Wireless phone use in childhood and adolescence and neuroepithelial brain tumours: Results from the international MOBI-Kids study

In recent decades, the possibility that use of mobile communicating devices, particularly wireless (mobile and cordless) phones, may increase brain tumour risk, has been a concern, particularly given the considerable increase in their use by young people. MOBI-Kids, a 14-country (Australia, Austria, Canada, France, Germany, Greece, India, Israel, Italy, Japan, Korea, the Netherlands, New Zealand, Spain) case-control study, was conducted to evaluate whether wireless phone use (and particularly resulting exposure to radiofrequency (RF) and extremely low frequency (ELF) electromagnetic fields (EMF)) increases risk of brain tumours in young people. Between 2010 and 2015, the study recruited 899 people with brain tumours aged 10 to 24 years old and 1,910 controls (operated for appendicitis) matched to the cases on date of diagnosis, study region and age. Participation rates were 72% for cases and 54% for controls. The mean ages of cases and controls were 16.5 and 16.6 years, respectively; 57% were males. The vast majority of study participants were wireless phones users, even in the youngest age group, and the study included substantial numbers of long-term (over 10 years) users: 22% overall, 51% in the 20-24-year-olds. Most tumours were of the neuroepithelial type (NBT; n = 671), mainly glioma. The odds ratios (OR) of NBT appeared to decrease with increasing time since start of use of wireless phones, cumulative number of calls and cumulative call time, particularly in the 15-19 years old age group. A decreasing trend in ORs was also observed with increasing estimated cumulative RF specific energy and ELF induced current density at the location of the tumour. Further analyses suggest that the large number of ORs below 1 in this study is unlikely to represent an unknown causal preventive effect of mobile phone exposure: they can be at least partially explained by differential recall by proxies and prodromal symptoms affecting phone use before diagnosis of the cases. We cannot rule out, however, residual confounding from sources we did not measure. Overall, our study provides no evidence of a causal association between wireless phone use and brain tumours in young people. However, the sources of bias summarised above prevent us from ruling out a small increased risk.

Metabolomics and cancer preventive behaviors in the BC Generations Project

Metabolomics can detect metabolic shifts resulting from lifestyle behaviors and may provide insight on the relevance of changes to carcinogenesis. We used non-targeted nuclear magnetic resonance to examine associations between metabolic measures and cancer preventive behaviors in 1319 participants (50% male, mean age 54 years) from the BC Generations Project. Behaviors were dichotomized: BMI < 25 kg/m², ≥ 5 servings of fruits or vegetables/day, ≤ 2 alcoholic drinks/day for men or 1 drink/day for women and ≥ 30 min of moderate or vigorous physical activity/day. Linear regression was used to estimate coefficients and 95% confidence intervals with a false discovery rate (FDR) of 0.10. Of the 218 metabolic measures, 173, 103, 71 and 6 were associated with BMI, fruits and vegetables, alcohol consumption and physical activity. Notable findings included negative associations between glycoprotein acetyls, an inflammation-related metabolite with lower BMI and greater fruit and vegetable consumption, a positive association between polyunsaturated fatty acids and fruit and vegetable consumption and positive associations between high-density lipoprotein subclasses with lower BMI. These findings provide insight into metabolic alterations in the context of cancer prevention and the diverse biological pathways they are involved in. In particular, behaviors related to BMI, fruit and vegetable and alcohol consumption had a large metabolic impact.

Abstract P6-13-04: Estrogen-alone based hormone replacement therapy (HRT) reduces breast cancer (BrCa) incidence and mortality whereas estrogen plus progestin Provera based HRT increases both BrCa incidence and BrCa mortality: A comparative analysis of Women's Health Initiative trials

OBJECTIVE: To quantitate breast cancer incidence (BrCa-I) and mortality (BrCa-M) outcome differences between the two Women's Health Initiative (WHI) HRT trials,1,2 the ratio of hazards was calculated for estrogen-alone based hormone replacement therapy (E-HRT) vs. placebo (P), and E + progestin Provera (ProgProv) combination HRT vs. P trials.

METHODS: Hazard ratios (HR) of BrCa-I and BrCa-M and 95% confidence intervals (CI) were obtained from both WHI HRT trials. Subsequently, to compare BrCa outcomes between E-HRT vs. E + ProgProv, the ratios of HRs between the trials (HR1/HR2) were estimated separately for i. BrCa-I all women, ii. BrCa-I low Gail score (Gail score &lt;1.75*), and iii. BrCa-M. The 95% CI was derived through logarithmic transformation of the 95% CI originally reported.

RESULTS:

Outcome Comparison, the two WHI HRT randomized trials. Ratio of Hazards, BrCa Incidence and BrCa mortality E-HRT vs. P, HR1 (95% CI)E-HRT + ProgProv vs. P, HR2 (95% CI)HR1/HR2 (95% CI)pBrCa-I All Woman10.77 (0.62-0.95)1.25 (1.07-1.46)0.62 (0.47-0.80)0.0004BrCa-I Low Gail Score* (Gail score &lt;1.75)10.65 (0.50-0.86)1.24 (1.01-1.51)0.53 (0.38-0.74)0.0002BrCa-M20.55 (0.33-0.92)1.44 (0.97-2.15)0.38 (0.20-0.75)0.004*Gail score &lt;1.75; HRs calculated from Reference 1, Figure 3

CONCLUSIONS: Our calculations show that the different outcomes between the two WHI HRT trials, estimated as ratio of hazards, are highly significant on statistical basis, both for BrCa incidence and for BrCa mortality. These findings highlight the potential carcinogenic impact of ProgProv and the major public health benefits of HRT based on E alone.

REFERENCES:

1. Anderson GL, Chlebowski RT, Aragaki AK, et al. Conjugated equine oestrogen and breast cancer incidence and mortality in postmenopausal women with hysterectomy: extended follow-up of the Women's Health Initiative randomised placebo-controlled trial. The Lancet Oncology 2012;13:476-86.

2. Manson JE, Aragaki AK, Rossouw JE, et al. Menopausal Hormone Therapy and Long-term All-Cause and Cause-Specific Mortality: The Women's Health Initiative Randomized Trials. JAMA 2017;318:927-38.

Citation Format: Ragaz J, Qian H, Wong H, Wilson KS, Shakeraneh S, Spinelli JJ. Estrogen-alone based hormone replacement therapy (HRT) reduces breast cancer (BrCa) incidence and mortality whereas estrogen plus progestin Provera based HRT increases both BrCa incidence and BrCa mortality: A comparative analysis of Women's Health Initiative trials [abstract]. In: Proceedings of the 2018 San Antonio Breast Cancer Symposium; 2018 Dec 4-8; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2019;79(4 Suppl):Abstract nr P6-13-04.

