Prevention of brachial plexus injury-12 years of shoulder dystocia training: an interrupted time-series study.

OBJECTIVE: To investigate management and outcomes of incidences of shoulder dystocia in the 12 years following the introduction of an obstetric emergencies training programme. DESIGN: Interrupted time-series study comparing management and neonatal outcome of births complicated by shoulder dystocia over three 4-year periods: (i) Pre-training (1996-99), (ii) Early training (2001-04), and (iii) Late training (2009-12). SETTING: Southmead Hospital, Bristol, UK, with approximately 6000 births per annum. POPULATION: Infants and their mothers who experienced shoulder dystocia. METHOD: A bi-monthly multi-professional 1-day intrapartum emergencies training course, that included a 30-minute practical session on shoulder dystocia management, commenced in 2000. MAIN OUTCOMES: Neonatal morbidity (brachial plexus injury, humeral fracture, clavicular fracture, 5-minute Apgar score <7) and documented management of shoulder dystocia (resolution manoeuvres performed, traction applied, head-to-body delivery interval). RESULTS: Compliance with national guidance improved with continued training. At least one recognised resolution manoeuvre was used in 99.8% (561/562) of cases of shoulder dystocia in the late training period, demonstrating a continued improvement from 46.3% (150/324, P < 0.001) pre-training, and 92% (241/262, P < 0.001) in the early training period. In parallel there was reduction in the brachial plexus injury at birth (24/324 [7.4%, P < 0.01], pre-training, 6/262 [2.3%] early training, and 7/562 [1.3%] late training. CONCLUSIONS: There are significant benefits to long-term, embedded training programmes with improvements in both management and outcomes. A decade after the introduction of training there were no cases of brachial plexus injury lasting over 12 months in 562 cases of shoulder dystocia.

Association of diabetes with age-related macular degeneration in the EUREYE study.

OBJECTIVE: To examine the association between self-reported diabetes history and early or late age-related macular degeneration (AMD) in the European population. METHODS: Participants aged 65 years and over in the cross-sectional population-based EUREYE study underwent an eye examination including digital retinal photography. The images were graded at a single centre. A structured questionnaire was administered by trained field workers for putative risk factors for AMD including history of diabetes mellitus. Logistic regression models were used to examine the association between diabetes and stages of AMD, taking account of potential demographic, behavioural, dietary and medical (history of cardiovascular disease) confounders. MAIN OUTCOME MEASURES: Photographic images were graded according to the modified International Classification System for AMD and stratified into five exclusive stages from no signs of AMD (AMD stage 0), early AMD (Stages 1-3) and late AMD (Stage 4). Late AMD was subdivided in neovascular AMD (NV-AMD) or geographic atrophy (GA). RESULTS: Data on diabetes history and potential confounders were available in 2117 control subjects without AMD, 2182 with early AMD, 49 with GA and 101 with NV-AMD. Of all participants, 13.1% reported a history of diabetes. After adjusting for potential confounders, subjects with neovascular AMD compared with controls had increased odds for diabetes (odds ratio 1.81; 95% confidence interval, 1.10 to 2.98, p = 0.02). Subjects with AMD grades 1 to 3 or GA had no increased odds for diabetes compared with those without AMD. CONCLUSIONS: In the EUREYE study, after multiple adjustments, positive association of diabetes mellitus with neovascular AMD was found. The hypothesis that diabetes is associated with neovascular AMD but not with geographic atrophy may suggest a different pathogenesis of the two advanced forms of the disease and needs to be further evaluated.

A re-evaluation of the impact of temperature and climate change on foodborne illness.

The effects of temperature on reported cases of a number of foodborne illnesses in England and Wales were investigated. We also explored whether the impact of temperature had changed over time. Food poisoning, campylobacteriosis, salmonellosis, Salmonella Typhimurium infections and Salmonella Enteritidis infections were positively associated (P<0.01) with temperature in the current and previous week. Only food poisoning, salmonellosis and S. Typhimurium infections were associated with temperature 2-5 weeks previously (P<0.01). There were significant reductions also in the impact of temperature on foodborne illnesses over time. This applies to temperature in the current and previous week for all illness types (P<0.01) except S. Enteritidis infection (P=0.079). Temperature 2-5 weeks previously diminished in importance for food poisoning and S. Typhimurium infection (P<0.001). The results are consistent with reduced pathogen concentrations in food and improved food hygiene over time. These adaptations to temperature imply that current estimates of how climate change may alter foodborne illness burden are overly pessimistic.

