Healthy Korean Research Articles

The association of the Korean Healthy Eating Index with chronic conditions in middle-aged single-person households.

This study investigated the association between dietary quality based on the Korean Healthy Eating Index (KHEI), and the prevalence of chronic conditions among middle-aged individuals (40-60 ys of age) living alone. The participants were selected (1,517 men and 2,596 women) from the Korea National Health and Nutrition Examination Survey (KNHANES) 2016-2018 and classified into single-person households (SPH) and multi-person households (MPH). Nutrient intake, KHEI, and the prevalence of chronic conditions were compared according to household size. The odds ratios (ORs) of chronic conditions were analyzed according to the tertile levels of KHEI by gender within each household size category. Men in SPH had a significantly lower total KHEI score (P < 0.0001) and a lower prevalence of obesity (OR, 0.576) than those in MPH. For men, the adjusted ORs for obesity, hypertension, and hypertriglyceridemia in the first tertile (T1) of KHEI scores within SPH compared with the third tertile (T3) were 4.625, 3.790, and 4.333, respectively. Moreover, the adjusted OR for hypertriglyceridemia in the T1 group compared to the T3 group within the MPH was 1.556. For women, the adjusted ORs for obesity and hypertriglyceridemia in T1 compared to T3 within the SPH were 3.223 and 7.134, respectively, and 1.573 and 1.373 for obesity and hypertension, respectively, within MPH. A healthy eating index was associated with a reduced risk of chronic conditions in middle-aged adults. Greater adherence to a healthy eating index could lower the risk of chronic conditions in middle-aged adults living alone.

Prevalence, Distribution, and Concomitance of Whole-Spine Ossification of the Posterior Longitudinal Ligament and Ossification of the Ligament Flavum in South Koreans: A Whole-Spine-CT-Based Cross-Sectional Study.

No studies assessing the prevalence of ossification of the spinal ligament were conducted using whole-spine positron emission tomography and computed tomography (PET-CT) in healthy Koreans. We aimed to determine the prevalence of ossification of the posterior longitudinal ligament (OPLL) and ossification of the ligament flavum (OLF) in healthy Koreans using whole-body PET-CT. We reviewed whole-body PET-CT images captured during general health checkups at the General Health Promotion Center of our institution from January 2015 to 2020. OPLL and OLF were identified by the presence of heterotopic ossification in the posterior longitudinal ligament and ligament flavum on axial and sagittal PET-CT images. A total of 1,934 adults (1,645 men, 289 women) were included. The mean age was 48.05 years (range, 28-86 years). Among the 1,934 patients, 173 had OPLL (8.9%). The most commonly involved cervical vertebra levels arranged according to frequency were C4, C5, C3, and C6. OLF was observed in 125 patients (6.5%). The most commonly involved thoracic levels were T10, T11, and T5. The prevalence of OPLL and OLF was the highest in patients aged 60-69 years. Among the C-OPLL patients, 15.1% had T-OPLL, 5.0% had L-OPLL, and 25.8% had T-OLF. Our study revealed the prevalence of OPLL and OLF in healthy Korean subjects. It was consistent with that in other Asian countries. The presence of OPLL and OLF at most locations correlated with the presence or absence of spinal ossification at other locations.

Speech handicap and vocal tract discomfort with different types of face masks in the COVID-19 era

Purpose: Compulsory use of masks is recommended to prevent droplet infection during the COVID-19 pandemic. This can alter optimal communication in daily life. This study compared the self-perceived speech handicap and vocal tract discomfort when wearing and not wearing a face mask and different types of face masks in a healthy population.Methods: This is a cross-sectional study conducted via an online questionnaire. Speech Handicap Index (SHI) and Vocal Tract Discomfort Scale (VTDS) scores were collected via Google forms (Google, Mountain View, California) from 128 healthy Korean populations with and without face masks and different types of face masks.Results: While speaking with a face mask, subjects were identified with a significant lack of air, unclear articulation, and reduced speech intelligibility in a noisy situation. Although total SHI and VTDS scores exhibited slightly higher with a face mask, no significant differences were found between with and without mask conditions. For mask type, individuals who frequently wore KF94 masks subjectively perceived significantly higher speech handicap and vocal tract discomfort than surgical or fabric masks.Conclusions: In the current study, wearing a face mask did not have a significant impact on speech handicap and vocal tract discomfort in a healthy adult population during the COVID-19 pandemic period, implying people already adapted to wearing a face mask. In terms of speech problems and frequency, the severity of sensation or symptoms of vocal discomfort significantly differed depending on which face mask type they used. Future research should address self-evaluation of their feeling or experience due to face mask use, considering the elderly and patients with communication disorders who suffer more with communication in daily life.