Abstract P6-13-06: Estrogen-based hormone replacement [HRT] therapy is substantially more effective than tamoxifen in reducing breast cancer mortality and breast cancer case fatality ratio: Emergence of a new paradigm

OBJECTIVE: To compare, in the setting of breast cancer (BrCa) prevention, the impact of estrogen-based hormone replacement therapy (E-HRT) vs. tamoxifen (TAM) on breast cancer mortality (BrCa-M) and breast cancer case fatality ratio (BrCa-CFR), by analyzing data from the Women's Health Initiative Trial 2 (WHI HRT Trial 2, E-HRT vs. placebo [P])1 and the International Breast Cancer Intervention Study 1 (IBIS-1), TAM vs. P.2

METHODS: Hazard ratios (HR) and confidence intervals (CI) for BrCa incidence and mortality were extracted from the original WHI HRT Trial 2 and IBIS-1 trials.1,2 BrCa-CFRs were estimated by dividing the mortality HR by the incidence HR. Subsequently, to compare E-HRT vs. TAM outcomes, the ratios of HRs (HR1/HR2) between the two trials were estimated separately for BrCa-M and BrCa-CFR. The 95% CI was derived through logarithmic transformation of the 95% CI originally reported.

RESULTS:

Mortality and Case Fatality Outcomes: Impact of E-HRT versus TAM, expressed as ratio of HRs E-HRT vs. Placebo, HR1TAM vs. Placebo, HR2HR1/HR2pMortality0.55 (0.33-0.92)1.19 (0.68-2.10)0.46 (0.22-0.99)0.046Case Fatality0.70 (0.40-1.20)1.68 (0.93-3.01)0.42 (0.18-0.94)0.040

CONCLUSIONS: While acknowledging between-trial comparisons including eligibility differences, E-HRT yields significant reductions in BrCa mortality and case fatality as compared with TAM (54% and 58% respectively). These unexpected breast cancer mortality reductions represent major public health gains, additional to the already known superiority of E-HRT over TAM in terms of skeletal fracture rates and Alzheimer's dementia mortality reduction, and, in women entering menopause, also of cardiac and all-cause mortality reductions.

REFERENCES:

1. Manson JE, Aragaki AK, Rossouw JE, et al. Menopausal Hormone Therapy and Long-term All-Cause and Cause-Specific Mortality: The Women's Health Initiative Randomized Trials. JAMA 2017;318:927-38.

2. Cuzick J, Sestak I, Cawthorn S, et al. Tamoxifen for prevention of breast cancer: extended long-term follow-up of the IBIS-I breast cancer prevention trial. The Lancet Oncology 2015;16:67-75.

Citation Format: Ragaz J, Shakeraneh S, Qian H, Wilson KS, Wong H, Spinelli JJ. Estrogen-based hormone replacement [HRT] therapy is substantially more effective than tamoxifen in reducing breast cancer mortality and breast cancer case fatality ratio: Emergence of a new paradigm [abstract]. In: Proceedings of the 2018 San Antonio Breast Cancer Symposium; 2018 Dec 4-8; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2019;79(4 Suppl):Abstract nr P6-13-06.

Utilization of bone mineral density testing among breast cancer survivors in British Columbia, Canada

Breast cancer survivors are at high osteoporosis risk. Bone mineral density testing plays a key role in osteoporosis management. We analyzed a historical utilization of bone mineral density testing in breast cancer survivors. The utilization remained low in the 1995-2008 period. Lower socio-economic status and rural residency were associated with lower utilization.

INTRODUCTION

To evaluate the utilization of bone mineral density (BMD) testing for female breast cancer survivors aged 65+ surviving ≥ 3 years in British Columbia, Canada.

METHODS

A retrospecitve population-based data linkage study. Trends in proportion of survivors with ≥ 1 BMD test for each calendar year from 1995 to 2008 were evaluated with a serial cross-sectional analysis. Associations between factors (socio-demographic and clinical) and BMD testing rates over the period 2006-2008 for 7625 survivors were evaluated with a cross-sectional analysis and estimated as adjusted prevalence ratios (PR_adj) using log-binomial models.

RESULTS

Proportions of survivors with ≥ 1 BMD test increased from 1.0% in 1995 to 10.1% in 2008. The BMD testing rate in 2006-2008 was 26.5%. Socio-economic status (SES) and urban/rural residence were associated with BMD testing rates in a dose-dependent relationship (p for trend< 0.01). Survivors with lower SES (PR_adj = 0.66-0.78) or rural residence (PR_adj = 0.70) were 20-30% less likely to have BMD tests, compared with survivors with the highest SES or urban residence. BMD testing rates were also negatively associated with older age (75+) (PR_adj = 0.47; 95% CI = 0.42, 0.52), nursing home residency (0.05; 0.01, 0.39), recent osteoporotic fractures (0.21; 0.14, 0.32), and no previous BMD tests (0.26; 0.23, 0.29).

CONCLUSION

Utilization of BMD testing was low for breast cancer survivors in BC, Canada. Lower SES and rural residence were associated with lower BMD testing rates.

IMPLICATION FOR CANCER SURVIVORS

Female breast cancer survivors, especially those with lower SES or rural residence, should be encouraged to receive BMD tests as recommended by Canadian guidelines.

Fluid intake and hydration status in obese vs normal weight children

BACKGROUND/OBJECTIVES

Little is known on the relationship between obesity and hydration levels in children. This study assessed whether and by which mechanisms hydration status differs between obese and non-obese children.

SUBJECTS/METHODS

Hydration levels of 86 obese and 89 normal weight children (age: 7-11 years) were compared. Hydration was measured as the average free water reserve (FWR=urine output/24 h minus the obligatory urine output [total 24 h excreted solutes/97th percentile of urine osmolality of children with adequate water intake, that is, 830 mOsm/kg]) over 2 days. Three days of weighed dietary and fluid intakes were recorded. Non-parametric tests were used to compare variables that were skewed and to assess which variables correlated with hydration. Variables mediating the different hydration levels of obese and normal weight children were assessed by co-variance analysis.

RESULTS

Obese children were less hydrated than normal weight peers [FWR=median (IQR): 0.80 (-0.80-2.80) hg/day vs 2.10 (0.10-4.45) hg/day, P<0.02; 32% of obese children vs 20% of non-obese peers had negative FWR, P<0.001]. Body mass index (BMI) z-score (z-BMI) and water intake from fluids correlated with FWR (ρ=-0.18 and 0.45, respectively, both P<0.05). Water intake from fluids completely explained the different hydration between obese and normal weight children [FWR adjusted for water from fluids and z-BMI=2.44 (0.44) hg vs 2.10 (0.50) hg, P=NS; B coefficient of co-variation between FWR (hg/day) and water intake from fluids (hg/day)=0.47, P<0.001].

CONCLUSIONS

Obese children were less hydrated than normal weight ones because, taking into account their z-BMI, they drank less. Future prospective studies are needed to explore possible causal relationships between hydration and obesity.

Is early discharge safe after naloxone reversal of presumed opioid overdose?

Introduction:

Patients with suspected opioid overdose frequently require naloxone treatment. Despite recommendations to observe such patients for 4 to 24 hours after naloxone, earlier discharge is becoming more common. This prospective, observational study of patients with presumed opioid overdose examines the safety of early disposition decisions and the accuracy of outcome prediction by physicians 1 hour after the administration of naloxone.

