Size-Specific Dose Estimation In the Korean Lung Cancer Screening Project: Does a 32-cm Diameter Phantom Represent a Standard-Sized Patient in Korean Population?

OBJECTIVE: The purposes of this study were to evaluate size-specific dose estimate (SSDE) of low-dose CT (LDCT) in the Korean Lung Cancer Screening (K-LUCAS) project and to determine whether CT protocols from Western countries are appropriate for lung cancer screening in Korea. MATERIALS AND METHODS: For participants (n = 256, four institutions) of K-LUCAS pilot study, volume CT dose index (CTDI(vol)) using a 32-cm diameter reference phantom was compared with SSDE, which was recalculated from CTDI(vol) using size-dependent conversion factor (f-size) based on the body size, as described in the American Association of Physicists in Medicine Report 204. This comparison was subsequently assessed by body mass index (BMI) levels (underweight/normal vs. overweight/obese), and automatic exposure control (AEC) adaptation (yes/no). RESULTS: Size-specific dose estimate was higher than CTDI(vol) (2.22 ± 0.75 mGy vs. 1.67 ± 0.60 mGy, p < 0.001), since the f-size was larger than 1.0 for all participants. The ratio of SSDE to CTDI(vol) was higher in lower BMI groups; 1.26, 1.37, 1.43, and 1.53 in the obese (n = 103), overweight (n = 70), normal (n = 75), and underweight (n = 4), respectively. The ratio of SSDE to CTDI(vol) was greater in standard-sized participants than in large-sized participants independent of AEC adaptation; with AEC, SSDE/CTDI(vol) in large- vs. standard-sized participants: 1.30 ± 0.08 vs. 1.44 ± 0.08 (p < 0.001) and without AEC, 1.32 ± 0.08 vs. 1.42 ± 0.06 (p < 0.001). CONCLUSION: Volume CT dose index based on a reference phantom underestimates radiation exposure of LDCT in standard-sized Korean participants. The optimal radiation dose limit needs to be verified for standard-sized Korean participants.

Effect of Coffee Consumption on the Progression of Type 2 Diabetes Mellitus among Prediabetic Individuals / 가정의학회지

BACKGROUND: A previous large-scale cohort study investigated the relationship between coffee intake and the progression of diabetes mellitus in the United States. However, studies on the effects of coffee on diabetes are rare in South Korea. Therefore, this study assessed the amount and method of coffee intake in Koreans in order to determine if coffee intake has a prophylactic effect on diabetes progression. METHODS: This study included 3,497 prediabetic patients from a single medical institution, with glycated hemoglobin levels ranging from 5.7% to 6.4%. Cross-tabulation and Kaplan-Meier survival analyses were performed to compare patients with and without diabetes progression based on the frequency and method of coffee intake. Cox proportional hazard analysis was performed to correct for confounding variables. RESULTS: The observation period (mean+/-standard deviation) was 3.7+/-2.3 years. Kaplan-Meier survival analysis revealed that the risk of diabetes progression was lowest in patients who drank black coffee three or more times per day (P=0.036). However, correction for confounding variables in Cox proportional hazard analysis revealed that, while the risk was lower for the patients who typically consumed black coffee than for those who mixed creamer and sugar into their coffees, the difference was not significant. CONCLUSION: The results of this study suggest that drinking coffee without sugar and creamer at least three times daily has the greatest preventive effect on diabetes onset.