Pharmacokinetics, safety and tolerability of valbenazine in Korean CYP2D6 normal and intermediate metabolizers.

Valbenazine is a selective vesicular monoamine transporter 2 (VMAT2) inhibitor approved for tardive dyskinesia treatment by the US Food and Drug Administration; its major active metabolite (NBI-98782) is a 45-fold more potent inhibitor of VMAT2 than the parent drug. This study aimed to evaluate the pharmacokinetics (PKs), safety, and tolerability and the effect of cytochrome P450 2D6 (CYP2D6) genotypes to the PKs after the administration of valbenazine in Korean participants. A randomized, double-blind, placebo-controlled, single- and multiple-dose study was conducted in healthy Korean male participants. The single-dose study was conducted for both 40 and 80 mg valbenazine and the multiple dose study was conducted for 40 mg. After a 1-week washout, the 40 mg dose group participants received valbenazine 40 mg or placebo once daily for 8 days. Serial blood samples were collected up to 96 h postdose for PK analysis. The CYP2D6 genotypes of the participants were retrospectively analyzed. A total of 50 participants were randomized, and 43 and 20 participants completed the single- and multiple-dose phases of the study, respectively. After single doses, the PK characteristics of valbenazine and its metabolites were similar between the 40 and 80 mg dose groups. After multiple doses, the mean accumulation ratios of valbenazine and NBI-98782 were ~1.6 and 2.4, respectively. Plasma concentrations of valbenazine and NBI-98782 were similar between CYP2D6 normal and intermediate metabolizers. Valbenazine was well-tolerated in healthy Koreans, and its PK characteristics were similar to results previously reported in Americans.

Positive Correlation of Triacylglycerols with Increased Chain Length and Unsaturation with ω-O-Acylceramide and Ceramide-NP as Well as Acidic pH in the Skin Surface of Healthy Korean Adults.

Triacylglycerols (TG) play an important role in skin homeostasis including the synthesis of ω-O-acylceramides (acylCER) required for skin barrier formation by providing linoleic acid (C18:2n6). However, the overall relationships of TG species with various ceramides (CER) including CER-NP, the most abundant CER, ω-O-acylCER, and another acylCER, 1-O-acylCER in human SC, remain unclear. Therefore, we investigated these relationships and their influence on skin health status in healthy Korean adults. Twelve CER subclasses including two ω-O-acylCER and two 1-O-acylCER were identified with CER-NP consisting of approximately half of the total CER. The ω-O-acylCER species exhibited positive relationships with TG 52:4 and TG 54:2 containing C18:2, while interestingly, 1-O-acylCER containing ester-linked C14:0 and C16:0 demonstrated positive relationships with TG 46-50 including C14:0 and C16:0, respectively. In addition, CER-NP and CER-NH showed positive correlations with TG 52-54 containing C18:2 or C18:3. A lipid pattern with higher levels of CER including CER-NP and ω-O-acylCER with TG 54 and TG with 5-6 double bonds was related to good skin health status, especially with acidic skin pH. Collectively, TG with increased chain length and unsaturation seemed to improve CER content, and profiles such as higher acylCER and CER-NP improved skin health status by fortifying skin barrier structure.

Variations in the Second Derivative of a Photoplethysmogram with Age in Healthy Korean Adults.