Methods:

The study was carried out at St. Paul’s Hospital, an inner city teaching centre that cares for most of the injection drug users in Vancouver, BC. Patients were formally assessed 1 hour after receiving naloxone for presumed opioid overdose. Demographics, medical history and physical examination were documented on specific data forms, and physicians recorded their comfort with early discharge. Patients were followed up, and those who required a critical intervention or suffered a pre-defined adverse event (AE) within 24 hours of their 1-hour assessment were identified.

Results:

Of 573 patients, 48% were discharged in less than 2 hours, 23% in 2–4 hours and 29% in &gt;4 hours. 94 patients who were held in the emergency department (ED) or admitted required a critical intervention, including supplemental oxygen for hypoxia (74), repeat naloxone (52), antibiotics administered intravenously (IV) (14), assisted ventilations (13), fluid bolus for hypotension (12), charcoal for associated life-threatening overdose (6), IV inotropic agents (2), antiarrhythmics for sustained tachycardia &gt;130 beats/min (1), and administration of bicarbonate for arterial [HCO3] &lt;5 or venous CO2 &lt;5 (1). Physicians predicted adverse events with 94% sensitivity and 59% specificity. No discharged patients suffered a serious AE within 24 hours of ED discharge.

Conclusions:

Emergency physicians can clinically identify patients at risk of deterioration after naloxone reversal of suspected opioid overdose. Prolonged observation or hospital admission is not usually required. Selective early discharge of patients with presumed opioid overdose is feasible and appears safe. A clinical prediction rule may be useful in identifying patients eligible for early discharge.

Medical role of first responders in an urban prehospital setting

Background:

Almost all North American cities have first responder programs. To date there is no published documentation of the roles first responders play, nor of the frequency and type of interventions they perform. Many urban stakeholders question the utility and safety of routinely dispatching large vehicles emergently to calls that may not require their services. Real world data on first responder interventions will help emergency medical services (EMS) directors and planners determine manpower requirements, assess training needs, and optimize dispatch protocols to reduce the rate of inappropriate “code 3” (lights and siren) responses.

Objective:

Our objectives were to determine how often first responders arrive first on scene, to estimate the time interval between first response and EMS response, and to examine the frequency and type of interventions performed by first responders.

Methods:

In a prospective observational study, trained observers were assigned to fire department first responder (FDFR) units. These observers recorded on-scene times for FDFR and EMS units, and documented the performance of first responder interventions.

Results:

FDFRs arrived first on scene in 49% of code 3 calls. They performed critical interventions in 18% of calls attended and 36% of calls where they arrived first. Oxygen administration was the most frequent critical intervention, yet occult hypoxemia was common and compliance with oxygen administration protocols was poor.

Conclusions:

First responders perform critical interventions during a minority of code 3 calls, even when “critical” is defined generously. Many “lights and siren” dispatches are unnecessary. Future research should attempt to identify dispatch criteria that more accurately predict the need for first responder intervention. First responder training and continuous quality improvement (CQI) should focus on interventions that are performed with some regularity, particularly oxygen administration.

Cigarette smoking and risk of Hodgkin lymphoma and its subtypes: a pooled analysis from the International Lymphoma Epidemiology Consortium (InterLymph)

BACKGROUND

The etiology of Hodgkin lymphoma (HL) remains incompletely characterized. Studies of the association between smoking and HL have yielded ambiguous results, possibly due to differences between HL subtypes.

PATIENTS AND METHODS

Through the InterLymph Consortium, 12 case-control studies regarding cigarette smoking and HL were identified. Pooled analyses on the association between smoking and HL stratified by tumor histology and Epstein-Barr virus (EBV) status were conducted using random effects models adjusted for confounders. Analyses included 3335 HL cases and 14 278 controls.

RESULTS

Overall, 54.5% of cases and 57.4% of controls were ever cigarette smokers. Compared with never smokers, ever smokers had an odds ratio (OR) of HL of 1.10 [95% confidence interval (CI) 1.01-1.21]. This increased risk reflected associations with mixed cellularity cHL (OR = 1.60, 95% CI 1.29-1.99) and EBV-positive cHL (OR = 1.81, 95% CI 1.27-2.56) among current smokers, whereas risk of nodular sclerosis (OR = 1.09, 95% CI 0.90-1.32) and EBV-negative HL (OR = 1.02, 95% CI 0.72-1.44) was not increased.

CONCLUSION

These results support the notion of etiologic heterogeneity between HL subtypes, highlighting the need for HL stratification in future studies. Even if not relevant to all subtypes, our study emphasizes that cigarette smoking should be added to the few modifiable HL risk factors identified.

Postmenopausal hormone therapy and non-Hodgkin lymphoma: a pooled analysis of InterLymph case-control studies

BACKGROUND

Non-Hodgkin lymphoma (NHL) subtypes, diffuse large B-cell (DLBCL) and follicular lymphoma (FL) have different sex ratios and are diagnosed at ages over 60 years; DLBCL is more common in men and diagnosed at older ages than FL, which occurs more among women. This analysis of postmenopausal women examines the relationship between postmenopausal hormone therapy and NHL.

DESIGN

Self-reported use of postmenopausal hormone therapy from 2094 postmenopausal women with NHL and 2731 without were pooled across nine case-control studies (1983-2005) from North America, Europe and Japan. Study-specific odds ratios (OR) and 95% confidence intervals (CI) estimated using logistic regression were pooled using random-effects meta-analyses.

RESULTS

Postmenopausal women who used hormone therapy were at decreased risk of NHL (pooled OR = 0.79, 95% CI 0.69-0.90). Risks were reduced when the age of starting was 50 years or older. There was no clear trend with number of years of use. Current users were at decreased risk while those stopping over 2 years before diagnosis were not. Having a hysterectomy or not did not affect the risk. Favourable effects were present for DLBCL (pooled OR = 0.66, 95% CI 0.54-0.80) and FL (pooled OR = 0.82, 95% CI 0.66-1.01).

CONCLUSION

Postmenopausal hormone therapy, particularly used close to menopause, is associated with a decreased risk of NHL.

Menstrual and reproductive factors, and hormonal contraception use: associations with non-Hodgkin lymphoma in a pooled analysis of InterLymph case-control studies

BACKGROUND

The two most common forms of non-Hodgkin lymphoma (NHL) exhibit different sex ratios: diffuse large B-cell lymphoma (DLBCL) occurs more frequently in men and follicular lymphoma (FL) more frequently in women. Looking among women alone, this pooled analysis explores the relationship between reproductive histories and these cancers.

MATERIALS AND METHODS

Self-reported reproductive histories from 4263 women with NHL and 5971 women without NHL were pooled across 18 case-control studies (1983-2005) from North America, Europe and Japan. Study-specific odd ratios (ORs) and confidence intervals (CIs) were estimated using logistic regression and pooled using random-effects meta-analyses.

