Biomedical subjects

A J Swerdlow

Publications and source records attributed to A J Swerdlow.

At least 19 recordsLinked to original sources

PubMed2007

Medical history, cigarette smoking and risk of acoustic neuroma: an international case-control study.

Acoustic neuroma (vestibular schwannoma) is a benign tumor of the vestibulocochlear nerve. Its recorded incidence is increasing but risk factors for this tumor have scarcely been investigated. We conducted a population-based case-control study of risk factors for acoustic neuroma in the UK and Nordic countries, including 563 cases and 2,703 controls. Tumor risk was analyzed in relation to medical history and cigarette smoking. Risk of acoustic neuroma was significantly raised in parous compared with nulliparous women (OR = 1.7, 95% CI: 1.1-2.6), but was not related to age at first birth or number of children. Risk was not associated with a history of allergic disease, past head injury, past diagnosis of a neoplasm or birth characteristics, but was significantly raised for past diagnosis of epilepsy (OR = 2.5, 95% CI: 1.3-4.9). Tumor risk was significantly reduced in subjects who had ever regularly smoked cigarettes (OR = 0.7, 95% CI: 0.6-0.9), but the reduction applied only to current smokers (OR = 0.5, 95% CI: 0.4-0.6), not ex-smokers (OR = 1.0, 95% CI: 0.8-1.3). The reduced risk of acoustic neuroma in smokers and raised risk in parous women might relate to sex hormone levels, or smoking might suppress tumor growth, but effects of parity and smoking on timing of diagnosis of the tumor are also a potential explanation. The raised risk in relation to past diagnosis of epilepsy might be a surveillance artefact or imply that epilepsy and/or antiepileptic medication use predispose to acoustic neuroma. These findings need replication by other studies and possible mechanisms need to be clarified.

Adolescent↗

PubMed2006

History of allergic disease and risk of meningioma.

Epidemiologic studies have consistently shown inverse associations of allergic disease with risk of glioma, but it is unclear whether this association also applies to meningioma. The authors conducted a pooled analysis of meningioma risk in relation to a history of allergic disease based on data from two population-based, case-control studies with 475 cases and 1,716 controls in the United Kingdom (2001-2004). Meningioma risk was significantly reduced in relation to self-reported, physician-diagnosed allergic disease (odds ratio = 0.76, 95% confidence interval (CI): 0.61, 0.96) but was nonsignificantly reduced for individual conditions: asthma (odds ratio = 0.85, 95% CI: 0.61, 1.18), hay fever (odds ratio = 0.81, 95% CI: 0.62, 1.06), and eczema (odds ratio = 0.72, 95% CI: 0.51, 1.02). Risk reductions were greatest for asthma (odds ratio = 0.43, 95% CI: 0.21, 0.89) and hay fever (odds ratio = 0.50, 95% CI: 0.25, 1.00) with an early age at onset (<10 years) and for eczema (odds ratio = 0.46, 95% CI: 0.21, 1.07) with an onset at ages 10-19 years; they were near unity for onset in adulthood. This study suggests an inverse association between a history of allergies and meningioma risk, but with smaller risk reductions than for glioma. The reasons for this association need clarification, as well as an etiologic explanation. Consideration also needs to be given to confounding or bias.

Adolescent↗

PubMed2005

Mobile phone use and risk of acoustic neuroma: results of the Interphone case-control study in five North European countries.

There is public concern that use of mobile phones could increase the risk of brain tumours. If such an effect exists, acoustic neuroma would be of particular concern because of the proximity of the acoustic nerve to the handset. We conducted, to a shared protocol, six population-based case-control studies in four Nordic countries and the UK to assess the risk of acoustic neuroma in relation to mobile phone use. Data were collected by personal interview from 678 cases of acoustic neuroma and 3553 controls. The risk of acoustic neuroma in relation to regular mobile phone use in the pooled data set was not raised (odds ratio (OR) = 0.9, 95% confidence interval (CI): 0.7-1.1). There was no association of risk with duration of use, lifetime cumulative hours of use or number of calls, for phone use overall or for analogue or digital phones separately. Risk of a tumour on the same side of the head as reported phone use was raised for use for 10 years or longer (OR = 1.8, 95% CI: 1.1-3.1). The study suggests that there is no substantial risk of acoustic neuroma in the first decade after starting mobile phone use. However, an increase in risk after longer term use or after a longer lag period could not be ruled out.

Case-Control Studies↗

PubMed2005

Cancer incidence and mortality in patients with insulin-treated diabetes: a UK cohort study.

