Recall bias in case-control studies: an empirical analysis and theoretical framework

Psychological impact of life events in systemic lupus erythematosus patients - Differences between flares and remission

BACKGROUND

Stress has been linked to worsening symptoms and increased disease activity in patients with Systemic lupus erythematosus (SLE). Life-events are individual stress points, and there is conflicting evidence regarding their role in SLE activity and disease perception.

METHODS

Adult SLE patients were recruited for the study. Clinical and laboratory features of SLE were recorded, and previous diagnosis of anxiety or depression were retrieved from patients' electronic charts. Flares were defined by the Systemic Lupus Erythematosus Disease Activity (SLEDAI) flare Index, and flares during the previous year were documented. During a routine visit, they completed validated Portuguese translations of the 10-item Perceived Stress Scale (PSS-10), Hospital Anxiety and Depression Scale (HADS) and Life Experience Survey (LES) for the previous year.

RESULTS

A total of 47 female SLE patients were recruited. Ten patients (21.3%) had experienced recent flares. Patients with recent flares reported fewer life events, with lower positive, negative, and total weightings sums compared to those without recent flares. Although 42.2% of patients perceived pathological levels of stress in the previous month, 48.9% had anxiety symptoms, and 34% were at high risk for an anxiety disorder, these psychometric measures did not differ significantly between the recent flare and no-flare groups.

CONCLUSIONS

There is a high prevalence of pathological levels of stress among SLE patients. SLE patients with recent flares report less psychological impact from life events, both positive and negative, independent of other psychological or pharmacological factors.

Dosis‐Wirkungs‐Beziehung zwischen Alkoholkonsum und Psoriasis: Systematische Übersicht und Metaanalyse

The association between psoriasis and alcohol consumption has been inconsistent across various studies. However, to the best of our knowledge, no dose-response meta-analysis has been performed to date. This study aims to investigate the association between alcohol consumption and psoriasis. The search was performed on July 27, 2021, using Embase and MEDLINE. The restricted cubic spline analysis was used to perform a dose-response analysis. We identified 3,904 studies, of which 48 studies with 1,702,847 individuals across 24 countries were included. Alcohol consumption was positively associated with psoriasis (odds ratio [OR], 1.47; 95% confidence interval [CI], 1.27-1.70). In addition, a significantly increased OR for psoriasis was observed in males (OR, 1.84; 95% CI, 1.13-3.01) but not in females (OR, 1.22; 95% CI, 0.97-1.54). Based on eight studies, including three cohort and five case-control studies, the analysis revealed that with each additional gram of daily alcohol intake, the OR for psoriasis increased by 4%. We found a positive association between alcohol consumption and psoriasis. The association is more prominent in the group drinking more than 45 g of alcohol per day (3.2 alcoholic drink equivalent).

Dose-response analysis between alcohol consumption and psoriasis: A systematic review and meta-analysis

The association between psoriasis and alcohol consumption has been inconsistent across various studies. However, to the best of our knowledge, no dose-response meta-analysis has been performed to date. This study aims to investigate the association between alcohol consumption and psoriasis. The search was performed on July 27, 2021, using Embase and MEDLINE. The restricted cubic spline analysis was used to perform a dose-response analysis. We identified 3,904 studies, of which 48 studies with 1,702,847 individuals across 24 countries were included. Alcohol consumption was positively associated with psoriasis (odds ratio [OR], 1.47; 95% confidence interval [CI], 1.27-1.70). In addition, a significantly increased OR for psoriasis was observed in males (OR, 1.84; 95% CI, 1.13-3.01) but not in females (OR, 1.22; 95% CI, 0.97-1.54). Based on eight studies, including three cohort and five case-control studies, the analysis revealed that with each additional gram of daily alcohol intake, the OR for psoriasis increased by 4%. We found a positive association between alcohol consumption and psoriasis. The association is more prominent in the group drinking more than 45 g of alcohol per day (3.2 alcoholic drink equivalent).

Subjective Quality of Life of Women in the Perinatal Period: A Post Covid-19 Pandemic Exploration in North Macedonia

Subjective quality of life could be considered one of the indicators of health behavior and wellbeing of women in the perinatal period. Accordingly, the aim of this paper was to examine how women in perinatal period perceive quality of life in various domains. Its relationship to age, number of pregnancies, course of pregnancies, and method of delivery and experience with Covid-19 pandemic was investigated, as well. Our sample consisted of 366 pregnant women in any period of pregnancy who came in for regular outpatient examinations and control, those who were hospitalized due to pathological pregnancy or due to the need for intensive care, as well as women in their postnatal period, one year after delivery, who were seeking professional advice from a gynecologist. The majority were aged 20 to 30 years (53.8%). The findings showed that assessed domains of subjective quality of life were related to a variety of experiences with the Covid-19 pandemic. The results are presented and discussed in detail. Implications and limitations are given, as well.

The Burden of Proof studies: assessing the evidence of risk

Exposure to risks throughout life results in a wide variety of outcomes. Objectively judging the relative impact of these risks on personal and population health is fundamental to individual survival and societal prosperity. Existing mechanisms to quantify and rank the magnitude of these myriad effects and the uncertainty in their estimation are largely subjective, leaving room for interpretation that can fuel academic controversy and add to confusion when communicating risk. We present a new suite of meta-analyses-termed the Burden of Proof studies-designed specifically to help evaluate these methodological issues objectively and quantitatively. Through this data-driven approach that complements existing systems, including GRADE and Cochrane Reviews, we aim to aggregate evidence across multiple studies and enable a quantitative comparison of risk-outcome pairs. We introduce the burden of proof risk function (BPRF), which estimates the level of risk closest to the null hypothesis that is consistent with available data. Here we illustrate the BPRF methodology for the evaluation of four exemplar risk-outcome pairs: smoking and lung cancer, systolic blood pressure and ischemic heart disease, vegetable consumption and ischemic heart disease, and unprocessed red meat consumption and ischemic heart disease. The strength of evidence for each relationship is assessed by computing and summarizing the BPRF, and then translating the summary to a simple star rating. The Burden of Proof methodology provides a consistent way to understand, evaluate and summarize evidence of risk across different risk-outcome pairs, and informs risk analysis conducted as part of the Global Burden of Diseases, Injuries, and Risk Factors Study.