RESULTS

Associations with reproductive factors were found for FL rather than NHL overall and DLBCL. In particular, the risk of FL decreased with increasing number of pregnancies (pooled OR(trend) = 0.88, 95% CI 0.81-0.96). FL was associated with hormonal contraception (pooled OR = 1.30, 95% CI 1.04-1.63), and risks were increased when use started after the age of 21, was used for <5 years or stopped for >20 years before diagnosis. DLBCL, on the other hand, was not associated with hormonal contraception (pooled OR = 0.87, 95% CI 0.65-1.16).

CONCLUSIONS

Hormonal contraception is associated with an increased risk of FL but not of DLBCL or NHL overall.

Protective Effect of Estrogen (E2) and Increased Risk of E2 Plus Progestin (Prog) on Breast Cancer (BrCa). The 2009 Review of the Women's Health Initiative (WHI) Hormone Replacement Therapy (HRT) Published Trials

INTRODUCTION & METHODOLOGY.The objective of this review is to identify from the two WHI published randomized HRT trials the BrCa risk or benefit, with a special focus on different impact of E2-alone vs E2+Prog on human breast carcinogenesis (BrCa-genesis).In the 1st trial (JAMA 2002, 2007), healthy women age 50 - 79 were randomized to E2 plus Prog versus placebo (Plac). Reviewed were Hazard ratios (HRs) for all pts and also for those with or without prior Hormone use. Mean follow up was 5.2 years.In the 2nd trial (JAMA 2004, 2006), women with hysterectomy age 50 - 79 were randomized to E2 alone (without Prog) versus Plac. Mean follow up was 7.1 years. Reviewed were all pts, and also subsets with or without prior E2 or Prog; with or without prior history of Benign Breast Disease (PHBrD); and with or without prior history of a 1st degree relative with BrCa (PH1stRelBrCa).RESULTS.Invasive BrCa incidence:N (%)HR95% C.I.1st TrialAll participants:16,608 (100%)1.260.83 - 1.97No prior Hormone use:12,304 (74.1%)1.060.81 - 1.38Prior Hormone use &lt;5 yrs:3,005 (18.1%)2.131.15 - 3.94*Prior Hormone use 5 - 10 yrs:783 (4.7%)4.611.01 - 21.02*2nd TrialAll participants:10,739 (100%)0.800.62 - 1.04No prior hormone use:5,763 (53.7%)0.650.46 - 0.92*Prior E2 use:4,976 (46.3%)0.980.67 - 1.44Prior E2 + PROG use:468 (4.4%)2.350.60 - 9.14No PHBrD:7,681 (71.5%)0.570.41 - 0.78*No PH1stRelBrCa8,554 (80.0%)0.680.50 - 0.92*CONCLUSION:1. Results from the 1st trial show that concomitant use of E2 with Prog, particularly in women with prior Hormone use, is associated with increased BrCa hazards.2. The results of the 2nd HRT trial indicate that use of HRT with E2 alone is associated with a reduction in BrCa incidence, significant in the majority of women with no prior BrCa risk factors. Also the results show that prior Prog but not prior E2 elevate the risk.3. These data indicate that HRT with E2 alone has a BrCa protective effect, while adding Prog increases the risk.4. These results are also compatible with a dual E2 effect on BrCa-genesis, where exogenous E2 are protective, but endogenous E2 [endE2] are carcinogenic, as shown from decades of anti-end E2 research with Tamoxifen, oophorectomy or Aromatase inhibitors.5. Based on these data we propose that in women with hysterectomy and no prior history of risk factors, the use of HRT with E2 alone as chemoprevention is plausible, and needs urgent verification.* significance, "p" &lt;0.05.

Citation Information: Cancer Res 2009;69(24 Suppl):Abstract nr 908.

Childhood, adolescent, and young adult cancer survivors (CAYACS) research program of British Columbia: Data linkage: Results to date

9555

Background: Long-term survivors of childhood and adolescent cancers are at risk for late mortality and morbidity. Using database linkages we assessed the extent of these issues and health care utilization in a population based cohort in British Columbia. Methods: Retrospective cohorts of 3,483 survivors (>5 years from diagnosis), and representative comparison groups, have been identified from population-based registries. Linkages were made with administrative databases of risk factors and outcomes. Late mortality, second cancers, late morbidity, health services utilization, continuity of care, and educational outcomes, among those diagnosed before age 20 between 1970 to 1995, and followed to 2000, have been examined. Results: Survivors experienced a 9-fold increase in mortality (SMR 9.1, 95% CI 7.8–10.5). Risk of developing a second cancer was 5 times higher than in the general population (SIR 5.0, 95% CI 3.8–6.5). Survivors had three times the odds of being hospitalized (OR 2.97, 95% CI 2.56–3.45) in a three-year period (1998–2000). Survivors were significantly more likely than the population group to consult any physician (excluding oncologists) (adj. RR 1.61, 95% CI 1.51–1.70). Survivors were found to experience a drop in continuity of primary health care as they aged and transitioned into adult care. Survivors were significantly more likely than their peers to receive special education (32.5% vs. 14.1%), most significantly among CNS survivors who received cranial irradiation. Conclusions: Survivors of childhood and adolescent cancers have severe long term health issues and increased health care utilization. Survivors of CNS tumors were at highest risk of poor health and educational outcomes measured. Data linkage provides useful insights for survivorship research.

No significant financial relationships to disclose.

Breast cancer mortality reduction in the western world: therapeutic versus diagnostic interventions. Implications for cancer care organization processes

Abstract #6083

INTRODUCTION. Recent epidemiology data show a substantial Breast Cancer (BrCa) mortality reduction in the western countries over the last decade. The literature indicates that both Adjuvant systemic treatments (Adj. SystTh) and Screening mammography (ScrM) contribute, but their interaction is not clear.&#x2028; Our study examines if contribution of Adj. SystTh separate from ScrM could be more clearly identified; and also, - as a second objective, - if organization of cancer care could be correlated with BrCa mortality outcomes.&#x2028; METHODOLOGY:&#x2028; The mortality trends were compared among three Provinces of Canada with different Levels of Provincial Diagnostic and Therapy Guidelines (PDTG):&#x2028; LEVEL I: most uniform coordination of PDTG: British Columbia (Brit.Col.), with a single Provincial budget; earliest implementation of Provincial Community Oncology Program (since the mid-1970's); and a uniform start of Adj. SystTh (late 1970's); and of ScrM (late -1980's).&#x2028; LEVEL II: medium (Ontario).&#x2028; LEVEL III: least uniform (Atlantic Provinces)*.&#x2028; BrCa annual age-standardized mortality rates per 100,000/population were obtained from Statistics Canada for the years 1950-2004, and expressed relative to the year 1950 (the baseline).&#x2028; RESUTLS: The 1950 BrCa mortality rates were: 30.9 for Canada; 31.4 for BC; 30.7 Ontario; 26.1 for Atlantic Provinces*.&#x2028; &#x2028; CONCLUSIONS:&#x2028; While both Adj. SystTh and ScrM contribute towards recent BrCa mortality reduction, the British Columbia data indicate that the impact of Adj. SystTh antedates that of ScrM, at least by a decade.&#x2028; Our data support a correlation of BrCa mortality trends with the organization of cancer care: Effective implementation of PDTG (- i.e. incorporating early curative interventions into guidelines), will have a strong impact on mortality trends, particularly if executed&#x2028; a. ongoingly,&#x2028; b. uniformly, and&#x2028; c. across the whole population.&#x2028; Our data therefore indicate that early implementation of curative systemic therapy - or of any curative intervention - is essential, as their delay may prevent materialization of survival gains.