Raised risks of several cancers have been found in patients with type II diabetes, but there are few data on cancer risk in type I diabetes. We conducted a cohort study of 28 900 UK patients with insulin-treated diabetes followed for 520 517 person-years, and compared their cancer incidence and mortality with national expectations. To analyse by diabetes type, we examined risks separately in 23 834 patients diagnosed with diabetes under the age of 30 years, who will almost all have had type I diabetes, and 5066 patients diagnosed at ages 30-49 years, who probably mainly had type II. Relative risks of cancer overall were close to unity, but ovarian cancer risk was highly significantly raised in patients with diabetes diagnosed under age 30 years (standardised incidence ratio (SIR)=2.14; 95% confidence interval (CI) 1.22-3.48; standardised mortality ratio (SMR)=2.90; 95% CI 1.45-5.19), with greatest risks for those with diabetes diagnosed at ages 10-19 years. Risks of cancer at other major sites were not substantially raised for type I patients. The excesses of obesity- and alcohol-related cancers in type II diabetes may be due to confounding rather than diabetes per se.

Adolescent↗

PubMed2005

Birthweight and other pregnancy outcomes in a cohort of women with pre-gestational insulin-treated diabetes mellitus, Scotland, 1979-95.

AIMS: To assess pregnancy outcomes, in particular birthweight, in a large population-based cohort of women in Scotland with pre-gestational insulin-treated diabetes mellitus. METHODS: Data about diabetes from the Diabetes UK cohort were linked to data on births from the Scottish Hospital In-Patient Record System. This identified 1112 eligible singleton deliveries during 1979-95 to 706 insulin-treated women. RESULTS: One thousand and eighty-four (97.5%) deliveries resulted in a live-born infant and 28 (2.5%) in a stillbirth. There were 13 (1.2%) neonatal deaths. The mean birthweight of the live-born infants was 3421 g, 1.06 standard deviations greater than that of infants in the Scottish general population after correcting for sex and gestational age. Forty-three per cent of live-born babies in the study were large (> Scottish 90th percentile) and 4% small (< 10th percentile) for their sex and gestational age. Macrosomia, defined as birthweight > or = 4000 g, occurred in 23% live-born babies and its prevalence was significantly inversely related to duration of maternal diabetes. However, the mean birthweight of infants born to mothers with diabetes for 20 or more years was still 0.90 standard deviations greater than in the general population. Prevalence of macrosomia increased with increasing number of previous pregnancies, but was not associated with maternal height or smoking habits. Stillbirth and neonatal death rates were, respectively, 4.7 (95% confidence interval = 3.3, 6.8) and 2.4 (1.4, 4.1), times higher than those in the general population. CONCLUSIONS: The frequency of adverse pregnancy outcomes in women with pre-existing insulin-treated diabetes was much higher than in the Scottish general population, and changed little during the study period. A detailed quantification of the independent effect of duration of mother's diabetes on birthweight revealed a continuous inverse correlation between these two variables.

Adult↗

PubMed2004

Second primary breast cancer after Hodgkin's disease.

Although the potential carcinogenic risk of radiotherapy is well known, it has become clear that there is a particularly high risk of radiation-induced breast cancer in women treated for Hodgkin's disease at young ages. Thankfully, death from breast cancer in this population is uncommon, but it is important to understand factors contributing to the risk, including treatment parameters, and to develop a logical and efficient method for medical management of those at risk. In this minireview, we examine the evidence which should inform such a management policy.

Female↗

PubMed2004

Mortality of South Asian patients with insulin-treated diabetes mellitus in the United Kingdom: a cohort study.

AIMS: To investigate mortality in South Asian patients with insulin-treated diabetes and compare it with mortality in non South Asian patients and in the general population. METHODS: A prospective cohort study was conducted of 828 South Asian and 27 962 non South Asian patients in the UK with insulin-treated diabetes diagnosed at ages under 50 years. The patients were followed for up to 28 years. Ethnicity was determined by analysis of names. Standardized mortality ratios (SMRs) were calculated, comparing mortality in the cohort with expectations from the mortality experience of the general population. RESULTS: SMRs were significantly raised in both groups of patients, particularly the South Asians, and especially in women and subjects with diabetes onset at a young age. The SMRs for South Asian patients diagnosed under age 30 years were 3.9 (95% CI 2.0-6.9) in men and 10.1 (5.6-16.6) in women, and in the corresponding non South Asians were 2.7 (2.6-2.9) and 4.0 (3.6-4.3), respectively. The SMR in women was highly significantly greater in South Asians than non South Asians. The mortality in the young-onset patients was due to several causes, while that in the patients diagnosed at ages 30-49 was largely due to cardiovascular disease, which accounted for 70% of deaths in South Asian males and 73% in females. CONCLUSIONS: South Asian patients with insulin-treated diabetes suffer an exceptionally high mortality. Clarification of the full reasons for this mortality are needed, as are measures to reduce levels of known cardiovascular disease risk factors in these patients.

