Maintenance energy requirements of beef cows and relationship with cow and calf performance, metabolic hormones, and functional proteins

Gestating Angus, nonlactating, spring-calving cows were used to determine variation in maintenance energy requirements (MR); to evaluate the relationship among MR and cow and calf performance, plasma concentrations of IGF-I, T4, glucose, insulin, and ruminal temperature; and to describe the LM proteome and evaluate protein abundance in cows with different MR. Cows (4 to 7 yr of age) with a BCS of 5.0 ± 0.2 and BW of 582 ± 37 kg in the second to third trimester of gestation were studied in 3 trials (trial 1, n = 23; trial 2, n = 32; trial 3, n = 38). Cows were individually fed a complete diet in amounts to meet predicted MR (Level 1 Model of NRC), and feed intake was adjusted weekly until constant BW was achieved for at least 21 d (maintenance). Cows were classified on the basis of MR as low (>0.5 SD less than mean, LMR), moderate (±0.5 SD of mean, MMR), or high (>0.5 SD more than mean, HMR) MR. Blood samples were taken at maintenance and at 2 mo postpartum in trial 2. Muscle biopsies were taken from LMR and HMR after cows consumed actual MR for 28 d (trial 2) or 21 d (trial 3). Proteins from LM were separated by 2-dimensional difference gel electrophoresis and were identified, and abundance was quantified and compared. The greatest differences in MR between cows were 29%, 24%, and 25% in trials 1, 2, and 3, respectively. Daily MR (NEm, kcal·BW(-0.75)·d(-1)) averaged 89.2 ± 6.3, 93.0 ± 4.9, and 90.4 ± 4.6 in trials 1, 2, and 3, respectively. Postpartum BW and BCS, calf birth and weaning weights, postpartum luteal activity, and ruminal temperature were not influenced by MR of the cows. Concentrations of IGF-I were greater (P = 0.001) in plasma of MMR compared with LMR cows consuming predicted MR diets, and MR was negatively correlated with concentrations of IGF-I in plasma (r = -0.38; P = 0.05) at 2 mo postpartum. A total of 103 proteins were isolated from LM; 52 gene products were identified. Abundance of specific proteins in the LM was not influenced (P > 0.11) by MR. Variation in MR of cows will make it possible to improve feed efficiency by selection. Identification of biomarkers for MR will allow selection of more efficient cows, which consume less feed and produce calves with similar weaning weights. Productive cows that require less feed for maintenance will improve efficiency of production and enhance sustainability of the environment.

142 EFFECT OF HIGH AND LOW ANTRAL FOLLICLE COUNT IN PUBERTAL BEEF HEIFERS ON IVF

Pubertal heifers can be classified between those with high (n = 25) or low (n = 15) antral follicle counts (AFC). The objective of this study was to determine oocyte development and maturation (e.g. fertility) in an IVF system for high- and low-AFC heifers. From a pool of 120 heifers, 10 high- and 10 low-AFC heifers were determined by transrectal ultrasonography; all heifers with evidence of oestrous cyclicity (i.e. pubertal) were synchronized with two 5-mL injections of prostaglandin F2α 11 days apart. Heifers were euthanized over 4 days on Days 15 to 16 of the synchronized oestrous cycle. A total of 15 heifers (n = 7 high and n = 8 low AFC) were at the appropriate stage of the oestrous cycle. Ovaries were collected and transported to the laboratory. Follicles less than 8 mm in diameter were aspirated. The IVF procedures and media were as previously described (Miles et al. 2004. Biol. Reprod. 71, 1919–1926). Cumulus-oocyte complexes (COC) were identified and washed in oocyte collection medium and then in maturation medium and were cultured (5% CO2; 38.5°C) for 24 h. Following maturation, COC were transferred and washed in fertilization medium. Thawed frozen semen from a crossbred bull was subjected to the swim-up procedure. Motile spermatozoa were collected and added to COC to yield a final concentration of spermatozoa per milliliter of fertilization medium. About 24 h later, presumptive zygotes were washed in development medium, placed in microdrops of development medium, and cultured for 8 days. On Days 3 and 8 after fertilization, cleavage and blastocyst development, respectively, were assessed. Data were analysed using the Proc Mixed procedure of SAS (SAS Institute Inc., Cary, NC, USA) and the model included the effects of day of collection (n = 4), group (n = 7 high- or n = 8 low-AFC heifers), and the interaction. The interaction did not differ (P = 0.10). Day of collection influenced (P < 0.05) the number of COC and the number of oocytes cleaved. High- compared to low-AFC heifers had the greater (P < 0.05) numbers of COC (42.7 ± 4.66 v. 22.1 ± 4.59), oocytes that cleaved (28.1 ± 3.60 v. 15.9 ± 3.55), and developed to blastocysts (13.2 ± 1.71 v. 6.2 ± 1.69). However, there was no difference (P > 0.10) in the percentage of COC that cleaved (65.3 ± 5.58 v. 66.2 ± 5.50%, high v. low, respectively) or that developed to blastocysts (46.7 ± 6.75 v. 42.2 ± 6.65%). In conclusion, AFC did not appear to affect oocyte maturation and development through the blastocyst stage.

79 UTERINE AND PLACENTAL INTERACTIONS DURING NECROTIC TIP DEVELOPMENT IN THE PIG FROM DAY 22 TO 42 OF GESTATION

Placental development is important for fetal development and nutrient and waste transport. The pig, a litter bearing animal, has an epitheliochorial placenta that forms a noninvasive attachment with the uterine endometrium. Insufficient placental development is one of the primary causes of fetal death and reduced fetal growth after 35 days of gestation. Necrotic tips develop at the distal ends of each allantochorion between Day 22 and 42 of gestation. During this same period, placenta attaches to the uterine endometrium and establish fetal blood supplies and nutrient exchange. The attached placenta is composed of a central highly vascular placental (HVP) region adjacent to the fetus and less vascular placental (LVP) regions on either side to the fetus, the paraplacenta and necrotic tips, which form after 27 days of gestation. The objective of this study was to comprehensively evaluate uterine–placental interactions and necrotic tip development from 22 to 42 days of gestation in the gilt. Gilts (n = 25) were bred by AI at first detection of oestrus (Day 0) and harvested at 22, 27, 32, 37, or 42 days of gestation. Each conceptus was counted and weighed to identify the large, medium, and small fetus in each litter. From these fetuses, HVP and LVP sections of tissue and necrotic tip (no placental attachment) were collected. Intact attached uterus and placenta were collected for histology and preserved in paraformaldehyde. Placentas were then stripped from the endometrium and individually weighed. Hematoxylin and eosin staining of uterine : placental sections was used to identify uterine fold development in the HVP, LVP, and uterine endometrial morphology in the necrotic tip regions. Three folds were measured for depth, width, and area using BQ Nova Prime software (Bioquant Image Analysis, Nashville, TN, USA). Data were analysed using PROC MIXED in SAS (SAS Institute Inc., Cary, NC, USA). Litter size, 12.1 ± 3.4, was similar (P = 0.86) for all days of gestation. Fetal and placental weight increased (P < 0.05) as day of gestation increased. Average fetal weight was similar (P = 0.30) for Day 27 and 32 with a tendency (P = 0.09) to increase by Day 37 before a significant increase at Day 42 (P = 0.002). The placenta increased (P = 0.02) in weight throughout this period of gestation, with the greatest increase in weight between 37 and 42 days of gestation. The LVP zones had no measureable fold formation until Day 32 from most conceptuses, and all LVP zones displayed microfold formation by Day 37. Necrotic tips became apparent after 27 days of gestation. Necrotic tip areas of the uterus had observable modifications from Day 32 to 42 of gestation, developing folds with dramatic changes in endometrial cell size and morphology. This work demonstrated fundamental time points in placental development that correspond to fetal growth and microfold formation. Gestation Day 27 through 32 show limited changes in either fetal growth or increased placental weight; however, significant morphological changes occur throughout the placenta, and even necrotic tips demonstrating the dynamic architecture of the establishing porcine placenta during early gestation.

