BACKGROUND/AIMS: To identify the factors associated with time to diagnosis after symptom onset in patients with early rheumatoid arthritis (RA). METHODS: Early RA patients with ≤ 1 year of disease duration in the KORean Observational study Network for Arthritis (KORONA) database were included in this analysis. Patients were further divided into two groups according to the time to diagnosis from symptom onset: the early diagnosis group (time to diagnosis ≤ 1 year) and the late diagnosis group (time to diagnosis > 1 year). Using the multivariable regression model, we identified factors associated with early diagnosis. RESULTS: Among 714 early RA patients, 401 patients (56.2%) and 313 patients (43.8%) were included in the early diagnosis and late diagnosis groups, respectively. The mean disease duration was 0.47 years in the early diagnosis group and 0.45 years in the late diagnosis group. In multivariable model analysis, greater age at onset (odds ratio [OR], 1.03; 95% confidence interval [CI], 1.02 to 1.05), high school education or higher (OR, 1.68; 95% CI, 1.14 to 2.47), higher income (OR, 1.48; 95% CI, 1.05 to 2.08), and initial small joint involvement (OR, 1.42; 95% CI, 1.02 to 1.98) were factors associated with early diagnosis. At diagnosis, disease activity scores using 28 joints on diagnosis (3.81 ± 1.44 vs. 3.82 ± 1.42, p = 0.92) and functional disability (0.65 ± 0.61 vs. 0.57 ± 0.62, p = 0.07) did not different between the two groups. However, hand joint erosion on X-ray (37.8% vs. 25.6%, p < 0.01) was more common in the late diagnosis group than the early diagnosis group. CONCLUSIONS Older onset age, higher educational level and income, and initial small joint involvement were positive factors for early diagnosis of RA.

BACKGROUND: Rheumatoid arthritis (RA) treatment may differ according to hepatitis B state and consequently may bring about different arthritis outcomes. However, whether hepatitis B affects treatment outcome remains unclear. We investigated differences in change in arthritis activity between RA patients according to concomitant hepatitis B virus infection. METHODS: A retrospective medical chart review was performed by two rheumatologic fellows using single center data, from January 2000 to March 2015. Among RA patients older than 18 years, patients with comorbidities that could affect RA treatment aside from hepatitis B were excluded. Using 1:3 propensity score matching, 40 hepatitis B virus surface antigen (HBsAg)-positive patients and 112 HBsAg-negative patients were included in the study. Data were collected longitudinally using standardized electronic forms. The longitudinal relationship between HBsAg-positivity and RA activity was analyzed using generalized estimating equations. RESULTS: RA activity showed time-dependent improvement. Reductions of swollen joint count over time were significantly larger in the HBsAg-negative group. However, changes in disease activity score in 28 joints with three variables (DAS28-3), tender joint count, erythrocyte sedimentation rate and C-reactive protein level did not differ between the groups. There were no differences in alanine aminotransferase level. HBsAg-positive patients were less likely to receive methotrexate (odds ratio [OR], 0.09; 95% confidence interval [CI], 0.04–0.19; P < 0.001) and more likely to receive sulfasalazine (OR, 3.67; 95% CI, 1.94–6.95; P < 0.001). CONCLUSION: RA medication use varied according to HBsAg-positivity. However, improvement in RA activity was not significantly affected by concomitant hepatitis B infection.
Alanine Transaminase ; Antigens, Surface ; Arthritis* ; Arthritis, Rheumatoid* ; C-Reactive Protein ; Comorbidity ; Erythrocyte Count ; Hepatitis B virus ; Hepatitis B* ; Hepatitis* ; Humans ; Joints ; Methotrexate ; Propensity Score ; Retrospective Studies* ; Sulfasalazine ; Treatment Outcome

