We aimed to investigate how body weight fluctuation affects the risk of developing type 2 diabetes by conducting a nationwide cohort study. A total of 3,855,884 participants from the National Health Insurance System health check-up data from 2012 were included in this study, and follow-up continued until 2016. Body weight was measured at least thrice between 2009 and 2012. Body weight variability (BWV) was estimated using average successive variability (ASV) indices. Cox proportional hazards regression models were used to evaluate the association of BWV with the risk of type 2 diabetes using hazard ratios (HRs) and 95% confidence intervals (CIs). Body weight fluctuation was associated with a higher risk of incident diabetes after adjustment for confounders (HR 1.10, 95% CI 1.07, 1.12 in the highest BWV quartile compared to the lowest). Regardless of the weight change status, the highest ASV quartile of BWV increased the risk for diabetes. Even subjects with a normal glucose tolerance status and those aged under 65 years had a higher risk of diabetes if their body weight highly fluctuated during the follow-up years. Our results suggest that body weight variability is an independent risk factor for diabetes. It is important to pay attention to frequent body weight fluctuations.

An important barrier to smoking-cessation counseling for physicians is a lack of education at the undergraduate level. Interactive methods such as peer role-play (RP) or modules utilizing standardized patients (SPs) may be effective for medical students to enhance their performance on tobacco cessation counseling. This study compared the effectiveness of a module using SPs to that of a RP module for undergraduate medical students on tobacco cessation counseling. This study was conducted over a single week of the family medicine clerkship. One hundred and thirteen fourth-year medical students were randomized into either the SP group or the RP group. A RP module involved a ten-minute encounter between the student doctor and the student patient followed by five minutes of feedback from the observer student using a group developed checklist. In a SP module, each student was asked to interview a SP portraying a smoker with willingness to quit. After the encounter, the SP provided five minutes of direct oral feedback to the student. In both modules, the total intervention lasted three-and-half hours and was supervised by faculty staff. Students’ objective structured clinical examination (OSCE) scores were evaluated to determine their tobacco cessation counseling skills. Four evaluation periods were conducted at baseline, postintervention, post-clerkship, and before receiving the Korean medical licensing examination (KMLE). Students’ smoking knowledge test scores and counseling self-confidence levels at pre- and post-intervention were also compared. In both groups, post-intervention OSCE scores increased significantly compared to baseline (Cohen’s d 0.87, p < 0.001 in SP group; d 0.77, p < 0.001 in RP group). However, there were no differences between the two groups. Students achieved the highest OSCE score for smoking-cessation counseling before the KMLE. After training, student self-confidence and smoking-knowledge test scores increased significantly, regardless of the type of module. Self-confidence was higher in the SP group compared with the RP group (d 0.37, p = 0.01). Peer role-play may be equivalent to the SP method with regard to knowledge and skills reported during smoking-cessation counseling and SP method may be better in self-confidence. Cost and student self-confidence may be important factors when choosing among the teaching methods for smoking-cessation counseling.

Although many studies support the association of obesity with neurodegenerative diseases, such as Parkinson’s disease (PD), there are limited data regarding the association between abdominal obesity and PD, with mixed findings. The aim of this study was to examine the association of waist circumference (WC) with the risk of PD incidence. We retrospectively analyzed a large-scale nationwide cohort of 6,925,646 individuals aged ≥40 years who underwent the Korean National Health Screening during 2009. We performed multivariable Cox proportional hazards regression to evaluate the association of WC and abdominal obesity with PD risk and calculated hazard ratios (HRs) with 95% confidence intervals (CIs) of PD incidence. During a median follow-up period of 8.35 years, 33,300 cases of PD developed. PD incidence was positively associated with increases in WC (P for trend < 0.001). The risk of PD incidence tended to elevate as WC increased (P for trend < 0.001), indicating that the adjusted HRs of PD incidence in the highest WC group versus the reference group was 1.16 (95% CI, 1.10–1.23), whereas it was 0.91 (95% CI 0.84–0.98) in the lowest WC group. Individuals with abdominal obesity were significantly associated with an increased PD risk (HR 1.10, 95% CI: 1.07–1.13). These associations persisted even after adjustment for body mass index and stratification by sex. Even among non-obese individuals, abdominal obesity was associated with a higher PD risk (adjusted HR 1.13, 95% CI: 1.09–1.18). Taken together, higher WC and abdominal obesity were associated with increased PD risk. Even in non-obese individuals, abdominal obesity was associated with an increased PD risk.

