Retention of "safe" blood donors. The Retrovirus Epidemiology Donor Study

BACKGROUND: There are obvious advantages to increasing donor retention. However, for reasons of blood safety, certain donors may, in fact, be more desirable to retain than others. “Safe” donors are defined as those who provided a blood donation that was negative on all laboratory screening tests and who subsequently reported no behavioral risks in response to an anonymous survey. This study identifies the most important factors affecting the intention of “safe” donors to provide another donation. STUDY DESIGN AND METHODS: An anonymous survey asking about donation history, sexual history, injecting drug use, and recent donation experience was mailed to 50,162 randomly selected allogeneic donors (including directed donors) who gave blood from April through July or from October through December 1993 at one of the five United States blood centers participating in the Retrovirus Epidemiology Donor Study. Before mailing, questionnaires were coded to designate donors with nonreactive laboratory screening tests at their most recent donation. RESULTS: A total of 34,726 donors (69%) responded, with substantially higher response among repeat donors. According to reported intentions only, the vast majority of “safe” donors indicated a high likelihood of donating again within the next 12 months. Only 3.4 percent reported a low likelihood of donating again. A comparison of those likely to return and those unlikely to return reveals significant differences in demographics and in ratings of the donation experience. A higher proportion of those unlikely to return were first-time donors, minority-group donors, and donors with less education. The highest projected loss among “safe” donors was seen for those who gave a fair to poor assessment of their treatment by blood center staff or of their physical well-being during or after donating. CONCLUSION: These data suggest that efforts to improve donors' perceptions of their donation experience, as well as attention to the physical effects of blood donation, may aid in the retention of both repeat and first-time donors.     

Performance characteristics of HIV-1 culture and HIV-1 DNA and RNA amplification assays for early diagnosis of perinatal HIV-1 infection

A plasma HIV-1 RNA amplification assay (RNA assay), a quantitative peripheral blood mononuclear cell (PBMC) microculture (culture), and a PBMC HIV-1 DNA amplification assay (DNA assay) were compared for diagnosis of HIV-1 infection in infants receiving zidovudine in Pediatric AIDS Clinical Trials Group protocol 185; assays were performed for all 24 infected and 100 uninfected infants. HIV-1 infection was defined as >or=2 positive cultures or positive antibody to HIV-1 at >or=18 months. Cultures were performed at birth and 6 and 24 weeks of age; DNA and RNA assays were performed on cryopreserved specimens. The sensitivity of culture and DNA and RNA assays at birth was 20.8%, 10.5%, and 26.7%, respectively. At older ages, sensitivity typically exceeded 80%, remaining highest for the RNA assay (>85%). Assay specificity was >99%. Positive predictive values exceeded 93% for each assay at each age; negative predictive values were highest (>90%) for the RNA assay. At birth (P < 0.005) and age 6 weeks (P < 0.001), a significantly larger proportion of infected infants were identified by means of the RNA assay than by the other assays. The diagnostic performance of the RNA assay matched or exceeded that of culture and the DNA assay. Given that RNA assays require less blood volume and yield rapid results, our study adds to existing data suggesting that RNA assays may be used for early diagnosis of HIV-1 infection in infants.     

Urinary Tract Stones and Osteoporosis: Findings From the Women's Health Initiative

Kidney and bladder stones (urinary tract stones) and osteoporosis are prevalent, serious conditions for postmenopausal women. Men with kidney stones are at increased risk of osteoporosis; however, the relationship of urinary tract stones to osteoporosis in postmenopausal women has not been established. The purpose of this study was to determine whether urinary tract stones are an independent risk factor for changes in bone mineral density (BMD) and incident fractures in women in the Women's Health Initiative (WHI). Data were obtained from 150,689 women in the Observational Study and Clinical Trials of the WHI with information on urinary tract stones status: 9856 of these women reported urinary tract stones at baseline and/or incident urinary tract stones during follow‐up. Cox regression models were used to determine the association of urinary tract stones with incident fractures and linear mixed models were used to investigate the relationship of urinary tract stones with changes in BMD that occurred during WHI. Follow‐up was over an average of 8 years. Models were adjusted for demographic and clinical factors, medication use, and dietary histories. In unadjusted models there was a significant association of urinary tract stones with incident total fractures (HR 1.10; 95% CI, 1.04 to 1.17). However, in covariate adjusted analyses, urinary tract stones were not significantly related to changes in BMD at any skeletal site or to incident fractures. In conclusion, urinary tract stones in postmenopausal women are not an independent risk factor for osteoporosis. © 2015 American Society for Bone and Mineral Research.     

