Association of exposure to secondhand smoke at home with early age at menarche in South Korea.

OBJECTIVES: The secular trend in age at menarche (AAM) has declined both worldwide and in Korea. Early AAM is associated with the risk of several diseases, reproductive capacity, and psychological problems. We aimed to investigate the relationship between secondhand smoke (SHS) exposure at home and early puberty onset using AAM in Korean adolescents. STUDY DESIGN: This is a retrospective cross-sectional study. METHODS: This study used data from the Korea Youth Risk Behavior Web-based Survey 2014-2015. We used the mean AAM (12.2 years) as a determinant of early AAM. After the exclusion of girls without menarche or who did not respond, the total population comprised 63,618 participants. We categorized AAM as 'early' and 'average or late.' Adolescents with SHS exposure were assigned to the 'never exposed,' 'light exposure,' and 'heavy exposure' groups. Multiple logistic regression analyses were performed. RESULTS: We observed a positive association, approximately 1.12 times, between early AAM and high SHS exposure (odds ratio [OR], 1.12; 95% confidence interval [CI], 1.05-1.19). Girls who started smoking before the age of 12 years (OR, 1.68; 95% CI, 1.41-1.99) showed a stronger association with early AAM than non-smokers. Active smoking showed a stronger association with early AAM. Never smokers with high SHS exposure at home were 1.13 times likelier to have an early AAM (OR, 1.13; 95% CI, 1.05-1.22) than those without SHS exposure. CONCLUSIONS: In addition to active smoking, SHS may also be a risk factor for early AAM. Education aimed at active and secondhand smoking prevention is needed to protect children against early AAM.

Quantitative characterization of the regulation of iron metabolism in glioblastoma stem-like cells using magnetophoresis.

This study focuses on different iron regulation mechanisms of glioblastoma (GBM) cancer stem-like cells (CSCs) and non-stem tumor cells (NSTCs) using multiple approaches: cell viability, density, and magnetophoresis. GBM CSCs and NSTCs were exposed to elevated iron concentration, and their magnetic susceptibility was measured using single cell magnetophoresis (SCM), which tracks the magnetic and settling velocities of thousands of individual cells passing through the magnetic field with a constant energy gradient. Our results consistently demonstrate that GBM NSTCs have higher magnetic susceptibility distribution at increased iron concentration compared with CSCs, and we speculate that it is because CSCs have the ability to store a high amount of iron in ferritin, whereas the free iron ions inside the NSTCs lead to higher magnetic susceptibility and reduced cell viability and growth. Further, their difference in magnetic susceptibility has led us to pursue a separate experiment using a quadrupole magnetic separator (QMS), a novel microfluidic device that uses a concentric channel and permanent magnets in a special configuration to separate samples based on their magnetic susceptibilities. GBM CSCs and NSTCs were exposed to elevated iron concentration, stained with two different trackers, mixed and introduced into QMS; subsequently, the separated fractions were analyzed by fluorescent microscopy. The separation results portray a successful label-less magnetic separation of the two populations.

Case management effectiveness for managing chronic illnesses in Korea: a systematic review.

BACKGROUND: Case management has been adopted in Korea and been recognized as a promising care-coordination method that lowers costs and improves quality of care. However, the effectiveness of case management among individuals with chronic illnesses who reside in the community has yet to be established. AIM: This systematic review identifies and synthesizes recent evidence of case management's effectiveness in managing chronic illnesses among adults in Korea. METHODS: The methodology of this systematic review was guided by the Cochrane processes and PRISMA statements. A search of multiple bibliographic databases to identify studies of case management in the populations of Koreans adult with chronic illnesses was conducted. Studies that met the inclusion criteria were published in English or Korean. Nine empirical peer-reviewed studies published between 2008 and 2016 were selected for review. RESULTS: The retrieved studies show that case management programmes in Korea for adults with chronic illness in the community were led by nurses. There was strong evidence that nurse-led case management was effective in improving psychobehavioural and objective clinical outcomes; however, results for health services utilization outcomes were mixed. CONCLUSION: In future, research with rigorous study designs and large sample size in multiple settings are needed to further assess the effectiveness of case management in Korea. IMPLICATIONS FOR NURSING AND HEALTH POLICY: Nurse-led case management would be of support in the care of chronic illnesses not only in Korea but also in Asian countries which share standard practice of case management with Korea. Nursing leaders should allocate resources to sponsor educational resources and practical strategies for evidence-based case management.