Adult↗

PubMed2003

Creutzfeldt-Jakob disease in United Kingdom patients treated with human pituitary growth hormone.

OBJECTIVE: To investigate risk factors for Creutzfeldt-Jakob disease (CJD) in patients in the United Kingdom treated with human pituitary growth hormone (hGH). METHODS: Incidence rates of CJD, based on person-year denominators, were assessed in a cohort of 1,848 patients treated with hGH in the United Kingdom from 1959 through 1985 and followed to the end of 2000. RESULTS: CJD developed in 38 patients. Risk of CJD was significantly increased by treatment with hGH prepared by the Wilhelmi method of extraction from human pituitaries. Risk was further raised if this treatment was administered at ages 8 to 10 years. The peak risk of CJD was estimated to occur 20 years after first exposure, and the estimated lifetime cumulative risk of CJD in Wilhelmi-treated patients was 4.5%. CONCLUSIONS: Size-exclusion chromatography, used in non-Wilhelmi preparation methods, may prevent CJD infection. Susceptibility to CJD may vary with age, and susceptibility may be present in only a few percent of the population.

Adolescent↗

PubMed2003

Life-course body size and perimenopausal mammographic parenchymal patterns in the MRC 1946 British birth cohort.

Dense mammographic parenchymal patterns are associated with an increased risk of breast cancer. Certain features of body size have been found to be associated with breast cancer risk, but less is known about their relation to breast density. We investigated the association of birth size, childhood growth and life-course changes in body size with Wolfe grade in 1298 perimenopausal women from a British cohort of women born in 1946. The cohort benefits from repeated measures of body size in childhood and adulthood. We obtained mammograms for 90% of women who at age 53 years reported having previously had a mammogram. We found no associations with birth weight or maximum attained height. Body mass index (BMI) at age 53 years and breast size were independently and inversely associated with Wolfe grade (P-value for trend <0.001 for both). Women who reached puberty later were at a greater odds of a higher Wolfe grade than women who had an earlier puberty (odds ratio associated with a 1 year delay in menarche 1.14, 95% CI: 1.01-1.27, adjusted for BMI and breast size at mammography). A higher BMI at any age during childhood or adult life was associated with a reduction in the odds of a higher Wolfe grade, after controlling for breast size and BMI at mammography, for example, standardised odds ratio for height at age 7 was 0.72 (95% CI: 0.64, 0.81). These findings reveal the importance of taking life-course changes in body size, and not just contemporaneous measures, into account when using mammographic density as an intermediate marker for risk of breast cancer.

Adolescent↗

PubMed2003

Mortality from heart disease in a cohort of 23,000 patients with insulin-treated diabetes.

AIMS/HYPOTHESIS: Although ischaemic heart disease is the predominant cause of mortality in older people with diabetes, age-specific mortality rates have not been published for patients with Type 1 diabetes. The Diabetes UK cohort, essentially one of patients with Type 1 diabetes, now has sufficient follow-up to report all heart disease, and specifically ischaemic heart disease, mortality rates by age. METHODS: A cohort of 23,751 patients with insulin-treated diabetes, diagnosed under the age of 30 years and from throughout the United Kingdom, was identified during the period 1972 to 1993 and followed for mortality until December 2000. Age- and sex-specific heart disease mortality rates and standardised mortality ratios were calculated. RESULTS: There were 1437 deaths during the follow-up, 536 from cardiovascular disease, and of those, 369 from ischaemic heart disease. At all ages the ischaemic heart disease mortality rates in the cohort were higher than in the general population. Mortality rates within the cohort were similar for men and women under the age of 40. The standardised mortality ratios were higher in women than men at all ages, and in women were 44.8 (95%CI 20.5-85.0) at ages 20-29 and 41.6 (26.7-61.9) at ages 30-39. CONCLUSIONS/INTERPRETATION: The risk of mortality from ischaemic heart disease is exceptionally high in young adult women with Type 1 diabetes, with rates similar to those in men with Type 1 diabetes under the age of 40. These observations emphasise the need to identify and treat coronary risk factors in these young patients.

Adolescent↗

PubMed2003

Epidemiology of Hodgkin's disease and non-Hodgkin's lymphoma.

