Distributional Properties and Criterion Validity of a Shortened Version of the Social Responsiveness Scale: Results from the ECHO Program and Implications for Social Communication Research

Prior work proposed a shortened version of the Social Responsiveness Scale (SRS), a commonly used quantitative measure of social communication traits. We used data from 3031 participants (including 190 ASD cases) from the Environmental Influences on Child Health Outcomes (ECHO) Program to compare distributional properties and criterion validity of 16-item “short” to 65-item “full” SRS scores. Results demonstrated highly overlapping distributions of short and full scores. Both scores separated case from non-case individuals by approximately two standard deviations. ASD prediction was nearly identical for short and full scores (area under the curve values of 0.87, 0.86 respectively). Findings support comparability of shortened and full scores, suggesting opportunities to increase efficiency. Future work should confirm additional psychometric properties of short scores.

     

Rituximab and three dexamethasone cycles provide responses similar to splenectomy in women and those with immune thrombocytopenia of less than two years duration

Adults with newly diagnosed or persistent immunothrombocytopenia frequently relapse upon tapering steroids; adults and children with chronic disease have an even lower likelihood of lasting response. In adults with newly-diagnosed immunothrombocytopenia, two studies showed that dexamethasone 40 mg/day × four days and 4 rituximab infusions were superior to dexamethasone alone. Studies have also shown three cycles of dexamethasone are better than one and patients with persistent/chronic immunothrombocytopenia respond less well to either dexamethasone or rituximab. Therefore, 375 mg/m² × 4 rituximab was combined with three 4-day cycles of 28 mg/m² (max. 40 mg) dexamethasone at 2-week intervals and explored in 67 ITP patients. Best long-term response was assessed as complete (platelet count ≥100×10⁹/L) or partial (50–99×10⁹/L). Only 5 patients had not been previously treated. Fifty achieved complete (n=43, 64%) or partial (n=7, 10%) responses. Thirty-five of 50 responders maintained treatment-free platelet counts over 50×10⁹/L at a median 17 months (range 4–67) projecting 44% event-free survival. Duration of immunothrombocytopenia less than 24 months, achieving complete responses, and being female were associated with better long-term response (P<0.01). Adverse events were generally mild-moderate, but 3 patients developed serum sickness and 2 colitis; there were no sequelae. Dexamethasone could be difficult to tolerate. Fourteen patients became hypogammaglobulinemic and half had increased frequency of minor infections; 9 of 12 evaluable patients recovered their IgG levels. Rituximab combined with three cycles of dexamethasone provides apparently better results to reported findings with rituximab alone, dexamethasone alone, or the combination with one cycle of dexamethasone. The results suggest medical cure may be achievable in immunothrombocytopenia, especially in women and in patients within two years of diagnosis. (clinicaltrials.gov identifier:02050581)     

Defining accelerometer thresholds for activity intensities in adolescent girls

PURPOSE: To derive a regression equation that estimates metabolic equivalent (MET) from accelerometer counts, and to define thresholds of accelerometer counts that can be used to delineate sedentary, light, moderate, and vigorous activity in adolescent girls. METHODS: Seventy-four healthy 8th grade girls, age 13 - 14 yr, were recruited from urban areas of Baltimore, MD, Minneapolis/St. Paul, MN, and Columbia, SC, to participate in the study. Accelerometer and oxygen consumption (.-)VO(2)) data for 10 activities that varied in intensity from sedentary (e.g., TV watching) to vigorous (e.g., running) were collected. While performing these activities, the girls wore two accelerometers, a heart rate monitor and a Cosmed K4b2 portable metabolic unit for measurement of (.-)VO(2). A random-coefficients model was used to estimate the relationship between accelerometer counts and (.-)VO(2). Activity thresholds were defined by minimizing the false positive and false negative classifications. RESULTS: The activities provided a wide range in (.-)VO(2) (3 - 36 mL x kg x min) with a correspondingly wide range in accelerometer counts (1- 3928 counts x 30 s). The regression line for MET score versus counts was MET = 2.01 +/- 0.00171 (counts x 30 s) (mixed model R = 0.84, SEE = 1.36). A threshold of 1500 counts x 30 s defined the lower end of the moderate intensity (approximately 4.6 METs) range of physical activity. That cutpoint distinguished between slow and brisk walking, and gave the lowest number of false positive and false negative classifications. The threshold ranges for sedentary, light, moderate, and vigorous physical activity were found to be 0 - 50, 51- 1499, 1500 - 2600, and >2600 counts x 30 s, respectively. CONCLUSION: The developed equation and these activity thresholds can be used for prediction of MET score from accelerometer counts and participation in various intensities of physical activity in adolescent girls.     