OBJECTIVE: To estimate the prevalence of non-adherence to rheumatoid arthritis (RA) medication and identify the associated factors for non-adherence in RA patients. METHODS: Among the KORean Observational study Network for Arthritis 3,523 patients who completed a questionnaire about the adherence to RA medication were analyzed. The patients were divided into two groups: 1) adherent group, patients who skipped medication ≤5 days within the past 2 months; and 2) non-adherent group, patients who skipped ≥6 days of medication. The baseline characteristics were compared, and multivariable regression analysis was performed to identify the associated factors for non-adherence. RESULTS: The non-adherent group had 339 patients (9.6%). The common causes of non-adherence were forgetfulness (45.8%), absence of RA symptoms (24.7%), and discomfort with RA medication (13.1%). Younger age (odds ratio [OR] 1.02, p < 0.01) and higher income (OR 1.70, p < 0.01) were associated with an increased risk of non-adherence. Whereas higher functional disability (OR 0.68, p < 0.01) and oral corticosteroid use (OR 0.73, p=0.02) were associated with a decreased risk of non-adherence. The associated factors differed according to cause of non-adherence. Having adverse events (OR 2.65, p=0.02) was associated with the risk of non-adherence due to discomfort with RA medication while a higher level of education (OR 2.37, p=0.03) was associated with the risk of non-adherence due to an absence of RA symptoms. CONCLUSION: The 9.6% of Korean RA patients were non-adherent to RA medication. The associated factors differed according to the cause of non-adherence. Therefore, an individualized approach will be needed to improve the adherence to RA medication.
Arthritis ; Arthritis, Rheumatoid ; Education ; Humans ; Medication Adherence ; Observational Study ; Prevalence

BACKGROUND/AIMS: To determine whether early diagnosis is beneficial for functional status of various disease durations in rheumatoid arthritis (RA) patients. METHODS: A total of 4,540 RA patients were enrolled as part of the Korean Observational Study Network for Arthritis (KORONA). We defined early diagnosis as a lag time between symptom onset and RA diagnosis of ≤ 12 months, whereas patients with a longer lag time comprised the delayed diagnosis group. Demographic characteristics and outcomes were compared between early and delayed diagnosis groups. Logistic regression analyses were performed to identify the impact of early diagnosis on the development of functional disability in RA patients. RESULTS: A total of 2,597 patients (57.2%) were included in the early diagnosis group. The average Health Assessment Questionnaire-Disability Index (HAQ-DI) score was higher in the delayed diagnosis group (0.64 ± 0.63 vs. 0.70 ± 0.66, p < 0.01), and the proportion of patients with no functional disability (HAQ = 0) was higher in the early diagnosis group (22.9% vs. 20.0%, p = 0.02). In multivariable analyses, early diagnosis was independently associated with no functional disability (odds ratio [OR], 1.19; 95% confidence interval [CI], 1.01 to 1.40). In a subgroup analysis according to disease duration, early diagnosis was associated with no functional disability in patients with disease duration < 5 years (OR, 1.37; 95% CI, 1.09 to 1.72) but not in patients with longer disease duration (for 5 to 10 years: OR, 1.07; 95% CI, 0.75 to 1.52; for ≥ 10 years: OR, 0.92; 95% CI, 0.65 to 1.28). CONCLUSIONS: Early diagnosis is associated with no functional disability, especially in patients with shorter disease duration.
Arthritis ; Arthritis, Rheumatoid* ; Delayed Diagnosis ; Diagnosis ; Early Diagnosis* ; Humans ; Logistic Models ; Observational Study

This study aimed to evaluate the frequency and clinical characteristics of hydroxychloroquine (HCQ) retinopathy in Korean patients with rheumatologic diseases. We retrospectively reviewed medical records of 310 patients taking HCQ. Ophthalmic examinations included spectral-domain optical coherence tomography (SD-OCT), automated visual field test, and fundus autofluorescence. The severity of retinopathy was categorized as early, moderate, or severe, and the location was categorized as parafoveal, pericentral, or mixed pattern. Among 310 patients, 9 patients (2.9%) were diagnosed as HCQ retinopathy. Among the patients with HCQ use ≥ 5 years (n = 174), the frequency was 5.2%. Only 1 (11.1%) of the 9 patients was symptomatic. The mean daily dose per kilogram of real body weight of the 9 patients was 5.6 mg, and only 3 had used 6.5 mg or more. Four of the 9 patients had severe HCQ retinopathy. Six of the 9 patients showed pericentral or mixed pattern of retinal damage. Consequently, the frequency of HCQ retinopathy in Korean patients was not low, especially when administered at a high cumulative dose and for a long duration. Screening of HCQ retinopathy by the recommended guidelines that include SD-OCT seems useful and should be done to detect retinal damage earlier in patients with chronic exposure to HCQ.
Body Weight ; Humans ; Hydroxychloroquine* ; Mass Screening ; Medical Records ; Retinaldehyde ; Retrospective Studies ; Tomography, Optical Coherence ; Visual Field Tests