Novel associations between blood DNA methylation and body mass index in middle-aged and older adults.

BACKGROUND/OBJECTIVES: There is increasing evidence of a relationship between blood DNA methylation and body mass index (BMI). We aimed to assess associations of BMI with individual methylation measures (CpGs) through a cross-sectional genome-wide DNA methylation association study and a longitudinal analysis of repeated measurements over time. SUBJECTS/METHODS: Using the Illumina Infinium HumanMethylation450 BeadChip, DNA methylation measures were determined in baseline peripheral blood samples from 5361 adults recruited to the Melbourne Collaborative Cohort Study (MCCS) and selected for nested case-control studies, 2586 because they were subsequently diagnosed with cancer (cases) and 2775 as controls. For a subset of 1088 controls, these measures were repeated using blood samples collected at wave 2 follow-up, a median of 11 years later; weight was measured at both time points. Associations between BMI and blood DNA methylation were assessed using linear mixed-effects regression models adjusted for batch effects and potential confounders. These were applied to cases and controls separately, with results combined through fixed-effects meta-analysis. RESULTS: Cross-sectional analysis identified 310 CpGs associated with BMI with P<1.0 × 10-7, 225 of which had not been reported previously. Of these 225 novel associations, 172 were replicated (P<0.05) using the Atherosclerosis Risk in Communities (ARIC) study. We also replicated using MCCS data (P<0.05) 335 of 392 associations previously reported with P<1.0 × 10-7, including 60 that had not been replicated before. Associations between change in BMI and change in methylation were observed for 34 of the 310 strongest signals in our cross-sectional analysis, including 7 that had not been replicated using the ARIC study. CONCLUSIONS: Together, these findings suggest that BMI is associated with blood DNA methylation at a large number of CpGs across the genome, several of which are located in or near genes involved in ATP-binding cassette transportation, tumour necrosis factor signalling, insulin resistance and lipid metabolism.

Experiences of case management with chronic illnesses: a qualitative systematic review.

AIM: This qualitative systematic review aimed to identify and synthesize recent qualitative studies to improve understanding of the experiences and perceptions of case management interventions that individuals with chronic illnesses and their caregivers have. BACKGROUND/INTRODUCTION: Case management has been shown to be effective at improving quality of care and lowering costs for individuals with chronic illnesses. However, no qualitative review has been synthesized with recent qualitative studies about case management experiences by individual with chronic illnesses. METHODS: This qualitative systematic review uses a thematic synthesis method to review 10 qualitative studies published within the last 10 years, from 2007 to 2016, thereby identifying and discussing the understandings that individuals with chronic illnesses and their caregivers have about case management. RESULTS: From this synthesis, three themes were identified as facilitators of case management (access to healthcare resources, health status supports and emotional aid) and two themes were identified as barriers to it (low information about case management and time constraints). CONCLUSIONS: This is the first qualitative systematic review of the perceptions and experiences that individuals with chronic illnesses and their caregivers have about case management. The facilitators of case management can be employed to inform patients about the benefits of case management and to improve population health. IMPLICATIONS FOR NURSING AND HEALTH POLICY: The findings about barriers to case management can be used to reform case management for populations with chronic illnesses. These factors should be considered by nursing researchers and healthcare policymakers when implementing case management.

Case management effectiveness in reducing hospital use: a systematic review.