A prospective study of coronary heart disease and the hemochromatosis gene (HFE) C282Y mutation: the Atherosclerosis Risk in Communities (ARIC) study

Increased iron stores may play a role in the development of coronary heart disease (CHD) by increasing lipoprotein oxidation. Recently, mutations have been discovered in the gene (HFE) for hereditary hemochromatosis, an autosomal recessive condition of disordered iron metabolism, absorption, and storage. It is possible that people who carry HFE mutations have increased risk of CHD. We used a prospective case-cohort design (243 CHD cases and 535 non-cases) to determine whether the HFE C282Y mutation was associated with incident CHD in a population-based sample of middle-aged men and women. The frequencies of homozygosity and heterozygosity for the C282Y mutation in the ARIC study population were 0.2% (one homozygous person) and 6%, respectively. The C282Y mutation was associated with nonsignificantly increased risk of CHD (relative risk=1.60, 95% CI 0.9-2.9). After adjusting for other confounding risk factors (age, race, gender, ARIC community, smoking status, diabetes status, hypertension status, LDL cholesterol, HDL cholesterol, and triglycerides), the association became stronger (relative risk=2.70, 95% CI 1.2-6.1). However, a sensitivity analysis showed that this estimate of relative risk was somewhat unstable due to few subjects in some strata. Our prospective findings suggest that individuals carrying the HFE C282Y mutation may be at increased risk of CHD.     

Depression as a risk factor for mortality after acute myocardial infarction

The ENRICHD clinical trial, which compared an intervention for depression and social isolation to usual care, failed to decrease the rate of mortality and recurrent acute myocardial infarction (AMI) in post-AMI patients. One explanation for this is that depression was not associated with increased mortality in these patients. The purpose of this study was to determine if depression was associated with an increased risk of mortality in a subsample of the ENRICHD trial's depressed patients compared with a group of nondepressed patients recruited for an ancillary study. Three hundred fifty-eight depressed patients with an acute AMI from the ENRICHD clinical trial and 408 nondepressed patients who met the ENRICHD medical inclusion criteria were followed for up to 30 months. There were 47 deaths (6.1%) and 57 nonfatal AMIs (7.4%). After adjusting for other risk factors, depressed patients were at higher risk for all-cause mortality (hazard ratio 2.4, 95% confidence interval 1.2 to 4.7) but not for nonfatal recurrent infarction (hazard ratio 1.2, 95% confidence interval 0.7 to 2.0) compared with nondepressed patients. In conclusion, depression was an independent risk factor for death after AMI, but it did not have a significant effect on mortality until nearly 12 months after the acute event, nor did it predict nonfatal recurrent infarction.     

Human leukocyte antigen mismatches predispose to the severity of bronchiolitis obliterans syndrome after lung transplantation