Cigarette smoking and age-related macular degeneration in the EUREYE Study.

OBJECTIVE: To examine the association between cigarette smoking and age-related maculopathy (ARM) including age-related macular degeneration (AMD) in the European population. DESIGN: Cross-sectional study. PARTICIPANTS: Four thousand seven hundred fifty randomly sampled > or =65-year-olds from 7 study centers across Europe (Norway, Estonia, United Kingdom, France, Italy, Greece, and Spain). METHODS: Participants underwent an eye examination and digital retinal photography. The images were graded at a single center. Smoking history was ascertained by a structured questionnaire administered by trained fieldworkers. Multinomial and binary logistic regressions were used to examine the association between smoking history and ARM grade and type of AMD, taking account of potential confounders and the multicenter study design. MAIN OUTCOME MEASURES: Photographic images were graded according to the International Classification System for ARM and stratified using the Rotterdam staging system into 5 exclusive stages (ARM 0-3 and ARM 4, also known as AMD). Age-related macular degeneration also was classified as neovascular AMD or geographic atrophy (GA). RESULTS: One hundred fifty-eight cases were categorized as AMD (109 neovascular AMD and 49 GA); 2260 had no signs of ARM (ARM 0). Current smokers had increased odds of neovascular AMD (odds ratio [OR], 2.6; 95% confidence interval [CI], 1.4-4.8) or GA (OR, 4.8; 95% CI, 2.1-11.1), whereas for ex-smokers the odds were around 1.7. Compared with people with unilateral AMD, those with bilateral AMD were more likely to have a history of heavy smoking in the previous 25 years (OR, 5.1; 95% CI, 1.3-20.0). The attributable fraction for AMD due to smoking was 27% (95% CI, 19%-33%). There was no consistent association with ARM grades 1 to 3 and smoking. CONCLUSIONS: These findings highlight the need for increasing public awareness of the risks associated with smoking and the benefit of quitting smoking. Patients with unilateral disease who are current smokers should be advised of the risk of second-eye disease.

Environmental temperatures and the incidence of food poisoning in England and Wales.

The incidence of food poisoning in England and Wales has been increasing for many years and it is now a major public health problem. Superimposed on this general rising trend is a well-established tendency for the number of cases of food poisoning to rise during the summer when warm weather favours the multiplication of pathogenic micro-organisms. This paper shows that weekly notifications of food poisoning in England and Wales are strongly associated with environmental temperatures, but that there are some important time lags in this relationship. The number of cases of food poisoning in a given week was only weakly correlated with the temperature of that week and the one preceding it. This suggests that factors operating close to the point of consumption within or outside the home are not the principal cause of the rise in food poisoning associated with warm summer conditions. There was a much stronger association with temperatures 2-5 weeks earlier, pointing to the importance of factors operating earlier in the food production or distribution system. The results of this study suggest that the food poisoning problem requires action by food producers and distributors as well as by consumers.

Geoepidemiology of systemic vasculitis: comparison of the incidence in two regions of Europe.

OBJECTIVE: The aetiopathogenesis of the primary systemic vasculitides (PSV) is unknown but includes both environmental and genetic factors. The development of classification criteria/definitions for PSV allows comparison of the epidemiology between different regions. METHODS: The same methods and the American College of Rheumatology (1990) criteria or Chapel Hill definitions were used to compare the epidemiology of Wegener's granulomatosis, Churg-Strauss syndrome, microscopic polyangiitis, and polyarteritis nodosa in Norwich (east England population 413 500) and Lugo (northwest Spain population 204 100). Patients with PSV were identified between 1 January 1988 and 31 December 1998. RESULTS: Overall, the incidence of PSV in adults was almost equal in Norwich (18.9/million) and Spain (18.3/million). The incidence of Wegener's granulomatosis in Norwich (10.6/million) was greater than in Spain (4.9/million). There was a marked age-specific increase in incidence in Norwich with a peak age 65-74 years (52.9/million), but a virtually equal age distribution between ages 45 and 74 in Lugo (34.1/million). There was no significant increase with time in either population, or evidence of cyclical changes in incidence. CONCLUSION: These data support the suggestion that environmental factors may be important in the pathogenesis of PSV.