Randomised clinical trial: the benefit of combination therapy with adefovir and lamivudine for chronic hepatitis B

BACKGROUND

Combination antiviral therapy holds the promise of increasing response rates while decreasing antiviral resistance, but has yet to be shown to be beneficial or necessary in chronic hepatitis B.

AIM

To evaluate the benefit of combination therapy with adefovir and lamivudine versus adefovir alone in maintaining virological, biochemical and histological responses.

METHODS

Patients with chronic hepatitis B with and without previous lamivudine therapy were randomised to receive adefovir alone (10 mg/daily) or adefovir and lamivudine (100 mg/daily) for up to 192 weeks. Study endpoints were (i) maintained virological (HBV DNA <500 copies/mL), biochemical and histological response, (ii) loss of HBeAg and (iii) loss of HBsAg.

RESULTS

A total of 41 patients were enrolled, including 31 HBeAg -positive and 31 treatment-naïve subjects. 30 patients remained on assigned therapy at 192 weeks. The percentage of patients achieving a combined maintained response was higher in the combination than the monotherapy arm, both at week 48 (59% vs. 26%, P = 0.06) and 192 (68% vs. 31%, P = 0.03). At week 192, 76% of the combination vs. 36% of the monotherapy group had loss of HBeAg (P = 0.03). One patient receiving adefovir cleared HBsAg. Adefovir resistance developed in 6 of 19 (32%) monotherapy but none of 22 combination treated patients (P = 0.03).

CONCLUSIONS

Extended combination therapy with lamivudine and adefovir is associated with a high rate of long-term virological and biochemical response. Adefovir monotherapy appears to be less effective mainly because of poor initial response and the ultimate development of antiviral resistance (www.Clinical. Trials.gov NCT00023309).

The sequential organ failure assessment (SOFA) score is prognostically superior to the model for end-stage liver disease (MELD) and MELD variants following paracetamol (acetaminophen) overdose

BACKGROUND

The prognostic value of the model for end-stage liver disease (MELD) and sodium-based MELD variants in predicting survival following paracetamol overdose remains unclear.

AIM

To examine the prognostic accuracy of sodium-based MELD variants in paracetamol-induced acute liver injury compared with the sequential organ failure assessment (SOFA) score.

METHODS

Retrospective analysis of 138 single time point paracetamol overdoses admitted to a tertiary liver centre. Individual laboratory samples were correlated with the corresponding clinical parameters in relation to time post-overdose, and the daily MELD, MELD-Na, MELDNa, MESO, iMELD, UKELD, updated MELD and SOFA scores were calculated.

RESULTS

Sixty-six (47.8%) patients developed hepatic encephalopathy, of whom 7 were transplanted and 21 died without liver transplantation. SOFA had a significantly greater area under the receiver operator characteristic for the prediction of spontaneous survival compared with MELD at both 72 (P = 0.024) and 96 (P = 0.017) h post-overdose. None of the sodium-based MELD variants improved the prognostic accuracy of MELD. A SOFA score >6 by 72 h or >7 by 96 h, post-overdose predicted death/transplantation with a negative predictive value of 96.9 (95% CI 90.2-99.4) and 98.8 (95% CI 93.6-99.9) respectively. SOFA and MELD had similar accuracy for predicting the development of hepatic encephalopathy (P = 0.493).

CONCLUSIONS

The SOFA score is superior to MELD in predicting spontaneous survival following paracetamol-induced acute liver injury. Modification of the MELD score to include serum sodium does not improve prognostic accuracy in this setting. SOFA may have potential as a quantitative triage marker following paracetamol overdose.

Silymarin use and liver disease progression in the Hepatitis C Antiviral Long-Term Treatment against Cirrhosis trial

BACKGROUND

Silymarin is the most commonly used herbal product for chronic liver disease; yet, whether silymarin protects against liver disease progression remains unclear.

AIM

To assess the effects of silymarin use on subsequent liver disease progression in 1049 patients of the Hepatitis C Antiviral Long-Term Treatment against Cirrhosis (HALT-C) trial who had advanced fibrosis or cirrhosis and had failed prior peginterferon plus ribavirin treatment.

METHODS

Patients recorded their use of silymarin at baseline and were followed up for liver disease progression (two point increase in Ishak fibrosis score across baseline, year 1.5, and year 3.5 biopsies) and over 8.65 years for clinical outcomes.

RESULTS

At baseline, 34% of patients had used silymarin, half of whom were current users. Use of silymarin was associated (P < 0.05) with male gender; oesophageal varices; higher ALT and albumin; and lower AST/ALT ratio, among other features. Baseline users had less hepatic collagen content on study biopsies and had less histological progression (HR: 0.57, 95% CI: 0.33-1.00; P-trend for longer duration of use=0.026). No effect was seen for clinical outcomes.

CONCLUSIONS

Silymarin use among patients with advanced hepatitis C-related liver disease is associated with reduced progression from fibrosis to cirrhosis, but has no impact on clinical outcomes (Clinicaltrials.gov #NCT00006164).

Plasma CRP levels in premenopausal women with major depression: a 12-month controlled study

C-reactive protein (CRP), an inflammatory marker of cardiovascular risk, is often elevated in major depressive disorder (MDD). The magnitude and consistency of this elevation have not been previously characterized in premenopausal women with MDD. The aim of the study was to prospectively assess plasma CRP levels, body composition, endocrine and metabolic parameters, and depressive status in premenopausal women with MDD (n=77) and controls (n=41), aged 21 to 45. Women were enrolled in a 12-month, controlled study of bone turnover, the P.O.W.E.R. ( Premenopausal, Osteoporosis, Women, Al Endronate, Dep Ression) Study. Blood samples were taken at Baseline, Month 6, and Month 12. Most subjects with MDD were in clinical remission. These women tended to have consistently higher CRP levels than controls over 12 months (p=0.077). BMI was positively related to log[CRP] in women with MDD only. Nine women with MDD had CRP levels greater than 10 mg/l, a value associated with a very high cardiovascular risk. This subset was obese and had significantly higher triglycerides, total cholesterol, LDL-cholesterol, fasting insulin, and HOMA-IR than the rest of women with MDD. The variations in CRP levels over time were high (intra- and inter-individual coefficients of variations of approximately 30-50% and approximately 70-140%, respectively). No control had CRP levels greater than 10 mg/l. Depression was associated with increased plasma CRP in women with MDD. The clinical significance of abnormal plasma CRP for cardiovascular risk needs to be assessed in large prospective studies of women with depression.

Utility of adiponectin as a biomarker predictive of glycemic efficacy is demonstrated by collaborative pooling of data from clinical trials conducted by multiple sponsors

This study, conducted under the Metabolic Disorders Steering Committee of the Biomarkers Consortium (a public-private partnership managed by the Foundation for the National Institutes of Health (FNIH)), analyzed blinded data on 2,688 type 2 diabetes (T2D) patients from randomized clinical trials conducted by four pharmaceutical companies. An increase in the levels of adiponectin was observed after peroxisome proliferator-activated receptor (PPAR)-agonist treatment (P < 0.0001), but not after treatment with non-PPAR drugs. This increase correlated with decreases in levels of glucose, hemoglobin A(1c) (Hb(A1c)), hematocrit, and triglycerides, and increases in levels of blood urea nitrogen, creatinine, and high-density lipoprotein cholesterol (HDL-C). Early (6-8 weeks) increases in levels of adiponectin after treatment with PPAR agonists showed a negative correlation (r = -0.21, P < 0.0001) with subsequent changes in levels of Hb(A1c). Changes in adiponectin level did not appear to be associated with baseline level of Hb(A1c). Logistic regression demonstrated that an increase in the level of adiponectin predicts a decrease in the level of Hb(A1c). These analyses confirm previously demonstrated relationships between adiponectin levels and metabolic parameters and support the robust predictive utility of adiponectin across the spectrum of glucose tolerance. Cross-company precompetitive collaboration is a feasible and powerful approach to biomarker qualification.

