BACKGROUND: Dengue hemorrhagic fever (DHF) is the severe and life-threatening syndrome that can develop after infection with any one of the four dengue virus (DENV) serotypes. DHF occurs almost exclusively in individuals with secondary heterologous DENV infections and infants with primary DENV infections born to dengue immune mothers. The widely accepted explanation for the pathogenesis of DHF in these settings, particularly during infancy, is antibody-dependent enhancement (ADE) of DENV infection. METHODS AND FINDINGS: We conducted a prospective nested case-control study of DENV infections during infancy. Clinical data and blood samples were collected from 4,441 mothers and infants in up to two pre-illness study visits, and surveillance was performed for symptomatic and inapparent DENV infections. Pre-illness plasma samples were used to measure the associations between maternally derived anti-DENV3 antibody-neutralizing and -enhancing capacities at the time of DENV3 infection and development of infant DHF. The study captured 60 infants with DENV infections across a wide spectrum of disease severity. DENV3 was the predominant serotype among the infants with symptomatic (35/40) and inapparent (15/20) DENV infections, and 59/60 infants had a primary DENV infection. The estimated in vitro anti-DENV3 neutralizing capacity at birth positively correlated with the age of symptomatic primary DENV3 illness in infants. At the time of symptomatic DENV3 infection, essentially all infants had low anti-DENV3 neutralizing activity (50% plaque reduction neutralizing titers [PRNT(50)] CONCLUSIONS: This prospective nested case-control study of primarily DENV3 infections during infancy has shown that infants exhibit a full range of disease severity after primary DENV infections. The results support an initial in vivo protective role for maternally derived antibody, and suggest that a DENV3 PRNT(50) >50 is associated with protection from symptomatic DENV3 illness. We did not find a significant association between DENV3 ADE activity at illness onset and the development of DHF compared with less severe symptomatic illness. The results of this study should encourage rethinking or refinement of the current ADE pathogenesis model for infant DHF and stimulate new directions of research into mechanisms responsible for the development of DHF during infancy. TRIAL REGISTRATION: ClinicalTrials.gov NCT00377754

INTRODUCTION: Adherence to urate-lowering drugs (ULDs) has not been well evaluated among those with gout. Our aim was to assess the level and determinants of non-adherence with ULDs prescribed for gout. METHODS: We identified persons using two integrated delivery systems aged 18 years or older with a diagnosis of gout who initiated use of allopurinol, probenecid or sulfinpyrazone from 1 January 2000 to 30 June 2006. Non-adherence was measured using the medication possession ratio (MPR) over the first year of therapy and defined as an MPR < 0.8. Descriptive statistics were calculated and logistic regression was used to estimate the strength of the association between patient characteristics and non-adherence. RESULTS: A total of 4,166 gout patients initiated ULDs; 97% received allopurinol. Median MPR for any ULD use was 0.68 (interquartile range (IQR) 0.64). Over half of the patients (56%) were non-adherent (MPR < 0.8). In adjusted analyses, predictors of poor adherence included younger age (odds ratio (OR) 2.43, 95% confidence interval (CI) 1.86 to 3.18 for ages <45 and OR 1.44, 95% CI 1.08 to 1.93 for ages 45 to 49), fewer comorbid conditions (OR 1.46, 95% CI 1.20 to 1.77), no provider visits for gout prior to urate-lowering drug initiation (OR 1.28, 95% CI 1.05 to 1.55), and use of non-steroidal anti-inflammatory drugs in the year prior to urate-lowering drug initiation (OR 1.15, 95% CI 1.00 to 1.31). CONCLUSIONS: Non-adherence amongst gout patients initiating ULDs is exceedingly common, particularly in younger patients with less comorbidity and no provider visits for gout prior to ULD initiation. Providers should be aware of the magnitude of non-adherence with ULDs.

Alzheimer's disease (AD) is an increasing epidemic threatening public health. Both men and women are susceptible to the disease although women are at a slightly higher risk. The prevalence of AD rises exponentially in elderly people from 1% at age of 65 to approximately 40%-50% by the age of 95. While the cause of the disease has not been fully understood, genetics plays a role in the onset of the disease. Mutations in three genes (APP, PSEN1, and PSEN2) have been found to cause AD and APOE4 allele increases the risk of the disease. As human genomic research progresses, more genes have been identified and linked with AD. Genetic screening tests for persons at high risk of AD are currently available and may help them as well as their families better prepare for a later life with AD.