Epidemiology of systemic vasculitis: a ten-year study in the United Kingdom.

OBJECTIVE: To describe the epidemiology of the primary systemic vasculitides (PSV; Wegener's granulomatosis, Churg-Strauss syndrome, microscopic polyangiitis, polyarteritis nodosa) in a well-defined population over a 10-year period. METHODS: An inception cohort of patients from the Norwich Health Authority (NHA) who were >15 years of age and had PSV first diagnosed between January 1, 1988 and December 31, 1997 was collected. Incidence rates were adjusted for age and sex to the 1992 population. The prevalence of PSV in this cohort was estimated on December 31, 1997. Patients were classified according to the American College of Rheumatology 1990 vasculitis criteria and the Chapel Hill Consensus definitions. RESULTS: Eighty-two NHA residents fulfilled the inclusion criteria. There were 47 men and 35 women, with a mean age of 62.9 years (median 65.0 years). The overall annual incidence of PSV among NHA residents was 19.8/million (95% confidence interval [95% CI] 15.8-24.6). The point prevalence on December 31, 1997 was 144.5/million (95% CI 110.4-185.3). PSV was more common in males (23.5/million; 95% CI 17.3-31.3) than females (16.4/million; 95% CI 11.4-22.8). The age- and sex-specific incidence showed a clear increase with age, with an overall peak in the 65-74 year age group (60.1/million). CONCLUSION: In our study population, the annual incidence of PSV is slowly increasing with time and the incidence is greatest in the elderly.

Frequencies of hprt(-) mutations and bcl-2 translocations in circulating human lymphocytes are correlated with United Kingdom sunlight records.

Between 1983 and 1995 we have monitored human populations for evidence of exposure to environmental mutagens, taking blood samples to measure hprt(-) mutant frequency in T cells and more recently bcl-2 t(14:18) translocation frequency in B cells. We have now analysed data from 785 assays on 448 blood samples from 308 normal subjects and find that there is a highly significant statistical correlation between hprt(-) mutant frequency and the sunlight record for the 3 weeks prior to taking the blood sample. We discuss the weaknesses in retrospective studies of this nature and the possibility of spurious epidemiological correlations that may result. More controlled experiments can be envisaged that would give a firmer basis to the statistical associations observed. hprt(-) mutations in T cells show little evidence of a UV fingerprint, so that the correlation may be due to immunomodulation rather than mutation. We also find a correlation between the sunlight record and bcl-2 translocation. This translocation is found at a low frequency in the B cells of many normal subjects and is the commonest translocation observed in non-Hodgkin's lymphoma. Our results strengthen the case for a link between sunlight and this increasingly common cancer.

Effects of distances to hospital and GP surgery on hospital inpatient episodes, controlling for needs and provision.

Age and sex adjusted inpatient episode ratios were calculated from hospital records over a two year period for 555 census wards in Cambridgeshire, Norfolk and Suffolk, UK. Hospital episodes were divided into acute, psychiatric and geriatric specialties, and elective and emergency acute admissions were distinguished. Variations in inpatient episode ratios between wards were compared with census indicators of the 'needs' of local populations for inpatient services, measures of the local provision of hospital and other related services, and measures of the distance to the nearest general practitioner surgery and the distance to the nearest hospital. Hospital episodes were found to be strongly related to both distance measures, but the associations were partially explained by a tendency for the health status of local populations (measured by the needs indicators) to be worst in urban areas close to health services. Including needs and provision variables together with the distance variables explained most of the variations in age and sex adjusted inpatient ratios for small areas. Needs were the most important determinants of emergency acute and psychiatric inpatient rates, but service provision was more important for elective acute and geriatric inpatients. Controlling for needs and provision, distance to hospital produced 17% reduction in acute episodes, 37% reduction in psychiatric episodes and 23% reduction in geriatric episodes over the range of distances observed. Distance to nearest GP surgery reduced elective acute episodes by up to 15% after controlling for confounders. These results demonstrate that the NHS is falling short of its aim to provide fair access to services irrespective of geography, and new policies will be required if geographical inequities are to be reduced.