Citation Information: Cancer Res 2009;69(2 Suppl):Abstract nr 6083.

From expert-based to quantitative retrospective exposure assessment at a Soderberg aluminum smelter

OBJECTIVES

Expert judgement of exposure levels is often only poorly or moderately correlated with directly measured levels. For a follow-up of a historical cohort study at a Söderberg aluminum smelter we updated an expert-based semiquantitative job exposure matrix of coal tar pitch volatiles (CTPV) to quantitative estimates of CTPV and benzo(a)pyrene (BaP).

METHODS

Mixed effects models to predict exposure for potroom operation and maintenance jobs were constructed from personal CTPV and BaP measurements. Mean exposures of jobs in non-potroom locations were directly calculated when measurements were available. Exposure estimates for jobs/time periods with no measurements were based on proportion of time spent in exposed areas compared to jobs where exposure was modeled or measured. For pre-1977, the original expert exposure assignments were calibrated using the updated 1977 estimates.

RESULTS

The rate of change in exposure levels varied by time period and was accounted for in mixed models with a linear spline time trend. Other variables significant in the models were job, potroom group and season as fixed effects, and worker as a random effect. The models for potroom operations explained 45 and 27% of the variability in the CTPV and BaP measurements, respectively. The models for maintenance jobs explained 40 and 19% of the variability in the CTPV and BaP measurements, respectively. For 1977-2000 model estimates, direct calculation of means and extrapolation from modeled/measured exposures accounted for 57, 6 and 37% of the exposed person-years, respectively.

CONCLUSIONS

The above methodology maximized the use of exposure measurements and largely replaced the original expert-based estimates. Finer discrimination between exposure levels was possible with the updated exposure assessment. The new estimates are expected to reduce exposure misclassification and help better assess the exposure-response relationships.

Validation of a semi-quantitative job exposure matrix at a Söderberg aluminum smelter

OBJECTIVES

We tested the validity of a job exposure matrix (JEM) for coal tar pitch volatiles (CTPV) at a Söderberg aluminum smelter. The JEM had been developed by a committee of company hygienists and union representatives for an earlier study of cancer incidence and mortality. Our aim was to test the validity and reliability of the expert-based assignments.

METHODS

Personal CTPV exposure measurements (n = 1879) overlapped 11 yr of the JEM. The arithmetic mean was calculated for 35 job/time period combinations (35% of the exposed work history), categorized using the original exposure intervals, and compared with the expert-based assignments.

RESULTS

The expert-based and the measurement-based exposure assignments were only moderately correlated (Spearman's rho = 0.42; weighted kappa = 0.39, CI 0.10-0.69). Only 40% of the expert-based medium category assignments were correctly assigned, with better agreement in the low (84%) and high (100%) categories. Pot operation jobs exhibited better agreement (rho = 0.60) than the maintenance and pot shell repair jobs (rho = 0.25). The mid-point value of the medium category was overestimated by 0.3 mg/m(3).

CONCLUSIONS

The expert-based exposure assignments may be improved by better characterizing the transitions between exposure categories, by accounting for exposure differences between pot lines and by re-examining the category mid-point values used in calculating the cumulative exposure. Lack of historical exposure measurements often requires reliance on expert knowledge to assess exposure levels. Validating the experts' estimates against available exposure measurements may help to identify weaknesses in the exposure assessment where improvements may be possible, as was shown here.

Canadian male farm residents, pesticide safety handling practices, exposure to animals and non-Hodgkin's lymphoma (NHL)

BACKGROUND

A majority of published studies indicate that farmers have an elevated risk of developing non-Hodgkin's lymphoma (NHL) compared to other workers.

METHODS

We evaluated accidental exposure to pesticides, the use of personal protective equipment, and exposure to animals among male farm residents in a Canadian population-based, multi-centre, NHL-control questionnaire study.

RESULTS

In a multivariate model, the following variables had statistically significant adjusted odds ratios (OR) using 95% confidence intervals (95% CI) (a) higher risk: having more than 13 head of swine, raising bison, elk or ostriches, a personal history of cancer, > 4 and < or = 15 years of farm residence and occupational exposure to diesel fuel and exhaust; (b) lower risk: raising cattle and a personal history of measles.

CONCLUSIONS

Future multidisciplinary studies of NHL should include a comprehensive review of exposure to animals in sufficient detail to assess etiological mechanisms to explain the putative associations between exposure to farm animals and NHL.

Effect of resynchronization therapy stimulation site on the systolic function of heart failure patients

BACKGROUND

Cardiac resynchronization therapy (CRT) improves systolic function in heart failure patients with ventricular conduction delay by stimulating the left ventricle (LV) or both ventricles (biventricular, BV). Optimal LV site selection is of major clinical interest for CRT device implantation; however, the dependence of hemodynamics on LV stimulation site has not been established. Thus, the objective of this study was to compare the hemodynamic response to CRT for 2 LV coronary vein sites: the free wall and anterior wall. Methods and Results- A total of 30 patients (mean NYHA class, 2.7; mean QRS interval, 152 ms; mean PR interval, 194 ms) enrolled in the PATH-CHF-II trial were studied. CRT was administered with LV and BV stimulation in VDD mode at 4 AV delays. LV stimulation was at the lateral free wall or anterior wall, whereas right ventricular stimulation was fixed near the apex. LV+dP/dt(max) and aortic pulse pressure changes from baseline during CRT were compared for LV sites. Free wall sites with LV and BV stimulation yielded significantly larger LV+dP/dt(max) (14% versus 6%, P<0.001 for LV; 12% versus 5%, P<0.001 for BV) and pulse pressure (8% versus 4%, P<0.001 for LV; 9% versus 5%, P<0.001 for BV) compared with anterior sites. In one third of patients, CRT at free wall sites increased LV+dP/dt(max), whereas it decreased at anterior sites over most AV delays.

CONCLUSION

CRT with LV free wall stimulation produced significantly better LV systolic performance compared with anterior stimulation. Further studies are warranted to prove the clinical superiority of the LV free wall as a site for long-term CRT.

Impact of cardiac resynchronization therapy using hemodynamically optimized pacing on left ventricular remodeling in patients with congestive heart failure and ventricular conduction disturbances

OBJECTIVES

We sought to investigate the impact of six months of cardiac resynchronization therapy (CRT) on echocardiographic variables of left ventricular (LV) function.

BACKGROUND

Cardiac resynchronization therapy has recently been introduced as a new therapeutic modality in patients with advanced heart failure (HF) and conduction abnormalities. However, most studies have only investigated the early hemodynamic effects of CRT.

