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At least 19 recordsLinked to original sources

Modern diagnostics in chronic myeloproliferative diseases (CMPDs).

According to the new WHO classification a group of chronic myeloproliferative diseases (CMPDs) were defined: chronic myeloid leukemia (CML), chronic neutrophilic leukemia (CNL), chronic eosinophilic leukemia and hypereosinophilic syndrome (CEL/HES), polycythemia vera (PV), chronic idiopathic myelofibrosis (with extramedullary hematopoiesis, CIMF), essential thrombocythemia (ET), and so called CMPD/unclassifiable. As clinical features and laboratory findings differ widely between these diseases several diagnostic approaches are mandatory at diagnosis for classification and are needed also for follow up studies, especially for the measurement of minimal residual disease (MRD). We here outline the laboratory set up at diagnosis and during follow up in CMPDs with specific focus on the respective therapeutical consequences. Only by using a comprehensive diagnostic panel including cytomorphology, cytogenetics, and molecular genetic methods establishing the correct diagnosis, optimizing treatment as well as evaluating treatment response is possible in CMPDs today.

Blood Cell Count↗

Residential proximity to electricity transmission and distribution equipment and risk of childhood leukemia, childhood lymphoma, and childhood nervous system tumors: systematic review, evaluation, and meta-analysis.

In 1979, Wertheimer and Leeper reported an increased risk of cancer mortality among children living near 'electrical wiring configurations' suggestive of high current flow. Since then, numerous, often inconclusively small, investigations with conflicting results have studied the possible association between exposure to electric and magnetic fields (EMF) and health effects. The high prevalence of exposure to EMF has drawn attention to the issue of carcinogenesis. We report here the results of a meta-analysis of 13 epidemiologic studies of residential proximity to electricity transmission and distribution equipment and risk of childhood leukemia, lymphoma, and nervous system tumors. The combined relative risks for leukemia, lymphoma, and nervous system tumors are 1.49 (95 percent confidence interval [CI] = 1.11-2.00); 1.58 (CI = 0.91-2.76); and 1.89 (CI = 1.34-2.67) respectively. The reports of the primary studies were evaluated for epidemiologic quality and adequacy of exposure assessment. We found no statistically significant relation between combined relative risk estimates and 15 indicators of epidemiologic quality. Assessment of EMF exposure in the primary studies was found to be imperfect and imprecise. Additional high quality epidemiologic research, incorporating comprehensive assessments of EMF exposure collected concurrently with surrogate measures of exposure, is needed to confirm these results.

Adolescent↗

Chronic bullous disease of childhood, childhood cicatricial pemphigoid, and linear IgA disease of adults. A comparative study demonstrating clinical and immunopathologic overlap.

Linear IgA disease of adults, chronic bullous disease of childhood, and the rare childhood cicatricial pemphigoid currently are regarded as separate clinical entities despite their many shared features. All are sulfone-responsive subepidermal bullous diseases associated with linear IgA deposition at the basement membrane zone. In this paper we present a long-term study of 25 cases of adult linear IgA disease, 25 cases of chronic bullous disease of childhood, and four cases of childhood cicatricial pemphigoid, which has revealed further similarities among all three groups. The morphology and distribution of the cutaneous and mucosal lesions were similar; mucosal involvement was present in 80% of patients with adult linear IgA disease, 64% of those with chronic bullous disease of childhood, and 100% of those with childhood cicatricial pemphigoid, and ocular scarring affected patients in all groups. Remission occurred in 64% of those with chronic bullous disease of childhood (the disease was active in 12% after puberty), 48% of those with adult linear IgA disease, and in no cases of childhood cicatricial pemphigoid. HLA B8 and circulating IgA anti-basement membrane zone antibody were more common in chronic bullous disease of childhood than adult linear IgA disease. There were no absolute differences among the three groups, and we suggest that adult linear IgA disease, chronic bullous disease of childhood, and childhood cicatricial pemphigoid are the same disease, with childhood cicatricial pemphigoid being a more severe form of chronic bullous disease of childhood.

Adolescent↗

Relationship of childhood abuse and household dysfunction to many of the leading causes of death in adults. The Adverse Childhood Experiences (ACE) Study.