Health service accessibility and deaths from asthma.

BACKGROUND: Good access to health services may be important for effective asthma management amongst patients, thus preventing unnecessary deaths. In a previous study, we found elevated levels of asthma mortality in English local authority districts with poor access to acute hospitals. Here, the relationship between asthma mortality and access to primary and secondary services within the rural region of East Anglia is examined. METHODS: A geographically based descriptive study, within 536 electoral wards in the region of East Anglia, England. Regression analysis was used to examine the relationship between health service accessibility, and mortality from asthma during the period January 1985 to December 1995. RESULTS: After controlling for confounding factors, there was a significant tendency for asthma mortality to increase with travel time to hospital, with a relative risk of 1.07 for each 10-minute increase in journey time (P = 0.04). There was no consistent trend for mortality to increase with travel time to general practitioner surgeries. CONCLUSIONS: The results of this study support the conclusions of earlier work that inaccessibility of acute hospital services may increase the risk of asthma mortality. The provision of good access to these facilities may be one factor in reducing the burden of avoidable deaths from asthma.

Possible effects of sunlight on human lymphocytes.

The human population is exposed to both the ultraviolet A (UVA) and B (UVB) regions of the solar spectrum. UVB induces mainly dipyrimidine photoproducts in DNA by a direct photochemical mechanism, whereas UVA is absorbed by other cellular constituents and induces mainly oxidative damage indirectly. The proportions of the different dipyrimidine photoproducts, and the ratio of dipyrimidine to oxidative damage depend on the exact spectral output of a UV source. Irradiation of human epidermal keratinocytes induces release of cytokines, with cyclobutane pyrimidine dimers playing a significant role in the process. These cytokines may then modulate the activity of cells of the immune system. Freshly isolated human lymphocytes are exquisitely sensitive to UVB irradiation, because of their low deoxyribonucleotide pools. They also have a separate defect in removal of cyclobutane pyrimidine dimers from their DNA. We have observed that frequencies of mutations at the hprt locus in human T-lymphocytes and translocations involving the bcl2 locus in B-lymphocytes appear to be associated with sunlight levels over the period before the blood sample was taken. This may be an indirect cytokine-mediated effect, and may be relevant to the possible link between non-Hodgkin's lymphoma and sunlight. On the other hand, sunlight can have beneficial effects, and may protect against autoimmune diseases including type I diabetes and multiple sclerosis.

Accessibility and health service utilization for asthma in Norfolk, England.

BACKGROUND: Good access to health services may be important for effective asthma management amongst patients. Previously, we found elevated asthma mortality in parts of England with poor access to acute hospitals. A possible explanation is that barriers of access to care may lead to residents of more remote areas having a lower propensity to utilize health services, with the result that their asthma is poorly controlled. Here, we examine the relationship between utilization and the geographical accessibility of health services amongst self-reported asthmatics in a rural county of England. METHODS: The study involved analysis by logistic regression of questionnaire responses from a 10 per cent population sample of 9764 adults aged between 20 and 44 years, and resident within the catchment area of Norwich Health Authority. RESULTS: Utilization behaviour was associated with the smoking status of respondents, and levels of car ownership in their ward of residence. After controlling for these factors, respondents reporting asthma were less likely to have ever visited a general practitioner if they lived outside a settlement containing a surgery (odds ratio (OR) 3.07, 95 per cent confidence interval (CI) 1.11-8.48, p = 0.03), and the likelihood of consultation declined with distance from a surgery (OR for a 1 minute increase in travel time 0.79, 95 per cent CI 0.66-0.94, p < 0.01). Those living further from an acute hospital unit were also less likely to have consulted a hospital doctor in the previous 12 months (OR for a 1 minute increase in travel time 0.95, 95 per cent CI 0.9-0.99, p = 0.01). CONCLUSIONS: Our finding of lower levels of health service utilization amongst some self-reported asthmatics living further from health facilities suggests that the condition of some individuals might be poorly treated, which could increase the risk of fatality.