Estimating the global health impact of gender-based violence and violence against children: a systematic review and meta-analysis protocol

INTRODUCTION

Exposure to gender-based violence (GBV) and violence against children (VAC) can result in substantial morbidity and mortality. Previous reviews of health outcomes associated with GBV and VAC have focused on limited definitions of exposure to violence (ie, intimate partner violence) and often investigate associations only with predefined health outcomes. In this protocol, we describe a systematic review and meta-analysis for a comprehensive assessment of the impact of violence exposure on health outcomes and health-related risk factors across the life-course.

METHODS AND ANALYSIS

Electronic databases (PubMed, Embase, CINAHL, PsycINFO, Global Index Medicus, Cochrane and Web of Science Core Collection) will be searched from 1 January 1970 to 30 September 2021 and searches updated to the current date prior to final preparation of results. Reviewers will first screen titles and abstracts, and eligible articles will then be full-text screened and accepted should they meet all inclusion criteria. Data will be extracted using a standardised form with fields to capture study characteristics and estimates of association between violence exposure and health outcomes. Individual study quality will be assessed via six risk of bias criteria. For exposure-outcome pairs with sufficient data, evidence will be synthesised via a meta-regression-Bayesian, regularised, trimmed model and confidence in the cumulative evidence assessed via the burden of proof risk function. Where possible, variations in associations by subgroup, that is, age, sex or gender, will be explored.

ETHICS AND DISSEMINATION

Formal ethical approval is not required. Findings from this review will be used to inform improved estimation of GBV and VAC within the Global Burden of Disease Study. The review has been undertaken in conjunction with the Lancet Commission on GBV and the Maltreatment of Young People with the aim of providing new data insights for a report on the global response to violence.

PROSPERO REGISTRATION NUMBER

CRD42022299831.

Age of First Exposure to Contact and Collision Sports and Later in Life Brain Health: A Narrative Review

A controversial theory proposes that playing tackle football before the age of 12 causes later in life brain health problems. This theory arose from a small study of 42 retired National Football League (NFL) players, which reported that those who started playing tackle football at a younger age performed worse on selected neuropsychological tests and a word reading test. The authors concluded that these differences were likely due to greater exposure to repetitive neurotrauma during a developmentally sensitive maturational period in their lives. Several subsequent studies of current high school and collegiate contact/collision sports athletes, and former high school, collegiate, and professional tackle football players have not replicated these findings. This narrative review aims to (i) discuss the fundamental concepts, issues, and controversies surrounding existing research on age of first exposure (AFE) to contact/collision sport, and (ii) provide a balanced interpretation, including risk of bias assessment findings, of this body of evidence. Among 21 studies, 11 studies examined former athletes, 8 studies examined current athletes, and 2 studies examined both former and current athletes. Although the literature on whether younger AFE to tackle football is associated with later in life cognitive, neurobehavioral, or mental health problems in former NFL players is mixed, the largest study of retired NFL players (N = 3,506) suggested there was not a significant association between earlier AFE to organized tackle football and worse subjectively experienced cognitive functioning, depression, or anxiety. Furthermore, no published studies of current athletes show a significant association between playing tackle football (or other contact/collision sports) before the age of 12 and cognitive, neurobehavioral, or mental health problems. It is important to note that all studies were judged to be at high overall risk of bias, indicating that more methodologically rigorous research is needed to understand whether there is an association between AFE to contact/collision sports and later in life brain health. The accumulated research to date suggests that earlier AFE to contact/collision sports is not associated with worse cognitive functioning or mental health in (i) current high school athletes, (ii) current collegiate athletes, or (iii) middle-aged men who played high school football. The literature on former NFL players is mixed and does not, at present, clearly support the theory that exposure to tackle football before age 12 is associated with later in life cognitive impairment or mental health problems.

The American Society of Pain and Neuroscience (ASPN) Practical Guidelines to Study Design and Scientific Manuscript Preparation in Neuromodulation

Background

Healthcare clinical and even policy decisions are progressively made based on research-based evidence. The process by which the appropriate trials are developed and well-written manuscripts by means of evidence-based medicine recommendations has resulted in unprecedented necessity in evidence-based medicine in neuromodulation.

Methods

The essential considerations in the planning of neuromodulation research are discussed in the light of available scientific literature as well as the authors’ scientific expertise regarding research study design and scientific manuscript preparation.

Conclusion

This article should enable the reader to understand how to appropriately design a clinical research study and prepare scientific manuscripts. The high-quality and well-designed studies, when performed and reported effectively, support evidence-based medicine and foster improved patient outcomes.

