Background Online misinformation proliferation during the COVID-19 pandemic has become a major public health concern. Objective We aimed to assess the prevalence of COVID-19 misinformation exposure and beliefs, associated factors including psychological distress with misinformation exposure, and the associations between COVID-19 knowledge and number of preventive behaviors. Methods A cross-sectional online survey was conducted with 1049 South Korean adults in April 2020. Respondents were asked about receiving COVID-19 misinformation using 12 items identified by the World Health Organization. Logistic regression was used to compute adjusted odds ratios (aORs) for the association of receiving misinformation with sociodemographic characteristics, source of information, COVID-19 misinformation belief, and psychological distress, as well as the associations of COVID-19 misinformation belief with COVID-19 knowledge and the number of COVID-19 preventive behaviors among those who received the misinformation. All data were weighted according to the Korea census data in 2018. Results Overall, 67.78% (n=711) of respondents reported exposure to at least one COVID-19 misinformation item. Misinformation exposure was associated with younger age, higher education levels, and lower income. Sources of information associated with misinformation exposure were social networking services (aOR 1.67, 95% CI 1.20-2.32) and instant messaging (aOR 1.79, 1.27-2.51). Misinformation exposure was also associated with psychological distress including anxiety (aOR 1.80, 1.24-2.61), depressive (aOR 1.47, 1.09-2.00), and posttraumatic stress disorder symptoms (aOR 1.97, 1.42-2.73), as well as misinformation belief (aOR 7.33, 5.17-10.38). Misinformation belief was associated with poorer COVID-19 knowledge (high: aOR 0.62, 0.45-0.84) and fewer preventive behaviors (≥7 behaviors: aOR 0.54, 0.39-0.74). Conclusions COVID-19 misinformation exposure was associated with misinformation belief, while misinformation belief was associated with fewer preventive behaviors. Given the potential of misinformation to undermine global efforts in COVID-19 disease control, up-to-date public health strategies are required to counter the proliferation of misinformation.

We investigated the prevalence of dementia and mild cognitive impairment (MCI) and the factors associate with risk of dementia from a representative nationwide sample of Korean elders. 8,199 randomly-sampled Koreans aged 65 years or older were invited to participate in the Phase I screening assessment using Mini-Mental State Examination by door-to-door home visit, and 6,141 subjects (response rate = 74.9%) responded. Among them, 2,336 subjects were invited to participate in the Phase II diagnostic assessment for dementia and MCI, and 1,673 subjects responded (response rate = 71.6%). Diagnostic assessments were administered using the Korean version of the Consortium to Establish a Registry for Alzheimer's Disease Assessment Packet (CERAD-K) Clinical Assessment Battery. The CERAD-K Neuropsychological Assessment Battery was used for diagnosing MCI. Age-, gender-, education-, and urbanicity-standardized prevalence of dementia was estimated to be 8.1% (95% CI = 6.9-9.2) for overall dementia and 24.1% (95% CI = 21.0-27.2) for MCI. Alzheimer's disease (AD) was the most prevalent type (5.7%) followed by vascular dementia (2.0%). Amnestic subtype (20.1%) was much more prevalent than nonamnestic subtype in MCI (4.0%). Older age, being male, lower education level, illiteracy, smoking, and histories of head trauma or depression were associated with increased dementia risk, and alcohol use and moderately intense exercise were associated with decreased dementia risk. We expect numbers of dementia patients to double every 20 years until 2050 in Korea and expect AD to account for progressively more dementia cases in the future.

ObjectiveThe relationship among chronic fatigue, depressive symptoms, and post-traumatic stress symptoms (PTSSs) among Middle East respiratory syndrome (MERS) survivors is poorly understood. MethodsOf 148 survivors who consented to be registered and underwent assessments at 12 months (T1) and 18 months (T2) after the MERS outbreak, 72 (48.65%) were evaluated for chronic fatigue, depressive symptoms, and PTSSs based on the Impact of Event ScaleRevised (IES-R), the Patient Health Questionnaire-9 (PHQ-9), and the Fatigue Severity Scale (FSS). Data from 52 subjects, who completed both assessments, were analyzed using a regression-based serial multiple mediation model (PROCESS Model 6). ResultsBootstrap analyses indicated no direct effects of T1 FSS on T2 IES-R but significant positive indirect effects of T1 FSS on T2 IESR through T1 PHQ-9 and T2 PHQ-9 (B=2.1601, SE=1.3268, 95% confidence interval=0.4250–6.1307). In other words, both T1 PHQ-9 and T2 PHQ-9 fully mediated the relationship between T1 FSS and T2 IES. ConclusionChronic fatigue 12 months after MERS had indirect effects on prolonged PTSSs 18 months after MERS via persisting depression in MERS survivors. This finding supports the need to promote interventional programs for emerging infectious disease survivors with chronic fatigue to reduce depression and prevent prolonged PTSSs.

Depression was associated with DED symptoms in subjects with normal or mildly reduced tear production.

This study indicates that the assessment and management of coexisting depression should be integrated with the assessment and management of knee osteoarthritis, particularly when radiographic changes of osteoarthritis in the knee joint are not severe.

To evaluate the prevalence of and risk factors for dry eye disease (DED) in an elderly Korean population.Methods: This population-based study in Yongin, Korea, included 657 individuals 65 years or older randomly selected from an official household registration database. Dry eye symptoms were assessed using a 6-item questionnaire, and DED was defined as having 1 or more dry eye symptoms often or all the time. Dry eye tests, including the Schirmer test, tear film break-up time measured using fluorescein, cornea fluorescein staining, and examination for meibomian gland dysfunction, were performed. Results:The crude prevalence of DED was 30.3%, and the age-, sex-, and region (urban vs rural)-adjusted preva-lence was 33.2%. Women (P=.01) and urban dwellers (P =.001) were more likely to have DED. Of those with DED, 85.1% had tear film break-up time of 10 seconds or less, 54.1% had meibomian gland dysfunction, 39.2% had a fluorescein score of 1 or greater, and 32.8% had a Schirmer test score of 5 mm or less. A low Schirmer score was correlated with increased prevalence of DED, although sensitivity was low.Conclusions: Dry eye disease is common in elderly Koreans; female sex and living in an urban region were strongly correlated with its frequency. We also noted a positive correlation between low Schirmer test scores and symptom-based DED.

The number of impaired cognitive domains, but not the presence of memory impairment, predicted poor outcomes in people with MCI. However, MCI subtype was diagnostically unstable.

Cyclohexane-1,4-dimethanol/DMC Condensation Polymerization. The first step was conducted with cyclohexane-1,4-dimethanol (10.0 g, 69 mmol, a mixture of cisand transisomers in 3:7 ratio), NaH (3.3 mg, 0.14 mmol) and DMC (10.3 g, 114 mmol), using identical conditions and procedures to those used for DB/DMC condensation polymerization. In the second step, the condensation reaction was conducted at 180 °C and 380 mmHg for 1 h, at 210 °C and 0.3 mmHg for 1 h, and finally at 240 °C and 0.3 mmHg for 3 h. The catalyst was neutralized with phthaloyl dichloride using the same procedures and conditions as those used for DB/DMC condensation polymerization. 1 H NMR (CDCl 3 ):  4.04 (d, J = 7.2 Hz, 1.2H, 2 CH 2 OC(O) in cis-isomer), 3.94 (d, J = 6.4 Hz, 2.8H, CH 2 OC(O) in trans-isomer), 2.10-0.80 (m, 10H) ppm.