Second derivative of photoplethysmogram (SDPTG) indices correlate with aging and vascular health. The trend of SDPTG indices with age has not yet been studied in the Korean population. Various SDPTG indices were measured in 300 healthy Koreans (150 men and 150 women), aged 19−69 years, stratified into five age groups consisting of 60 people (30 men and 30 women) in each age group from their 20s to 60s. The values of the SDPTG indices clearly showed distinct variations with age in healthy Korean groups (p < 0.001 for all indices). b/a increased linearly with age (y = 0.0045x − 0.803), as did SDPTG aging index (SDPTG-AI) (y = 0.0162x − 1.1389). c/a decreased linearly with age (y = −0.0044x + 0.1017), as did d/a (y = −0.0062x + 0.034) and e/a (y = −0.001x + 0.2002). A significant sex difference was shown in b/a and e/a ratios and SDPTG-AI (p < 0.001 for all indices); women had a higher b/a ratio (−0.55 ± 0.14 versus −0.65 ± 0.13) and SDPTG-AI (−0.33 ± 0.3 versus −0.52 ± 0.33) and a lower e/a ratio (0.13 ± 0.06 versus 0.18 ± 0.07) than men. A linear regression model of diverse SDPTG indices was provided according to the age of healthy Koreans, which may be valuable in preventing diseases related to vascular conditions by estimating the degradation of arterial function.

Effects of CYP2D6*10 allele on the pharmacokinetics of tolperisone.

Tolperisone, a muscle relaxant used for post-stroke spasticity, has been reported to have a very wide interindividual pharmacokinetic variability. It is metabolized mainly by CYP2D6 and, toa lesser extent, by CYP2C19 and CYP1A2. CYP2D6 is a highly polymorphic enzyme, and CYP2D6*wt/*wt, CYP2D6*wt/*10 and CYP2D6*10/*10 genotypes constitute more than 90% ofthe CYP2D6 genotypes inthe Korean population. Thus, effects of theCYP2D6*10 on tolperisone pharmacokinetics were investigated in this study to elucidate the reasons for the wide interindividual variability. Oral tolperisone 150mg was given to sixty-four healthy Koreans, and plasma concentrations of tolperisone were measured by liquid chromatography-tandem mass spectrometry (LC-MS/MS). The CYP2D6*10/*10 and CYP2D6*wt/*10 groups had significantly higher Cmax and lower CL/F values than the CYP2D6*wt/*wt group. The AUCinf of CYP2D6*10/*10 and CYP2D6*wt/*10 groups were 5.18-fold and 2.25-fold higher than the CYP2D6*wt/*wt group, respectively. There were considerable variations in the Cmax and AUC values within each genotype group, and the variations were greater as the activity of CYP2D6 decreased. These results suggest that the genetic polymorphism of CYP2D6 significantly affected tolperisone pharmacokinetics and factor(s) other than CYP2D6 may also have significant effects on the pharmacokinetics of tolperisone.

Pharmacokinetic Comparison of Ginsenosides between Fermented and Non-Fermented Red Ginseng in Healthy Volunteers.

Fermentation of red ginseng (RG) produces fermented red ginseng (FRG), thereby increasing the relative amount of downstream ginsenosides, including compound Y (CY), F2, Rh2, compound K (CK), compound O, protopanaxadiol (PPD), and protopanaxatriol (PPT). These downstream ginsenosides have beneficial pharmacological effects, and are easily absorbed by the human body. Based on these expectations, a randomized, single-dose, two-period, crossover clinical trial was planned to compare the pharmacokinetic characteristics of seven types (Rb1, CY, F2, CK, Rh2, PPD, and PPT) of ginsenoside components after FRG and RG administration. The safety and tolerability profiles were assessed in this clinical trial. Sixteen healthy Korean male subjects were administered 6 g of FRG or RG. All ginsenosides except Rb1 showed higher systemic exposure after FRG administration than after RG administration, based on comparisons of ginsenoside Cmax and area under the concentration-time curve (AUC) between FRG and RG. CK, the main ginsenoside component produced during the fermentation process, had 69.23/74.53-fold higher Cmax/AUClast after administration of FRG than RG, and Rh2 had 20.27/18.47-fold higher Cmax/AUClast after administration of FRG than RG. In addition, CY and F2 were detected in FRG; however, all plasma concentrations of CY and F2, except in one subject, were below the lower limit of quantification in RG. There were no clinically significant findings with respect to clinical laboratory tests, blood pressures, or adverse events. Therefore, regular administration of FRG may exert better pharmacological effects than RG.