METHODS

Twenty-five patients (12 women and 13 men; 59.8 +/- 5.1 years old) with advanced HF caused by ischemic (n = 7) or idiopathic dilated cardiomyopathy (n = 18) and a prolonged QRS complex were analyzed. All patients underwent early hemodynamic testing with a randomized testing protocol; echocardiographic measurements were compared before implantation and after six months of CRT.

RESULTS

Left ventricular end-diastolic and end-systolic diameters (LVEDD and LVESD, respectively) were significantly reduced after six months (LVEDD from 71 +/- 10 to 68 +/- 11 mm, p = 0.027; LVESD from 63 +/- 11 to 58 +/- 11 mm, p = 0.007), as were LV end-diastolic and end-systolic volumes (LVEDV from 253 +/- 83 to 227 +/- 112 ml, p = 0.017; LVESV from 202 +/- 79 to 174 +/- 101 ml, p = 0.009). Ejection fraction was significantly increased (from 22 +/- 7% to 26 +/- 9%, p = 0.03). "Nonresponders," with regard to LV volume reduction, had significantly higher baseline LVEDV, compared with "responders" (351 +/- 52 vs. 234 +/- 74 ml, p = 0.018). Overall, there was only mild mitral regurgitation at baseline, with a minor reduction by semiquantitative analysis. The results of early hemodynamic testing did not predict the volume response.

CONCLUSIONS

Cardiac resynchronization therapy may lead to a reduction in LV volumes in patients with advanced HF and conduction disturbances. Volume nonresponders have significantly higher baseline LVEDV.

Non-Hodgkin's lymphoma and specific pesticide exposures in men: cross-Canada study of pesticides and health

Our objective in the study was to investigate the putative associations of specific pesticides with non-Hodgkin's Lymphoma [NHL; International Classification of Diseases, version 9 (ICD-9) 200, 202]. We conducted a Canadian multicenter population-based incident, case (n = 517)-control (n = 1506) study among men in a diversity of occupations using an initial postal questionnaire followed by a telephone interview for those reporting pesticide exposure of 10 h/year or more, and a 15% random sample of the remainder. Adjusted odds ratios (ORs) were computed using conditional logistic regression stratified by the matching variables of age and province of residence, and subsequently adjusted for statistically significant medical variables (history of measles, mumps, cancer, allergy desensitization treatment, and a positive history of cancer in first-degree relatives). We found that among major chemical classes of herbicides, the risk of NHL was statistically significantly increased by exposure to phenoxyherbicides [OR, 1.38; 95% confidence interval (CI), 1.06-1.81] and to dicamba (OR, 1.88; 95% CI, 1.32-2.68). Exposure to carbamate (OR, 1.92; 95% CI, 1.22-3.04) and to organophosphorus insecticides (OR, 1.73; 95% CI, 1.27-2.36), amide fungicides, and the fumigant carbon tetrachloride (OR, 2.42; 95% CI, 1.19-5.14) statistically significantly increased risk. Among individual compounds, in multivariate analyses, the risk of NHL was statistically significantly increased by exposure to the herbicides 2,4-dichlorophenoxyacetic acid (2,4-D; OR, 1.32; 95% CI, 1.01-1.73), mecoprop (OR, 2.33; 95% CI, 1.58-3.44), and dicamba (OR, 1.68; 95% CI, 1.00-2.81); to the insecticides malathion (OR, 1.83; 95% CI, 1.31-2.55), 1,1,1-trichloro-2,2-bis (4-chlorophenyl) ethane (DDT), carbaryl (OR, 2.11; 95% CI, 1.21-3.69), aldrin, and lindane; and to the fungicides captan and sulfur compounds. In additional multivariate models, which included exposure to other major chemical classes or individual pesticides, personal antecedent cancer, a history of cancer among first-degree relatives, and exposure to mixtures containing dicamba (OR, 1.96; 95% CI, 1.40-2.75) or to mecoprop (OR, 2.22; 95% CI, 1.49-3.29) and to aldrin (OR, 3.42; 95% CI, 1.18-9.95) were significant independent predictors of an increased risk for NHL, whereas a personal history of measles and of allergy desensitization treatments lowered the risk. We concluded that NHL was associated with specific pesticides after adjustment for other independent predictors.

HER-2/neu in breast cancer: interobserver variability and performance of immunohistochemistry with 4 antibodies compared with fluorescent in situ hybridization

The immunohistochemistry (IHC) performance of 4 anti-HER-2/neu antibodies was compared with fluorescent in situ hybridization (FISH) analysis of HER-2/neu gene expression in breast cancer patients considered for Herceptin (Trastuzumab) therapy. Interobserver variability in IHC interpretation was measured. Formalin-fixed tissue was received from 24 provincial hospital laboratories. The following anti-Her-2 antibodies were used: DAKO A0485 (polyclonal), Novacastra CB11 (monoclonal), Zymed TAB250 (monoclonal), and DAKO HercepTest (polyclonal). Additional sections were analyzed by FISH (Vysis). Three pathologists blinded to FISH results independently interpreted invasive tumor cell membranous staining on a scale of 0 to +3. The HER-2/neu gene was considered amplified when the FISH signal ratio of HER-2/CEP-17 was > or =2.0. Blocks from all hospitals and of all ages were suitable for IHC and FISH analysis. No interlaboratory analysis variability was noted. The interobserver agreement (kappa) for stain intensity for each antibody was good for 0 and +3 but poor for +1 and +2. Reasonable concordance between IHC and FISH was found with three of the four antibodies. TAB250 was the most sensitive antibody. For the three pathologists, the IHC sensitivities and specificities compared with FISH using 0/+1 as negative and +2/+3 as positive were as follows: A0485, 63-84/95-98; CB11, 63-66/97-98; TAB-250, 82-100/94-95; HercepTest, 59-77/91-93. The positive and negative predictive values varied by stain intensity. Stain scores of 0 and +3 were highly predictive of gene status. Stain scores of +1 and +2 were not sufficiently predictive to classify cases as amplified versus nonamplified. IHC is a reasonable first test to assess HER-2/neu status in patients with breast cancer. For most cases, DAKO A0485, TAB250, and HercepTest adequately predicted gene status. In cases with stain intensity of +1 or +2, the interobserver agreement is poor, and the predictive value is unsatisfactory for clinical use. Additional testing, preferably with FISH, is recommended.

Parity and carotid artery atherosclerosis in elderly women: The Rotterdam Study

BACKGROUND AND PURPOSE

It has been postulated that physiological changes in the cardiovascular system, lipids, and glucose metabolism during pregnancy may increase subsequent risk of cardiovascular disease. Examination of the association between parity and risk factors for atherosclerosis may contribute information regarding possible mechanisms.

METHODS

The relationship of parity with cardiovascular risk factors and the presence of carotid atherosclerosis was examined in the Rotterdam Study, a population-based study comprising 4878 women aged 55 years and older. Carotid atherosclerosis was assessed by ultrasonographic detection of plaques in the common carotid artery and bifurcation. Logistic regression models were used to compute odds ratios and 95% confidence intervals, adjusted for confounding factors.