Adherence to Alternative Healthy Eating Index (AHEI-2010) is not associated with risk of stroke in Iranian adults: A case-control study

Background: Stroke is a major global health problem that contributes to a significant burden of morbidity and mortality. The association of several foods and nutrients with stroke has been well-established. However, the effect of the whole diet on stroke is poorly understood. In this work, we aimed to examine the association between the quality of whole diet, as measured using Alternate Healthy Eating Index-2010 (AHEI-2010), and risk of stroke in Iranian adults. Methods: In this hospital-based case-control study, 193 stroke patients (diagnosed based on clinical and brain CT findings) and 193 controls with no history of cerebrovascular diseases or neurologic disorders were included. The participants' dietary intakes were examined using a validated 168-item semi-quantitative food frequency questionnaire. AHEI-2010 was constructed based on earlier studies. Participants were classified according to tertiles of AHEI-2010 scores and multivariate logistic regression was used to evaluate the association between whole diet quality and risk of stroke. Results: Individuals with greater adherence to AHEI-2010 had a higher intake of fruits, vegetables, nuts and legumes, whole grains and carbohydrate, and a lower intake of trans-fatty acids, sugar-sweetened beverages, total energy and fat (P < 0.05). After adjusting for potential confounders, adherence to AHEI-2010 was not significantly associated with a reduced risk of stroke (OR: 0.92; 95% CI: 0.56-1.51). Conclusion: We found that adherence to AHEI-2010 was not associated with risk of stroke in Iranian adults. Further prospective studies are warranted to validate this finding and clarify the relationship between whole diet and stroke.

The association between coffee consumption and bladder cancer in the bladder cancer epidemiology and nutritional determinants (BLEND) international pooled study

Background

Inconsistent results for coffee consumption and bladder cancer (BC) risk have been shown in epidemiological studies. This research aims to increase the understanding of the association between coffee consumption and BC risk by bringing together worldwide case–control studies on this topic.

Methods

Data were collected from 13 case–control comprising of 5,911 cases and 16,172 controls. Pooled multivariate odds ratios (ORs), with corresponding 95% confidence intervals (CIs), were obtained using multilevel logistic regression models. Furthermore, linear dose–response relationships were examined using fractional polynomial models.

Results

No association of BC risk was observed with coffee consumption among smokers. However, after adjustment for age, gender, and smoking, the risk was significantly increased for never smokers (ever vs. never coffee consumers: OR_model2 1.30, 95% CI 1.06–1.59; heavy (> 4 cups/day) coffee consumers vs. never coffee consumers: OR_model2 1.52, 95% CI 1.18–1.97, p trend = 0.23). In addition, dose–response analyses, in both the overall population and among never smokers, also showed a significant increased BC risk for coffee consumption of more than four cups per day. Among smokers, a significant increased BC risk was shown only after consumption of more than six cups per day.

Conclusion

This research suggests that positive associations between coffee consumption and BC among never smokers but not smokers.

Tea and coffee consumption in relation to glioma: a case-control study

PURPOSE

Data on the link between tea and coffee consumption and risk of glioma are controversial. We aimed to examine the association between tea and coffee consumption and glioma in Iranian adults.

METHODS

In this hospital-based case-control study, we enrolled 128 pathologically confirmed new cases of glioma and 256 age- and sex-matched controls. Dietary intakes of study participants including tea and coffee consumption was assessed using the validated Block-format 123-item semi-quantitative FFQ. Participants were categorized based on tertiles of tea and coffee consumption. Data on potential confounders were also collected through the use of pre-tested questionnaire.

RESULTS

Individuals with the greatest tea consumption were less likely to have glioma compared with those with the lowest consumption (0.36; 0.20-0.68). This inverse association was not changed after controlling for energy intake. The association remained statistically significant even after taking other potential confounders, including dietary intakes of red and processed meats, legumes and nuts, fruits, salt and mutual effects of tea and coffee consumption, into account (0.33; 0.13-0.86). Additional adjustments for BMI did not alter the association. After controlling for potential confounders, including dietary intakes and BMI, coffee consumption was inversely associated with odds of glioma; such that individuals in the top category of coffee consumption were 91% less likely to have glioma compared with those in the bottom category (0.09; 0.03-0.24). Considering coffee and tea intake combined, those in the highest tertile were 65% less likely to have glioma compared with those in the lowest tertile (0.35; 0.15-0.83).

CONCLUSION

We found an inverse association between tea and coffee consumption and odds of glioma, even after controlling for a wide range of confounders.

High-heeled shoes and musculoskeletal injuries: a narrative systematic review

OBJECTIVES

To conduct the first systematic review from an epidemiological perspective regarding the association between high-heeled shoe wear and hallux valgus, musculoskeletal pain, osteoarthritis (OA) and both first-party and second-party injury in human participants without prior musculoskeletal conditions.

SETTING

A systematic review of international peer-reviewed scientific literature across seven major languages.

DATA SOURCES

Searches were conducted on seven major bibliographic databases in July 2015 to initially identify all scholarly articles on high-heeled shoes. Supplementary manual searches were conducted. Titles, abstracts and full-text articles were sequentially screened to identify all articles assessing epidemiological evidence regarding the association between high-heeled shoe wear and hallux valgus, musculoskeletal pain, OA and both first-party and second-party injury in human participants without prior musculoskeletal conditions. Standardised data extraction and quality assessment (Threats to Validity tool) were conducted.

PRIMARY AND SECONDARY OUTCOME MEASURES

Musculoskeletal pain or OA as assessed by clinical diagnosis or clinical assessment tool. First-party or second-party injury.

RESULTS

644 unique records were identified, 56 full-text articles were screened and 18 studies included in the review. Four studies assessed the relationship with hallux valgus and three found a significant association. Two studies assessed the association with OA and neither found a significant association. Five studies assessed the association with musculoskeletal pain and three found a significant association. Eight studies assessed first-party injury and seven found evidence of a significant injury toll associated with high-heeled shoes. One study provided data on second-party injury and the injury toll was low.