The spectrum of hepatic functional impairment in compensated chronic hepatitis C: results from the Hepatitis C Anti-viral Long-term Treatment against Cirrhosis Trial

BACKGROUND

The spectrum of functional impairment in patients with compensated chronic hepatitis C is incompletely defined.

AIM

To define hepatic impairment by quantitative tests (quantitative liver function tests) and correlate results with disease severity in patients with chronic hepatitis C.

METHODS

We studied 285 adult patients with chronic hepatitis C prior to treatment in the Hepatitis C Anti-viral Long-term Treatment against Cirrhosis Trial; 171 had Ishak fibrosis stages 2-4 (fibrosis) and 114 had stage 5 or 6 (cirrhosis). None had had clinical decompensation. A battery of 12 quantitative liver function test assessed the spectrum of hepatic microsomal, mitochondrial and cytosolic functions, and hepatic and portal blood flow.

RESULTS

Twenty-six to 63% of patients with fibrosis and 45-89% with cirrhosis had hepatic impairment by quantitative liver function test; patients with cirrhosis had the greatest impairment (P-value ranging from 0.15 to <0.0001). Cholate Cl(oral), cholate shunt and perfused hepatic mass correlated with cirrhosis, stage of fibrosis (r = -0.51, +0.49, -0.51), varices and variceal size (r = -0.39, +0.36, -0.41). PHM < 95 and cholate shunt >35% identified 91% of patients with medium- or large-sized varices.

CONCLUSIONS

Hepatic impairment is common in compensated patients with fibrosis or cirrhosis because of chronic hepatitis C. Cholate shunt, and cholate Cl(oral) and perfused hepatic mass, identify patients at risk for cirrhosis or varices.

Monocyte infiltration and kidney allograft dysfunction during acute rejection

Multiple cell types infiltrate acutely rejecting renal allografts. Typically, monocytes and T cells predominate. Although T cells are known to be required for acute rejection, the degree to which monocytes influence this process remains incompletely defined. Specifically, it has not been established to what degree monocytes impact the clinical phenotype of rejection or how their influence compares to that of T cells. We therefore investigated the relative impact of T cells and monocytes by correlating their presence as measured by immunohistochemical staining with the magnitude of the acute change in renal function at the time of biopsy in 78 consecutive patients with histological acute rejection. We found that functional impairment was strongly associated with the degree of overall cellular infiltration as scored using Banff criteria. However, when cell types were considered, monocyte infiltration was quantitatively associated with renal dysfunction while T-cell infiltration was not. Similarly, renal tubular stress, as indicated by HLA-DR expression, increased with monocyte but not T-cell infiltration. These data suggest that acute allograft dysfunction is most closely related to monocyte infiltration and that isolated T-cell infiltration has less acute functional impact. This relationship may be useful in assigning acute clinical relevance to biopsy findings.

Are peak flow and symptom measures good predictors of asthma hospitalizations and unscheduled visits?

Epidemiologic studies of pediatric respiratory health often include objective measures such as peak expiratory flow (PEF), and subjective measures such as symptom reports. These measures, however, are poorly correlated with each other, and there is little evidence that PEF is useful in predicting important health outcomes. Within a cohort of 791 inner-city children with asthma, we examined correlations between a series of five peak flow measures and five symptom scores obtained from 2-week diaries. The strongest correlations were found between "total peak flow lability" defined as: [(diary maximum - diary minimum)/diary mean] and "% of days with chest tightness" (r = 0.31). Logistic models evaluated peak flow and symptoms as predictors of an important health outcome: hospitalization or emergency department or unscheduled clinic visit for asthma within 30 days of starting the diary. Each of the peak flow and symptom measures was significantly related to utilization. However, the predictive power of each measure was low (range of area under ROC curve, 0.54-0.67). Models including only peak flow or symptoms had greater prediction than models with risk factors such as atopy, asthma persistence, and age. The prediction from a model with the risk factors and symptoms was not improved by adding a peak flow measure to the model (increase in area under ROC, 0.67-0.68). Stratified analyses suggest that prediction was similar in the fall vs. winter, spring, and summer months. Greater prediction of health outcomes was found among more persistent asthmatics and children who were nonatopic. These findings suggest that in a research setting, peak flow monitoring in children did not add prediction beyond that obtained from symptom reports. Pediatr Pulmonol. 2001; 31:190-197. Published 2001 Wiley-Liss, Inc.

Long-term mortality and morbidity of transfusion-associated non-A, non-B, and type C hepatitis: A National Heart, Lung, and Blood Institute collaborative study

Persons with non-A, non-B hepatitis (cases) identified in 5 transfusion studies in the early 1970s have been followed ever since and compared for outcome with matched, transfused, non-hepatitis controls from the same studies. Previously, we reported no difference in all-cause mortality but slightly increased liver-related mortality between these cohorts after 18 years follow-up. We now present mortality and morbidity data after approximately 25 years of follow-up, restricted to the 3 studies with archived original sera. All-cause mortality was 67% among 222 hepatitis C-related cases and 65% among 377 controls (P = NS). Liver-related mortality was 4.1% and 1.3%, respectively (P =.05). Of 129 living persons with previously diagnosed transfusion-associated hepatitis (TAH), 90 (70%) had proven TAH-C, and 39 (30%), non-A-G hepatitis. Follow-up of the 90 TAH-C cases revealed viremia with chronic hepatitis in 38%, viremia without chronic hepatitis in 39%, anti-HCV without viremia in 17%, and no residual HCV markers in 7%. Thirty-five percent of 20 TAH-C patients biopsied for biochemically defined chronic hepatitis displayed cirrhosis, representing 17% of all those originally HCV-infected. Clinically evident liver disease was observed in 86% with cirrhosis but in only 23% with chronic hepatitis alone. Thirty percent of non-A, non-B hepatitis cases were unrelated to hepatitis viruses A,B,C, and G, suggesting another unidentified agent. In conclusion, all-cause mortality approximately 25 years after acute TAH-C is high but is no different between cases and controls. Liver-related mortality attributable to chronic hepatitis C, though low (<3%), is significantly higher among the cases. Among living patients originally HCV-infected, 23% have spontaneously lost HCV RNA.

The relationship of acute transfusion-associated hepatitis to the development of cirrhosis in the presence of alcohol abuse

BACKGROUND

Although concomitant alcoholism is widely believed to enhance liver disease progression in persons with hepatitis C virus (HCV) infection, this relationship has not been well quantified.

OBJECTIVE

To quantify the relationship of transfusion-associated HCV infection and history of heavy alcohol abuse to development of cirrhosis.

DESIGN

Retrospective cohort study.

SETTING

Liver clinics in university and government hospitals.

PATIENTS

Extended follow-up of 1030 patients in prospective investigations of transfusion-associated viral hepatitis conducted in the United States between 1968 and 1980.

MEASUREMENTS

Development of cirrhosis and history of heavy alcohol abuse were determined from review of interviews with patients or their proxies, medical records, death certificates, and autopsy and biopsy reports. Logistic regression was used to estimate the risk for cirrhosis associated with transfusion-associated HCV infection and history of heavy alcohol abuse.

RESULTS

The absolute risk for cirrhosis was 17% among patients with transfusion-associated HCV; 3.2% among patients with transfusion-associated non-A, non-B, non-C hepatitis; and 2.8% among controls. Patients with transfusion-associated HCV were more likely than controls to develop cirrhosis (odds ratio, 7.8 [95% CI, 4.0 to 15.1]). A history of heavy alcohol abuse was associated with a fourfold increased risk for cirrhosis. Hepatitis C virus infection plus a history of heavy alcohol abuse led to a substantial increase in risk for cirrhosis (odds ratio, 31.1 [CI, 11.4 to 84.5]) compared with controls without such a history.