Tuberculosis mortality in England and Wales during 1982-1992: its association with poverty, ethnicity and AIDS.

This paper seeks to establish the strength of association between contemporary tuberculosis (TB) in England and Wales and several potential aetiological factors. It presents an ecological analysis of standardised annual TB mortality rates for the 403 local authority districts between 1982 and 1992, disaggregated by age and sex. Social, demographic and ethnicity measures from the 1981 and 1991 censuses and standardised annual AIDS-related mortality rates for young men are used to calculate Poisson regression models. A strong association was found between all TB mortality groups and overcrowding at the household level. For women, no other measures improved the explanatory power of the models. In multiple regressions, both poverty and AIDS-related mortality explained additional variation in the model for younger men. The link between ethnicity and tuberculosis notifications was not reflected in this analysis of mortality. For all groups no evidence of a positive relationship with ethnicity was found, once overcrowding had been accounted for. The significance of household as opposed to district level crowding suggests that prolonged contact is required for disease transmission. Regression analysis indicates that it is the overcrowding and poverty among ethnic populations that is significant for their tuberculosis mortality. The fact that the relationship between AIDS and TB is confined to the group most typical of AIDS patients provides evidence that AIDS has little influence on the level of tuberculosis mortality in the wider population. Explanations for the observed relationship include preferential certification, migration for treatment and shortcomings in health care provision.

Multi-level modelling of geographically aggregated health data: a case study on malignant melanoma mortality and UV exposure in the European Community.

A multi-level modelling approach is used to examine the variance in mortality rates from malignant melanoma at different geographical scales within nine European nations with reference to exposure to ultraviolet light (UVB). For males and females, the greatest variations in the relationship between UVB exposure and mortality are seen between nations, rather than regions and sub-regions within nations. This suggests that factors and characteristics acting at a national scale, such as genetic and behavioural differences, are of importance. Multi-level modelling is used to show how a previous suggestion of a quadratic association between UVB exposure and malignant melanoma across Europe is unlikely to be true. The general usefulness of multi-level modelling in the analysis of disease data which is structured in a hierarchy is discussed, with particular reference to geographical analyses of small area data.

Mortality from non-Hodgkin lymphoma and UV exposure in the European Community.

There has been a large, unexplained rise in the incidence of non-Hodgkin's lymphoma (NHL) in many countries. It has been hypothesised that increased exposure to solar ultraviolet (UV) radiation may have been a factor in this increase. The hypothesis that exposure to ultraviolet radiation is a factor in NHL can be tested by examining whether geographical variations in UV and in the incidence of the disease are positively correlated. Previous studies have given mixed results but some of these have failed to take into account confounding by socio-economic factors and the multilevel structure of data derived from several different countries. It was therefore decided to carry out a study using data on NHL mortality for the period 1971-80 for level II administrative units in 9 countries in the European Community. Estimated levels of solar UV and per capita GDP were also derived. Poisson regression models of the relationship between NHL mortality, UV and per capita GDP, taking into account the multilevel structure of the data, were fitted using the MLn package. Simple models that did not adjust for the effects of variations in per capita GDP or account adequately for the structure of the data produced apparent negative or quadratic associations between NHL and UV. However, further models show that there is a highly significant positive association between NHL and per capita GDP. Once this is included in the fixed and random parts of the multilevel model the association between NHL and UV becomes positive although non-significant (p = 0.081) at the conventional 0.05 level. These results underline the need to control for socio-economic factors and to take into account the multilevel structure of the data. Studies using international data that do not do this run the risk of producing misleading results.

Effect of labour market conditions on reporting of limiting long-term illness and permanent sickness in England and Wales.