BACKGROUND: The relationship of health risk behavior and disease in adulthood to the breadth of exposure to childhood emotional, physical, or sexual abuse, and household dysfunction during childhood has not previously been described. METHODS: A questionnaire about adverse childhood experiences was mailed to 13,494 adults who had completed a standardized medical evaluation at a large HMO; 9,508 (70.5%) responded. Seven categories of adverse childhood experiences were studied: psychological, physical, or sexual abuse; violence against mother; or living with household members who were substance abusers, mentally ill or suicidal, or ever imprisoned. The number of categories of these adverse childhood experiences was then compared to measures of adult risk behavior, health status, and disease. Logistic regression was used to adjust for effects of demographic factors on the association between the cumulative number of categories of childhood exposures (range: 0-7) and risk factors for the leading causes of death in adult life. RESULTS: More than half of respondents reported at least one, and one-fourth reported > or = 2 categories of childhood exposures. We found a graded relationship between the number of categories of childhood exposure and each of the adult health risk behaviors and diseases that were studied (P < .001). Persons who had experienced four or more categories of childhood exposure, compared to those who had experienced none, had 4- to 12-fold increased health risks for alcoholism, drug abuse, depression, and suicide attempt; a 2- to 4-fold increase in smoking, poor self-rated health, > or = 50 sexual intercourse partners, and sexually transmitted disease; and 1.4- to 1.6-fold increase in physical inactivity and severe obesity. The number of categories of adverse childhood exposures showed a graded relationship to the presence of adult diseases including ischemic heart disease, cancer, chronic lung disease, skeletal fractures, and liver disease. The seven categories of adverse childhood experiences were strongly interrelated and persons with multiple categories of childhood exposure were likely to have multiple health risk factors later in life. CONCLUSIONS: We found a strong graded relationship between the breadth of exposure to abuse or household dysfunction during childhood and multiple risk factors for several of the leading causes of death in adults.

Adult↗

Implications of childhood trauma for depressed women: an analysis of pathways from childhood sexual abuse to deliberate self-harm and revictimization.

OBJECTIVE: Data from depressed women with and without a history of childhood sexual abuse were used to characterize clinical features that distinguished the two groups and to examine relationships of childhood sexual abuse to lifetime deliberate self-harm and recent interpersonal violence. METHOD: One hundred twenty-five women with depressive disorders were interviewed and completed self-report questionnaires. Path analysis was used to examine relationships of several childhood and personality variables with deliberate self-harm in adulthood and recent interpersonal violence. RESULTS: Women with a childhood sexual abuse history reported more childhood physical abuse, childhood emotional abuse, and parental conflict in the home, compared to women without a childhood sexual abuse history. The two groups were similar in severity of depression, but the women with a childhood sexual abuse history were more likely to have attempted suicide and/or engaged in deliberate self-harm. The women with a history of childhood sexual abuse also became depressed earlier in life, were more likely to have panic disorder, and were more likely to report a recent assault. Path analysis confirmed the contributory role of childhood sexual abuse to deliberate self-harm and the significance of childhood physical abuse for recent interpersonal violence. CONCLUSIONS: Childhood sexual abuse is an important risk factor to identify in women with depression. Depressed women with a childhood sexual abuse history constitute a subgroup of patients who may require tailored interventions to combat both depression recurrence and harmful and self-defeating coping strategies.

Adaptation, Psychological↗

Family of origin history, psychological distress, quality of childhood memory, and content of first and recovered childhood memories.

OBJECTIVE: Individual differences in quality of childhood memory and recovered memories from childhood remain poorly understood. Therefore, this study tested several hypotheses which may help account for the large amount of variation that individuals report in the general quality of their childhood memory and the valence of the memories that many individuals report recovering from their childhoods. It was hypothesized that family of origin dysfunction would be associated with poorer childhood memory, that current depressed mood would be associated with impaired childhood recall and the recall of negative memories, and that the content of recovered childhood memories would be disproportionately negative because they include a significant number of memories which had been repressed or dissociated. METHOD: Questionnaires were administered to 553 college students, 27% of whom reported a history of child abuse. RESULTS: The participants reported substantial variation in the general quality of their childhood memories and also a wide variety of different types of experiences for both their first childhood memories and the recovered memories that most of them had from their childhoods. Weak associations were found between family of origin dysfunction and poorer general quality of childhood memory, but the study as a whole resulted in few significant findings. CONCLUSIONS: Only weak support was found for some of the factors that have been hypothesized to distort autobiographical memory. The substantial individual variation in childhood memory that has been reported by college student samples remains poorly understood.