CONCLUSIONS

Heavy alcohol abuse greatly exacerbates the risk for cirrhosis among patients with HCV infection. This finding emphasizes the need to counsel such patients about their drinking habits.

Mouse allergen. I. The prevalence of mouse allergen in inner-city homes. The National Cooperative Inner-City Asthma Study

BACKGROUND

Although mouse allergen is a well-defined cause of IgE-mediated hypersensitivity in occupational settings, it has not been well studied in the general population.

OBJECTIVE

We sought to determine the prevalence of mouse allergen in inner-city homes.

METHODS

A subset of 608 homes from the National Cooperative Inner-City Asthma Study population had dust samples adequate for analysis of mouse allergen. In addition, data regarding the demographics and housing of the subjects were related to the mouse allergen levels.

RESULTS

Ninety-five percent of all homes had detectable mouse allergen (Mus m 1) in at least one room, with the highest levels found in kitchens (kitchen: range, 0-618 microg/g; median, 1.60 microg/g; bedroom: range, 0-294 microg/g; median, 0.52 microg/g; television-living room: range, 0-203 microg/g; median, 0. 57 microg/g). By city, 100% of the kitchens in Baltimore had detectable mouse allergen, with the lowest percentage (74%) in Cleveland. Mouse allergen levels correlated among rooms (R = 0.65-0. 75). Forty-nine percent of the homes had reported problems with mice within the last year, and 29% of the homes had evidence of mice in one or more rooms on home inspection and had higher levels of mouse allergen (P =.0001). Higher allergen levels were also associated with evidence of cockroach infestation in any room (P =.006). None of the other subject or housing demographics evaluated were associated with a higher prevalence or level of mouse allergen.

CONCLUSIONS

We conclude that mouse allergen is widely distributed in inner-city homes and that cockroach infestation is associated with high mouse allergen levels.

Mouse allergen. II. The relationship of mouse allergen exposure to mouse sensitization and asthma morbidity in inner-city children with asthma

BACKGROUND

Although mouse allergen is known to cause occupational asthma in laboratory workers, its potential significance in home environments has never been studied.

OBJECTIVE

This study was designed to define the prevalence of mouse sensitivity and its relationship to mouse allergen exposure and disease activity in inner-city children with asthma.

METHODS

A subset of 499 subjects from the National Cooperative Inner-City Asthma Study had dust samples adequate for mouse allergen analysis, as well as valid puncture skin test (PST) results. Data were analyzed to relate mouse allergen exposure and other risk factors to mouse sensitization and asthma morbidity.

RESULTS

Eighty-nine (18%) of the 499 children had a positive mouse skin test response. Children whose homes had mouse allergen levels above the median (1.60 microg/g) in the kitchen had a significantly higher rate of mouse sensitization (23% vs 11%, P =. 007). Atopy was also significantly related to mouse sensitization, with 40% of those with more than 4 positive PST responses having mouse sensitivity compared with 4% of those with no other positive PST responses (P <.0001). When atopy and exposure were considered together, 53% of those with more than 4 positive PST responses and allergen levels above the median had a positive PST response to mouse allergen compared with 22% of those with more than 4 positive PST responses and allergen levels below the median (P <.0001). The relationship among mouse allergen exposure, sensitization, and any measures of asthma morbidity was not statistically significant.

CONCLUSIONS

Mouse allergen may be an important indoor allergen in inner-city children with asthma, with exposure and atopy contributing to mouse sensitization.

Factors that influence adolescent adaptation to sickle cell disease

OBJECTIVE

To examine whether psychosocial factors play a more important role than biomedical risk factors in predicting adolescent adaptation to sickle cell disease (SCD); to determine whether psychosocial factors moderate the relationship between biomedical risk factors and adaptation.

METHODS

Ninety African American adolescents from the multisite Cooperative Study of Sickle Cell Disease were recruited to complete a battery that included measures of psychosocial status and psychological adaptation. Data regarding their health status were collected from medical records.

RESULTS

The findings revealed that intrapersonal (self-esteem, social assertiveness), stress-processing (use of social support), and social ecological factors (family relations) were significant predictors of adaptation; however, biomedical factors did not predict adaptation. There was no evidence that psychosocial factors moderated the relationship between biomedical risk factors and adaptation.

CONCLUSIONS

Psychosocial factors proved to be better predictors of adaptation than biomedical risk factors. Additional research is needed to better understand the nature of the interrelationships among biomedical risk factors, psychosocial factors, and adaptation.

Multicenter comparison of magnetic resonance imaging and transcranial Doppler ultrasonography in the evaluation of the central nervous system in children with sickle cell disease

PURPOSE

To compare the results of standardized magnetic resonance imaging (MRI) of the brain and transcranial Doppler (TCD) ultrasonography of cerebral arteries in school-aged children with sickle cell disease to determine the correlation between these two different neurodiagnostic tests.

PATIENTS AND METHODS

Data were analyzed from 78 children with sickle cell disease (mean age 11 yrs) who participated in both the Cooperative Study of Sickle Cell Disease (CSSCD) and the Stroke Prevention Trial in Sickle Cell Anemia (STOP). Patients who had experienced an overt stroke were excluded. MRI findings were classified as normal or "silent infarct." Results of TCD were classified as normal, conditional, or abnormal, based on the time-averaged maximum mean flow velocity in the proximal middle cerebral and distal internal carotid arteries.

RESULTS

Of 61 patients who had a normal MRI examination, 11 (18%) had either conditional (5 patients) or abnormal (6 patients) TCD results. Among 17 patients in whom silent infarction was seen on MRI, only 5 (29%) had a conditional (1 patient) or abnormal (4 patients) TCD velocity. Thus, discordant results were seen in 23 patients: 12 in which the TCD result was normal and the MRI abnormal; 11 in which the TCD velocity was elevated and the MRI normal.

CONCLUSIONS

Abnormal TCD and MRI examinations reveal different aspects of the pathophysiology of central nervous system (CNS) injury in sickle cell disease and are often discordant. Although TCD abnormality is predictive of overt stroke, the lack of concordance between TCD and MRI findings suggests a need to develop more sensitive and specific indicators of early CNS pathology, such as neuropsychometric testing and positron-emission tomography (PET) scans, and to obtain more information about microvascular pathologic processes that may affect CNS function.

Fenfluramine challenge in unipolar depression with and without anger attacks

We have previously hypothesized that patients with major depression and anger attacks may have a greater central serotonergic dysregulation than depressed patients without such attacks. We wanted to compare the prolactin response to fenfluramine challenge, as an indirect measure of central serotonergic function, in depressed patients with and without anger attacks. We recruited 37 outpatients (22 men and 15 women; mean age: 39.5+/-10.5) with DSM-III-R major depressive disorder, diagnosed with the SCID-P. Their initial 17-item Hamilton Rating Scale for Depression score was >/=16. Patients were classified as either having or not having anger attacks with the Anger Attacks Questionnaire. All patients received a single-blind placebo challenge followed by a fenfluramine challenge (60 mg orally) the next day. Plasma prolactin measurements were obtained with double antibody radioimmunoassay before and after both placebo and fenfluramine challenges, and fenfluramine and norfenfluramine blood levels after each challenge were determined by gas chromatography. Of the 37 study participants, 17 (46%) were classified as having anger attacks. There were no significant differences in age, gender, fenfluramine, or norfenfluramine blood levels between depressed patients with and without anger attacks. Depressed patients with anger attacks showed a significantly blunted prolactin response to fenfluramine challenge compared to patients without anger attacks. As previous studies have shown blunted prolactin responses to fenfluramine in impulsive aggression among patients with personality disorders, our results support our hypothesis that depressed patients with anger attacks may have a relatively greater serotonergic dysregulation than depressed patients without these attacks.

