Impact of hormone therapy on false-positive recall and costs among women undergoing screening mammography

OBJECTIVE: We sought to evaluate the effects of hormone therapy (HT) on false-positive (FP) recall for additional breast evaluation and costs. DESIGN: We undertook an observational cohort study of women ages 40-80 years with 2 mammography screenings in an integrated delivery system. MEASURES: FP recall, defined as mammograms resulting in a radiologist's recommendation for additional imaging, ultrasound, or invasive procedures among disease-free women, was compared for nonusers, initiators, discontinuers, and continuers of HT. Differences in health care costs by HT were assessed for total, primary care, specialty, laboratory, radiology, inpatient, mental health, and pharmacy. RESULTS: There was no association between HT and FP recall among women ages 40-49 years. Among women 50 years or older, current HT users, ie, initiators and continuers, had increased odds of FP recall (odds ratio; 95% confidence interval) compared with nonusers (1.2; 1.0-1.4 for women 50-59 years; 1.8; 1.5-2.2 for women 60-69; and 1.7; 1.4-2.0 for women 70-80 years). Among women 50-59 years, the odds of FP recall were attributed to opposed HT (ie, estrogen+progestin). Increases in FP recall among HT users 60 years and older was maintained for initiators, continuers, opposed, and unopposed (estrogen only). Increases in FP recall among HT users were for imaging and ultrasound but not invasive procedures. Costs for current HT users during the 12 months after screening were not higher than nonusers, except for pharmacy and outpatient mental health. CONCLUSION: The relationship between HT use and FP recall is greatest among older women and does not result in a differential use of invasive procedures.     

Synthesis, spectra, delivery and potentiometric responses of new styryl dyes with extended spectral ranges

Styryl dyes have been among the most widely used probes for mapping membrane potential changes in excitable cells. However, their utility has been somewhat limited because their excitation wavelengths have been restricted to the 450-550 nm range. Longer wavelength probes can minimize interference from endogenous chromophores and, because of decreased light scattering, improve recording from deep within tissue. In this paper we report on our efforts to develop new potentiometric styryl dyes that have excitation wavelengths ranging above 700 nm and emission spectra out to 900 nm. We have prepared and characterized dyes based on 47 variants of the styryl chromophores. Voltage-dependent spectral changes have been recorded for these dyes in a model lipid bilayer and from lobster nerves. The voltage sensitivities of the fluorescence of many of these new potentiometric indicators are as good as those of the widely used ANEP series of probes. In addition, because some of the dyes are often poorly water soluble, we have developed cyclodextrin complexes of the dyes to serve as efficient delivery vehicles. These dyes promise to enable new experimental paradigms for in vivo imaging of membrane potential.     

Risk factors for initiation into drug injection among adolescent street youth

Young injectors are a group with high-risk behaviours, particularly with respect to HIV infection and hepatitis C. A leading strategy to prevent these infections could be the prevention of injection, especially among the youngest individuals. We report analyses on initiation into drug injection from a prospective cohort study of street youth conducted in Montreal, Canada. Among 118 non-injector participants under 18 years of age followed for an average of 1.31 years, we estimated an incidence rate of injection of 22.7 per 100 person-years. Independent predictors of initiation were: a lifetime history of use of ≥4 types of drugs, recent daily alcohol drinking, a recent episode of homelessness, a lifetime history of rape, and recent involvement in survival sex. The observed high rate of initiation into injection clearly indicates that interventions to prevent injection should target especially adolescent street youth. These interventions should address simultaneously individual and structural factors, such as substance abuse and living conditions.     

Computer tailoring: a potential solution for optimizing prevention counseling

Scientific literature shows that physicians who engage in clinical prevention practices (CPP) have an influence on population health. This is why they are encouraged to apply such practices to promote healthy lifestyle habits in their patients, such as exercise, a healthy diet, and smoking cessation. However, as revealed in a recent study published in the Canadian journal of Public Health, lack of time is the main barrier for doctors in applying CPP. Following upon the results presented in their study, the authors suggest certain solutions that are likely to facilitate prevention practices. The goal of this commentary is to familiarize readers with another potential solution, relatively unknown in Canada, namely computer-tailoring. This innovative intervention method has the potential to facilitate prevention counselling because it provides a means of interacting with a large audience by formulating "customized" educational messages for each member.     

Immunogenicity and safety of an inactivated Rift Valley fever vaccine in a 19-year study

An investigational, formalin-inactivated Rift Valley fever (RVF) vaccine, known as The Salk Institute-Government Services Division (TSI-GSD) 200 vaccine, was administered to 1860 at-risk subjects (5954 doses) between 1986 and 2004 as a three-dose primary series (days 0, 7, and 28) followed by booster doses as needed for declining titers. An initial positive serological response (PRNT₈₀ ≥ 1:40) to the primary series was observed in 90% of subjects. Estimate of the PRNT₈₀ response half-life in initial responders to the primary series by Kaplan-Meier plot was 315 days after the primary series dose 3. Differences in a serological response were observed at 2 weeks after dose 3 of the primary series between vaccine lots and for gender (women > men); a trend was observed for age (<40 years). When response to the primary series was measured by PRNT₅₀ titer ≥1:40, nearly all subjects (99.1%) responded. In individuals not initially responding to the primary series (PRNT₈₀ < 1:40), a response was observed in most subjects after receiving only one booster dose. Immune response (all subjects) to subsequent booster doses for a declining titer (PRNT₈₀ < 1:40) was 98.4%. The vaccine was well-tolerated; vaccine-related adverse reactions were generally mild and self-limited. Differences in adverse events were observed with vaccine lot and sex. The data support the safety and immunogenicity of the inactivated RVF vaccine, and may serve as a standard of comparison for immunogenicity and safety for future RVF vaccines.     

Markers of inflammation in prevalent and incident Parkinson's disease in the Cardiovascular Health Study

BackgroundStudies demonstrate existence of inflammation in prevalent Parkinson’s disease (PD). We assessed associations of baseline levels of inflammatory markers with prevalent PD at baseline (1989) and incident PD identified over 13 years of follow-up of the Cardiovascular Health Study.MethodsBlood samples at baseline were measured for fibrinogen, interleukin-6, tumor necrosis factor-α, C-reactive protein, albumin, and white blood cells. The analysis included 60 prevalent and 154 incident PD cases.ResultsRisk of prevalent PD was significantly higher per doubling of IL-6 among women (odds ratio [OR] = 1.5, 95% confidence interval [CI]: 1.0, 2.4) and WBC among men (OR: 2.4, 95% CI: 1.2, 4.9) in multivariate models. Risk of incident PD was not associated with higher levels of any biomarker after adjusting for age, smoking, African American race, and history of diabetes. Inverse associations with incident PD were observed per doubling of C-reactive protein (OR = 0.9; 95% CI: 0.8, 1.0) and of fibrinogen among women (OR = 0.4; 95% CI: 0.2, 0.8).ConclusionsAlthough inflammation exists in PD, it may not represent an etiologic factor. Our findings suggest the need for larger studies that measure inflammatory markers before PD onset.