Transcriptome expression profile of compound-K-enriched red ginseng extract (DDK-401) in Korean volunteers and its apoptotic properties.

Ginseng and ginsenosides have been reported to have various pharmacological effects, but their efficacies depend on intestinal absorption. Compound K (CK) is gaining prominence for its biological and pharmaceutical properties. In this study, CK-enriched fermented red ginseng extract (DDK-401) was prepared by enzymatic reactions. To examine its pharmacokinetics, a randomized, single-dose, two-sequence, crossover study was performed with eleven healthy Korean male and female volunteers. The volunteers were assigned to take a single oral dose of one of two extracts, DDK-401 or common red ginseng extract (DDK-204), during the initial period. After a 7-day washout, they received the other extract. The pharmacokinetics of DDK-401 showed that its maximum plasma concentration (Cmax) occurred at 184.8 ± 39.64ng/mL, Tmax was at 2.4h, and AUC0-12h was 920.3 ± 194.70ng h/mL, which were all better than those of DDK-204. The maximum CK absorption in the female volunteers was higher than that in the male volunteers. The differentially expressed genes from the male and female groups were subjected to a KEGG pathway analysis, which showed results in the cell death pathway, such as apoptosis and necroptosis. In cytotoxicity tests, DDK-401 and DDK-204 were not particularly toxic to normal (HaCaT) cells, but at a concentration of 250μg/mL, DDK-401 had a much higher toxicity to human lung cancer (A549) cells than DDK-204. DDK-401 also showed a stronger antioxidant capacity than DDK-204 in both the DPPH and potassium ferricyanide reducing power assays. DDK-401 reduced the reactive oxygen species production in HaCaT cells with induced oxidative stress and led to apoptosis in the A549 cells. In the mRNA sequence analysis, a signaling pathway with selected marker genes was assessed by RT-PCR. In the HaCaT cells, DDK-401 and DDK-204 did not regulate FOXO3, TLR4, MMP-9, or p38 expression; however, in the A549 cells, DDK-401 downregulated the expressions of MMP9 and TLR4 as well as upregulated the expressions of the p38 and caspase-8 genes compared to DDK-204. These results suggest that DDK-401 could act as a molecular switch for these two cellular processes in response to cell damage signaling and that it could be a potential candidate for further evaluations in health promotion studies.

Gene Dose-Dependent and Additive Effects of ABCG2 rs2231142 and SLC2A9 rs3733591 Genetic Polymorphisms on Serum Uric Acid Levels.

This study aimed to evaluate whether the single nucleotide polymorphisms of ATP-binding cassette subfamily G member 2 (ABCG2) and solute carrier family 2 member 9 (SLC2A9) affect individual blood uric acid levels using pyrosequencing. ABCG2 (rs2231142, rs72552713, rs2231137), SLC2A9 (rs3734553, rs3733591, rs16890979), and individual uric acid levels were prospectively analyzed in 250 healthy young Korean male participants. Prominent differences in uric acid levels of the alleles were observed in the SLC2A9 rs3733591 polymorphism: wild-type (AA) vs. heterozygote (AG), 0.7 mg/dL (p &lt; 0.0001); AA vs. mutant type (GG), 1.32 mg/dL (p &lt; 0.0001); and AG vs. GG, 0.62 mg/dL (p &lt; 0.01). In ABCG2 single nucleotide polymorphisms (SNPs), the statistically significant differences in uric acid levels were only found in rs2231142 between CC vs. AA (1.06 mg/dL; p &lt; 0.001), and CC vs. CA (0.59 mg/dL; p &lt; 0.01). Serum uric acid levels based on the ABCG2 and SLC2A9 diplotype groups were also compared. The uric acid levels were the lowest in the CC/AA diplotype and highest in the AA/AG diplotype. In addition, the SNP SLC2A9 rs3733591 tended to increase the uric acid levels when the ABCG2 rs2231142 haplotypes were fixed. In conclusion, both the ABCG2 rs2231142 and SLC2A9 rs3733591 polymorphisms may additively elevate blood uric acid levels.