Adult↗

Initial reliability and validity of the childhood trauma interview: a new multidimensional measure of childhood interpersonal trauma.

OBJECTIVE: The Childhood Trauma Interview, a new instrument for brief and comprehensive retrospective assessment of childhood interpersonal trauma, is presented with initial evidence of its reliability and validity. METHOD: Drug- or alcohol-dependent patients (N = 220) were given the Childhood Trauma Interview and a questionnaire measure of child abuse, the Childhood Trauma Questionnaire. Convergent and discriminant validity for the Childhood Trauma Interview were tested by comparing correlations between analogous and nonanalogous trauma scales to those of the Childhood Trauma Questionnaire. RESULTS: Interrater reliability for the majority of trauma dimensions measured by the Childhood Trauma Interview was very high (63% had intraclass correlations above 0.90). Principal-components analysis yielded six rotated factors that accounted for 74% of the variance among scores: separations and losses, physical neglect, emotional abuse or assault, physical abuse or assault, witnessing violence, and sexual abuse or assault. Since these six factors exactly represented the areas that the interview was designed to assess, the construct validity of the Childhood Trauma Interview was supported. Without exception, convergent correlations were significantly higher than discriminant correlations, and convergence was improved when multidimensional variables from the Childhood Trauma Interview and their interactions were regressed onto Childhood Trauma Questionnaire scores. CONCLUSIONS: These initial findings suggest that the Childhood Trauma Interview is a reliable and valid method for brief assessment of multiple dimensions of six types of childhood interpersonal trauma.

Adult↗

Childhood residential mobility and multiple health risks during adolescence and adulthood: the hidden role of adverse childhood experiences.

BACKGROUND: Throughout US history, US society has been characterized by its high degree of residential mobility. Previous data suggest a relationship between mobility and increased health risk, but this relationship might be confounded by unmeasured adverse childhood experiences (ACEs). OBJECTIVES: To examine the relationship of childhood residential mobility to health problems during adolescence and adulthood and to determine how much these apparent relationships may result from underlying ACEs. DESIGN, SETTING, AND PARTICIPANTS: Retrospective cohort study of 8116 adults who completed a survey that included childhood residential mobility, ACEs (childhood abuse, childhood neglect, and household dysfunction), and multiple health problems. MAIN OUTCOME MEASURES: Number of childhood residential moves and number of ACEs (ACE score) were assessed for relationships to depressed affect, attempted suicide, alcoholism, smoking, early sexual initiation, and teenaged pregnancy. RESULTS: After adjustment for demographic variables, the risk of high residential mobility during childhood (> or = 8 moves) was 1.7- to 3.1-fold for each ACE, and increased with the number of ACEs. Compared with respondents who never moved, the odds of health risk for respondents with high mobility during childhood ranged from 1.3 (for smoking) to 2.5 (for suicide). However, when the number of ACEs was entered into multivariate models, the relationship between mobility and health problems was greatly reduced. CONCLUSIONS: Adverse childhood experiences are strongly associated with frequent residential mobility. Moreover, the apparent relationship between childhood mobility and various health risks is largely explained by ACEs. Thus, previous studies showing a relationship between residential mobility and negative outcomes were likely confounded by unmeasured ACEs.

Adolescent↗

Social disadvantages in childhood and risk of all-cause death and cardiovascular disease in later life: a comparison of historical and retrospective childhood information.