Effect of exercise rate and route of inhalation on sulfur-dioxide-induced bronchoconstriction in asthmatic subjects

Nine asthmatic subjects exercised at low, moderate, and high work rates on a cycle ergometer while breathing filtered, humidified air with or without 0.5 ppm of sulfur dioxide (SO2) in a double-blind study. Subjects first performed these experiments breathing through a mouthpiece while wearing a noseclip (oral breathing) and then repeated the experiments breathing through a facemask that separated and permitted independent measurement of oral and nasal air flow (oronasal breathing). We determined specific airway resistance before and after exercise by body plethysmography. Inhaled by mouthpiece, 0.5 ppm So2 caused bronchoconstriction at moderate and high but not at low work rates. There was a dose-response relationship between the work rate performed and the degree of bronchoconstriction induced. Inhaled oronasally, 0.5 ppm SO2 caused bronchoconstriction only at the high work rate. These findings demonstrate that So2-induced bronchoconstriction is dependent on the work rate of exercise during exposure, that oronasal breathing is only partially effective in preventing the bronchoconstriction observed with oral breathing, and that oronasal breathing is less effective in preventing bronchoconstriction with high than with moderate exercise at this concentration of SO2.     

Effectiveness of mealtime interventions on nutritional outcomes for the elderly living in residential care: A systematic review and meta-analysis

The need to improve the nutrition of the elderly living in long term care has long been recognised, but how this can best be achieved, and whether (and which) intervention is successful in reducing morbidity is less well understood. The aim of this systematic review was to determine the effectiveness of mealtime interventions for the elderly living in residential care. Mealtime interventions were considered as those that aimed to change/improve the mealtime routine, practice, experience or environment. Following comprehensive searches, review and appraisal, 37 articles were included. Inadequate reporting in over half of the articles limited data quality appraisal. Mealtime interventions were categorised into five types: changes to food service, food improvement, dining environment alteration, staff training and feeding assistance. Meta-analysis found inconsistent evidence of effects on body weight of changes to food service (0.5 kg; 95% CI: ?1.1 to 2.2; p = 0.51), food improvement interventions (0.4 kg; 95% CI: ?0.8 to 1.7; p = 0.50) or alterations to dining environment (1.5 kg; 95% CI: ?0.7 to 2.8; p = 0.23). Findings from observational studies within these intervention types were mixed, but generally positive. Observational studies also found positive effects on food/caloric intake across all intervention types, though meta-analyses of randomised studies showed little evidence of any effects on food/caloric intake in food improvement studies (?5 kcal; 95% CI: ?36 to 26; p = 0.74). There was some evidence of an effect on daily energy intakes within dining environment studies (181 kcal/day, 95% CI: ?5 to 367, p = 0.06). The need to improve the nutrition of the elderly living in residential long term care is well recognised. This review found some evidence that simple intervention around various aspects of mealtime practices and the mealtime environment can result in favourable nutritional outcomes. Further large scale pragmatic trials, however, are still required to establish full efficacy of such interventions.     

Risk factors for osteoporotic fractures in persons with spinal cord injuries and disorders

Summary

Clinical risk factors for fracture were explored among Veterans with a spinal cord injury. At the end of 11 years of follow-up, the absolute risk of fracture was approximately 20 %. Among the clinical and SCI-related factors explored, a prior history of fracture was strongly associated with incident fracture.

Introduction

Few studies to date have comprehensively addressed clinical risk factors for fracture in persons with spinal cord injury (SCI). The purpose of this study was to identify risk factors for incident osteoporotic fractures in persons with a SCI that can be easily determined at the point of care.

Methods

The Veteran’s Affairs Spinal Cord Dysfunction Registry, a national database of persons with a SCI, was used to examine clinical and SCI-related risk factors for fracture. Incident fractures were identified in a cohort of persons with chronic SCI, defined as SCI present for at least 2 years. Cox regression models were used to estimate the risk of incident fractures.

Results

There were 22,516 persons with chronic SCI included in the cohort with 3365 incident fractures. The mean observational follow-up time for the overall sample was 6.2 years (median 6.0, IQR 2.9–11.0). The mean observational follow-up time for the fracture group was 3.9 years (median 3.3, IQR 1.4–6.1) and 6.7 years (median 6.7, IQR 3.1–11.0) for the nonfracture group. By the end of the study, which included predominantly older Veterans with a SCI observed for a relatively short period of time, the absolute (i.e., cumulative hazard) for incident fractures was 0.17 (95%CI 0.14–0.21). In multivariable analysis, factors associated with an increased risk of fracture included White race, traumatic etiology of SCI, paraplegia, complete extent of SCI, longer duration of SCI, use of anticonvulsants and opioids, prevalent fractures, and higher Charlson Comorbidity Indices. Women aged 50 and older were also at higher risk of sustaining an incident fracture at any time during the 11-year follow-up period.