Anxiety disorders in major depression

The prevalence and clinical impact of anxiety disorder comorbidity in major depression were studied in 255 depressed adult outpatients consecutively enrolled in our Depression Research Program. Comorbid anxiety disorder diagnoses were present in 50.6% of these patients and included social phobia (27.0%), simple phobia (16.9%), panic disorder (14.5%), generalized anxiety disorder ([GAD] 10.6%), obsessive-compulsive disorder ([OCD] 6.3%), and agoraphobia (5.5%). While both social phobia and generalized anxiety preceded the first episode of major depression in 65% and 63% of cases, respectively, panic disorder (21.6%) and agoraphobia (14.3%) were much less likely to precede the first episode of major depression than to emerge subsequently. Although comorbid groups were not distinguished by depression, anxiety, hostility, or somatic symptom scores at the time of study presentation, patients with comorbid anxiety disorders tended to be younger during the index episode and to have an earlier onset of the major depressive disorder (MDD) than patients with major depression alone. Our results support the distinction between anxiety symptoms secondary to depression and anxiety disorders comorbid with major depression, and provide further evidence for different temporal relationships with major depression among the several comorbid anxiety disorders.

Evolution of remission as the new standard in the treatment of depression

Epidemiologic and clinical data support the goal of treating depressed patients to wellness or full remission. Many patients improve but fail to achieve full remission with antidepressant treatment and continue to have residual symptoms, which cause distress and dysfunction. These residual symptoms may meet criteria for subsyndromal and minor depression. Patients who have these milder syndromes after treatment have a greater risk of relapse and recurrence than do those who remain symptom-free. Clinical trials of antidepressants have shown lower rates of remission than of responses that fall short of remission, although some dual-acting antidepressants (e.g., serotonin-norepinephrine reuptake inhibitors) may have higher remission rates than other agents. Treatment with such robust dual-acting antidepressants may result in higher rates of remission and fewer residual symptoms than treatment with selective serotonin reuptake inhibitors.

Results of the National Cooperative Inner-City Asthma Study (NCICAS) environmental intervention to reduce cockroach allergen exposure in inner-city homes

BACKGROUND

Cockroach allergen is important in asthma. Practical methods to reduce exposure are needed.

OBJECTIVE

We sought to evaluate the effectiveness of house cleaning and professional extermination on lowering cockroach antigen levels in inner-city dwellings.

METHODS

As part of the National Cooperative Inner-City Asthma Study intervention, 265 of 331 families with asthmatic children who had positive skin test responses to cockroach allergen consented to a professional home extermination with 2 applications of a cockroach insecticide (Abamectin, Avert) combined with directed education on cockroach allergen removal. On a random subset of 48 homes undergoing cockroach extermination in the intervention group, Bla g 1 was measured in settled dust from the kitchen, bedroom, and TV/living room. The first sample was collected 1 week before extermination, with additional samples after the exterminations at approximately 2, 6, and 12 months after the first sample. Self-reported problems with cockroaches were collected at baseline and after 12 months of follow-up in both the intervention and control group.

RESULTS

The geometric mean kitchen level of Bla g 1 decreased at 2 months (33.6 U/g) relative to preextermination levels (68.7 U/g, P <.05). The percent of kitchens with over 8 U/g of Bla g 1 followed a similar pattern, but only the decrease from preextermination to 6-month levels was significant (86.8% vs 64.3%, P <.05). By the 12-month visit, the allergen burden had returned to or exceeded baseline levels. Except for an increase in the bedroom at 2 months (8.9 U/g vs 11.1 U/g, P <.05), no other significant change was seen. Only about 50% of the families followed the cleaning instructions; no greater effect was found in these homes. Self-reported problems with cockroaches showed no difference between the intervention and control group after 1 year of follow-up.

CONCLUSIONS

Despite a significant, but short-lived, decrease the cockroach allergen burden remained well above levels previously found to be clinically significant.

Measurement of anticonvulsant adherence behaviour in the community using a Medication Events Monitoring System (MEMS)

The Medication Event Monitoring System (MEMS) is a relatively new device designed to overcome some of the disadvantages of traditional adherence-measuring techniques. MEMS has also been found useful in tracking adherence behaviour without the need to visit patients frequently. In this study each patient was given a pre-filled, labelled MEMS bottle and cap. Patients were monitored for 24 weeks. For patients specifically studied, there were periods when drug levels may have been low and some exhibited erratic medication-taking behaviour. It is concluded that MEMS can measure adherence behaviour objectively, and so might be used to improve prescribing decisions, identify drug wastage and improve carer support. Further research is needed before the routine use of electronic medication monitoring can be recommended.

Self-reported adherence, management behavior, and barriers to care after an emergency department visit by inner city children with asthma

OBJECTIVE

The inability to adhere to a prescribed therapeutic program for the treatment of a chronic disease may be responsible in part for continued disease activity. This problem may be more of an issue in the treatment of asthma, a common, potentially lethal chronic condition in which the lack of symptoms may be interpreted as remission. Adherence was one of the key areas of interest for the National Cooperative Inner-City Asthma Study. The focus of this study was to identify those issues reported by families that could adversely affect their adherence to an asthma care program. The identification of barriers to adherence could then form the basis of a successful intervention program. This study describes barriers to adherence, asthma management behavior, and self-reported adherence.

METHODS

Patients presenting during an acute attack of asthma at an emergency department (ED) were recruited for this study. The medical record of the ED encounter was abstracted and compared with information that was obtained during a baseline interview 3 to 5 weeks later. During the baseline interview, parents were asked about health care behaviors related to adherence.

RESULTS

There were 344 children 4 to 9 years of age living in inner city census tracts in the study. Four areas of adherence (medicine use, appointment-keeping, emergency actions, and asthma attack prevention) were investigated. The parental report of medications prescribed at the ED and the information on the abstracted ED report agreed 94.9% of the time for the beta-agonists, 86.8% for steroids, and 69.4% for cromolyn. Among respondents, 85.4% of parents reported that they are able to follow the ED recommendations almost all of the time; side effects of medicines were a concern for 81.1% of caretakers who were adherent and for 89.5% of caretakers who were nonadherent. Doubts regarding the usefulness of medications occurred in 34.4% of those considered adherent and 54.2% who admitted nonadherence. Medications were forgotten some of the time by 45.2% of the children, and 52.8% tried to get out of taking medicine. Appointments for follow-up care were kept by 69% of those given an appointment in the ED, by an estimated 60.0% of those who were told specifically to call for an appointment, and by an estimated 25.2% of those who were neither given an appointment nor told specifically to make one. Only one third of parents report that they were able to keep the child away from known asthma triggers nearly all of the time. Approximately half avoided allergens; however, only 37.5% reported avoidance of cigarette smoke. The use of preventive medicines occurred in 23.5%. Using a medicine and taking the child to a physician were reported as the first or second action during an acute attack of asthma by 72.1% of respondents.

CONCLUSIONS

Adherence to an asthma-management program involves a number of areas: medication, appointment-keeping, prevention, and applying an emergency plan of action. Barriers to adherence may exist in one or all four of these areas, leading to ineffective control of asthma. Recommendations are made for improving the patient-physician partnership to improve adherence.

Pharmacokinetics of dichloroacetate in adult patients with lactic acidosis

The pharmacokinetic properties of the lactate-lowering drug dichloroacetate were investigated in 111 adult patients with lactic acidosis who were randomized to receive dichloroacetate as part of a placebo-controlled clinical trial. The clinical symptoms and etiology of lactic acidosis varied markedly among patients. Dichloroacetate, at a dose of 50 mg per kilogram of body weight, was administered in a 30-minute intravenous infusion into a peripheral vein. A second dose, identical to the first, was administered 2 hours after beginning the first infusion. Plasma levels of dichloroacetate were determined from blood samples collected periodically up to 288 hours after administration and the data were subjected to pharmacokinetic modeling. The pharmacokinetic properties of dichloroacetate in these acutely ill patients were complex and differed markedly from those in healthy volunteers, whose data fitted a one-compartment pharmacokinetic model. In contrast, the data from patients fitted one-, two-, or three-compartment pharmacokinetic models or even none of these, depending on the individual. Drug clearance in plasma tended to decrease as the number of compartments required to fit the data increased or as the number of drug treatments increased.