RESULTS

Parity was inversely associated with high-density lipoprotein cholesterol, and alcohol intake. Parity was positively associated with body mass index, total/HDL cholesterol ratio, insulin resistance, age at menopause, and socioeconomic status. Relative to nulliparous women, parous women had 36% (9% to 71%) greater risk of carotid atherosclerosis, rising to 64% in women with >/=4 children (19% to 127%). Adjustment for known cardiovascular risk factors, including insulin resistance and current lipid levels, did not diminish the magnitude of this association.

CONCLUSIONS

Data demonstrated that there is a positive association between parity and risk of carotid artery plaques in elderly women and, further, that high parity is associated with lower HDL cholesterol levels and higher glucose/insulin ratios long after childbearing has ceased.

Simultaneous modelling of operative mortality and long-term survival after coronary artery bypass surgery

Typical analyses of lifetime data treat the time to death or failure as the response variable and use a variety of modelling strategies such as proportional hazards or fully parametric, to investigate the relationship between the response and covariates. In certain circumstances it may be more natural to view the distribution of the response variable as consisting of two or more parts since the survival curve appears segmented. This article addresses such a scenario and we propose a model for simultaneously investigating the effects of covariates over the two segments. The model is an analogue of that proposed by Lambert for zero-inflated Poisson regression. The application is central to the model development and is concerned with survival after coronary artery bypass surgery. Here operative mortality, defined as death within 30 days after surgery, and long-term mortality, are viewed as distinct outcomes. For the application considered, the survivor function displays much steeper descent during the first 30 days after surgery, that is, for operative mortality, than after this period. An investigation of the effects of covariates on operative and long-term mortality after coronary artery bypass surgery illustrates the usefulness of the proposed model.

Double trouble: impact of inappropriate use of asthma medication on the use of health care resources

BACKGROUND

There is considerable controversy about the regular use of short-acting beta-agonists for the treatment of asthma. Although case-control studies have suggested that excessive use of these drugs may worsen asthma control and increase the risk of fatal or near-fatal asthma, the controversy remains unresolved because of the confounding that exists among disease control, disease severity and the use of short-acting beta-agonists. Whatever the cause-and-effect relation between the use of short-acting beta-agonists and disease severity, we hypothesized that their excessive use, in conjunction with underuse of inhaled corticosteroids, would be a marker for poorly controlled asthma and excessive use of health care resources.

METHODS

To characterize the pattern of health services utilization among asthmatic patients taking various doses of inhaled beta-agonists and corticosteroids in British Columbia, we linked the relevant health administrative databases. All patients between 5 and 50 years of age for whom a prescription for a short-acting beta-agonist was filled in 1995 and whose prescription data were captured through the provincial drug plan were included in a retrospective analysis of prescriptions for asthma drugs, physician prescribing patterns and health services utilization. Patients' use of asthma medication was classified as appropriate (low doses of short-acting beta-agonist and high doses of inhaled corticosteroid) or inappropriate (high doses of short-acting beta-agonist and low doses of inhaled corticosteroid), and the 2 resulting groups were compared, by means of logistic, Poisson and gamma regression, for differences in prescribing patterns, physician visits and use of hospital resources.

RESULTS

A total of 23,986 patients were identified as having filled a prescription for a short-acting beta-agonist (for inhalation) in 1995. Of these, 3069 (12.8%) filled prescriptions for 9 or more canisters of beta-agonist, and of this group of high-dose beta-agonist users, 763 (24.9%) used no more than 100 micrograms/day of inhaled beclomethasone. On average, those with inappropriate use of beta-agonists visited significantly more physicians for their prescriptions (1.8 v. 1.4), and each of these physicians on average wrote significantly more prescriptions for asthma medications per patient than the physicians who prescribed to appropriate users (5.2 v. 2.5 prescriptions). Patients with inappropriate use were more likely to be admitted to hospital (adjusted relative risk [RR] 1.68, 95% confidence interval [CI] 1.25-2.26), were admitted to hospital more frequently (adjusted RR 1.81, 95% CI 1.41-2.32) and were more likely to require emergency admission (adjusted RR 1.93, 95% CI 1.35-2.77).

INTERPRETATION

Despite the widespread distribution of guidelines for asthma pharmacotherapy, inappropriate use of asthma medications persists (specifically excessive use of inhaled short-acting beta-agonists combined with underuse of inhaled corticosteroids). Not only are patients who use medication inappropriately at higher risk for fatal or near-fatal asthma attacks, but, as shown in this study, they use significantly more health care resources than patients with appropriate medication use.

Value of ST elevation in lead III greater than lead II in inferior wall acute myocardial infarction for predicting in-hospital mortality and diagnosing right ventricular infarction

ST elevation in lead III > II has a higher sensitivity than lead V4R in diagnosing right ventricular myocardial infarction. Lead III > II is also predictive of in-hospital mortality.

Underutilization of acute care settings in a tertiary care hospital

OBJECTIVE

To estimate underutilization of acute care settings in a tertiary care hospital.

DESIGN

A retrospective and concurrent cohort study using chart reviews and the Intensity of service, Severity of illness, Discharge screen for Acute Care (ISD-AC(R)) tool to measure appropriateness of acute care for patients who were receiving care in a less acute setting, as an indicator of underutilization.

SETTING

A 450-bed tertiary care teaching hospital.

STUDY PARTICIPANTS

Patients discharged from the emergency department, patients discharged from acute care inpatient units and patients in acute, non-critical care settings.

INTERVENTIONS

None.

MAIN OUTCOME MEASURES

The percentage of patients discharged from the emergency department who did not meet the criteria for acute care discharge screens; the percentage of patients discharged from an acute care inpatient unit who did not meet the criteria for discharge screens; and the percentage of patients who were in acute, non-critical care beds and who met the criteria for critical care.

RESULTS

It was found that six out of 168 patients [3.57%; 95% confidence interval (CI), 1.32-7.61%] did not meet the discharge screens at the time of discharge from the emergency department. Four out of 156 patients (2.56%; 95% CI, 0.70-6.43%) did not meet the discharge screens at the time of discharge from an acute care inpatient service and two out of 156 acute care patients (1.33%; 95% CI, 0.02-4.73%) who were in non-critical care beds met the criteria for critical care.

CONCLUSION

These findings of underutilization may help to quantitate an unmet need in health care.

Cardiac resynchronization for heart failure: present status

Ventricular dysfunction is a hallmark of heart failure, and is often linked to ventricular dilatation and ventricular conduction delays. Recent studies have demonstrated that systolic function can be improved in patients with left bundle branch block by pre-exciting the site of late activation, usually the left ventricular free wall. Furthermore, it has been recently reported that this improvement is associated with a decrease in myocardial oxygen consumption. We hypothesize that the pre-excitation of the region covered by the blocked bundle acts as an "electrical bypass," resynchronizing the contraction of the septum and the left ventricular free wall. In addition, optimization of the electronic atrioventricular delay allows the simultaneous resynchronization of the atrioventricular contractions, and minimization of diastolic mitral regurgitation. Systolic mitral regurgitation may also be reduced by removing the geometric distortion introduced by the left bundle branch block. The recently reported positive outcome of the PATH-CHF I controlled trial reinforces that the positive acute and chronic results that have been reported up to now may translate into long-term clinical benefit for patients with heart failure and conduction defects. Larger studies are needed to confirm these initial results and to establish the impact of this new therapeutic modality on morbidity and mortality. (c)2000 by CHF, Inc.

