affect the average physical activity per week. The various factors were found to differ in the frequency of physical activity levels. In addition, there was a difference in the amount of physical activity per occupation, leisure, and transport domain in each age group. Finally, age, sex, high-density lipoprotein cholesterol levels, arthritis, allergic rhinitis and sinusitis, sleeping time, and perceived health status significantly affected physical activity. The levels of physical activity significantly differed by sociodemographic factors, health-related factors, and psychological health-related factors. There was also a difference in the physical activity levels according to the age and sex per each domain of physical activity.

Association between Colorectal Adenoma and Hand Grip Strength in the Elderly

BACKGROUND: Obesity is known as an important risk factor for colorectal adenoma. However, for the elderly with changes in body composition, reduced muscle, and increased fat, the body mass index (BMI), one of the most commonly used indicators of obesity, is limited in predicting a link to colorectal cancer. This study aimed to investigate the relationship between colorectal adenoma and grip strength that can predict muscle reduction in the elderly. METHODS: This study included 262 participants aged ≥65 years who underwent medical examination between June 2015 and August 2018. The control group comprised participants with normal findings or hyperplasia and other benign lesions, except adenoma on colonoscopy, whereas the adenoma group consisted of participants with more than one adenoma. Grip strength was alternately measured twice for each hand using a hydraulic dynamometer. RESULTS: The grip strength was statistically lower in the adenoma group than in the control group among women (P=0.042). For both sexes, grip strength was significantly lower in participants with ≥5 adenomas than in those with <5 adenomas (P=0.021, P=0.007). Similarly, men with large adenomas (≥7 mm) exhibited significantly lower grip strength than did those with small adenomas (<7 mm) (P=0.004). Even after correction for age, BMI, smoking status, alcohol consumption, exercise, insulin resistance, hypertension, and diabetes, the negative correlation between grip strength and number of adenomas among men and women remained (P=0.034, P=0.019). CONCLUSIONS: A significant relationship between hand grip strength and number of colorectal adenomas was noted.

Association between Hemoglobin Level and Bone Mineral Density in Korean Adults

BACKGROUND: Low bone mineral density (BMD) increases fracture risk. Anemia is highly prevalent. Some studies suggested that anemia is an independent risk factor for osteoporosis. The aim of this study was to evaluate the association between hemoglobin (Hb) level and BMD in Korean adults. METHODS: This study was based on data from the Korea National Health and Nutrition Examination Survey 2008 to 2011. Propensity score-matching was performed to establish a dataset for analysis. Regression analyses were used to evaluate the association between Hb and BMD. Mean BMD scores were compared between normal and anemia groups, and among normal, anemia with low ferritin, and anemia without low ferritin groups. RESULTS: There were partial positive associations between Hb and BMD in men, but negative associations in women. The normal group had lower mean BMD scores than the anemia group in men. However, the anemia group had higher whole-body and lumbar-spine BMD scores than the normal group in women. In a comparison of the three groups, the anemia without low ferritin group had the lowest all-site BMD scores in men and women. However, the anemia with low ferritin group had the highest all-site BMD scores in women. In postmenopausal women, the anemia without low ferritin group had the lowest all-site BMD scores. In premenopausal women, the anemia with low ferritin group had the highest whole-body BMD scores. CONCLUSIONS: This study found that Hb and anemia status were associated with BMD scores. However, the associations were different according to sex. This may be due to the etiology of anemia or low Hb levels.

The Association between Sitting Time and Health-Related Quality of Life According to Body Mass Index in Elderly Korean

BACKGROUND: Although obesity and health-related quality of life (HRQOL) in elderly are well known to be associated with obesity and sitting time, it is unclear whether effect of sedentary lifestyle on HRQOL is affected by body mass index (BMI) or not. So we analyzed the relationship between sitting time and HRQOL according to BMI groups in elderly Korean. METHODS: Participants aged over 60 from the 6th Korea National Health and Nutrition Examination Survey (2014 and 2015) were included. Participants were classified as normal weight and overweight/obese groups. Mean sitting times were compared between groups according to the EuroQol 5 dimension (EQ-5D) And logistic regression analyses were performed. RESULTS: Men with mobility, usual activity, or pain/discomfort domain problem had longer sitting time. Women with a problem in every domain had longer sitting time. Overweight/obese women with problem showed longer sitting time. Odds ratios (ORs) of mobility, usual activity, pain or discomfort, and low EQ-5D score domain were increased regardless of BMI groups in men. But, ORs of all domains were increased only in overweight/obese group in women. CONCLUSIONS: In elderly Korean, prolonged sitting time associated with decreased HRQOL. Impaired HRQOL is associated with increased sitting time regardless of BMI in men. But only overweight/obese group showed association between prolonged sitting time and impaired HRQOL in women. These results represents that decrease in quality of life according to the increase of the sitting time differs according to the BMI in elderly Korean women.

The Association between Hand Grip Strength and Health-Related Quality of Life in Korean Adults / 대한스포츠의학회지

We investigated the association between hand grip strength (HGS) and health-related quality of life (HRQOL). A total number of 9,211 participants from the sixth Korean National Health and Nutrition Examination Survey (2014– 2015) were included. HRQOL was measured by EuroQol-5 dimension (EQ-5D) and EQ-5D index score. Participants were classified as normal HRQOL group or impaired HRQOL group according to the EQ-5D responses and the EQ-5D index scores. HGS was measured using Takei dynamometer. Impaired HRQOL group represented lower mean HGS than that of normal HRQOL group. According to the quintile groups of HGS, group with the lowest HGS showed the lowest mean EQ-5D index score in both sexes. And the more HGS increases, the more EQ-5D index score increases also (p-value for trend <0.001). Men and women with lower grip strength were more likely to report ‘some’ or ‘extreme problem’ in EQ-5D domains (except anxiety/depression and pain/discomfort domain in men), and also more likely to belong to the lowest 20% level group in EQ-5D index score according to logistic analyses. Our findings suggest that HGS is associated HRQOL. Low HGS is associated with impaired status of HRQOL by EQ-5D and EQ-5D index score in Korean men and women. More research is needed to evaluate the specific plausibility between HGS and HRQOL.