AIM: This systematic review synthesizes recent evidence of the effectiveness of case management in reducing hospital use by individuals with chronic illnesses. BACKGROUND: Hospital use by individuals with chronic illnesses accounts for 66% of healthcare costs in the United States. its has been cited as care coordination that can reduce healthcare costs; however, its effectiveness in improving hospital use outcomes is contradictory, and no review has yet synthesized recent studies of case management with respect to hospital use outcomes. METHODS: This systematic review followed the Cochrane processes and was guided by use of PRISMA statements. Five electronic databases were searched to obtain randomized controlled trials published within the last 10 years that evaluated case management hospital use as a primary outcome by individuals with chronic illnesses. RESULTS: Ten studies published between 2007 and 2015 were retrieved and assessed for risk of methodological bias. All studies used case management as an intervention, focused on transitional care services and reported hospital use, including readmissions and emergency department and hospital visits, as a primary outcome. Analysis of the studies showed that case management greatly reduced hospital readmissions and emergency department visits. LIMITATIONS: Only studies published in English were searched, and retrieved studies tended to report positive results. CONCLUSIONS: There was strong evidence of significant reductions in hospital use with case management as an intervention. However, other results about the efffectiveness of case management remain mixed; more rigorously designed studies with case management interventions are needed. IMPLICATIONS FOR NURSING AND HEALTH POLICY: The complexity and cost of chronic illnesses means that case management should be considered as a tool to improve quality of care and lower healthcare costs.

The acute effects of time-of-day-dependent high fat feeding on whole body metabolic flexibility in mice.

BACKGROUND: Both circadian disruption and timing of feeding have important roles in the development of metabolic disease. Despite growing acceptance that the timing of food consumption has long-term impact on metabolic homeostasis, little is known regarding the immediate influence on whole body metabolism, or the mechanisms involved. We aimed to examine the acute effects of time-of-day-dependent high fat feeding on whole body substrate metabolism and metabolic plasticity, and to determine the potential contribution of the adipocyte circadian clock. METHODS: Mice were fed a regimen of 4-h meal at the beginning and end of the dark (waking) cycle, separated by 4 h of fasting. Daily experimental conditions consisted of either an early very high fat or high fat (EVHF or EHF, 60 or 45% kcals from fat, respectively) or late (LVHF or LHF) meal, paired with a low fat (LF, 10% kcals from fat) meal. Metabolic parameters, glucose tolerance, body fat composition and weight were assessed. To determine the role of the adipocyte circadian clock, an aP2-CLOCK mutant (ACM) mouse model was used. RESULTS: Mice in the EVHF or EHF groups showed a 13.2 or 8.84 higher percentage of caloric intake from fat and had a 0.013 or 0.026 lower daily average respiratory exchange ratio, respectively, compared with mice eating the opposite feeding regime. Changes in glucose tolerance, body fat composition and weight were not significant at the end of the 9-day restricted feeding period. ACM mice did not exhibit different metabolic responses to the feeding regimes compared with wild-type littermates. Circadian clock disruption did not influence the short-term response to timed feeding. CONCLUSIONS: Both the total fat composition of diet and the timing of fat intake may differentially mediate the effect of timed feeding on substrate metabolism, but may not induce acute changes in metabolic flexibility.

Widespread cortical thinning in patients with neuromyelitis optica spectrum disorder.

