Absence Of Specific Interventions Research Articles

Transfusion-associated graft-versus-host disease, transfusion-associated hyperkalemia, and potassium filtration: advancing safety and sufficiency of the blood supply

Irradiation of cellular blood components is well established as a countermeasure against transfusion-associated graft-versus-host disease (TA-GVHD). Unintended consequences of ionizing radiation are also well established. The red cell “storage lesion” – a progression of metabolic, functional, and morphological changes – may be exacerbated by irradiation rates and doses typically used for TA-GVHD prophylaxis. With or without irradiation, a storage lesion change of clinical concern is the accelerated egress of intracellular potassium. ATP depletion during storage limits the activity of the red cell membrane’s sodium-potassium pump (Na,K-ATPase), which normally maintains intracellular potassium (K+) at levels 30–40 times higher than the extracellular milieu. The natural diffusion of potassium down this concentration gradient proceeds faster if the cell membrane is damaged, and oxidative damage to cellular membranes and membrane proteins – including Na,K-ATPase – is an effect of ionizing radiation.Preventing transfusion-related hyperkalemia is a reason for limiting the shelf life of irradiated red cells. In the absence of specific measurements to assess storage lesion in a particular unit of blood, and in the absence of specific interventions at the time of transfusion to mitigate effects of storage lesion, it is consistent with the precautionary principle to put conservative limits on a blood component’s shelf life. On the other hand, both the safety and sufficiency of a nation’s blood supply might be improved by interventions that benefit specific recipients when they are transfused, and benefit future patients by extending the allowable shelf life of blood components. Potassium filtration of irradiated red blood cell components is one such intervention.

Natural rates of teacher praise in the classroom: A systematic review of observational studies

AbstractPrevious research documents the positive impacts that teacher praise can have on students' behavior in the classroom; positive praise is a reinforcer that improves and maintains appropriate classroom behavior. Identifying current trends in natural rates of praise—praise that occurs in the absence of specific intervention or training—may help teachers become mindful of their own practices. The purpose of this systematic review was to investigate characteristics of published observational studies of teacher‐delivered praise and identify the rate at which teachers delivered praise. We conducted a systematic search of the literature, and included studies published after 2004; 14 studies met our inclusion criteria. The results of this study illustrate that researchers use several different measures to observe and report the frequency of teacher praise. Teachers also delivered general praise (range = 0.04 per min to 67.9 per hour) and behavior‐specific praise (range = 5.9–23.14 per hour) at widely variable rates. Teachers commonly used more general praise compared with behavior‐specific praise. Across studies, we also found inconsistent rates of teacher praise versus reprimands, with some studies reporting higher rates of praise while other studies reported higher rates of reprimands. We discuss implications for teachers and provide recommendations for future research.

Author Response: Temporal Trends and Autopsy Findings of SUDEP Based on Medicolegal Investigations in the United States

We thank Dr. Bleasel for his interest in our study.1 We, too, were encouraged to find that the incidence of SUDEP may be declining even in the absence of specific interventions. This confirms what many people caring for people with epilepsy suspected—we have many of the tools to reduce epilepsy mortality already at hand. The next steps are to understand the contribution of each of the measures that Dr. Bleasel highlights—awareness, clinician and patient behavior change, and access to treatment—to the reduction in SUDEP rates to maximize their effect. We also agree—as do people living with epilepsy and their caregivers,2,3 those bereaved by SUDEP,4 and professional societies5—that counseling about SUDEP should be part of general epilepsy education regardless of individual risk to help our patients make fully informed decisions.

Smoking behaviour before, during, and after pregnancy: the effect of breastfeeding.

Data for this study were obtained from a population-based follow-up study in 25 Italian Local Health Units (LHUs) to evaluate pregnancy, delivery, and postpartum care in Italy. A sample of 3534 women was recruited and interviewed within a few days of their giving birth and at 3, 6, and 12 months after delivery, by trained interviewers using questionnaires. The objective of the study was to evaluate changes in smoking behaviour from one interview to the next. Of 2546 women who completed the follow-up, smoking prevalences before and during pregnancy were 21.6% and 6.7%; smoking prevalences and smoking relapse at 3, 6, and 12 months were 8.1% and 18.5%, 10.3% and 30.3%, and 10.9% and 32.3%, respectively. Smoking during and after pregnancy was more likely among women who were less educated, single, not attending antenatal classes, employed, and not breastfeeding. The results show that women who are breastfeeding smoke less than not breastfeeding women, even after controlling for other predictors (i.e., smoking relapse at 12 months: OR = 0.43, 95% CI: 0.19, 0.94). A low maternal mood increases the risk of smoking relapse within 6 months of about 73%. This study also suggests that prolonged breastfeeding reduces the risk of smoking relapse and that this reduction may be persistent in time. Interventions targeting breastfeeding promotion may also indirectly support smoking cessation, even in absence of specific interventions.