Long working hours and the risk of hypothyroidism in healthy Korean workers: a cohort study.

Long working hours have been reported to cause various health problems, but are currently practiced in many countries. Building upon a previous cross-sectional study, the authors aimed to elucidate the causal relationship between long working hours and hypothyroidism through a longitudinal study. Data were collected at baseline from 45,259 participants without thyroid disease and with consistent weekly working hours (36-40, 41-52, 53-60, and >60 hours) during the follow-up period. Hypothyroidism was defined using the reference limits of serum thyroid-stimulating hormone and free thyroxine levels. By estimating hazard ratios (HRs) and 95% confidence intervals (CIs) using Cox proportional hazards regression analysis, the risk of incident hypothyroidism was evaluated with 36-40 hours of work per week as the reference. During 138,261.7 person-years of follow-up, 2,914 participants developed hypothyroidism (incidence density, 2.11/102 person-years). The multivariable-adjusted HRs of incident hypothyroidism for 41-52 hours, 53-60 hours, and >60 hours of work per week were 1.13 (95% CI, 1.03 to 1.24), 2.53 (95% CI, 2.17 to 2.95), and 2.57 (95% CI, 2.09 to 3.15), respectively. In dose-response analyses, long working hours had an approximately linear relationship with hypothyroidism incidence. The risk of incident hypothyroidism in those who worked 53-60 hours and >60 hours per week compared with the reference group was significantly higher among the older age group (≥36 years, stratified by median age), men, and daytime workers. This large-scale cohort study demonstrated the association between long working hours and an increased risk of incident hypothyroidism with a dose-response relationship.

Age Group-specific Reference Intervals for the Elecsys Anti-Müllerian Hormone Assay in Healthy Korean Women: a Nationwide Population-based Study.

Anti-Müllerian hormone (AMH) is one of the most reliable markers of ovarian reserve. Automated AMH assays are widely used in clinical laboratories, but reference intervals for the Elecsys AMH assay for Asian populations have not yet been determined. We aimed to determine reference intervals in healthy Korean women. The study included 1,450 women aged 19 to 54 years who participated in the Korea National Health and Nutrition Examination Survey between 2013 and 2016. The study participants were divided into seven 5-year age groups. AMH and progesterone concentrations were measured using Roche Elecsys assays, and bone morphogenetic protein-15 (BMP15) was genotyped for the detection of major variants. Age group-specific reference intervals for AMH were established as recommended by the CLSI EP28-A3c guidelines. The mean age was 37.4 years. AMH concentrations decreased with increasing age, especially after 40 years, with the median AMH decreasing from 30.9 pmol/L in participants of 19-24 years to 0.071 pmol/L in participants of 50-54 years. The mid-95 percentile AMH reference intervals decreased from 7.93-81.21 pmol/L in participants of 19-24 years to 0.07-3.86 pmol/L in participants of 50-54 years. Disease-associated BMP15 variants were not detected. We determined Elecsys AMH assay reference intervals in healthy Korean women. The results may provide basic information for the interpretation of AMH concentrations and assessment of ovarian reserve in Korean women.

No Association Between NPAS2 rs6425296 Polymorphism and Seasonality, Diurnal Preference in Koreans