BACKGROUND: Childhood socioeconomic circumstances have been shown to contribute to adult mortality. The purpose of this study was to compare the association between objective historical records and recalled questionnaire-based information on childhood socioeconomic position (SEP) with regard to cardiovascular and all-cause mortality. METHODS: We examined the association between a socially disadvantaged childhood and all-cause mortality, cardiovascular disease (CVD) mortality, coronary heart disease (CHD) mortality, and acute coronary events among male participants in the Kuopio Ischemic Heart Disease (KIHD) Risk Factor Study, a population-based cohort study in eastern Finland with follow-up until 2002. The historical data on childhood factors were collected from school health records (n = 698), mainly from the 1930s to the 1950s. Recall data on socioeconomic conditions in childhood were obtained from the baseline examinations of the KIHD cohort (n = 2,682) in 1984-89. RESULTS: According to original school health records the men who were socially disadvantaged in childhood had a 1.41-fold (95% confidence interval 1.01-1.97) age-adjusted and examination-year-adjusted risk of all-cause death, a 1.32-fold (0.83-2.11) risk of CVD death, a 1.48-fold (0.85-2.57) risk of CHD death, and a 1.50-fold (1.02-2.20) risk of acute coronary events. After adjustment for biological and behavioural risk factors and for the SEP in adulthood the association was attenuated in all-cause death but did not change in CVD death, CHD death, and acute coronary events. On the contrary, the questionnaire-based recalled childhood data on childhood SEP showed no associations with mortality or acute coronary events. CONCLUSIONS: With regard to adult mortality, the use of historical records concerning hygiene and living conditions collected in childhood may either provide more accurate measures of early-life socioeconomic conditions or capture more relevant aspects of childhood socioeconomic disadvantage than retrospective recall data.

Alcohol Drinking↗

Childhood epilepsy with occipital paroxysms and benign nocturnal childhood occipital epilepsy.

Two types of childhood epilepsy have recently been reported: childhood epilepsy with occipital paroxysms, and benign nocturnal childhood occipital epilepsy. This article reports the clinical evolution, electroencephalographic (EEG) changes, and response to therapy of eight children with childhood epilepsy with occipital paroxysms (five boys and three girls, aged from 1 1/12 to 8 years) and eight children with benign nocturnal childhood occipital epilepsy (six boys and two girls, aged from 1 4/12 to 8 3/12 years). A careful clinical and EEG follow-up of at least 7 years was carried out for all patients. At the end of follow-up, all but one of the patients with childhood epilepsy with occipital paroxysms were seizure-free, and only two were still receiving anticonvulsant drugs. All but three children had a normal EEG, and normal mental development was observed in all but two cases. Patients with benign nocturnal childhood occipital epilepsy had a good long-term prognosis; all but two children with benign nocturnal childhood occipital epilepsy had a normal EEG. These two patients showed learning disabilities and poor school performances, and required remedial education. Therefore, although childhood epilepsy with occipital paroxysms and benign nocturnal childhood occipital epilepsy are two different types of epilepsy, the long-term prognosis seems to be similar.

Anticonvulsants↗

[Childhood and myocardial infarct: socioeconomic and psychosocial influences in childhood on risk of myocardial infarct].

OBJECTIVES: Compared to the established risk factors of myocardial infarction (MI) little is known about the impact of socio-economic and psycho-social risk factors during childhood. METHODS: Based on the WHO MONICA infarction register of the Erfurt reporting unit (1990-1993), 129 male cases and 129 controls (patients of accident surgery without psychiatric or heart disease, matched by age groups) were surveyed by a qualitative interview. The MI risk was analysed for general conditions of childhood, stressful life events, serious changes during childhood, and dissatisfaction with childhood using univariate and multiple logistic regression models. RESULTS: A significantly higher risk was found for worse (OR = 5.1; CI: 1.5-18.1) and mediocre (OR = 2.0; CI: 1.0-4.1) housing conditions as well as migration (OR = 3.0; CI: 1.1-8.3) during childhood. A significantly increased risk of MI is also found for individuals who reported three or more stressful life events (OR = 3.2; CI: 1.1-9.4) during childhood. In comparison, smoking habits (current or ex-smokers)--an established impact factor on MI--was associated with a slightly lower risk (OR = 2.6; CI: 1.3-5.3). CONCLUSIONS: Both socio-economic determinants and psycho-social factors of childhood carry significant risk for myocardial infarction in later life. Our data support the hypothesis that risk factors of MI are affected and/or triggered by socio-economic living conditions during childhood in general, and by stressful life events during childhood in particular.

Adult↗

Relationship between dissociation, childhood sexual abuse, childhood physical abuse, and mental illness in a general population sample.