Remission is a primary end point of in clinical practice and trials of treatments for rheumatoid arthritis (RA). The 2011 American College of Rheumatology/European League Against Rheumatism (ACR/EULAR) remission criteria were developed to provide a consensus definition of remission. This study aimed to assess the concordance between the new remission criteria and the physician’s clinical judgment of remission and also to identify factors that affect the discordance between these two approaches. A total of 3,209 patients with RA were included from the KORean Observational Study Network for Arthritis (KORONA) database. The frequency of remission was evaluated based on each approach. The agreement between the results was estimated by Cohen's kappa (κ). Patients with remission according to the 2011 ACR/EULAR criteria (i.e. the Boolean criteria) and/or physician judgment (n = 855) were divided into three groups: concordant remission, the Boolean criteria only, and physician judgment only. Multinomial logistic regression analysis was used to identify factors responsible for the assignment of patients with remission to one of the discordant groups rather than the concordant group. The remission rates using the Boolean criteria and physician judgment were 10.5% and 19.9%, respectively. The agreement between two approaches for remission was low (κ = 0.226) and the concordant remission rate was only 5.5% (n = 177). Pain affected classification in both discordant groups, whereas fatigue was associated with remission only by physician clinical judgment. The Boolean criteria were more stringent than clinical judgment. Patient subjective symptoms such as pain and fatigue were associated with discordance between the two approaches.
Arthritis ; Arthritis, Rheumatoid* ; Classification ; Consensus ; Fatigue ; Humans ; Judgment* ; Logistic Models ; Observational Study ; Rheumatic Diseases

Previous Korean total diet studies (KTDSs) have estimated dietary exposure to toxic chemicals based on 110-120 representative foods selected from over 500 foods appeared in the Korea National Health & Nutrition Examination Surveys (KNHANES), which would result in a possible underestimation. In order to find measures for a closer-to-real estimate of dietary exposure to heavy metals, this study examined the feasibility of mapping foods to the representative foods in the KTDS by comparing estimates. In mapping, those foods not analyzed in the 2009 KTDS (443 out of 559 foods appeared in the 2007 KNHANES) were mapped to the 114 representative foods used in the 2009 KTDS based on the closeness in regards to biological systematics and morphological similarity. Dietary exposures to total mercury and lead were re-estimated using the content of total mercury and lead in 114 foods analyzed in the 2009 KTDS, food intake, and individual's own body weight for respondents in the 2007 KNHANES instead of mean body weight of Koreans used in the 2009 KTDS. The re-estimates of exposure with mapping were approximately 50% higher than the original estimates reported in the 2009 KTDS. In addition, mapping enabled the comparison of percentile distribution of the exposure among populations of different age groups. In conclusion, estimates via mapping resulted in a more comprehensive estimation of dietary exposure to heavy metals present in foods that Koreans consume.
Body Weight ; Surveys and Questionnaires ; Diet ; Eating ; Humans ; Korea ; Metals, Heavy