This review considers in detail the descriptive and aetiological epidemiology of Hodgkin's disease and non-Hodgkin's lymphoma (NHL), with attention to histological subcategories when the literature allows. The aetiology of Hodgkin's disease remains only partially understood. There is evidence that Epstein-Barr virus (EBV) may be involved in the causation of some cases, and clinical immune deficiency is a risk factor for a few, but the evidence is not entirely consistent and other factors may also be important in causing the EBV-associated cases of Hodgkin's disease. The cause of EBV-unassociated cases remains obscure. For NHL, although it has been shown that some cases are related to immune deficiency and chronic antigenic stimulation, and especially to EBV in the context of immune deficiency, the causation of the majority of cases remains unknown. The increasing incidence of NHL, other than that related to AIDS, is also essentially unexplained. Epidemiological investigation of the aetiology of NHL and Hodgkin's disease is making steady progress, however, and there remain leads to be followed that may result in a better understanding and hence prevention.

Epstein-Barr Virus Infections↗

PubMed2002

Risk of cancer in patients treated with human pituitary growth hormone in the UK, 1959-85: a cohort study.

BACKGROUND: Growth hormone raises serum concentrations of insulin-like growth factor IGF-I, which is mitogenic and antiapoptotic. There is evidence that raised endogenous levels of growth hormone and IGF-I might be associated with increased risk of certain solid cancers, but there have been no data on long-term risks of solid cancers after growth hormone treatment. METHODS: We did a cohort study to investigate cancer incidence and mortality in 1848 patients in the UK who were treated during childhood and early adulthood with human pituitary growth hormone during the period from 1959 to 1985. Patients were followed up for cancer incidence to December, 1995 and for mortality to December, 2000. Risk of cancer in the cohort was compared with that in the general population, controlling for age, sex, and calendar period. FINDINGS: Patients treated with human pituitary growth hormone had significantly raised risks of mortality from cancer overall (standardised mortality ratio 2.8, 95% CI 1.3-5.1; ten cases), colorectal cancer (10.8, 1.3-38.8; two cases), and Hodgkin's disease (11.4, 1.4-41.3; two cases). Incidence of colorectal cancer was also greatly raised (7.9, 1.0-28.7). After exclusion of patients whose original diagnosis rendered them at high risk of cancer, the significance and size of the risks of colorectal cancer incidence and mortality, and of Hodgkin's disease mortality were increased. INTERPRETATION: Although based on small numbers, the risk of colorectal cancer is of some concern and further investigation in other cohorts is needed. We have no evidence as to whether growth hormone in modern dosage regimens is associated with an increased risk of colorectal cancer.

Adolescent↗

PubMed2002

A pooled analysis of 10 case-control studies of melanoma and oral contraceptive use.

Data regarding the effects of oral contraceptive use on women's risk of melanoma have been difficult to resolve. We undertook a pooled analysis of all case-control studies of melanoma in women completed as of July 1994 for which electronic data were available on oral contraceptive use along with other melanoma risk factors such as hair colour, sun sensitivity, family history of melanoma and sun exposure. Using the original data from each investigation (a total of 2391 cases and 3199 controls), we combined the study-specific odds ratios and standard errors to obtain a pooled estimate that incorporates inter-study heterogeneity. Overall, we observed no excess risk associated with oral contraceptive use for 1 year or longer compared to never use or use for less than 1 year (pooled odds ratio (pOR)=0.86; 95% CI=0.74-1.01), and there was no evidence of heterogeneity between studies. We found no relation between melanoma incidence and duration of oral contraceptive use, age began, year of use, years since first use or last use, or specifically current oral contraceptive use. In aggregate, our findings do not suggest a major role of oral contraceptive use on women's risk of melanoma.

Adolescent↗

PubMed2001

Cancer incidence in the Falkland Islands.

Cancer incidence in the Falkland Islands, 1989-2000, was compared with rates in England and Wales, from which most Islanders originate. Colon and rectum cancer incidence was significantly raised 1989-93 but greatly reduced after 1994, when colonoscopic screening in high-risk families and sigmoidoscopic screening in the general population were introduced.

Colonic Neoplasms↗

PubMed2001

Lung cancer after Hodgkin's disease: a nested case-control study of the relation to treatment.