Conclusions

There are multiple clinical and SCI-related risk factors which can be used to predict fracture in persons with a SCI. Clinicians should be particularly concerned about incident fracture risk in persons with a SCI who have had a previous fracture.

     

Adherence to guidelines and its effects on hospitalizations with complications of type 2 diabetes

OBJECTIVES: To study the discrepancy between actual and recommended rates of use among several measures of screening for complications of diabetes in a national longitudinal sample, the correlations among measures of adherence, and whether or not higher rates of adherence reduce hospitalizations for complications of diabetes. The key study hypothesis was that lack of adherence to professional recommendations for diabetes care leads to adverse health outcomes for elderly persons. METHODS: Administrative claims and survey data for 1994-­1999 on a nationally representative sample of Medicare beneficiaries age 65+. Principal components analysis and instrumental variables probit regression methods were used. RESULTS: Most Medicare beneficiaries diagnosed with type 2 diabetes had at least one physician visit per year, but rates of screening (eye examinations and HbA1c, lipid, microalbumin and urine tests) fell far short of recommendations. Correlations among use rates for various types of screening were positive but far less than one, suggesting that failure to screen reflects a complex set of underlying factors. Increased rates of adherence were observed for HbA1c and lipid testing over the observation period. Higher use was associated with lower rates of hospitalization for complications of diabetes (vascular (p=0.007), renal (p=0.002), and other complication (p=0.005)). CONCLUSIONS: Adherence to guidelines was associated with significantly reduced rates of hospitalization. Continued analysis of the trends in clinical practice is needed to demonstrate the effectiveness of standardized guidelines for the care of patients with diabetes.     

Role of lifestyle and oral anti-diabetic agents to prevent type 2 diabetes mellitus and cardiovascular disease

Patients with type 2 diabetes mellitus (DM) and those with impaired glucose tolerance are at increased risk for the development of cardiovascular disease. With an increasing global incidence and prevalence of type 2 DM, and with the 2003 lowering of the glucose threshold required for the diagnosis of impaired glucose tolerance to 100 mg/dl (5.6 mmol/L), the concept of DM prevention, and presumed reduction of cardiovascular risk, is attractive. However, there is little evidence to guide the choice of DM prevention strategy and no certainty that DM prevention will result in reduced cardiovascular events or an overall favorable balance of benefit to risk. In conclusion, this review examines previous reports on DM prevention, with special attention to evidence for cardiovascular event reduction in association with specific interventions to prevent DM.     

Cardiovascular effects at multi-detector row CT colonography compared with those at conventional endoscopy of the colon

PURPOSE: To compare the cardiovascular effects of computed tomographic (CT) colonography and conventional endoscopy in a group of patients undergoing both procedures. MATERIALS AND METHODS: A total of 144 patients underwent CT colonography followed by flexible sigmoidoscopy (40 patients) or colonoscopy (104 patients). Pulse, blood pressure, and oxygen saturation were measured before, during, and after the procedures. Forty patients also underwent continuous Holter electrocardiographic (ECG) monitoring. Periprocedural pain was assessed by using a handheld counting device. Outcome variables were assessed by using a combination of paired t testing and multilevel linear regression. RESULTS: When a spasmolytic was not used, CT colonography was associated with only a small increase in oxygen saturation (P =.03), while use of a spasmolytic caused an increase in pulse (mean increase, 19.9 beats per minute; P <.001) and diastolic blood pressure (mean increase, 5 mm Hg; P <.001). Compared with that at CT, oxygen saturation decreased significantly during and after colonoscopy and sigmoidoscopy (mean decrease after colonoscopy with sedation, 1.0%; P <.001). Systolic and diastolic blood pressure also decreased during and after colonoscopy (mean systolic decrease after colonoscopy with sedation, 16.6 mm Hg, P <.001; mean diastolic decrease after colonoscopy with sedation, 7.5 mm Hg, P <.001). Patients were 30.3 times more likely to develop bradycardia after endoscopy (95% CI: 2.65, 346; P =.006). Ventricular couplets were significantly higher at endoscopy than at CT in patients with a history of cardiac disease (odds ratio: 72.5 and 95% CI: 4.56, 1,153 at CT vs odds ratio: 14.6 and 95% CI: 0.96, 222 at endoscopy; P =.002). Patients were 1.89 times more likely to register pain during colonoscopy than during CT (95% CI: 1.06, 3.38; P =.03). CONCLUSION: CT colonography had no significant cardiovascular effect other than spasmolytic-induced tachycardia. Endoscopy-and colonoscopy in particular-causes cardiovascular effects that are largely related to sedation. CT colonography is less painful than colonoscopy and is comparable to flexible sigmoidoscopy.