BACKGROUND AND PURPOSE: Studies on cortical involvement and its relationship with cognitive function in patients with neuromyelitis optica spectrum disorder (NMOSD) remain scarce. The objective of this study was to compare cortical thickness on magnetic resonance imaging (MRI) between patients with NMOSD and multiple sclerosis (MS) and to investigate its relationship with clinical features and cognitive function. METHODS: This observational clinical imaging study of 91 patients with NMOSD, 52 patients with MS and 44 healthy controls was conducted from 1 December 2013 to 30 April 2015 at the institutional referral center. Three tesla MRI of the brain and neuropsychological tests were performed. Cortical thickness was measured using three-dimensional surface-based analysis. RESULTS: Both sets of patients exhibited cortical thinning throughout the entire brain cortex. Patients with MS showed a significantly greater reduction in cortical thickness over broad regions of the bilateral frontal and parieto-temporal cortices and the left precuneus compared to those with NMOSD. Memory functions in patients with MS were correlated with broad regional cortical thinning, whereas no significant associations were observed between cortical thickness and cognitive function in patients with NMOSD. CONCLUSIONS: Widespread cortical thinning was observed in patients with NMOSD and MS, but the extent of cortical thinning was greater in patients with MS. The more severe cortical atrophy may contribute to memory impairment in patients with MS but not in those with NMOSD. These results provide in vivo evidence that the severity and clinical relevance of cortical thinning differ between NMOSD and MS.

Citrus-derived oil inhibits Staphylococcus aureus growth and alters its interactions with bovine mammary cells.

This experiment examined the effects of cold-pressed, terpeneless citrus-derived oil (CDO) on growth of Staphylococcus aureus, which a major cause of contagious bovine mastitis, and invasion of bovine mammary cells (MAC-T). To determine minimum inhibitory concentration, we used the broth dilution method, using CDO concentrations range from 0.0125 to 0.4% with 2-fold dilutions. Growth inhibition was examined by adding 0.00, 0.05, 0.025, 0.0125, and 0.00625% CDO to 10(5) cfu/mL S. aureus in nutrient broth and enumerating colonies after serial dilution. In a 96-well plate, S. aureus (10(7) cfu/mL) was allowed to form a biofilm, treated with 0, 0.025, 0.5, or 1% CDO, and then was measured using a spectrophotometer. Cytotoxic effect on immortalized MAC-T cells was also examined at various concentrations of CDO using a 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay. We observed that the minimum inhibitory concentration of CDO to inhibit the growth of S. aureus in vitro was 0.025% CDO. A time kill curve for CDO action on S. aureus over 4h was generated. The CDO completely eliminated S. aureus after 3h of incubation at a concentration of 0.25%, or after 2h of incubation at concentrations of 0.05%. It was also observed that CDO had no effect on preformed biofilms except at a concentration of 0.05%, in which a significant reduction in the measured absorbance was noted. In addition, the association and invasion of S. aureus to MAC-T cells were significantly inhibited after 1h of treatment with CDO. Citrus-derived oil was also able to increase cellular proliferation of MAC-T cells at concentrations up 0.05% and had no effect at a concentration of 0.1% after 1 h. Our data suggests that CDO should be considered for further research as a preventive and therapeutic against bovine mastitis.

Comparison of mechanical artificial shrinkage methods in mouse blastocyst vitrification.

PURPOSE OF INVESTIGATION: This study was designed to determine which mechanical artificial shrinkage (AS) method, conducted by puncture, pipetting, or aspiration, was effective in increasing the re-expansion rate of mouse blastocysts. MATERIALS AND METHODS: In each group, 30 mouse blastocysts were used. Before vitrification, the blastocoelic cavity was collapsed by puncture with a micro-needle, pipetting with a micro-glass pipette, and direct aspiration with an ICSI pipette. After thawing, the re-expansion rate of blastocysts was examined for each AS method. Re-expansion rate was checked at three, five, and seven hours after thawing. RESULTS: The number of re-expanded mouse blastocysts at five hours after thawing was 12 in the puncture with a micro-needle group, 11 in the pipetting with a micro-glass pipette group, and 24 in the direct aspiration with an ICSI pipette group. The cumulative number of re-expanded mouse blastocysts at seven hours after thawing was 20 in the puncture with a micro-needle group, 20 in the pipetting with a micro-glass pipette group, and 28 in the direct aspiration with an ICSI pipette group. There were statistically significant differences in the cumulative number of re-expanded mouse blastocysts between five and seven hours after thawing (p = 0.001 and 0.021, respectively). CONCLUSIONS: Direct aspiration with an ICSI pipette resulted in a higher re-expansion rate than the puncture and pipetting methods. It can be considered that the direct aspiration method is more convenient and simpler than the other two methods.