CONCLUSIONS

High-heeled shoes were shown to be associated with hallux valgus, musculoskeletal pain and first-party injury. No conclusive evidence regarding OA and second-party injury was found. Societal and clinical relevance of these findings is discussed. Concern is expressed about the expectation to wear high-heeled shoes in some work and social situations and access by children.

Environmental and gene-environment interactions and risk of rheumatoid arthritis

Multiple environmental factors including hormones, dietary factors, infections, and exposure to tobacco smoke, as well as gene-environment interactions, have been associated with increased risk for rheumatoid arthritis (RA). The growing understanding of the prolonged period before the first onset of symptoms of RA suggests that these environmental and genetic factors are likely acting to drive the development of RA-related autoimmunity long before the appearance of the first joint symptoms and clinical findings that are characteristic of RA. This article reviews these factors and interactions, especially those that have been investigated in a prospective fashion before the symptomatic onset of RA.

Investigating helmet promotion for cyclists: results from a randomised study with observation of behaviour, using a semi-automatic video system

Introduction

Half of fatal injuries among bicyclists are head injuries. While helmet use is likely to provide protection, their use often remains rare. We assessed the influence of strategies for promotion of helmet use with direct observation of behaviour by a semi-automatic video system.

Methods

We performed a single-centre randomised controlled study, with 4 balanced randomisation groups. Participants were non-helmet users, aged 18–75 years, recruited at a loan facility in the city of Bordeaux, France. After completing a questionnaire investigating their attitudes towards road safety and helmet use, participants were randomly assigned to three groups with the provision of “helmet only”, “helmet and information” or “information only”, and to a fourth control group. Bikes were labelled with a colour code designed to enable observation of helmet use by participants while cycling, using a 7-spot semi-automatic video system located in the city. A total of 1557 participants were included in the study.

Results

Between October 15th 2009 and September 28th 2010, 2621 cyclists' movements, made by 587 participants, were captured by the video system. Participants seen at least once with a helmet amounted to 6.6% of all observed participants, with higher rates in the two groups that received a helmet at baseline. The likelihood of observed helmet use was significantly increased among participants of the “helmet only” group (OR = 7.73 [2.09–28.5]) and this impact faded within six months following the intervention. No effect of information delivery was found.

Conclusion

Providing a helmet may be of value, but will not be sufficient to achieve high rates of helmet wearing among adult cyclists. Integrated and repeated prevention programmes will be needed, including free provision of helmets, but also information on the protective effect of helmets and strategies to increase peer and parental pressure.

The use of a new virtual cohort study design to investigate an outbreak of E. coli O157 linked to a supermarket delicatessen

In outbreaks of foodborne disease associated with retail outlets, the outlet often closes as a precaution before the specific food vehicle has been identified. Suspect food vehicles may be named as part of general control measures. A conventional case-control study cannot be performed because both cases and potential controls are likely to be aware of the hypothesis and therefore potentially biased. Modern sales recording systems in many food retail outlets may provide a basis for constructing a virtual cohort and allow a statistical inference to be made about various possible vehicles of infection. In 2007, an outbreak of E. coli O157 infection in Paisley, Scotland, was linked to cooked meat from a supermarket delicatessen using descriptive epidemiology. Construction of a virtual cohort allowed a relative risk and confidence interval to be estimated which supported the hypothesis of cooked beef topside being the vehicle of infection. This novel method could be valuable in the investigation of future outbreaks.

Invited commentary: Recall bias in melanoma -- much ado about almost nothing?

Recall bias has been given considerable attention in textbooks and methodological research because of its potential to jeopardize the validity of epidemiologic results. Case-control studies on self-reported ultraviolet radiation exposure as a risk factor for melanoma have been described as especially prone to the deleterious effect of recall bias because of the growing public awareness about these risks. Using an ideal test-retest design in a large nested case-control study, Parr et al. (Am J Epidemiol. 2009;169(3):257-266) examined to what extent recall bias in melanoma risk factors is actually identifiable and which consequences its presence has on effect estimates of these risk factors. They found only minor indications of recall bias, showing an inconsistent overall pattern and a quite negligible effect on risk estimates. Recall bias was not observed in those exposures where it was most expected (solarium use and other ultraviolet radiation-related exposures). Their findings cannot be used as an argument that future case-control studies in melanoma epidemiology should be avoided because of the biasing effect of recall bias.

Maternal medication use and the risk of brain tumors in the offspring: the SEARCH international case-control study

N-nitroso compounds (NOC) have been associated with carcinogenesis in a wide range of species, including humans. There is strong experimental data showing that nitrosamides (R(1)NNO.COR(2)), a type of NOC, are potent neuro-carcinogens when administered transplacentally. Some medications are a concentrated source of amides or amines, which in the presence of nitrites under normal acidic conditions of the stomach can form NOC. Therefore, these compounds, when ingested by women during pregnancy, may be important risk factors for tumors of the central nervous system in the offspring. The aim of the present study was to test the association between maternal use of medications that contain nitrosatable amines or amides and risk of primary childhood brain tumors (CBT). A case-control study was conducted, which included 1,218 cases and 2,223 population controls, recruited from 9 centers across North America, Europe and Australia. Analysis was conducted for all participants combined, by tumor type (astroglial, primitive neuroectodermal tumors and other glioma), and by age at diagnosis (< or =5 years; >5 years). There were no significant associations between maternal intake of medication containing nitrosatable amines or amides and CBT, for all participants combined and after stratification by age at diagnosis and histological subtype. This is the largest case-control study of CBT and maternal medications to date. Our data provide little support for an association between maternal use of medications that may form NOC and subsequent development of CBT in the offspring.