OBJECTIVE: The aim of this study was to examine the relationship between childhood sexual abuse, childhood physical abuse, current psychiatric illness, and measures of dissociation in an adult population. METHOD: The authors used a randomly selected sample of 1,028 individuals. Each subject completed a semistructured face-to-face interview that included measures of childhood sexual abuse, childhood physical abuse, DSM-III-R psychiatric diagnoses, and selected items from the Dissociative Experiences Scale. RESULTS: Many individuals experienced occasional dissociative symptoms, and 6.3% of the population suffered from three or more frequently occurring dissociative symptoms. Among these individuals, the rate of childhood sexual abuse was two and one-half times as high, the rate of physical abuse was five times as high, and the rate of current psychiatric disorder was four times as high as the respective rates for the other subjects. Logistic regression modeling showed that physical abuse and current psychiatric illness were directly related to a high rate of dissociative symptoms but sexual abuse was not. The influence of sexual abuse was due to its associations with current psychiatric illness and with childhood physical abuse. Childhood physical abuse was not directly related to current psychiatric illness. Its association appeared to be mediated by its link to childhood sexual abuse. CONCLUSIONS: This study confirms that a small proportion (approximately 6%) of the general population suffer from high levels of dissociative symptoms. It calls into question the hypothesized direct relationship between childhood sexual abuse and adult dissociative symptoms.

Adolescent↗

Genetic determinants of childhood blood pressure and heart rate in relation to adult health outcomes: the consortium of childhood blood pressure.

BACKGROUND AND AIMS: To elucidate the genetic architecture of blood pressure (BP) and heart rate (HR) during early life and assess their potential relevance to adult health outcomes. METHODS: The largest genome-wide association study (GWAS) meta-analyses to date of childhood systolic BP, diastolic BP, pulse pressure, and mean arterial pressure (n = 28 425) and HR (n = 22 565) were conducted in children of European ancestry aged 4-17 years. Follow-up analyses included comparisons with adult GWAS results, polygenic risk score (PRS) analyses in independent cohorts of diverse ancestries, and a phenome-wide association study in the UK Biobank. RESULTS: Eight genome-wide significant loci were identified for childhood BP (KIAA2013, CACNB2, PLCE1, PAX2, COL4A2, RP11-236L14.1, CFDP1, TPX2) and three loci for childhood HR (CCDC141, ACHE, MYH6); all novel in children but previously reported in adults. Childhood PRSs explained up to 1.6% of BP variance and 5.2% of HR variance among children of European ancestry. Genetic correlations between childhood and adulthood BP traits were moderate (rg = 0.4-0.7), suggesting age-specific genetic effects on BP. In the UK Biobank, higher childhood BP PRS levels were significantly associated with a broad range of adult health outcomes, particularly cardiometabolic outcomes such as hypertension, angina, myocardial infarction, and cardiovascular disease-related mortality. CONCLUSIONS: These findings advance the understanding of the genetic architecture of childhood BP and HR and provide compelling genetic evidence linking childhood BP to a broad spectrum of adult health outcomes-particularly cardiometabolic conditions-which may inform targeted prevention strategies from a young age.

Humans↗

[On schizophrenic cases which present neurosis-like symptoms from early childhood--in relation to the prodromal signs and childhood schizophrenia].

The concept of "childhood schizophrenia" is ambiguous because of problems on the diagnostic level, especially in regard to symptomatology and prognosis. After studies which produced the description of "early infantile autism", childhood schizophrenia studies were even more confused. One reason for this was that there were not sufficient follow-up studies about the schizophrenia-like psychoses during occurring childhood, on the one hand, and the retrospective-anamnestic research was limited in the field of adult psychiatry, on the other hand. The author has focused on two points of view in order to discuss the problem of childhood schizophrenia. One is the non outbreak of childhood psychoses in children from 6 to 8 years old which was demonstrated by a couple of epidemiological research studies. The other is the concept of "Knick" (in Germany) which usually accompanies classical German theories of schizophrenia. "Knick" means that, at some point in the patient's history, there is an incident that is the indication of the onset of schizophrenia. The subjects were selected from the author's own cases. They continuously and insidiously developed schizophrenic symptoms during pre-puberty and puberty, presenting behavioral abnormalities or neurosis-like signs from early childhood. The diagnostic criteria for schizophrenia corresponds to DSM-III and with the German theory of Bleuler and Schneider. All cases have been treated for more than ten years. The acute onset cases, the mentally retarded cases (DSM-III .318) and the cases with suspected organic brain disorders were excluded because of the diagnostic problems. The author could differentiate these subjects into three groups based on the development in the infantile stage. The first was autistic group and the second mentally subnormal (DSM-III .317) or borderline group. Psychiatric problems of these two groups were already obvious in early childhood. The third group developed normally until they were 3-5 years old. After that they presented neurotic symptoms having some kind of intra-familiar problems. The author could confirm that these three groups manifested various kinds of neurosis-like symptoms, mainly obsessive-compulsive ones, from 3-5 years old. The so-called latent time, which is thought to be a non-outbreak time of childhood psychoses, may correspond to the prodromal stage of schizophrenia in these cases. This research is based on study of 31 children. An in-depth study has been done by the author of 6 of these children, 2 in each of the 3 categories described above. The "Knick"-points were not identifiable in these cases.(ABSTRACT TRUNCATED AT 400 WORDS)