Acute chest syndrome in sickle cell disease: clinical presentation and course. Cooperative Study of Sickle Cell Disease

Acute chest syndrome (ACS) is an important cause of morbidity and mortality in sickle cell disease (SCD). Previous studies reported conflicting pictures of ACS making therapeutic interventions difficult. The Cooperative Study of Sickle Cell Disease prospectively followed 3,751 patients enrolled from birth to 66 years of age for ACS. Data on presenting signs and symptoms, laboratory findings, and hospital course were collected. There were 1,722 ACS episodes in 939 patients. Young children (age 2 to 4 years) presented with fever and cough, a negative physical exam, and rarely had pain. Adults were often afebrile and complained of shortness of breath, chills, and severe pain. Upper lobe disease was more common in children; multilobe and lower lobe disease affected adults more often. Severe hypoxia occurred in 18% of adults tested and could not be predicted by examination or laboratory findings. Bacteremia was documented in 3.5% of episodes, but was strongly influenced by age (14% of infants and 1.8% of patients > 10 years). ACS was most common in winter with children having the most striking increase. Transfusion was used less frequently, but earlier in children. Young children were hospitalized for 5.4 days versus 9 days for adults. Fifty percent of adults had a pain event in the 2 weeks preceding ACS and children were more likely to have febrile events. The death rate was four times higher in adults than in children. Fatal cases generally developed rapid pulmonary failure and one third were associated with bacteremia. Age has a striking effect on the clinical picture of ACS. In children, ACS was milder and more likely due to infection, whereas in adults ACS was severe, associated with pain and had a higher mortality rate.

Natural history of blood pressure in sickle cell disease: risks for stroke and death associated with relative hypertension in sickle cell anemia

PURPOSE

Blood pressure in individuals who have sickle cell disease has been reported to be lower than published normal values. We determine whether and to what degree this is true, using data obtained as part of a large natural history study.

PATIENTS AND METHODS

Blood pressure was measured annually for 3,317 subjects with sickle cell disease who were 2 years old or older. Values obtained were compared with those reported by the National Health and Nutrition Examination Survey I and II (NHANES I and II). They were further analyzed with respect to age, sex, height, weight, hematologic diagnosis, blood urea nitrogen and creatinine, stroke, and death.

RESULTS

Blood pressure was significantly lower in subjects with sickle cell anemia than published norms for age, race, and sex, a difference that increased with age. It correlated with body mass index, hemoglobin, measures of renal function and age, but the strength of the correlation varied among age and sex subgroups. The risk for occlusive stroke increased with systolic but not diastolic pressure. Mortality was related to elevated blood pressure in males (P < 0.05) and to a lesser extent in females (P = 0.10). In subjects with hemoglobin SC disease, blood pressure also deviated from normal but to a lesser degree.

CONCLUSION

Blood pressure is generally lower than normal in individuals with sickle cell anemia. Those with high values relative to this population had an increased risk of stroke and death. Blood pressure should be monitored but values obtained must be assessed relative to the lower values expected for patients with this disease. Those with blood pressure values above 140/90 mm Hg should be evaluated and considered for treatment.

Short-term compliance with peak flow monitoring: results from a study of inner city children with asthma

The objective of the study was to assess the feasibility of initiating daily peak flow monitoring in a research study of asthma in inner city children. We performed a descriptive study of patterns of peak flow monitoring in children randomized to receive a simple mini-Wright (SM) or an electronic recording meter (ERM). The ERM served as a "covert" meter, providing objective documentation of actual peak flow use. Sixty-five Hispanic or African-American children, ages 5-9 years, with a history of physician-diagnosed asthma participated in the study. All children resided in census tracts with 40% or more of the population living at or below the poverty level. Subjects were instructed to use a peak flow meter (the SM or ERM) at least twice daily over a 3 week period, and to record peak flow values in a paper diary. Subjects who received the ERM were not made aware that measurements were also recorded electronically. Differences in patterns of use of the SM and ERM were assessed with the Wilcoxon signed rank test and Wilcoxon sum rank test. Adherence to peak flow monitoring was evaluated by comparing the percent days with missing values in the manually completed diary with those obtained by computer record. The Friedman statistic was used to compare changes in compliance (percent of days with missing peak flow entries) over time. Accuracy of peak flow readings was assessed by comparing the manual and electronic recordings with paired and unpaired t-tests and with Pearson product moment correlations. The percent of days with missing peak flow entries on diaries increased from 1.4% to 10.6% from the first to third week of monitoring (P < 0.004). The ERMs indicated a significantly greater percent of missing data than did the manual records (P < 0.0002). The difference in the percent of missing data for the electronic and manual records was most notable during the third study week, when the ERM and the manually completed records indicated that 52% and 15% of days, respectively, were without peak flow measures. Large inter-subject variations in the relationship between manually and electronically recorded peak flow measurements were observed, suggesting that errors in reading and transcribing peak flow rates occur in a subset of asthmatics. We conclude that children and caretakers in the inner city may have considerable difficulty initiating and maintaining peak flow recordings. Data obtained by manual records may considerably overestimate actual use. Compliance with monitoring decreases markedly between the first and third week of monitoring.

Natural history and course of acquired lactic acidosis in adults. DCA-Lactic Acidosis Study Group

STUDY OBJECTIVE

To determine the pathogenesis and clinical course of lactic acidosis in adults receiving standard medical care.

DESIGN

Placebo arm of a 5-year prospective, randomized, blinded study comparing placebo and dichloroacetate as specific lactate-lowering therapy. Each patient received intravenous saline placebo in addition to conventional therapy.

SETTING

Intensive care units of 10 tertiary care hospitals in North America.

PATIENTS

One hundred twenty-six patients with lactic acidosis, defined as arterial blood lactate greater than or equal to 5 mmol/L and either arterial pH of less than or equal to 7.35 or base deficit greater than 6 mmol/L. Patients were followed for up to 6 months.

MEASUREMENTS AND MAIN RESULTS

Mean +/- SD demographic entry data for 126 patients included: age 56 +/- 17 years, lactate 10.4 +/- 5.5 mmol/L, pH 7.24 +/- 0.14, calculated base deficit 14.1 +/- 5.4, arterial systolic blood pressure 103 +/- 29 mm Hg, Glasgow Coma score 7.9 +/- 4.9, and APACHE II score 19.2 +/- 8.1. Despite fluids and pressors, 32% of patients had systolic blood pressures of less than or equal to 90 mm Hg in association with sepsis (59%), cardiac failure (18%), or hemorrhage (18%). The most common causes of lactic acidosis in the absence of shock were sepsis (49%), liver disease (15%), and respiratory failure (12%). The median survival was 38.5 hours. Survival at 24 hours was 59%. Arterial pH predicted 24-hour survival better than base deficit or bicarbonate level. Percent survival was 41% at 3 days and 17% at 30 days. Only 21% of patients survived to leave the intensive care unit, and 17% were discharged from the hospital. In patients receiving sodium bicarbonate, neither acid-base nor hemodynamic status improved.

CONCLUSIONS

In this first prospective study of the clinical course of acute lactic acidosis in adults, nearly all subjects had both hemodynamic and nonhemodynamic (metabolic) underlying causes, many of which independently predicted survival and most of which were refractory to standard care.