Genotype and early development in Rett syndrome: the value of international data

BACKGROUND

Rett syndrome is a neurodevelopmental disorder mostly affecting females and caused by mutations in the MECP2 gene. Originally the syndrome was characterised as having a normal prenatal and perinatal period with later regression. Previous work has speculated that the girl with Rett syndrome may not be normal at birth.

AIMS

to examine whether early development between birth and ten months varies by genotype in Rett syndrome.

METHODS

cases were sourced from two databases, the Australian Rett Syndrome Database (est. 1993) and the newly formed InterRett - IRSA Rett Phenotype Database. Data available on 320 cases included information provided by parents on perinatal problems, early developmental behaviour and mobility. Problem scores, mobility scores and a total composite score for each mutation were generated and compared.

RESULTS

overall, 58% of respondents noted unusual behaviour during the first six months and 70.6% from the period between 6 and 10 months of life. Statistically significant differences were detected between some of the common mutations. Infants with R294X (P=0.05) and R133C (P=0.03) were less likely than those with R255X to have problems in the perinatal period. The most severe profile overall for early development was associated with mutations R255X and R270X.

CONCLUSION

This is the largest study to date examining the effects of individual mutations in Rett syndrome. With the ongoing case ascertainment and expansion of InterRett, sample size will increase rapidly and provide improved statistical power for future analyses. Results from this study will contribute to understanding the mechanism of early development in Rett syndrome and determining if and at which time(s) early intervention might be feasible.

Using the ecology model to describe the impact of asthma on patterns of health care

BACKGROUND

Asthma changes both the volume and patterns of healthcare of affected people. Most studies of asthma health care utilization have been done in selected insured populations or in a single site such as the emergency department. Asthma is an ambulatory sensitive care condition making it important to understand the relationship between care in all sites across the health service spectrum. Asthma is also more common in people with fewer economic resources making it important to include people across all types of insurance and no insurance categories. The ecology of medical care model may provide a useful framework to describe the use of health services in people with asthma compared to those without asthma and identify subgroups with apparent gaps in care.

METHODS

This is a case-control study using the 1999 U.S. Medical Expenditure Panel Survey. Cases are school-aged children (6 to 17 years) and young adults (18 to 44 years) with self-reported asthma. Controls are from the same age groups who have no self-reported asthma. Descriptive analyses and risk ratios are placed within the ecology of medical care model and used to describe and compare the healthcare contact of cases and controls across multiple settings.

RESULTS

In 1999, the presence of asthma significantly increased the likelihood of an ambulatory care visit by 20 to 30% and more than doubled the likelihood of making one or more visits to the emergency department (ED). Yet, 18.8% of children and 14.5% of adults with asthma (over a million Americans) had no ambulatory care visits for asthma. About one in 20 to 35 people with asthma (5.2% of children and 3.6% of adults) were seen in the ED or hospital but had no prior or follow-up ambulatory care visits. These Americans were more likely to be uninsured, have no usual source of care and live in metropolitan areas.

CONCLUSION

The ecology model confirmed that having asthma changes the likelihood and pattern of care for Americans. More importantly, the ecology model identified a subgroup with asthma who sought only emergent or hospital services.

Parental occupational exposures and Ewing's sarcoma

A case-control study of Ewing's sarcoma (ES) was conducted to search for occupational exposures associated with ES. The study consisted of 196 cases and 196 random-digit controls matched on geographical region, gender, ethnic origin and birth date. A questionnaire was administered to mothers of participants to obtain information on medical conditions, medications, and parental occupations during and after the index pregnancy. An occupational exposure expert coded jobs and industries for possible and probable exposure to selected occupational hazards. Risk of ES was increased with probable parental exposure to wood dusts during their usual occupation post pregnancy (odds ration [OR] = 3.2; 95% confidence interval [CI] = 1.1-9.2). Other exposures, including a priori suspected risk factors such as exposure to pesticides and farm animals, were not significantly associated with ES. A history of household pesticide extermination was associated with ES among boys aged 15 or younger (OR = 3.0; 95% CI = 1.1-8.1), but not among girls or older boys. Our results suggest that earlier reports of associations of ES with parental farm employment may have been describing risks associated with organic dusts encountered when working on a farm, rather than agricultural exposures or other farming related exposures.

The Epidemiologic Approach to Pharmacogenomics

The epidemiologic approach enables the systematic evaluation of potential improvements in the safety and efficacy of drug treatment which might result from targeting treatment on the basis of genomic information. The main epidemiologic designs are the randomized control trial, the cohort study, and the case-control study, and derivatives of these proposed for investigating gene-environment interactions. However, no one design is ideal for every situation, and methodological issues, notably selection bias, information bias, confounding and chance, all play a part in determining which study design is best for a given situation. There is also a need to employ a range of different designs to establish a portfolio of evidence about specific gene-drug interactions. In view of the complexity of gene-drug interactions, pooling of data across studies is likely to be needed in order to have adequate statistical power to test hypotheses. We suggest that there may be opportunities (i) to exploit samples from trials already completed to investigate possible gene-drug interactions; (ii) to consider the use of the case-only design nested within randomized controlled trials as a possible means of reducing genotyping costs when dichotomous outcomes are being investigated; and (iii) to make use of population-based disease registries that can be linked with tissue samples, treatment information and death records, to investigate gene-treatment interactions in survival.