Incarceration of gravid uterus by growing subserosal myoma: case report.

Incarceration of gravid uterus is a rare condition, occurring in one in 3,000 to 10,000 pregnancies during second trimester. Incarceration of uterus can cause several complications, such as uterine rupture, labor dystocia, and uncontrollable postpartum hemorrhage. Early diagnosis is important to prevent these complications, but there are no standard treatments of incarceration of gravid uterus. The authors present a case report of incarceration of gravid uterus caused by growing subserosal myoma, which was treated with myomectomy during second trimester.

Barriers to and facilitators of diabetes self-management with elderly Korean-American immigrants.

AIM: The aim of this study was to explore barriers to and facilitators of diabetes self-management among first-generation Korean-American elderly immigrants with type 2 diabetes in the United States Midwest. BACKGROUND: The number of Korean-American elderly immigrants with type 2 diabetes in the United States is expected to increase because they are at risk of adopting a Western lifestyle. METHODS: Three focus groups (N = 18) and five individual interviews were conducted with Korean-American elderly immigrants with type 2 diabetes. Demographic characteristics and diabetes-related medical history information were obtained with a questionnaire. All data were digitally recorded, transcribed verbatim and translated from Korean into English. Transcripts were analysed using standard content-based analysis. RESULTS: Five perceived barriers were identified: the high cost of type 2 diabetes care, language issues, loss of self-control, memory loss and limited access to healthcare resources. Three perceived facilitators were time, seeking information, and family and peer supports. LIMITATIONS: The convenience samples and small sample size may limit the study. CONCLUSIONS: The barriers to and facilitators of diabetes self-management identified in this study can be used in the development of more age- and culturally sensitive diabetes interventions and resources. IMPLICATION FOR NURSING AND HEALTH POLICY: Nurses and healthcare providers can use this study's findings to develop patient-centred, age-appropriate and culturally appropriate diabetes interventions. There are urgent needs to train bilingual healthcare providers and staff and to provide translation services for Korean-American elderly immigrants. Finally, communities and social supports within public health policy are urgently needed for this ethnic minority group.

Overexpression of PI3K-p110α in the progression of uterine cervical neoplasia and its correlation with pAkt and DJ-1.

OBJECTIVE: To investigate the expression of PI3K-p110α, pAkt, PTEN, the signaling molecules from PI3K/Akt signaling pathway, DJ-1, an oncoprotein and HSP90a, a molecular chaperone, and their correlation in uterine cervical neoplasia, in order to elucidate their role in cervical carcinogenesis. MATERIALS AND METHODS: Using immunohistochemistry, the authors analyzed the expression of PI3K-p110α, pAkt, PTEN, DJ-1 and HSP90α, and their correlation in ten normal tissues, cervical intraepithelial neoplasia (CIN) including 30 CIN1 and 31 CIN3, and 33 cases of invasive squamous cell carcinoma (SCC). RESULTS: The expression of all proteins significantly increased in CIN3 compared to CIN1, and only the expression of PI3K-p110α significantly increased in invasive SCC compared to CIN3. There was a significant positive correlation between the expression of PI3K-p110α and DJ-1, as well as PI3K-p110α and pAkt in CIN3 and invasive SCC. CONCLUSION: Overexpression of PI3K-p110α is associated with progression of uterine cervical neoplasia, and the expression of pAkt and DJ-1 is positively correlated with PI3K-p110α expression in this process.

A case of idiopathic intracranial hypertension associated with PCOS.