Background: Physical activity is known to prevent several diseases and positively affect mental health. Previous studies have shown that smartphone addiction negatively affects the physical activity of children and adolescents. This study aimed to investigate the relationship between problematic smartphone use and physical activity among adolescents and the related factors using path analysis.Methods: Using data from the 16th Youth Risk Behavior Web-based Survey from 2020, scores on the Smartphone Addiction Scale—Short Version for Adolescents, physical activity, sex, socioeconomic status (SES), academic performance, depression, smoking, drinking, and sitting time were assessed. Complex sampling and path analyses were performed.Results: Of the total 54,948 students, 25.5% were smartphone risk users, including potential and high-risk users. The direct path coefficients of each factor indicated that female sex (-0.14 for male), low SES (-0.062), high academic performance (0.056), low sitting time for studying purposes (-0.033), high sitting time for non-studying purposes (0.071), and depressive mood (0.130) were related to problematic smartphone use (all P<0.001). Each factor affected problematic smartphone use, and subsequently had a negative effect on the amount of physical activity, with a direct path coefficient of -0.115 (P<0.001).Conclusion: In this study, we confirmed that problematic smartphone use among adolescents was negatively associated with performing an adequate amount of physical activity and that various factors, such as sex, SES, academic performance, and sitting time, directly and indirectly affected this relationship.

This study was conducted to determine the prevalence of a low appendicular skeletal muscle index (ASMI) using three cut-off points (mean ASMI-2SD of a gender-specific young reference group (aged 18–39 years), mean ASMI-1SD of a gender-specific young reference group, and the lower 20 percentile value of a gender-specific older group (aged ≥ 65 years)) in Korean older people and the relationship between ASMI and subjective health-related quality of life. This study utilized data acquired during the Korean National Health and Nutrition Examination Survey (KNHANES) from 2008–2011. Dual-energy X-ray absorptiometry body compositional data was obtained from a subsample of 6538 subjects (men 2804, women 3734) aged 18–39 and 4413 subjects (men 1872, women 2541) aged 65 years and older. The three definitions of low appendicular skeletal muscle and the EQ-5D-3 L-Korean descriptive system were applied to Korean older people. For the ASMI cutoff points used, in men, the three cutoff points were ASMI 2SD (6.09 kg/m2), ASMI 20 (6.48 kg/m2), and ASMI 1SD (6.95 kg/m2). In women, ASMI 2SD (4.38 kg/m2) was the lowest, followed by ASMI 1SD (4.96 kg/m2) and ASMI 20 (5.33 kg/m2). Proportions of older subjects with a low ASMI using the three cutoff points were 9.7% (ASMI 2SD) and 40.9% (ASMI 1SD) in men, and 0.7% (ASMI 2SD) and 7.4% (ASMI 1SD) in women. By multivariate ordinal logistic regression analysis, men with a low ASMI had significantly high odd ratios for the three domains of mobility (p < 0.001), self-care (p = 0.005), and usual activities (p = 0.004) among the five domains of the EQ-5D and EQ-5D index (p = 0.010). The ASMI 2SD cut-off points for older Koreans, 6.09 kg/m2 for men and 4.38 kg/m2 for women, resulted in low prevalences of a low ASM, that is, 9.7% for men and 0.7% for women, and showed low clinical usefulness due to very low determined prevalence in women. Hence, we suggest that the cut-off point of the lowest 20% of Korean older people (men: 6.48 kg/m2, women; 5.33 kg/m2) be used for older Koreans.

Chang HA, et al. Korean J Fam Med. 2010 Aug;31(8):600-606. http://dx.doi.org/10.4082/kjfm.2010.31.8.600