Ovarian cancer: the neglected diagnosis

OBJECTIVE

To investigate presenting signs and symptoms of ovarian cancer and stage of tumor in a community cohort of women with the diagnosis of ovarian cancer.

PATIENTS AND METHODS

We reviewed retrospectively the medical records of all women who sought primary and specialty care in Olmsted County, Minnesota, between January 1, 1985, and December 31, 1997, to evaluate presenting symptoms, time from first symptom to diagnosis of ovarian cancer, and stage of tumor at diagnosis.

RESULTS

Of 107 women with a diagnosis of ovarian cancer, the most commonly documented presenting symptom was crampy abdominal pain. Urinary symptoms and abdominal pain were the most commonly documented presenting symptom in patients with stage I and II ovarian cancers, whereas abdominal pain and increased abdominal girth were the most commonly documented symptoms in patients with stage III and IV cancer. Approximately 15% of tumors (n = 15) were found during routine evaluations or during a procedure for another problem. Less than 25% of presenting symptoms (n = 24 women) related directly to the pelvis or were more traditional gynecologic symptoms. Delays in women seeking medical care, health care system issues, competing medical conditions, physicians' failure to follow up, and women not returning for follow-up were associated with longer time to diagnosis.

CONCLUSION

Both stage I and II cancer are associated with symptoms, but few symptoms are directly related to the reproductive pelvic organs or unique to ovarian cancer. A longer interval from first sign or symptom to diagnosis of ovarian cancer is associated with both patient and health care system factors.

Polymorphisms XRCC1-R399Q and XRCC3-T241M and the Risk of Breast Cancer at the Ontario Site of the Breast Cancer Family Registry

This study investigates the role of two nonsynonymous single nucleotide polymorphisms in DNA repair genes, X-ray repair cross-complementing group 1 (XRCC1)-R399Q and X-ray repair cross-complementing group 3 (XRCC3)-T241M, in breast cancer. Incident cases of invasive breast cancer in Caucasian women [n = 402, mean age = 45.7 (SD = 6.2) years] and female Caucasian controls [n = 402, mean age = 45.2 (6.5) years] frequency matched on 5-year age intervals were identified from the Ontario Familial Breast Cancer Registry. No evidence for a main effect of the XRCC1-R399Q genotype on breast cancer risk was observed. Estimates of risk for a family history (FH) of breast cancer compared with no FH differed by XRCC1-R399Q genotype (P value for interaction = 0.001). Homozygote XRCC1-399 R/R individuals and FH+ were at a 2.92-fold [95% confidence interval (95% CI) = 1.47–5.79] increased risk of disease compared with FH− individuals; the estimate of risk increased for R/Q heterozygotes with FH+ [odds ratio (OR) = 3.85, 95% CI = 1.94–7.65] but not for Q/Q homozygotes with FH+ (OR = 0.54, 95% CI = 0.20–1.47) compared with homozygous R/R and FH− individuals. A marginal positive association for XRCC3-241 M/M compared with T/T genotype was found (OR = 1.44, 95% CI = 0.94–2.19), but the heterozygous T/M was not associated with an increase in risk (OR = 0.96, 95% CI = 0.71–1.32). There was also some evidence for a combined effect of body mass index and XRCC3-T241M on estimates of risk. Our results suggest that these polymorphisms may influence breast cancer risk by modifying the effect of risk factors such as FH. There is a need for further study into the role of these polymorphisms as effect modifiers.

Early life menstrual characteristics and pregnancy experiences among women with and without major depression: the Harvard study of moods and cycles

BACKGROUND

Other than premenstrual dysphoria, few studies have examined the extent to which basic characteristics of the menstrual cycle and the occurrence of other reproductive landmarks impact on the risk of major depression.

METHODS

From a population-based sample of 4161 premenopausal women 36-45 years of age, we identified 332 women who met DSM criteria for past or current major depression and a sample of 644 women with no such history. In person interviews included a detailed assessment of menstrual cycle characteristics from age at menarche through study enrollment as well as other reproductive landmarks.

RESULTS

Risk of depression increased significantly with decreasing age at menarche (P<0.001). The risk of depression was also higher in women with heavier menstrual flow and cycle irregularity during the first 5 years of menstruation. Women with a history of multiple abortions were 2-3-times more likely to develop major depression (95% CI 1.6-4.1). Increasing months of breastfeeding was associated with a decreased risk of depression after adjustment for education, marital status, and number of livebirths (P-value, test of trend=0.012). This association was largely confined to depression during the postpartum period.

LIMITATIONS

Menstrual and pregnancy history exposures were self-reported and retrospectively assessed. However, women with and without a HISTORY of depression were subject to similar recall requirements that likely resulted in an underestimate of most risk estimates.

CONCLUSIONS

Clinicians involved in routine obstetrical and gynecological care of women need to recognize that menstrual and pregnancy history events may serve as potential markers for subsequent psychiatric sequelae.

Quality of Life Following Treatment for Early Prostate Cancer: Does Low Dose Rate (LDR) Brachytherapy Offer a Better Outcome? A Review

OBJECTIVE

Due to a lack of evidence from randomised studies, there is little agreement on the best form of treatment among men who require curative treatment for prostate cancer. The relative impact of the various treatments on symptoms and health-related quality of life is also controversial. We review the literature on quality of life changes following low dose rate brachytherapy (BXT) and compare BXT to other treatments for early prostate cancer.

METHODS

Systematic literature review 1988-2003 (Medline).

KEYWORDS

Brachytherapy; Radical prostatectomy; External beam radiotherapy; Quality of life; Symptoms.