Idiopathic intracranial hypertension (IIH) is a rare neurologic disorder. It is also known as pseudotumor cerebri. The incidence of IIH is one to two per 100,000 population annually. The higher incidence is in obese women from 15 to 44 years. The main symptoms are headache and visual loss. It mostly affects women of childbearing age who are overweight or obese. There are many theories of pathogenesis of IIH, but precise pathogenesis is unknown. One of the causes of IIH is intracranial venous sinus thrombosis. It can cause increased cerebrospinal fluid (CSF) pressure by obstruction of venous outflow and blocking of CSF absorption. In polycystic ovary syndrome (PCOS) patients, thrombogenic tendency is increased due to increased aromatization of testosterone to estradiol which could induce estrogen-mediated thrombophilia. The authors present a 14-year-old girl with PCOS stigma who presented with a severe headache and papilledema. These symptoms were not improved by standard medical therapy of IIH and PCOS, but improved after laparoscopic ovarian drilling. The authors report it with a review of the literature.

Community-based case management effectiveness in populations that abuse substances.

BACKGROUND: The number of persons who are substance abusing has been increasing globally. A majority of them remain in their communities, untreated. Empirical studies have shown some positive impacts of case management on substance abuse. However, studies that systematically synthesize the effectiveness of community-based case management with populations that abuse substances are limited. AIM: To review evidence of the impact of case management in improving treatment of substance abuse among adults in community settings. METHODS: The Cochrane processes guided this systematic review. PubMed, CINAHL, PsycINFO, Ovid and the Web of Science were searched to retrieve primary studies published from 2000 to 2013. All randomized controlled trials were considered for review. The methodological quality of the studies was assessed. RESULTS: The initial unfiltered search identified 506 references. A total of seven randomized controlled trials were selected for review. Findings show that, compared with clinical case management and usual care, community-based case management services significantly improved clients' ability to abstain from drug use, reduced social problems, supported unmet service needs and improved satisfaction. Studies also showed reduced use of healthcare services, but results were mixed. CONCLUSIONS: There is an evidence base for practicing case management among adults who are substance abusing. In general, studies concluded that case management is an active and assertive method of care coordination for formal substance abuse treatment. Further research is needed to assess case management's cost-effectiveness and the impact of dosage on client outcomes. IMPLICATIONS FOR NURSING POLICY: Because of the complexity of population health management across settings and over long time frames, evidence-based strategies are required to achieve health improvements. Because it provides continuous and timely care, healthcare leaders and policymakers should consider community-based case management as an important strategy for coordinating the care in populations that are substance abusing.

Association study of polymorphisms between the Radixin gene and rheumatoid arthritis in a Korean population.

Radixin (RDX) is part of the ezrin-radixin-moesin (ERM) protein family. It functions as a membrane-cytoskeletal linker in actin-rich cell surface structures and is thought to be essential for cortical cytoskeleton organization, cell motility, adhesion, and proliferation. An increase in phosphorylated ERM in fibroblast-like synoviocytes contributes to rheumatoid arthritis (RA) synovial hyperplasia. We examined the genetic association between the RDX gene and RA in a Korean population. To identify the relationship between RDX gene polymorphisms and RA, we genotyped 2 single nucleotide polymorphisms (SNPs; rs11213326 and rs12575162) of RDX using a direct sequencing method in 296 RA patients and 493 control subjects. In this study, the 2 SNPs showed no association with RA disease susceptibility. However, further analysis based on clinical information of the RA patient group showed that the SNPs were associated with the erythrocyte sedimentation rate (ESR) in RA patients. These data suggest an association between RDX polymorphisms and the clinical features of RA patients, particularly the ESR.

An integrative review of nurse-led community-based case management effectiveness.