The Effects of Alcohol on Quality of Sleep / 가정의학회지

BACKGROUND: Alcohol is traditionally known to have a relaxing effect. However, persons who consume alcohol in excessive amounts suffer from poor sleep quality and patients with alcohol use disorders commonly report insomnia. In this study, we aimed to evaluate the effects of alcohol use on sleep quality. METHODS: A questionnaire-based cross-sectional survey was conducted with 234 men and 159 women who had visited a general hospital. We used structured questionnaires, including Alcohol Use Disorder Identification Test-Korean revised version (AUDIT-KR) and the Pittsburgh Sleep Quality Index-Korean version (PSQI-K). We analyzed the association between scores for all subcategories of the PSQI-K and the AUDIT-KR and then analyzed the correlation between AUDIT-KR and global PSQI-K scores. RESULTS: The global PSQI-K score for men was positively correlated with the AUDIT-KR score (P=0.008) after adjusting for age, chronic disease, tobacco use, exercise, depression, and anxiety. The AUDIT-KR score was significantly associated with subjective sleep quality (P=0.005), sleep duration (P=0.047), and sleep disturbance (P=0.048); it was not associated with sleep latency, sleep efficiency, or daytime dysfunction. Sleep disturbances due to snoring were significantly associated with total AUDIT-KR score (P=0.008). There was no correlation between the global PSQI-K and AUDIT-KR scores for women (P=0.333). However, daytime dysfunction showed a significant association with total AUDIT-KR score (P=0.048). CONCLUSION: Men with higher AUDIT-KR scores tended to suffer from poor sleep quality. AUDIT-KR scores showed significant correlations with subjective sleep quality, sleep duration, and sleep disturbances in men.

The Relationship Between the Social Network of Community-living Elders and Their Health-related Quality of Life in Korean Province / 예방의학회지

OBJECTIVES: This study aimed to collect information that will help enhance the social networks and improve the quality of life among elderly people by observing the relationship between their social network and health-related quality of life (HRQoL) and by analyzing social network factors affecting HRQoL. METHODS: This study was based on the 2008 Community Health Survey in Yeoncheon County. Three hundred elders were included in the study population. We compared the revised Lubben Social Network Scale (LSNS-R) score and Euro quality of life-5 dimensions health status index by demographic characteristics and chronic disease prevalence. We analyzed the data using multiple regression and tobit regression by setting the HRQoL as the dependent variable and social network and other characteristics as the independent variables. We analyzed social network factors by using factor analysis. RESULTS: The LSNS-R score differed significantly according to age and existence of a spouse. According to the results from the hierarchical multiple regression analysis, the LSNS-R explained 0.10 of the variance and LSNS-R friends factor explained 0.10 of the variance. The tobit regression indicated that the contribution of the LSNS-R family size factor to the regression coefficient of the independent variable that affected the HRQoL was BT=2.96, that of the LSNS-R family frequency factor was BT=3.60, and that of LSNS-R friends factor was BT=5.41. CONCLUSIONS: Social networks among elderly people had a significant effect on HRQoL and their networks of friends had a relatively higher effect than those of family members.

Factors Affecting Public Prejudice and Social Distance on Mental Illness: Analysis of Contextual Effect by Multi-level Analysis / 예방의학회지

OBJECTIVES: While there have been many quantitative studies on the public's attitude towards mental illnesses, it is hard to find quantitative study which focused on the contextual effect on the public's attitude. The purpose of this study was to identify factors that affect the public's beliefs and attitudes including contextual effects. METHODS: We analyzed survey on the public's beliefs and attitudes towards mental illness in Korea with multi-level analysis. We analyzed the public's beliefs and attitudes in terms of prejudice as an intermediate outcome and social distance as a final outcome. Then, we focused on the associations of factors, which were individual and regional socio-economic factors, familiarity, and knowledge based on the comparison of the intermediate and final outcomes. RESULTS: Prejudice was not explained by regional variables but was only correlated with individual factors. Prejudice increased with age and decreased by high education level. However, social distance controlling for prejudice increased in females, in people with a high education level, and in regions with a high education level and a high proportion of the old. Therefore, social distance without controlling for prejudice increased in females, in the elderly, in highly educated people, and in regions with a high education and aged community. CONCLUSIONS: The result of the multi-level analysis for the regional variables suggests that social distance for mental illness are not only determined by individual factors but also influenced by the surroundings so that it could be tackled sufficiently with appropriate considering of the relevant regional context with individual characteristics.