Adolescent↗

Childhood abuse, household dysfunction, and the risk of attempted suicide throughout the life span: findings from the Adverse Childhood Experiences Study.

CONTEXT: Suicide is a leading cause of death in the United States, but identifying persons at risk is difficult. Thus, the US surgeon general has made suicide prevention a national priority. An expanding body of research suggests that childhood trauma and adverse experiences can lead to a variety of negative health outcomes, including attempted suicide among adolescents and adults. OBJECTIVE: To examine the relationship between the risk of suicide attempts and adverse childhood experiences and the number of such experiences (adverse childhood experiences [ACE] score). DESIGN, SETTING, AND PARTICIPANTS: A retrospective cohort study of 17 337 adult health maintenance organization members (54% female; mean [SD] age, 57 [15.3] years) who attended a primary care clinic in San Diego, Calif, within a 3-year period (1995-1997) and completed a survey about childhood abuse and household dysfunction, suicide attempts (including age at first attempt), and multiple other health-related issues. MAIN OUTCOME MEASURE: Self-reported suicide attempts, compared by number of adverse childhood experiences, including emotional, physical, and sexual abuse; household substance abuse, mental illness, and incarceration; and parental domestic violence, separation, or divorce. RESULTS: The lifetime prevalence of having at least 1 suicide attempt was 3.8%. Adverse childhood experiences in any category increased the risk of attempted suicide 2- to 5-fold. The ACE score had a strong, graded relationship to attempted suicide during childhood/adolescence and adulthood (P<.001). Compared with persons with no such experiences (prevalence of attempted suicide, 1.1%), the adjusted odds ratio of ever attempting suicide among persons with 7 or more experiences (35.2%) was 31.1 (95% confidence interval, 20.6-47.1). Adjustment for illicit drug use, depressed affect, and self-reported alcoholism reduced the strength of the relationship between the ACE score and suicide attempts, suggesting partial mediation of the adverse childhood experience-suicide attempt relationship by these factors. The population-attributable risk fractions for 1 or more experiences were 67%, 64%, and 80% for lifetime, adult, and childhood/adolescent suicide attempts, respectively. CONCLUSIONS: A powerful graded relationship exists between adverse childhood experiences and risk of attempted suicide throughout the life span. Alcoholism, depressed affect, and illicit drug use, which are strongly associated with such experiences, appear to partially mediate this relationship. Because estimates of the attributable risk fraction caused by these experiences were large, prevention of these experiences and the treatment of persons affected by them may lead to progress in suicide prevention.

Adolescent↗

Maternal occupational exposure to electromagnetic fields before, during, and after pregnancy in relation to risks of childhood cancers: findings from the Oxford Survey of Childhood Cancers, 1953-1981 deaths.

BACKGROUND: The concern that maternal exposure to electromagnetic fields (EMF) might be related to childhood cancer risks, particularly leukemia risks. METHODS: Maternal occupational data already collected as part of the Oxford Survey of Childhood Cancers have been reviewed. Information on occupations held before, during, and after the pregnancy was sought for 15,041 children dying of cancer in Great Britain in the period 1953-1981, and for an equal number of matched controls. Each period of working was classified under one of five headings: (1) sewing machinist; (2) textile industry workers (other than sewing machinists) with likely exposures to EMF; (3) other machinists and other jobs with likely "higher" EMF exposure; (4) other jobs with likely exposure to some EMF, and (5) jobs with little potential for EMF exposure. RESULTS: Relative to risks in the children of mothers who held occupations with little potential for EMF exposure during pregnancy (a category that included housewives), risks of all childhood cancers were close to unity both for the children of sewing machinists (22 case and 31 control mothers, RR 0.72, 95% CI 0.42 to 1.25) and for the children of other machinists with likely "higher" EMF exposures (44 case and 47 control mothers, RR 0.93, 95% CI 0.61 to 1.41). Corresponding risks for all childhood leukemias and for all childhood brain cancers were similarly unexceptional. Simultaneous adjustment for social class, maternal age at birth of child, and sibship position had little effect. CONCLUSIONS: The study findings did not indicate that maternal occupational exposure to EMF during pregnancy is a risk factor for childhood leukemias, childhood brain cancers, or the generality of all childhood cancers.