BACKGROUND: Accountable, continuous and patient-centred care in community-based settings is increasingly needed to reduce fragmented care, especially to reduce patient readmission rates. Case management has been proven effective in reducing healthcare costs and in increasing continuity of care, but its effectiveness in community-based settings is not clear. AIM: The aim of this integrative review is to examine the effectiveness of community-based case management programmes in improving patient outcomes. METHODS: An integrative review of articles from PubMed, CINAHL and PsycInfo databases was undertaken to synthesize and analyse research about community-based case management and its outcomes. Studies looking for patient outcomes and empirical studies published since 2000 were included. A total 18 articles were retrieved from 2000 to 2013. RESULTS: Most of the included studies were conducted in the USA, but international studies with quantitative approaches were reviewed (n = 6). The review revealed that community-based case management significantly reduced hospital access outcomes, especially readmissions and increased cost effectiveness, patient clinical outcomes and patient satisfaction. LIMITATIONS: This study did not isolate studies of patients with diseases or demographic characteristics in common, resulting in large variations in disease and demographic factors. CONCLUSION: There is a base of evidence that community-based case management is effective. Because it provides quality, patient-centred care, case management should be used for major care coordination. IMPLICATIONS FOR NURSING AND HEALTH POLICY: The benefits of community-based case management need to be announced to healthcare leaders and policymakers.

Genome-scale profiling reveals a subset of genes regulated by DNA methylation that program somatic T-cell phenotypes in humans.

The aim of this study was to investigate the dynamics and relationship between DNA methylation and gene expression during early T-cell development. Mononuclear cells were collected at birth and at 12 months from 60 infants and were either activated with anti-CD3 for 24 h or cultured in media alone, and the CD4+ T-cell subset purified. DNA and RNA were co-harvested and DNA methylation was measured in 450 000 CpG sites in parallel with expression measurements taken from 25 000 genes. In unstimulated cells, we found that a subset of 1188 differentially methylated loci were associated with a change in expression in 599 genes (adjusted P value<0.01, ß-fold >0.1). These genes were enriched in reprogramming regions of the genome known to control pluripotency. In contrast, over 630 genes were induced following low-level T-cell activation, but this was not associated with any significant change in DNA methylation. We conclude that DNA methylation is dynamic during early T-cell development, and has a role in the consolidation of T-cell-specific gene expression. During the early phase of clonal expansion, DNA methylation is stable and therefore appears to be of limited importance in short-term T-cell responsiveness.

Anti-emetic effect of ondansetron and palonosetron in thyroidectomy: a prospective, randomized, double-blind study.

BACKGROUND: Palonosetron is a new potent 5-hydroxytryptamine 3 antagonist. Although this drug is thought to be more effective in patients receiving opioid-based patient-controlled analgesia (PCA), clinical data are lacking. This study compared the effects of i.v. ondansetron and palonosetron administered at the end of surgery in preventing postoperative nausea and vomiting (PONV) in high-risk patients receiving i.v. PCA after thyroidectomy. METHODS: A total of 100 female non-smoking subjects were randomly assigned into a palonosetron group or an ondansetron group. Ondansetron was given as an 8 mg bolus and 16 mg was added to the i.v. PCA mixture. In the palonosetron group, 0.075 mg was injected as a bolus only. Fentanyl-based PCA was provided for 24 h after operation. The incidence of nausea and vomiting, severity of nausea, requirement for rescue anti-emetics, and adverse effects were evaluated during 0-2 and 2-24 h. RESULTS: The incidence of PONV during the 24 h postoperative period was lower in the palonosetron group than in the ondansetron group (42% vs 62%, P=0.045). No differences were observed between the groups during the first 2 h. However, the incidence of nausea and vomiting and nausea severity were significantly lower in the palonosetron group than in the ondansetron group during 2-24 h. The only difference in the use of rescue anti-emetics was at 2-24 h (10% with palonosetron compared with 28% with ondansetron, P=0.02). CONCLUSIONS: Palonosetron is more effective than ondansetron for high-risk patients receiving fentanyl-based PCA after thyroidectomy, especially 2-24 h after surgery.