Objective: Seasonal variations in mood and behavior and diurnal preference are associated with several genes that regulate circadian rhythms. In this study, we investigated the association of the &lt;i&gt;NPAS2&lt;/i&gt; rs6725296 polymorphism with seasonality and diurnal preference.Methods: A total of 510 healthy subjects were genotyped for the &lt;i&gt;NPAS2&lt;/i&gt; rs6725296 polymorphism and completed self-report questionnaires on seasonality and diurnal preferences. Seasonality was evaluated using the seasonal pattern assessment questionnaire, and diurnal preference was evaluated using the Composite Scale of Morningness (CSM). We assessed the association of genotype and allele carrier status with the total and subscale scores of global seasonality scores (GSS) for seasonality and the total and subscale scores of CSM for diurnal preference.Results: No significant associations were found between the &lt;i&gt;NPAS2&lt;/i&gt; rs6725296 genotype and the allele carrier status and the GSS and CSM scores.Conclusion: The results of this study suggest that the &lt;i&gt;NPAS2&lt;/i&gt; rs6725296 polymorphism may not contribute to seasonality and diurnal preference in healthy Koreans. More studies with a larger number of subjects, inclusion of different ethnic groups, and complementation with objective measurements of seasonality and diurnal preference are necessary to evaluate the influence of genetics on seasonality and diurnal preference.

Association between Diet Quality and Periodontitis in Korean Population

Objectives: The aim of this study was to examine the association between the diet quality and periodontiti for Korean population.&#x0D; Methods: The total number of participants in the KNHANES was 7,943. Periodontitis was defined as Community Periodontal Index. Diet quality was evaluated using the Korean Healthy Eating Index (KHEI) following adequacy, moderation, and balance components.&#x0D; Results: The lowest KHEI total score was associated with periodontitis and severe periodontitis. Especially, lower fruit intake was associated with periodontitis, while lower have breakfast, lower total fruits, meat fish, eggs, and beans intake, and lower carbohydrate and fat energy balance were associated with severe periodontitis.&#x0D; Conclusions: Diet quality had a more significant effect on severe periodontitis than on periodontitis. It is necessary to pay attention to diet quality to better oral health.

Dose-dependent reduction of lymphocyte count and heart rate after multiple administration of LC51-0255, a novel sphingosine-1-phosphate receptor 1 modulator, in healthy subjects.

Aim: Sphingosine-1-phosphate receptor mediates the egress of lymphocytes from lymphoid organs, and its inhibition results in a decreased number of circulating lymphocytes. The aim of the current study was to investigate the safety and pharmacodynamic and pharmacokinetic characteristics of a novel sphingosine-1-phosphate receptor modulator, LC51-0255. Methods: A phase 1 randomized, double-blind, placebo-controlled, multiple dosing, dose-escalation study was conducted on healthy Korean male subjects. Results: After single and daily administration of LC51-0255 for 21 days, a dose-dependent decrease in lymphocyte count and heart rate was observed through 0.25–2 mg dose range of LC51-0255. The mean elimination half-life of LC51-0255 was 76–95 h. LC51-0255 was accumulated with a mean accumulation ratio of 5.17–6.64. During the study, LC51-0255 was generally well tolerated. The most common treatment-emergent adverse event was bradycardia. No clinically significant event of arrhythmia, including AV block, was observed. No clinically significant difference in blood pressure was observed between the dose groups. In other safety assessments, no clinically significant abnormalities were observed, except for bradycardia. Conclusion: Daily administration of LC51-0255 in the range of 0.25–2 mg resulted in a dose-dependent reduction of lymphocyte counts and heart rate. LC51-0255 is generally safe and well tolerated in healthy volunteers.

Higher Levels of Serum Uric Acid Have a Significant Association with Lower Incidence of Lower Urinary Tract Symptoms in Healthy Korean Men.

Gout has been correlated with the risk of incident benign prostatic hyperplasia. In line with increasing prevalence of hyperuricemia, the aim of this study was to investigate the relationship between serum uric acid (SUA) level and the incidence of lower urinary tract symptoms (LUTS) among clinically healthy middle-aged men. We performed a cohort study in 101,091 Korean men without LUTS at baseline who completed health checkups between 2011 and 2016. LUTS were evaluated using the International Prostate Symptom Score, where a score ≥ 8 was defined as significant LUTS. Men were divided into six groups according to their SUA levels in mg/dL (<5.5, 5.5–6.4, 6.5–7.4, 7.5–8.4, 8.5–9.4, and ≥9.5). Throughout the follow-up—encompassing a total of 358,982.6 person years—13,424 people had significant LUTS (37.3 per 1000 person years for incidence rate). The multivariable models demonstrated that the highest level of SUA (≥9.5 mg/dL) was related to the lowest risk of significant LUTS compared with the reference category (<5.5 mg/dL) (0.77 (95% CI 0.59–0.99) for adjusted HR). In this large cohort composed of middle-aged men, higher SUA levels were related to a reduced risk of LUTS. This result suggests another potential role of SUA in restraining LUTS. Additional studies are needed to explain the underlying biological mechanisms of this phenomenological relationship.