To study procedural learning changes in patients with non-demented Parkinson disease (PD) but without depression. The Nissen serial reaction time task (SRTT) software version II (as a task of procedural learning), the Wechsler Memory Scale-Chinese version (WMS-CR), and two tasks of implicit memory were applied to 20 PD patients with a Hoehn-Yahr score at I-II degrees and 20 matched healthy controls were enrolled for the Nissen Version test. In the explicit WMS-CR and the implicit (word stem completion and degraded picture naming) tasks, the patients' scores fell within normal limits. In the SRTT, healthy controls displayed significantly reduced response times and error rates across the blocks of repeated sequence trials. In contrast, PD patients only showed a reduction in error rates but no change in response times. Impairment of nigrostriatal pathways selectively affects the performance in visuo-motor learning tasks such as the SRTT, but not in both the explicit tasks of WMS-CR and the implicit tasks.

STUDY OBJECTIVE: To compare drug adherence rates among patients with gout, hypercholesterolemia, hypertension, hypothyroidism, osteoporosis, seizure disorders, and type 2 diabetes mellitus by using a standardized approach. DESIGN: Longitudinal study. DATA SOURCE: Health care claims data from 2001-2004. PATIENTS: A total of 706,032 adults aged 18 years or older with at least one of the seven medical conditions and with incident use of drug therapy for that condition. MEASUREMENTS AND MAIN RESULTS: Drug adherence was measured as the sum of the days' supply of drug therapy over the first year observed. Covariates were age, sex, geographic residence, type of health plan, and a comorbidity score calculated by using the Hierarchical Condition Categories risk adjuster. Bivariate statistics and stratification analyses were used to assess unadjusted means and frequency distributions. Sample sizes ranged from 4984 subjects for seizure disorders to 457,395 for hypertension. During the first year of drug therapy, 72.3% of individuals with hypertension achieved adherence rates of 80% or better compared with 68.4%, 65.4%, 60.8%, 54.6%, 51.2%, or 36.8% for those with hypothyroidism, type 2 diabetes, seizure disorders, hypercholesterolemia, osteoporosis, or gout, respectively. Age younger than 60 years was associated with lower adherence across all diseases except seizure disorders. Comorbidity burden and adherence varied by disease. As comorbidity increased, adherence among subjects with osteoporosis decreased, whereas adherence among those with hypertension, hypercholesterolemia, or gout increased. Add-on drug therapies and previous experience with taking drugs for the condition increased adherence among subjects with hypertension, type 2 diabetes, hypothyroidism, or seizure disorders but not the other conditions. CONCLUSION: This uniform comparison of drug adherence revealed modest variation across six of seven diseases, with the outlier condition being gout.

BACKGROUND: Although rates of survival for women with breast cancer have improved, the survival disparity between African American and white women in the United States has increased. PURPOSE: To determine whether this survival disparity persists in an insured population with access to medical care. METHODS: In this retrospective cohort study, we extracted data from the tumor registries of six nonprofit, integrated health care delivery systems affiliated with the Cancer Research Network and assessed the survival of African American (n = 2276) and white (n = 18 879) female enrollees who were diagnosed with invasive breast cancer from January 1, 1993, through December 31, 1998. Cox proportional hazards regression was used to estimate the death rate among African American women relative to that of white women after adjustment for potential explanatory factors including stage at diagnosis, tumor characteristics, and treatment. RESULTS: Five-year survival was lower for African American women (73.8%) than for white women (81.6%). African American women were less likely to have tumor characteristics with good prognosis. Controlling for age at diagnosis, stage, grade, tumor size, and estrogen and progesterone receptor status, the adjusted hazard rate ratio for African American women was 1.34 (95% confidence interval = 1.22 to 1.46). Similar risks were found among women ages 20-49 and 50 and older. Controlling for treatment slightly lowered the hazard rate ratio to 1.31 (95% confidence interval = 1.20 to 1.43). CONCLUSIONS: Among women with invasive breast cancer, being insured and having access to medical care does not eliminate the survival disparity for African American women.