Vigabatrin in adults with poorly-controlled epilepsy and learning disabilities

Twenty-two adult patients with uncontrolled epilepsy and severe learning difficulties were included in an open study of vigabatrin. Patients were all in residential care and had experienced at least 12 seizures during the previous 12 months despite all attempts to optimize antiepileptic drug (AED) treatment. Following a 4 month baseline period, vigabatrin 500 mg twice daily was added to the current AED treatment and the dose increased according to response, up to a maximum of 4 g/day. Ten patients achieved a reduction in seizure frequency of more than 50% during this 4 month dose titration phase. Two patients had no seizures during the baseline period. For the 30 patients with seizures during the baseline period the median improvement in seizure frequency with the addition of vigabatrin was 49% (P = 0.014). The response rate was higher for patients with partial seizures than for those with generalized seizures. Ten patients continued with vigabatrin while the dose of one of their other AEDs was gradually reduced and successfully withdrawn in three patients. Adverse events were reported in 20 patients during the 64 week study period. The most frequently reported events were sedation (8 patients), aggression (4 patients), agitation (3 patients) and ataxia (3 patients). No patients were withdrawn from the study as a consequence of adverse events. Vigabatrin was therefore an effective add-on therapy in 45% of these difficult-to-treat patients and allowed reduction of other AED treatment in a small number.

A controlled trial of intravenous immune globulin to reduce nosocomial infections in very-low-birth-weight infants. National Institute of Child Health and Human Development Neonatal Research Network

BACKGROUND

Nosocomial infections are a major cause of morbidity and mortality in premature infants. As a rule, their low serum gamma globulin levels at birth subsequently decline to hypogammaglobulinemic values; hence, prophylactic administration of intravenous immune globulin may reduce the rate of hospital-acquired infections.

METHODS

In this prospective, multicenter, two-phase controlled trial, 2416 infants were stratified according to birth weight (501 to 1000 g and 1001 to 1500 g) and randomly assigned to an intravenous immune globulin group (n = 1204) or a control group (n = 1212). Control infants were given placebo infusions during phase 1 of the study (n = 623) but were not given any infusions during phase 2 (n = 589). Infants weighing 501 to 1000 g at birth were given 900 mg of immune globulin per kilogram of body weight, and infants weighing 1001 to 1500 g at birth were given a dose of 700 mg per kilogram. The immune globulin infusions were repeated every 14 days until the infants weighed 1800 g, were transferred to another center, died, or were sent home from the hospital.

RESULTS

Nosocomial infections of the blood, meninges, or urinary tract occurred in 439 of the 2416 infants (18.2 percent): 208 (17.3 percent) in the immune globulin group and 231 (19.1 percent) in the control group (relative risk, 0.91; 95 percent confidence interval, 0.77 to 1.08). Septicemia occurred in 15.5 percent of the immune globulin recipients and 17.2 percent of the controls. During phase 1 the rate of nosocomial infections was 13.4 percent in the immune globulin group and 17.8 percent in the control group; the respective rates during phase 2 were 21.0 percent and 20.4 percent. The predominant organisms included gram-positive cocci (53.0 percent), gram-negative bacilli (22.4 percent), and candida species (16.0 percent). Adverse reactions were rarely observed during the infusions. Immune globulin therapy had no effect on respiratory distress syndrome, bronchopulmonary dysplasia, intracranial hemorrhage, the duration of hospitalization, or mortality. The incidence of necrotizing enterocolitis was 12.0 percent in the immune globulin group and 9.5 percent in the control group.

CONCLUSIONS

Prophylactic use of intravenous immune globulin failed to reduce the incidence of hospital-acquired infections in very-low-birth-weight infants.

A multicenter randomized trial comparing two surfactants for the treatment of neonatal respiratory distress syndrome. National Institute of Child Health and Human Development Neonatal Research Network

OBJECTIVE

To compare the efficacy of two surfactants, Exosurf Neonatal (Burroughs Wellcome Co.) and Survanta (Ross Laboratories), for the treatment of neonatal respiratory distress syndrome.

DESIGN

Multicenter randomized trial.

SETTING

Eleven tertiary care university neonatal intensive care units participating in the National Institute of Child Health and Human Development Neonatal Research Network.

PATIENTS

Newborn infants (n = 617) weighing 501 to 1500 gm with respiratory distress syndrome who were receiving assisted ventilation with 30% oxygen or more within 6 hours of birth were enrolled between January 1991 and January 1992.

INTERVENTIONS

Infants were randomly assigned to receive up to four intratracheal doses of either Exosurf Neonatal (n = 309) or Survanta (n = 308).

MAIN OUTCOME MEASURES

The occurrence of death or bronchopulmonary dysplasia 28 days after birth and the average fraction of inspired oxygen (FIO2) and mean airway pressure (MAP) during the first 72 hours after treatment.

RESULTS

Death or bronchopulmonary dysplasia occurred in 67% of the infants in the Exosurf group and 62% of those in the Survanta group (adjusted relative risk, 1.07; 95% confidence interval, 0.96 to 1.20). During the 72 hours after the first surfactant dose, the average FIO2 (+/- SEM) was 0.50 +/- 0.01 for Exosurf and 0.42 +/- 0.01 for Survanta (difference, 0.08; 95% confidence interval, 0.05 to 0.11); the average MAP (+/- SEM) was 7.64 +/- 0.21 cm H2O for Exosurf and 6.93 +/- 0.21 cm H2O for Survanta (difference, 0.71 cm H2O; 95% confidence interval, 0.13 to 1.29 cm H2O). There was no difference between the groups in the incidence of other neonatal morbidities or in the duration of hospitalization, assisted ventilation, or supplemental oxygen administration.

CONCLUSION

We found no difference between treatment groups in the incidence of death or bronchopulmonary dysplasia, although we did observe a difference in the initial response to treatment as measured by FIO2 and MAP.

Non-compliance--or how many aunts has Matilda?

The compliance of patients with medication prescribed for them is a challenge. It seems that one-third of patients comply adequately, one-third more-or-less, and one-third are non-compliant, so that compliance rates hover around 50%. This can be improved upon, but not by treating failure to comply as a deplorably aberrant behaviour. First we need to know more about compliance and non-compliance, and that means standardising methods of study and measuring, by questioning the patient, counting tablets, or looking at drug metabolites or markers in faeces, blood or urine. Doctors' prejudices and patients' perceptions alike have to be taken into account since strategies for improvement must include both educating the prescriber and counselling the patient.

Decreasing mortality associated with the introduction of surfactant therapy: an observational study of neonates weighing 601 to 1300 grams at birth. The Members of the National Institute of Child Health and Human Development Neonatal Research Network

OBJECTIVE

To determine whether the introduction of surfactant therapy was associated with decreased mortality for high-risk preterm neonates weighing 601 to 1300 g at birth.

DESIGN

Before-after observational study.

SETTING

Eight tertiary care neonatal intensive care units participating in the National Institute of Child Health and Human Development Neonatal Research Network.

PATIENTS

The outcomes for neonates with birth weight 601 to 1300 g admitted in the 2 years before surfactants became available (n = 2780) were compared with those of neonates admitted in the year beginning 2 months after surfactants became available (n = 1413).

MAIN OUTCOME MEASURES

The primary outcome measure was in-hospital mortality; secondary outcome measures included durations of assisted ventilation, length of hospitalization, and neonatal morbidity.

RESULTS

Forty percent of neonates in the postsurfactant group received surfactant (range 28% to 69% at the centers). Mortality decreased from 27.8% before to 19.9% after surfactant therapy was introduced (Mantel-Haenszel chi 2 = 31.4, P = .001). The adjusted odds ratio for mortality after surfactants became available was 0.73 (95% confidence interval 0.55 to 0.95). The duration of assisted ventilation and length of hospitalization increased after surfactants were introduced (P = .0001 for both outcomes).

CONCLUSION

Mortality for neonates weighing 601 to 1300 g decreased after surfactant therapy was introduced, suggesting that the efficacy of surfactants demonstrated in randomized controlled trials will translate into effectiveness in routine clinical care.