Normal Values of Central, Peripheral, and Root Motor Conduction Times in a Healthy Korean Population.

Central, peripheral, and root motor conduction times (CMCTs, PMCTs, and RMCTs, respectively) are valuable diagnostic tools for spinal cord and motor nerve root lesions. We investigated the normal values and the effects of age and height on each motor conduction time. This study included 190 healthy Korean subjects who underwent magnetic stimulation of the cortex and spinous processes at the C7 and L1 levels. Recording muscles were abductor pollicis brevis and abductor digiti minimi in the unilateral upper limb and extensor digitorum brevis and abductor hallucis in the contralateral lower limb. F-wave and compound motor nerve action potentials were also recorded. Central motor conduction time was evaluated as the difference between cortical motor evoked potential onset latency and PMCT using calculation and spinal stimulation methods. Root motor conduction time was computed as the difference between spinal stimulated and calculated CMCTs. The average age and height of the participants were 41.21 ± 14.39 years and 164.64 ± 8.27 cm, respectively; 39.5% (75/190) patients were men. In the linear regression analyses, upper limb CMCTs showed a significant and weak positive relationship with height. Lower limb CMCTs demonstrated a significant and weak positive relationship with age and height. Peripheral motor conduction times were significantly and positively correlated with age and height. Root motor conduction times showed no significant relationship with age and height, except for abductor pollicis brevis-RMCT, which had a weak negative correlation with height. This study provides normal values of CMCTs, PMCTs, and RCMTs, which have potential clinical applications. When interpreting CMCTs, age and height should be considered.

Familial Types and Dietary Quality in Korean Elderly

Background: The aim of this study is to assess the relationships between familial types and dietary quality measured by the Korean Healthy Eating Index (KHEI) in representative Korean elderly.Methods: We used cross-sectional data from 4,260 Korean elderly, aged over 65 years, who had participated in the 2016-2018 Korea National Health and Nutrition Examination Survey. The 14-item KHEI scores were calculated from the Food Frequency Questionnaire and the Dietary Habit Survey from the Nutrition Survey.Familial type was categorized into three groups of Live alone (LA), Live with a partner with or without other(s) (LP), and Live with other(s) without a partner (LO) based on the Household Interview Survey.Results: LP had better dietary quality than LO for both sexes (both P&lt;0.05). LA (64.5; standard error [SE], 1.0) had worse dietary quality than LP (66.7; SE, 0.6]) in elderly male (P&lt;0.05) while they were not significantly different in elderly female. The percentages of subjects having poor dietary quality (total KHEI score of ≤50) in LA, LP, and LO were 20.6% (SE, 2.7), 7.3% (SE, 0.8), 8.9% (SE, 3.6) in elderly male, and 9.6% (SE, 1.2), 5.7% (SE, 0.8), 12.9% (SE, 1.8) in elderly female, respectively. The multivariate-adjusted odds ratios of having poor dietary quality compared with LP was 2.45 (95% confidence interval [CI], 1.66-3.60) for LA male, and 1.98 (95% CI, 1.19-3.28) for LO female.Conclusions: Familial type affects dietary quality in Korean elderly. However, differential associations were shown between elderly male and female.

Population Pharmacokinetic Model of AST-001, L-Isomer of Serine, Combining Endogenous Production and Exogenous Administration in Healthy Subjects.