Epidemiology of HIV infection in the newborn.

Vertical transmission of HIV infection can take place in utero, during delivery and postnatally through breastfeeding, with about three-quarters of infections occurring around the time of delivery in non-breastfeeding populations. In Europe, in the absence of specific interventions, the vertical transmission rate was 15-20%. High maternal load is the major risk factor for both intra-uterine and intra-partum mother-to-child transmission. Prematurity is the most common adverse neonatal outcome associated with maternal HIV infection. Earlier diagnosis of paediatric HIV infection than previously available is now possible with virological tests, particularly HIV DNA polymerase chain reaction. An estimated one fifth of infected children will have been diagnosed with AIDS or have died by 12 months of age, rising to a third by 6 years of age. Surgical and therapeutic interventions are effective in reducing vertical transmission risk, in addition to the avoidance of breastfeeding. Caesarean section delivery before labour and before rupture of membranes approximately halves the risk of transmission, while prophylactic zidovudine therapy according to the ACTG076 regimen reduces transmission by up to two-thirds, transmission is reduced even further with both interventions. Trials of short-course zidovudine regimens show their effectiveness in reducing vertical transmission, in breastfeeding and non-breastfeeding populations. Nevirapine has been shown to be significantly more effective than short course zidovudine regimens in breastfeeding populations, but is still under evaluation in non-breastfeeding populations additionally receiving routine anti-retroviral prophylaxis. Reports of a small number of serious adverse events in uninfected children exposed in utero or neonatally to antiretroviral therapy need further investigation. Trials of vitamin A supplementation to reduce vertical transmission have had negative results, while the effectiveness of vaginal lavage and passive immune therapy in reducing vertical transmission remains uncertain.

Genetic testing for breast-ovarian cancer susceptibility: a regional trial.

To evaluate receptivity to testing for a genetic susceptibility to breast-ovarian cancer, information is needed on the response when the offer is open to all qualifying women in a given region. To qualify in this trial, a woman who had not had breast or ovarian cancer had to have at least two first-degree relatives or one first- and one second-degree relative with breast and/or ovarian cancer, whereas a woman who had had breast or ovarian cancer had to have at least one first-degree relative with breast or ovarian cancer and a first- or second-degree relative without cancer willing to be tested. Of 140 women qualifying and interested enough to return questionnaires requesting baseline information, 111 were referred by their physician and 29 were identified from a regional tumor registry. Of these 140, 112 came for pretest education and 98 of these chose to be tested. Thus, the acceptance rate was 70% for all those returning baseline questionnaires, but 88% for those interested enough to come for pretest education. The most common reasons for accepting testing were to take extra precautions if a mutation were found (42.9%) and to determine if offspring were at risk (24.5%). The most common reasons for declining were anxiety and absence of specific interventions. Factors predicting who chose testing were years of education (p < 0.005) and family closeness (p < 0.02). Fourteen deleterious BRCA1 or BRCA2 mutations were found in 13 of the 87 families actually tested. If the criteria for testing had been three or more affected family members rather than two or more, the number of families tested would have been reduced by 46%, but the number of families found to have a deleterious mutation would have been reduced by only 9%.

Who should receive high-cost mental health treatment and for how long?

The use of some recently developed and promising mental health treatments is likely to be restricted by their high cost. Cost-effectiveness studies, however, suggest that high treatment costs may be offset by associated reductions in inpatient service use. In view of the considerable variation in the cost of inpatient treatment for the mentally ill, it may be cost-efficient to use high-cost treatments for frequent hospital users but not for others. To illustrate this principle, we examine 9-year trends in inpatient costs incurred by schizophrenia patients discharged from Department of Veterans' Affairs medical centers across the country in fiscal year (FY) 1982. Even in the absence of specific intervention, average inpatient costs in this sample fell 49 percent, from $7,368 per patient in FY 1983 to $3,770 per patient in FY 1990, reducing the potential for inpatient cost offsets over time. Sensitivity analyses of potential inpatient cost offsets were conducted using a range estimate both for the cost of treatment and for resulting reductions in inpatient expense. Assuming effectiveness in a middle range, high-cost intervention was projected to be cost-neutral for the 25 percent of the sample with the highest rates of baseline hospital use for a duration of 1-3 years. Although our specific model had low predictive power, the projection of cost offsets in large mental health systems deserves further examination and may prove to be one useful criterion, in addition to clinical effectiveness, for selecting patients to receive expensive treatment.