BACKGROUND: Obliterative bronchiolitis (OB) is the most important cause of long-term morbidity and mortality in lung transplant recipients, and probably results from alloimmune airway injury. Bronchiolitis obliterans syndrome (BOS), defined as a staged decline in pulmonary function, is the clinical correlate of OB. OBJECTIVE: Evaluation of the risk and severity of BOS on the basis of the incompatibility of donor and recipient human leukocyte antigen (HLA) molecules. DESIGN: Retrospective cohort study. SETTING: Large university hospital. PARTICIPANTS: Lung transplant recipients between January 1990 and January 2000. MEASUREMENTS: We determined the BOS stage using internationally promulgated guidelines with a minor modification on all recipients at their 4-year transplant anniversary. Recipients whose graft function had deteriorated or who died due to causes other than BOS were excluded from the study. HLA loci mismatches and other covariables, including recipient age, donor age, cytomegalovirus (CMV) mismatch, cold ischemic time, use of cardiopulmonary bypass, ventilatory days, episodes of acute rejection and CMV pneumonitis, mean trough cyclosporin A (CsA) level, episodes of subtherapeutic CsA levels, and histopathology of OB and diffuse alveolar damage were entered into the analysis of BOS predictors. RESULTS: Sixty-four patients met the inclusion and exclusion criteria of the study at the 4-year posttransplant time point. In univariate analyses, the number of combined HLA-A and HLA-B mismatches was strongly associated with the stage of BOS at 4 years (p = 0.002). This association remained significant after the inclusion of other potential risk factors for BOS in multiple linear regression models. Pretransplant and posttransplant proportional odds models confirmed that the increasing number of combined HLA-A and HLA-B mismatches increased the overall severity of BOS (adjusted odds ratio, 1.84 [p = 0.035] vs 1.69 [p = 0.067], respectively). A trend toward significance was seen with HLA-DR mismatching (p = 0.17). CONCLUSIONS: The degree of HLA class I mismatching between donors and recipients predisposes lung transplant recipients to the development and severity of BOS.     

Effects of treating depression and low perceived social support on clinical events after myocardial infarction: the Enhancing Recovery in Coronary Heart Disease Patients (ENRICHD) Randomized Trial

Context  Depression and low perceived social support (LPSS) after myocardial infarction (MI) are associated with higher morbidity and mortality, but little is known about whether this excess risk can be reduced through treatment. Objective  To determine whether mortality and recurrent infarction are reduced by treatment of depression and LPSS with cognitive behavior therapy (CBT), supplemented with a selective serotonin reuptake inhibitor (SSRI) antidepressant when indicated, in patients enrolled within 28 days after MI. Design, Setting, and Patients  Randomized clinical trial conducted from October 1996 to April 2001 in 2481 MI patients (1084 women, 1397 men) enrolled from 8 clinical centers. Major or minor depression was diagnosed by modified Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition criteria and severity by the 17-item Hamilton Rating Scale for Depression (HRSD); LPSS was determined by the Enhancing Recovery in Coronary Heart Disease Patients (ENRICHD) Social Support Instrument (ESSI). Random allocation was to usual medical care or CBT-based psychosocial intervention. Intervention  Cognitive behavior therapy was initiated at a median of 17 days after the index MI for a median of 11 individual sessions throughout 6 months, plus group therapy when feasible, with SSRIs for patients scoring higher than 24 on the HRSD or having a less than 50% reduction in Beck Depression Inventory scores after 5 weeks. Main Outcome Measures  Composite primary end point of death or recurrent MI; secondary outcomes included change in HRSD (for depression) or ESSI scores (for LPSS) at 6 months. Results  Improvement in psychosocial outcomes at 6 months favored treatment: mean (SD) change in HRSD score, -10.1 (7.8) in the depression and psychosocial intervention group vs -8.4 (7.7) in the depression and usual care group (P<.001); mean (SD) change in ESSI score, 5.1 (5.9) in the LPSS and psychosocial intervention group vs 3.4 (6.0) in the LPSS and usual care group (P<.001). After an average follow-up of 29 months, there was no significant difference in event-free survival between usual care (75.9%) and psychosocial intervention (75.8%). There were also no differences in survival between the psychosocial intervention and usual care arms in any of the 3 psychosocial risk groups (depression, LPSS, and depression and LPSS patients). Conclusions  The intervention did not increase event-free survival. The intervention improved depression and social isolation, although the relative improvement in the psychosocial intervention group compared with the usual care group was less than expected due to substantial improvement in usual care patients.