RESULTS

Review of the current literature suggests that radical prostatectomy, external beam radiotherapy and BXT either alone or in combination with supplementary external beam radiotherapy offer good long-term health-related quality of life. However differences exist in the toxicity of treatment in terms of erectile function, voiding difficulty, incontinence and bowel function. These differences seem to persist for at least 3-5 years post-treatment though longer-term quality of life outcomes from modern techniques are unknown.

CONCLUSION

BXT offers a high probability of maintaining continence, potency and normal rectal function though both storage and voiding urinary symptoms have been reported. Addition of androgen deprivation and EBRT to BXT may increase urinary, bowel and sexual toxicity of treatment. Quality of life outcome following brachytherapy compares favourably with other radical treatment options for the management of early prostate cancer.

Panic Disorder and Suicide Attempt in the National Comorbidity Survey

Clinical and some epidemiological data conflict concerning the likelihood of suicide attempt in individuals with panic disorder (PD). The purpose of this study was to illuminate the panic disorder-suicide attempt association in the National Comorbidity Survey (NCS; R. C. Kessler et al., 1994). Specifically, suicide attempt histories of those 5,872 respondents answering "yes" or "no" to the suicide attempt question were regressed against lifetime diagnostic histories. Lifetime PD history, in the presence of other disorders, was unrelated to elevated risk of suicide attempt and did not account for additional variance. PD respondents who had made a suicide attempt were characterized by Comorbidity. Epidemiological respondents with lifetime histories of PD alone are not at heightened risk for self-reported suicide attempt.

Radiation exposure from diagnostic imaging: agreement between self-report and medical records

Data on diagnostic imaging procedures from a highly structured interview were compared to medical records in a case-control study of radiography and acute myelogenous leukemia. Three hundred and twenty-eight cases and 315 controls (78% of participants) had medical records available from an average of 71% of providers. Proxies were used for 49% of cases because of rapid fatality. Mean agreement (number of procedures in medical records subtracted from number in interview) showed similar levels of overreporting in cases [0.6; 95% confidence interval (CI): 0.0, 1.1] and controls (0.7; CI: 0.2, 1.3) with few procedures (<= 10). Most participants with more procedures underreported exposure, and underreporting increased with increasing exposure, especially among cases [mean (CI) agreement = -2.1 (-4.3, 0.0) for 11-20 procedures, -6.4 (-13.6, 0.7) for >20 procedures] and case proxies. High-dose, fluoroscopic, and non-routine procedures were self-reported more accurately than low-dose, non-fluoroscopic, and routine procedures, respectively (p < 0.01 for each comparison), and tended to be underreported. Case-control differences in agreement were non-significant for these categories of procedures. We conclude that diagnostic imaging procedures of most interest to the AML-radiography hypothesis are self-reported accurately but that underreporting does occur and might lead to attenuated risk estimates.

Evidence of recall bias in volunteered vs. prompted responses about occupational exposures

BACKGROUND

Recall bias remains a concern in case-control studies, although few investigations have found evidence of differential recall. This study examined whether differences in occupational exposure reporting occur in volunteered vs. prompted questionnaire responses.

METHODS

In a large, population-based, case-control study of a childhood cancer, neuroblastoma, we calculated odds ratios for broad occupational exposure groups on the assumption that in the absence of recall bias, risk estimates for such broad groupings should be close to the null value.

RESULTS

Prompted exposures and work activities showed little evidence of differential recall by parents of cases and controls (all OR < 1.2), but case parents were more likely to volunteer information about other exposures or activities (ORs: 1.35-1.71). Case mothers were also more likely than control mothers to report activities involving indirect exposure (OR = 1.41).

CONCLUSIONS

These findings suggest that prompted exposure questions are less likely to be subject to recall bias than open-ended questions.

Accuracy of recall in health-related quality-of-life assessment among men treated for prostate cancer

PURPOSE

To determine the accuracy of patient recall of health-related quality of life (HRQOL) in men who have undergone radical prostatectomy for early-stage prostate cancer.

PATIENTS AND METHODS

Patients enrolled onto a longitudinal, observational cohort study of HRQOL after radical prostatectomy for early-stage prostate cancer were asked to assess their baseline HRQOL before surgery. They were later asked to recall their baseline HRQOL at intervals of 7 to 37 months after surgery. The two views of baseline HRQOL (actual and recall) were compared. HRQOL was measured with established instruments (the RAND 12-Item Short-Form Health Survey and a validated short form of the University of California Los Angeles Prostate Cancer Index) that addressed impairment in the physical, mental, urinary, bowel, and sexual domains.

RESULTS

Overall, recall was poor. Patients tended to remember their baseline HRQOL as being better than it actually was. This effect was particularly striking for urinary and sexual function. Greater education and younger age diminished this effect in some domains. The effect did not vary with time since surgery.

CONCLUSION

Men undergoing radical prostatectomy for early-stage prostate cancer do not accurately recall their pretreatment HRQOL when asked several months or years later. This recall bias is constant throughout a period of 6 months to 3 years after surgery. By collecting data before treatment and observing subjects longitudinally, investigators can ensure that HRQOL changes are analyzed in the context of any impairment that may have been present at baseline. If a longitudinal study is not feasible, then great caution must be used if patients are asked to recall their pretreatment HRQOL.

Relationship of psychiatric status to Gulf War veterans' health problems

OBJECTIVE

A growing body of research has shown that there are important links between certain psychiatric disorders and health symptom reporting. Two disorders in particular (posttraumatic stress disorder (PTSD) and major depression) have been the most widely implicated to date, and this association has sometimes been used to explain the occurrence of ill-defined medical problems and increased somatic symptoms in certain groups, most recently Gulf War veterans.