STUDY OBJECTIVE: To identify any bias in the reporting of limiting long term illness and permanent sickness due to labour market conditions, and show the absence of the effect in mortality rates. DESIGN: A geographically based study using data from the 1991 census. Standardised ratios for mortality and long term illness in people aged 0-64 years and permanent sickness in people of working age were compared with Carstairs deprivation scores in multilevel models which separated the effects operating at three geographical scales: census wards, travel to work areas, and standard regions. Holding ward and regional effects constant, variations between travel to work areas were compared with long term unemployment rates. SETTING: Altogether 8690 wards and 262 travel to work areas in England and Wales. MAIN RESULTS: Variations in mortality, limiting long term illness, and permanent sickness were related to Carstairs deprivation scores and standard region. With these relationships controlled, limiting long term illness and permanent sickness were significantly related to long term unemployment levels in travel to work areas, but mortality was not affected. Self reported morbidity was more sensitive to variations in long term unemployment rates in conditions of high social deprivation than in affluent populations. CONCLUSIONS: Limiting long term illness and permanent sickness measures may reflect a tendency for higher positive response in difficult labour market conditions. For average social deprivation conditions, standardised limiting long term illness for people aged 0-64 years was 20% higher in travel to work areas where employment prospects were relatively poor compared with areas with relatively good employment prospects. This casts doubt on the use of limiting long term illness as an indicator of objective health care needs for resource allocation purposes at national level.

A multilevel model of sudden infant death syndrome in England and Wales.

The relationship between migration and sudden infant death syndrome (SIDS) in England and Wales is analyzed using official data for the period 1979-1983. "In this paper, multilevel modelling is used to examine the variability in SIDS deaths at different geographical scales, namely district, county, and regional levels. Given the population-mixing hypothesis, it is possible that high levels of population mixing in one district will have an effect on the spread of infections in an adjacent district, and the rates for individual districts will not be spatially independent of each other. Factors such as climate varying at regional scale may also be important. A log-linear multilevel model is developed to examine these issues, and the discussion focuses on the methodological issues raised by the analysis such as appropriate multilevel structure, methods of estimation, dispersion of residuals, and significance of parameter estimates."

Health service accessibility and deaths from asthma in 401 local authority districts in England and Wales, 1988-92.

BACKGROUND: The possible contribution of health service accessibility to asthma mortality has not previously been studied in the UK. METHODS: Using regression analysis, the relationship between geographical isolation from large acute hospital services and mortality from asthma for 401 local authority districts in England and Wales was examined for the period 1988-92. RESULTS: Asthma mortality was found to be strongly associated with the proportion of district households where the head was of social class 4 or 5 (adjusted relative risk 1.61, 95% confidence interval (CI) 1.12 to 2.33), and the proportion of households without access to a car (adjusted relative risk 1.59, 95% CI 0.97 to 2.62). After controlling for these factors, there was a tendency for mortality to rise with increasing distance from hospital, with a relative risk of 1.01 for an increase in distance of one kilometre (95% CI 1.00 to 1.02). CONCLUSIONS: The findings suggest that problems of accessibility of care may mean that the control of asthma amongst sufferers living in districts most remote from major health service units might be less than optimal, and this could result in a number of potentially avoidable deaths.

Incidence of malignant melanoma of the skin in Norway, 1955-1989: associations with solar ultraviolet radiation, income and holidays abroad.

BACKGROUND: Norway has the highest incidence of melanoma in Europe. This study analyses geographical variations in melanoma incidence within Norway and their association with possible aetiological factors. METHODS: Data on melanoma incidence from the Norwegian Cancer Registry were used to calculate standardized incidence ratios (SIR) for the 19 counties in Norway for each 5-year period from 1955 to 1989. Multiple regression analysis was used to examine the associations between these SIR and local UVB levels, holidays abroad and income. Similar methods were also used to analyse changes in SIR between 1955-1969 and 1985-1989. RESULTS: There was a highly significant association between melanoma incidence and UVB in each of the time periods studied. Income showed a significant positive association in the 1960s and early 1970s but not later. Foreign holidays showed a significant positive association in the 1980s, but not earlier. Changes in melanoma SIR between 1955-1969 and 1985-1989 were significantly positively associated with holidays abroad and negatively with income levels. CONCLUSIONS: Melanoma incidence in Norway is closely related to local levels of UVB radiation independently of other factors suggesting that local exposures carry significant risk. Risks would probably increase if ozone depletion led to enhanced UVB flux (estimated as 1.6% rise in incidence for each 1% increase in UVB). By the end of the study period income was no longer a significant factor but holidays abroad had started to have a detectable effect on melanoma incidence.