AST-001 is an L-isomer of serine that has protective effects on neurological disorders. This study aimed to establish a population pharmacokinetic (PK) model of AST-001 in healthy Korean to further propose a fixed-dose regimen in pediatrics. The model was constructed using 648 plasma concentrations from 24 healthy subjects, including baseline endogenous levels during 24 h and concentrations after a single dose of 10, 20, and 30 g of AST-001. For the simulation, an empirical allometric power model was applied to the apparent clearance and volume of distribution with body weight. The PK characteristics of AST-001 after oral administration were well described by a two-compartment model with zero-order absorption and linear elimination. The endogenous production of AST-001 was well explained by continuous zero-order production at a rate of 0.287 g/h. The simulation results suggested that 2 g, 4 g, 7 g, 10 g, and 14 g twice-daily regimens for the respective groups of 10–14 kg, 15–24 kg, 25–37 kg, 38–51 kg, 52–60 kg were adequate to achieve sufficient exposure to AST-001. The current population PK model well described both observed endogenous production and exogenous administration of AST-001 in healthy subjects. Using the allometric scaling approach, we suggested an optimal fixed-dose regimen with five weight ranges in pediatrics for the upcoming phase 2 trial.

Trends in Diet Quality and Cardiometabolic Risk Factors Among Korean Adults, 2007-2018

Few studies have examined the dietary trends in Korea beyond evaluating selected food groups. To help prevent cardiometabolic disease burdens, a comprehensive investigation of the trends in overall diet quality and identification of possible contributing factors would be useful. To investigate the trends and independent associations of age, period, and birth cohort with diet quality and cardiometabolic risk factors among Korean adults. Serial cross-sectional and age-period-cohort analyses were conducted of nationally representative 24-hour dietary recall data from the Korea National Health and Nutrition Examination Survey 2007-2018. The study population included 65 416 Korean adults aged 19 to 79 years. Data analyses were conducted from March 1, 2020, through April 30, 2021. Age, calendar year, birth cohort, and population sociodemographic characteristics. Korean Healthy Eating Index (KHEI), a validated diet quality score (range, 0-90, with higher scores indicating greater diet quality), and 8 cardiometabolic risk factors (waist circumference and systolic blood pressure, diastolic blood pressure, serum total cholesterol, low-density lipoprotein cholesterol, high-density lipoprotein cholesterol, triglyceride, and fasting blood glucose levels). Among 65 416 participants, mean age (SD) was 44.5 (0.1) years and 36 631 were women (55.8%). In 2007-2018, the age-standardized mean (SE) KHEI score increased from 51.0 (0.4) to 52.1 (0.5), which was associated with reduced sodium intake and increased whole grain, dairy, and protein-rich food intakes. The mean (SE) KHEI score was lowest at age 39 years (50.1 [0.3]) and increased at older ages (58.0 [0.3] at 79 years). Controlling for age and period effects, the highest KHEI score was observed among the birth cohorts of 1960-1964 (53.6 [0.9]) and decreased in subsequent cohorts (45.5 [1.2] in the 1990-1999 birth cohort). Similar cohort effects in cardiometabolic risk factors were observed, showing the lowest waist circumference, blood pressure, and total cholesterol levels among the birth cohorts of the 1960s and 1970s and higher levels among more recent birth cohorts (1990-1999 vs 1960-1964: waist circumference, 83.8 [0.5] vs 81.4 [0.4] cm; systolic blood pressure, 118.7 [0.7] vs 116.4 [0.4] mm Hg; total cholesterol, 200.2 [0.9] vs 198.9 [0.7] mg/dL). At most ages, periods, and birth cohorts, the mean KHEI score was consistently higher in adults living in urban areas (at age 45 years: 50.5 [1.0] vs 49.7 [0.9] rural) and among high-income (at age 45 years: 50.7 [1.1] vs 49.3 [0.9] low income) and educational levels (at age 45 years: 53.1 [0.9] vs 49.1 [1.0] low educational level). The findings of this study suggest that, from 2007 to 2018, the diet quality of Korean adults modestly improved. Despite the improvement, inequalities in diet among age, birth cohort, and socioeconomic subgroups persisted, suggesting that more intense interventions may be needed to target the susceptible groups.