METHODS

Structured psychiatric diagnostic interviews were used to examine the presence of major psychiatric (axis I) disorders and their relation to health symptom reporting in a well-characterized, stratified subset of Gulf War veterans and a non-Gulf-deployed veteran comparison group.

RESULTS

Rates of most psychiatric disorders were substantially lower than national comorbidity estimates, consistent with prior studies showing heightened physical and emotional well-being among active-duty military personnel. Rates of PTSD and major depression, however, were significantly elevated relative to the veteran comparison group. The diagnosis of PTSD showed a small but significant association with increased health symptom reports. However, nearly two-thirds of Gulf participants reporting moderate to high health symptoms had no axis I psychiatric diagnosis.

CONCLUSIONS

Results suggest that rates of psychiatric illness were generally low with the exception of PTSD and major depression. Although PTSD was associated with higher rates of reported health problems, this disorder did not entirely account for symptoms reported by participants. Factors other than psychiatric status may play a role in Gulf War health problems.

Concerning the Suitability of Recordkeeping for Validating and Generalizing about Reports of Health-Related Information

Although the primary concern of validation studies is to assess the accuracy with which individuals report about behaviors or experiences, an important secondary concern of such studies is generalizability—the extent to which findings about the response validity of studied individuals are informative about the response validity of individuals who were not studied. Two recommendations are presented for assessing generalizability when participants contribute records to which subsequent reports are referred: (a) Reports should also be collected from a group of participants who do not keep such records and (b) control variables should be included in the design to evaluate the sensitivity of the studied measures to appropriate manipulations. These recommendations are described with examples of studies that have examined validity of reports about physical activity, menstrual distress, pain-related behaviors, and dietary intake.

An empirical investigation of exposure measurement bias and its components in case-control studies

This study investigated bias due to misclassification of exposure in case control studies. Using a metaanalysis of data from a number of case control studies, in which a possibly misclassified exposure was validated against a more reliable one, estimates of misclassification indices and bias were obtained. The estimates were used to investigate whether misclassification indices, in particular, sensitivity and specificity and so-called quality indices, are typically nondifferential with respect to cases and controls. It is concluded that quality indices do not show any tendency to be either lower or higher in cases than controls. On the other hand, sensitivity tends to be higher in cases than controls and specificity lower. Estimates of misclassification bias may be either positive or negative and are consistent with random variation; there is little to suggest that bias is present in the studies analyzed.

Maternal recall of distant pregnancy events

Women themselves are often the most convenient source of information regarding their pregnancy and birth outcomes such as prematurity. However, the ability of mothers to recall birth information and the accuracy of information they do recall has rarely been assessed. This study used a mail survey of women who delivered either term or preterm infants in Rochester, Minnesota, between 1980 and 1985. Maternal reports of circumstances and outcome of delivery were compared to data abstracted from the medical records. Maternal ability to recall and report events varied from 99.5% for smoking during pregnancy to 85% for infant's gestational age at birth. Agreement between medical record and maternal report was very high for perinatal events such as delivery by cesarean section, preexisting diabetes, and smoking. Percent negative agreement was quite high when comparing information on rare events such as placental abruption. Recall of gestational age was better for women delivering preterm infants but uncommon in all women. Maternal reports of perinatal events in which they directly participated such as cesarean section can be accurately and reliably reported 10 to 15 years after the birth. Gestational age is reported less accurately and with different rates of recall for mothers with term and preterm deliveries.

Assessment of exposure misclassification bias in case-control studies using validation data

It has recently been shown that the bias due to misclassification of a binary exposure in case-control studies can be simply expressed in terms of so-called quality indices. Quality indices are measures of the degree of misclassification that are symmetric with respect to the true and measured exposure. They can be estimated from sub-study validation data and used to estimate the bias. Bias is not present if quality indices are nondifferential with respect to cases and controls. In this article the sampling distribution of these indices is investigated by developing formulae for their standard errors and these formulae are used to derive the standard error of the estimated bias. Simulation studies are used to confirm the validity of the formulae. The formulae are used to assess the bias in two studies of risk factors for Sudden Infant Death Syndrome (SIDS) and can be applied to the assessment of diagnostic tests.

Psychological stress, cancer incidence and mortality from non-malignant diseases

Psychological stress has been claimed to contribute to the onset of cancer and to increase mortality from a number of non-malignant diseases. We investigated the effect of a genuine psychological stressor, i.e. cancer in a child, on the incidence of cancer and mortality from non-malignant diseases of 11,231 parents in a Danish nationwide population-based study. The children were identified from records in the Danish Cancer Registry for the period 1943-85; their parents were identified from population registers. Overall, 1665 parental malignancies were diagnosed from the date the cancer of the child was reported until 1992, compared with 1702 expected from national incidence rates, yielding standardized incidence ratios of 1.0 (95% confidence interval, 0.9-1.0) for all parents, 1.0 for mothers and 1.0 for fathers. No statistically significant deviation of the relative risk from unity was seen for any period of follow-up after the stressful event, and no excess risk was seen for any particular type of cancer. Moreover, a total of 2137 parental deaths were observed over the period 1974-92, compared with 2333 expected from national mortality rates, giving an overall standardized mortality ratio of 0.9 (range 0.9-1.0). No excess mortality was seen from causes associated with allergic illness, autoimmune conditions, chronic illness or changes in behaviour. Our data provide no support for the hypothesis of an association between psychological stress and the incidence of cancer or mortality from non-malignant diseases. We conclude that the human organism is highly adaptable, even to extreme psychological stress.