Long-term mortality after transfusion-associated non-A, non-B hepatitis. The National Heart, Lung, and Blood Institute Study Group

BACKGROUND

Acute non-A, non-B hepatitis after blood transfusion often progresses to chronic hepatitis and sometimes culminates in cirrhosis or even hepatocellular carcinoma. However, the frequency of these sequelae and their effects on mortality are not known.

METHODS

We traced patients with transfusion-related non-A, non-B hepatitis who had been identified in five major prospective studies conducted in the United States between 1967 and 1980. We matched each patient with two control subjects (identified as the first and second controls) who received transfusions but who did not have hepatitis. The mortality rates in the three groups were determined with use of data from the National Death Index and Social Security Death Tapes. Cause-specific mortality was determined by reviewing death certificates.

RESULTS

Vital status was established for over 94 percent of the 568 patients who had had non-A, non-B hepatitis and the two control groups (526 first controls and 458 second controls). After an average follow-up of 18 years, the estimate by life-table analysis of mortality from all causes was 51 percent for those with transfusion-associated non-A, non-B hepatitis, as compared with 52 percent for the first controls and 50 percent for the second controls. The survival curves for the three groups were virtually the same. Mortality related to liver disease was 3.3, 1.1, and 2.0 percent, respectively, among the three groups (P = 0.033 for the comparison of the group with non-A, non-B hepatitis with the combined control group). Seventy-one percent of the deaths related to liver disease occurred among patients with chronic alcoholism.

CONCLUSIONS

In this long-term follow-up study, there was no increase in mortality from all causes after transfusion-associated non-A, non-B hepatitis, although there was a small but statistically significant increase in the number of deaths related to liver disease.

A controlled clinical trial of dichloroacetate for treatment of lactic acidosis in adults. The Dichloroacetate-Lactic Acidosis Study Group

BACKGROUND

Mortality is very high in lactic acidosis, and there is no satisfactory treatment other than treatment of the underlying cause. Uncontrolled studies have suggested that dichloroacetate, which stimulates the oxidation of lactate to acetyl-coenzyme A and carbon dioxide, might reduce morbidity and improve survival among patients with this condition.

METHODS

We conducted a placebo-controlled, randomized trial of intravenous sodium dichloroacetate therapy in 252 patients with lactic acidosis; 126 were assigned to receive dichloroacetate and 126 to receive placebo. The entry criteria included an arterial-blood lactate concentration of > or = 5.0 mmol per liter and either an arterial-blood pH of < or = 7.35 or a base deficit of > or = 6 mmol per liter. The mean (+/- SD) arterial-blood lactate concentrations before treatment were 11.6 +/- 7.0 mmol per liter in the dichloroacetate-treated patients and 10.4 +/- 5.5 mmol per liter in the placebo group, and the mean initial arterial-blood pH values were 7.24 +/- 0.12 and 7.24 +/- 0.13, respectively. Eighty-six percent of the patients required mechanical ventilation, and 74 percent required pressor agents, inotropic drugs, or both because of hypotension.

RESULTS

The arterial-blood lactate concentration decreased 20 percent or more in 83 (66 percent) of the 126 patients who received dichloroacetate and 45 (36 percent) of the 126 patients who received placebo (P = 0.001). The arterial-blood pH also increased more in the dichloroacetate-treated patients (P = 0.005). The absolute magnitude of the differences was small, however, and they were not associated with improvement in hemodynamics or survival. Only 12 percent of the dichloroacetate-treated patients and 17 percent of the placebo patients survived to be discharged from the hospital.

CONCLUSIONS

Dichloroacetate treatment of patients with severe lactic acidosis results in statistically significant but clinically unimportant changes in arterial-blood lactate concentrations and pH and fails to alter either hemodynamics or survival.

Inheritance of proliferative breast disease in breast cancer kindreds

Previous studies have emphasized that genetic susceptibility to breast cancer is rare and is expressed primarily as premenopausal breast cancer, bilateral breast cancer, or both. Proliferative breast disease (PBD) is a significant risk factor for the development of breast cancer and appears to be a precursor lesion. PBD and breast cancer were studied in 103 women from 20 kindreds that were selected for the presence of two first degree relatives with breast cancer and in 31 control women. Physical examination, screening mammography, and four-quadrant fine-needle breast aspirates were performed. Cytologic analysis of breast aspirates revealed PBD in 35% of clinically normal female first degree relatives of breast cancer cases and in 13% of controls. Genetic analysis suggests that genetic susceptibility causes both PBD and breast cancer in these kindreds. This study supports the hypothesis that this susceptibility is responsible for a considerable portion of breast cancer, including unilateral and postmenopausal breast cancer.

Evidence against the reported linkage of the cutaneous melanoma-dysplastic nevus syndrome locus to chromosome Ip36

The reported linkage between cutaneous melanoma and the dysplastic nevus syndrome (CM/DNS) to markers located on the distal portion of the short arm of chromosome 1 was examined in three Utah kindreds ascertained for multiple cases of melanoma. Family members in these kindreds were genotyped for the two markers reported to be most closely linked in the Bale study, PND and D1S47. Both melanoma alone and a combined melanoma/DNS phenotype were analyzed; no evidence for linkage was found. By multipoint linkage analysis the CM/DNS locus was excluded from an area of 55 cM containing the PND-D1S47 region. Diagnostic or genetic heterogeneity are alternate explanations for the discrepancy between our observations and those of Bale et al.

A genetic map of human chromosome 17p

A genetic linkage map was constructed with 18 loci from the short arm and pericentric region of chromosome 17 typed on the CEPH reference families. The genetic map includes three markers extracted from the CEPH public database. Nine loci could be ordered using a threshold of odds of at least 1000:1 against alternative orders during the map construction process. With a reduced tolerance of 100:1, a total of 13 loci could be placed on the map spanning a distance of approximately 60 cM in females and 46 cM in males. There were statistically significant differences between the male and the female genetic maps. The order inferred from the genetic data was consistent with the physical localizations of these probes obtained from somatic cell hybrids and tumor deletion studies. This map should be useful for genetic fine mapping of 17p loci.

A preliminary study on the timeliness of ambulatory care utilization following medical self-care interventions

A sub-sample, from a large prospective study examining the effects on utilization from the introduction of medical self-care materials, was followed to determine the timeliness of that utilization. Judgments on early, on time, or late visits, by patients, providers, and algorithms showed agreement for experimentals (n = 203) but not controls (n = 56). Comparisons on the rates of judged early, on time, and late visits differed between groups (by the physician and algorithm comparison), and further differed when comparing late only visits (by the algorithm comparison). The experimentals demonstrated a trend to delay care seeking though no adverse effect on health was identified when comparing subsequent illness days and hospitalizations. Medical self-care can reduce utilization and improve patients' ability to judge visit timeliness. Apparent trends to increase late visits may be an artifact of conservative judgments rendered by medical opinion.

Body weight in chronic obstructive pulmonary disease. The National Institutes of Health Intermittent Positive-Pressure Breathing Trial

This study reviews the relationship between body weight, pulmonary function, and survival in the recent clinical trial of intermittent positive pressure breathing (IPPB). We related body weight, expressed as a percent of the ideal (%IBW), to the numerous other features of the disease recorded in this data set. Body weight was directly related to FEV1 (p = 0.0001), so that all subsequent analyses of body weight had to first consider FEV1. Mortality appeared to be influenced by body weight independent of FEV1. In patients with %FEV1 less than 35, mortality increased with decreasing body weight (p = 0.093), and this relationship was stronger in patients with %FEV1 35 to 47 (p = 0.048) and even stronger in patients with %FEV1 greater than 47 (p = 0.007). After adjusting for FEV1, body weight was a powerful positive correlate with exercise capacity (p = 0.0001). Body weight was also inversely related to %TLC (p = 0.0408) after adjusting for FEV1. Body weight was a powerful predictor of diffusing capacity (p = 0.0001) in patients with the same FEV1. These results support the hypothesis that factors related to nutritional status are an independent influence on the course of COPD.