Early discharge of patients with presumed opioid overdose: development of a clinical prediction rule

OBJECTIVE

To develop a clinical prediction rule to identify patients who can be safely discharged one hour after the administration of naloxone for presumed opioid overdose.

METHODS

Patients who received naloxone for known or presumed opioid overdose were formally evaluated one hour later for multiple potential predictor variables. Patients were classified into two groups: those with adverse events within 24 hours and those without. Using classification and regression tree methodology, a decision rule was developed to predict safe discharge.

RESULTS

Clinical findings from 573 patients allowed us to develop a clinical prediction rule with a sensitivity of 99% (95% CI = 96% to 100%) and a specificity of 40% (95% CI = 36% to 45%). Patients with presumed opioid overdose can be safely discharged one hour after naloxone administration if they: 1) can mobilize as usual; 2) have oxygen saturation on room air of >92%; 3) have a respiratory rate >10 breaths/min and <20 breaths/min; 4) have a temperature of >35.0 degrees C and <37.5 degrees C; 5) have a heart rate >50 beats/min and <100 beats/min; and 6) have a Glasgow Coma Scale score of 15.

CONCLUSIONS

This prediction rule for safe early discharge of patients with presumed opioid overdose performs well in this derivation set but requires validation followed by confirmation of safe implementation.

Volume expansion using pentastarch does not change gastric-arterial CO2 gradient or gastric intramucosal pH in patients who have sepsis syndrome

OBJECTIVE

In hypovolemic patients with sepsis syndrome, to determine the effects of colloid volume infusion using 10% pentastarch on abnormal gastric tonometer measurements (gastric intramucosal CO2 tension, gastric intramucosal-arterial PCO2 gradient, and gastric intramucosal pH [pHi]) and on cardiac index, global oxygen delivery, and hemoglobin.

DESIGN

Prospective prepost intervention study.

SETTING

Tertiary care, university-affiliated 15-bed general systems intensive care unit.

PATIENTS

Patients were studied who had sepsis syndrome, who had pulmonary arterial catheters in place, who were hypovolemic (pulmonary arterial occlusion pressure [PAOP] <15 mm Hg), and who had a gastric arterial PCO2 gradient >10 mm Hg.

INTERVENTIONS

Baseline measurements of gastric intramucosal CO2 tension, gastric intramucosal-arterial PCO2 gradient, and pHi, as well as arterial lactate, pulmonary arterial occlusion, central venous and systemic arterial pressures, thermodilution cardiac output, and temperature. Boluses of 500 mL pentastarch were administered to a total of 1,000 mL or until PAOP was >18 mm Hg. Measurements were repeated at 30 mins and 120 mins postinfusion of pentastarch.

MAIN RESULTS

Volume infusion using pentastarch did not change gastric PCO2, gastric-arterial PCO2 gradient, or pHi. Volume expansion with pentastarch significantly increased cardiac index, global oxygen delivery, and PAOP. Administration of pentastarch decreased hemoglobin and arterial lactate at 30 mins but not at 120 mins.

CONCLUSIONS

Volume expansion using a colloidal solution of 10% pentastarch does not change abnormal intramucosal CO2 tension, gastric-arterial PCO2 gradient, or pHi in critically ill hypovolemic patients who have sepsis syndrome despite increasing cardiac index, oxygen delivery, and pulmonary artery occlusion pressure.

Polymorphisms in the IL4, IL4RA, and FCERIB genes and asthma severity

BACKGROUND

Genetic polymorphisms have been associated with asthma and asthma severity.

OBJECTIVE

We sought to determine whether 3 polymorphisms were associated with severe asthma indicated either by the occurrence of a fatal (or near-fatal) asthma attack or by severe airflow obstruction.

METHODS

We obtained DNA and clinical data from asthmatic subjects who either died or nearly died during an asthma attack and from a group of subjects with mild-to-moderate asthma who had never experienced a fatal or near-fatal asthma episode. These groups were compared with a group of nonatopic nonasthmatic control subjects. The level of airflow obstruction (FEV(1) percent predicted) in the subjects with mild-to-moderate asthma was used as an additional measure of disease severity. The subjects were genotyped for the IL4*C-589T promoter polymorphism and the IL4RA*Q576R and the FCERIB*E237G amino acid substitutions.

RESULTS

The results showed that the FCERIB*E237G and IL4RA*Q576R polymorphisms were not associated with fatal or near-fatal asthma. However, the IL4*-589T allele was significantly increased in the subjects with fatal or near-fatal asthma compared with nonasthmatic subjects (odds ratio [OR], 1.8; P =.02) and subjects with mild-to-moderate asthma (OR, 1.9; P =.02). There was no interaction between the IL4*-589T and IL4RA*576R alleles. Of the 3 polymorphisms, only the IL4RA*576R allele was associated with severe airflow obstruction (OR, 8.2; P =.01).

CONCLUSION

These data suggest that the IL4*-589T allele is a risk factor for life-threatening asthma and that the IL4RA*576R allele is a risk factor for a low level of lung function in asthmatic subjects.

Cardiac pacing in heart failure patients with left bundle branch block: impact of pacing site for optimizing left ventricular resynchronization

BACKGROUND

Acute left ventricular pacing has been associated with hemodynamic improvement in patients with congestive heart failure and wide QRS complex. We hypothesized that pacing two left ventricular sites simultaneously would produce faster activation and better systolic function than single-site pacing.

METHODS

We selected 14 heart failure patients (NYHA functional class III or IV) in normal sinus rhythm with left bundle branch block and QRS > 150 ms. An 8F dual micromanometer catheter was placed in the aorta for measuring +dP/dt (mmHg/s), aortic pulse pressure (mmHg), and end-diastolic pressure (mmHg). Pacing leads were positioned via coronary veins at the posterior base and lateral wall. Patients were acutely paced VDD at the posterior base, lateral wall, and both sites (dual-site) with 5 atrioventricular delays (from 8 ms to PR -30 ms). Pacing sequences were executed in randomized order using a custom external computer (FlexStim, Guidant CRM).

RESULTS

Dual-site pacing increased peak +dP/dt significantly more than posterior base and lateral wall pacing. Dual-site and posterior base pacing raised aortic pulse pressure significantly more than lateral wall pacing. Dual-site pacing shortened QRS duration by 22 %, whereas posterior base and lateral wall pacing increased it by 2 and 12%, respectively (p = 0.006).

CONCLUSIONS

In heart failure patients with left bundle branch block, dual-site pacing improves systolic function more than single-site stimulation. Improved ventricular activation synchrony, expressed by paced QRS narrowing, may account for the additional benefit of dual- vs single-site pacing in enhancing contractility. This novel approach deserves consideration for future heart failure pacing studies.