OBJECTIVES: To evaluate composite measures of response without acute-phase reactants in RA patients. Specifically, Clinical Disease Activity Index (CDAI)-derived response criteria were compared with the European League Against Rheumatism (EULAR) response criteria, and the modified ACR (mACR) response criteria were compared to the ACR response criteria. METHODS: Data from 10 108 RA patients enrolled in the Consortium of Rheumatology Researchers of North America registry were examined, including 649 patients initiating DMARD therapy. CDAI cut-off points for disease activity levels and responses were derived using receiver operating characteristic curves with the DAS28 and EULAR response criteria as gold standards. The kappa-statistics were applied to assess agreement between CDAI-derived and EULAR-defined responses, as well as ACR20 and ACR50 with mACR20- and mACR50-defined responses, respectively. RESULTS: For the components of the EULAR response, the derived CDAI cut-off points for DAS28 levels of 3.2 and 5.1 were 7.6 and 19.6, respectively. The derived CDAI cut-off points were 4.3 and 10.0 for DAS28 changes of 0.6 and 1.2, respectively. There were moderate to substantial agreements between CDAI-derived and EULAR responses (kappa = 0.57-0.71). Agreement of ACR20 and ACR50 with mACR20 and mACR50 responses, respectively, was excellent (kappa = 0.88-0.95). CONCLUSIONS: Agreement between composite measures of response without acute-phase reactants and standard measures ranged from moderate to excellent. The mACR20 and mACR50 criteria as well as CDAI-derived response criteria, can serve as composite measures of response in clinical practice and research settings without access to acute-phase reactants.

The genetic linkage of coronary artery disease is well-established. However, the transmission of this disease is not clearly defined. Although the Mendelian autosomal dominant pattern has been seen in familial hypercholesterolemia and mutant MEF2A induced familiar myocardial infarction, and a multifactorial genetic model has been proposed for non-familial CAD, the gender difference in this disease is not well explained. We hypothesized that CAD is a multifactorial inherited disorder with a sex-influenced trait, which shows an autosomal dominant pattern in men and autosomal recessive transmission in women. This hypothesis is supported by the facts including an age-dependent higher prevalence in men, the autosomal locations of CAD associated genes, the gender difference seen even in familiar CAD, and the potential gene-gene interactions between CAD associated genes on autosomal chromosomes and those found on the X chromosome. Further investigation of genetic components will provide not only the critical information about the etiology of CAD, but also help to clarify the confusion in the use of exogenous female hormones in the prevention and/or the treatment of the disease.

AIMS: To assess mortality after drug-eluting stent (DES) or bare-metal stent (BMS) for ST-segment elevation myocardial infarction (STEMI). METHODS AND RESULTS: In this multinational registry, 5093 STEMI patients received a stent: 1313 (26%) a DES and 3780 (74%) only BMS. Groups differed in baseline characteristics, type, or timing of percutaneous coronary intervention, with a higher baseline risk for patients receiving BMS. Two-year follow-up was available in 55 and 60% of the eligible BMS and DES patients, respectively. Unadjusted mortality was lower during hospitalization, similar for the first 6 months after discharge, and higher from 6 months to 2 years, for DES patients compared with that of BMS patients. Overall, unadjusted 2-year mortality was 5.3 vs. 3.9% for BMS vs. DES patients (P = 0.04). In propensity- and risk-adjusted survival analyses (Cox model), post-discharge mortality was not different up to 6 months (P = 0.21) or 1 year (P = 0.34). Late post-discharge mortality was higher in DES patients from 6 months to 2 years (HR 4.90, P = 0.01) or from 1 to 2 years (HR 7.06, P = 0.02). Similar results were observed when factoring in hospital mortality. CONCLUSION: The observation of increased late mortality with DES vs. BMS suggests that DES should probably be avoided in STEMI, until more long-term data become available.

BACKGROUND: The accessibility of tobacco for youth is difficult to measure, partly because of the varied sources of cigarettes. Perceptions about the accessibility of cigarettes assesses availability from all potential sources and has been found to predict future smoking. This study examines the determinants of perceived accessibility from the perspective of a longitudinal study. METHODS: Data were derived from the second Development and Assessment of Nicotine Dependence in Youth study, a 4-year longitudinal study of 1246 sixth-grade students who underwent up to 11 in-person interviews from 2002 to 2006. Perceived accessibility was assessed prospectively by asking students whether they agreed or disagreed with the statement It would be easy for me to get a cigarette. RESULTS: At baseline, the average age was 12 years; 85% had never before smoked; more than 21% perceived that cigarettes were easy to obtain. Perceived accessibility increased over the 4 years among the cohort. Youth with friends who smoked or whose parents allowed the watching of R-rated movies were more likely to perceive easy accessibility of cigarettes. Among nonsmokers, there was a dose-response relationship between perceived accessibility and exposure to smoking in the family environment. Nonsmokers who knew commercial sources of cigarettes also had higher perceived accessibility. CONCLUSIONS: Several potentially preventable exposures to tobacco in the family and social environment contribute to confidence among some youth that cigarettes are easy to obtain. Further studies are needed to determine if modifying these factors (e.g., through programs to reduce the exposure of youth to tobacco products in the home) might reduce perceived accessibility.