Adolescent↗

Clustering of childhood leukaemia in Hong Kong: association with the childhood peak and common acute lymphoblastic leukaemia and with population mixing.

Incidence data of childhood leukaemia (CL) in Hong Kong (1984-90) have been analysed for evidence of variation between small areas. All cases (n=261) were classified by morphological cell type, with the majority (n=205) being acute lymphoblastic leukaemia (ALL), and haematological review has permitted immunophenotypic classification for 73% of these. The data have been examined for evidence of spatial clustering within small census areas (TPUs) and for association with population mixing, with attention focused on those subgroups (especially the childhood peak of ALL--taken here to be diagnoses in children from 24 months up to the seventh birthday--and common ALL) which, it has been hypothesized, may be caused by unusual patterns of exposure and response to common infections. For the whole of Hong Kong, there was evidence of spatial clustering of ALL at ages 0-4 years (P = 0.09) and in the childhood peak (P<0.05). When these analyses were restricted to TPUs where extreme population mixing may have occurred, overall incidence was elevated and significant evidence of clustering was found for ALL (P<0.007) at these ages and for the common ALL in the childhood peak (P = 0.032). Replication of the analyses for subsets of leukaemia that were not dominated by the childhood peak of ALL found no evidence of clustering. This is the first investigation of an association between population mixing and childhood leukaemia in Asia and the first to include clustering and to consider particular subsets. The results are supportive of the 'infectious' aetiology hypothesis for subsets of childhood leukaemia, specifically common ALL in the childhood peak.

Adolescent↗

Primary thyroid cancer after a first tumour in childhood (the Childhood Cancer Survivor Study): a nested case-control study.

BACKGROUND: Survivors of malignant disease in childhood who have had radiotherapy to the head, neck, or upper thorax have an increased risk of subsequent primary thyroid cancer, but the magnitude of risk over the therapeutic dose range has not been well established. We aimed to quantify the long-term risk of thyroid cancer after radiotherapy and chemotherapy. METHODS: In a nested case-control study, 69 cases with pathologically confirmed thyroid cancer and 265 matched controls without thyroid cancer were identified from 14,054 5-year survivors of cancer during childhood from the Childhood Cancer Survivor Study cohort. Childhood cancers were diagnosed between 1970 and 1986 with cohort follow-up to 2000. FINDINGS: Risk of thyroid cancer increased with radiation doses up to 20-29 Gy (odds ratio 9.8 [95% CI 3.2-34.8]). At doses greater than 30 Gy, a fall in the dose-response relation was seen. Both the increased and decreased risks were more pronounced in those diagnosed with a first primary malignant disease before age 10 years than in those older than 10 years. Furthermore, the fall in risk remained when those diagnosed with Hodgkin's lymphoma were excluded. Chemotherapy for the first cancer was not associated with thyroid-cancer risk, and it did not modify the effect of radiotherapy. 29 (42%) cases had a first diagnosis of Hodgkin's lymphoma compared with 49 (19%) controls. 11 (42%) of those who had Hodgkin's lymphoma had subsequent thyroid cancers smaller than 1 cm compared with six (17%) of those who had other types of childhood cancer (p=0.07). INTERPRETATION: The reduction in radiation dose-response for risk of thyroid cancer after childhood exposure to thyroid doses higher than 30 Gy is consistent with a cell-killing effect. Standard long-term follow-up of patients who have had Hodgkin's lymphoma for detection of thyroid cancer should also be undertaken for survivors of any cancer during childhood who received radiotherapy to the thorax or head and neck region.

Adolescent↗