PURPOSE: To investigate the causes of the raised risk of lung cancer in patients who have had Hodgkin's disease, and in particular the relationship to treatment. PATIENTS AND METHODS: A nested case-control study was conducted within a cohort of 5,519 patients with Hodgkin's disease treated in Britain during 1963 through 1993. For 88 cases of lung cancer and 176 matched control subjects, information on treatment and other risk factors was extracted from hospital case-notes, and odds ratios for lung cancer in relation to these factors were calculated. RESULTS: Risk of lung cancer was borderline significantly greater in patients treated with mechlorethamine, vincristine, procarbazine, and prednisone (MOPP) chemotherapy than those who did not receive this treatment (relative risk [RR] = 1.66; 95% confidence interval [CI], 0.99 to 2.82), and increased with number of cycles of MOPP (P =.07). Exclusion of lung cancers for which histologic confirmation was not available strengthened these associations (RR = 2.41; 95% CI, 1.33 to 4.51; P =.004 for any MOPP and P =.007 for trend with number of cycles of MOPP). Risks were not raised, however, after chlorambucil, vinblastine, procarbazine, and prednisone treatment. There was evidence that the raised risk of lung cancer occurring in relation to radiotherapy was restricted to histologies other than adenocarcinoma. CONCLUSION: The results suggest that MOPP chemotherapy may lead to elevated risk of lung cancer, at least in certain subgroups of patients. The role of chemotherapy in the etiology of lung cancer after Hodgkin's disease deserves further investigation.

Adult↗

PubMed2001

Season of birth and diagnosis of children with leukaemia: an analysis of over 15 000 UK cases occurring from 1953-95.

If infections are involved in the aetiology of childhood leukaemia then seasonal variation in the birth or onset dates of the malignancy may be apparent. Previous studies that have examined seasonality of these dates have produced conflicting results. Using population-based data from the National Registry of Childhood Tumours we conducted a larger study than any to date of 15 835 cases of childhood leukaemia born and diagnosed in the UK between 1953-95. We found no evidence of seasonality in either month of birth or month of diagnosis overall or in any subgroups by age, sex, histology or immunophenotype. We did however find a significant (P = 0.01) February peak in month of birth for cases born before 1960 and a significant (P = 0.02) August peak in month of diagnosis for those diagnosed before 1962. Whilst these findings may be due to chance they are also consistent with changes over time in the seasonality of exposure, or immunological response, to a relevant infection. Changes in the seasonal variation in the fatality rate of a pre-leukaemic illness, such as pneumonia, could be another explanation.

Adolescent↗

PubMed2001

Mortality and cancer incidence in persons with Down's syndrome, their parents and siblings.

A cohort study of 1425 persons with Down's syndrome (DS), and of their parents (447 mothers, 435 fathers) and siblings (1176), was set up to investigate death rates from various causes and cancer incidence patterns. In individuals with DS the all-cause death rate was six times that of the national population (SMR = 622: 95% CI 559-693), the excess being attributable to many different causes. These included: leukaemia (SMR = 1304: 95% CI 651-2334); diabetes mellitus (SMR = 982: 95% CI 267-2515); Alzheimer's disease (SMR = 22028: 95% CI 7137-51326); epilepsy (SMR = 1727: 95% CI 744-3403); and congenital anomalies (SMR = 4987: 95% CI 4175-5955). The overall survival showed marked improvements for successive birth cohorts, particularly at young ages. For mothers and fathers of persons with DS, all-cause death rates were 20% lower than national rates and there were no significant excesses from any specific cause. For siblings, all-cause death rates were similar to national rates; the only condition with a significantly raised mortality ratio was colo-rectal cancer (SMR = 793: 95% CI 216-2031), but this may well be a chance finding.

Adolescent↗

PubMed2001

Mortality and cancer incidence in persons with numerical sex chromosome abnormalities: a cohort study.

Mortality and cancer incidence were assessed in a cohort of 1373 patients with numerical sex chromosome abnormalities diagnosed at three cytogenetics centres in Britain during 1959-90, and were compared with expectations from national rates. Four hundred patients with Turner's syndrome were followed, of whom 62 died, with a relative risk (RR) of death of 4.16 (95% confidence interval (CI) 3.22-5.39). Turner's syndrome patients had greatly raised risks of death from diseases of the nervous, cardiovascular, respiratory, digestive and genitourinary systems. One hundred and sixty three deaths occurred among 646 patients with Klinefelter's syndrome with a 47,XXY constitution, giving an RR of 1.63 (1.40-1.91). Mortality in these patients was significantly raised from diabetes and diseases of the cardiovascular, respiratory and digestive systems. There was also significantly increased mortality for patients with X polysomy (RR = 2.11 (1.43-3.02)) and Y polysomy (RR = 1.90 (1.20-2.85)), the former with significantly increased mortality from cardiovascular disease and the latter from respiratory disease. The only significantly raised risks of cancer incidence or mortality in the cohort were for lung cancer and breast cancer in patients with Klinefelter's syndrome with a 47,XXY constitution, and non-Hodgkin's lymphoma in men with more than three sex chromosomes.

Adolescent↗