It is well established that excessive sodium intake is related to a higher incidence of chronic diseases such as hypertension, stroke, coronary heart disease, cardiovascular disease and gastric cancer. Although the upper limit of the current sodium intake guideline by WHO is set at 2,000 mg/day for adults, sodium intake of Koreans is well over 4,700 mg/capita/day implying an urgent need to develop and implement sodium intake reduction policy at the national level. This study investigated the cost-effectiveness of the sodium intake reduction policy, for the first time, in Korea. Analyses were performed using most recent and representative data on national health insurance statistics, healthcare utilization, employment information, disease morbidity/mortality, etc. The socioeconomic benefits of the policy, resulting from reduced morbidity of those relevant diseases, included lower medical expenditures, transportation costs, caregiver cost for inpatients and income losses. The socioeconomic benefits from diminished mortality included reductions in earning losses and welfare losses caused by early deaths. It is estimated that the amount of total benefits of reducing sodium intake from 4.7 g to 3.0 g is 12.6 trillion Korean Won; and the size of its cost is 149 billion Won. Assuming that the effect of sodium intake reduction would become gradually evident over a 5-year period, the implied rate of average return to the sodium reduction policy is 7,790% for the following 25 years, suggesting a very high cost-effectiveness. Accordingly, development and implementation of a mid-to-long term plan for a consistent sodium intake reduction policy is extremely beneficial and well warranted.
Adult ; Cardiovascular Diseases ; Caregivers ; Chronic Disease ; Coronary Disease ; Cost-Benefit Analysis ; Delivery of Health Care ; Employment ; Health Expenditures ; Humans ; Hypertension ; Incidence ; Inpatients ; Korea ; National Health Programs ; Sodium ; Stomach Neoplasms ; Stroke ; Transportation

With a recent increase in dietary supplements (DS) consumption among children in Korea, this study was performed to examine the influencing factors on children's DS consumption. A nationwide survey was conducted employing 3 representative samples of children for summer & fall of 2008 and spring of 2009 by stratified multistage sampling of 120 survey sites per season based on the 2005 census population. Approximately 30 households from each survey site were screened for residing children of 0-19 years and about 1,700 households remained as eligible samples per season. Trained dietitians visited households to perform face-to-face interview to children and/or parents regarding DS consumption including health functional foods (HFF), vitamins/minerals (V/M) supplements and other food supplements during 1 month prior to interview. Out of 5,328 children responded, 18.7% reported DS consumption. Consumption rate was higher in boys (19.9% vs. 17.3% in girls, P < 0.05) and youngsters (22.8% compared to 15.0% in adolescents, P < 0.001). Children from higher income family (P < 0.001), those living in apartments (P < 0.001), those residing in metropolitan area (P < 0.001), and those of mothers with higher education (P < 0.001) were more likely to take DS. Also, mother's employment status and occupation were significantly associated with children's DS consumption. The most popular DS was HFF (72.1%), which was consumed more in children of higher income family. It is revealed that socioeconomic factors affect children's DS consumption significantly. Also it is necessary to estimate children's V/M intake from DS and foods together especially because there are tolerable upper limits set for V/M for safety purposes.
Adolescent ; Censuses ; Child ; Dietary Supplements ; Employment ; Family Characteristics ; Functional Food ; Humans ; Korea ; Mothers ; Occupations ; Parents ; Seasons ; Socioeconomic Factors

We attempted to define the sources of sodium intake for the Korean population at prepared dish level to provide a basis for developing sustainable nutrition policies and feasible programs for sodium intake reduction. Dietary intake data from 2008 and 2009 Korea National Health and Nutrition Examination Survey was used in the analysis for sodium intake sources. Sodium intake from individual dish consumed by each subject was calculated and used in delineating major sodium sources at dish and dish group level for sub-populations of different sex and age. Also, sodium intake was compared between eaters and non-eaters of some specific dish groups with considerable contribution to total sodium intake. The number of subjects included in the analysis was 18,022 and mean sodium intake was 4,600 mg/capita/day. Major sources of sodium intake at dish group level were in the following order: kimchi (1125 mg, 24.5%), noodles (572 mg, 12.4%), soups (488 mg, 10.6%), stews (399 mg, 8.7%), and cooked rice (284 mg, 6.2%). The magnitude of contribution to total sodium intake by soups and stews was different by age group. Sodium intake difference between eaters and non-eaters was much larger for kimchi group (2,343 mg for male, 1,452 mg for female) than for soups or stews. Interaction between consumption of aforementioned specific dish groups and age was highly significant (p < 0.0005) for both sexes. This study revealed an importance of having not only the control over sodium content of foods/dishes, but also the customized approach for different groups of population to accomplish an appreciable reduction in sodium intake.
Humans ; Korea ; Male ; Nutrition Policy ; Nutrition Surveys ; Sodium