PubMed HealthSearch

Biomedical subjects

J L Peacock

Publications and source records attributed to J L Peacock.

At least 19 recordsLinked to original sources

Who calls 999 and why? A survey of the emergency workload of the London Ambulance Service.

BACKGROUND: In 1996-97 there were 623,000 emergency (999) calls made to the London Ambulance Service (LAS) and this represents a 30% increase over the previous five years. The reasons for this increase, which is also observed nationally, remain unknown. It has been suggested that some callers may be using the 999 service "inappropriately" but no data are available from the ambulance service. OBJECTIVE: To describe the workload of the emergency ambulance service in London with specific reference to the nature and characteristics of 999 calls, to determine who dials 999 and why, and to establish the number and types of calls that could most appropriately be dealt with by other agencies. DESIGN: A one week census of all emergency calls responded to by the LAS. SETTING: Sixty eight LAS stations. METHODS: Collation of all routine LAS incident forms (LA4) including the classification of the crews' free text description of the incident. This was supplemented by a detailed workload questionnaire for 25% of calls. RESULTS: There were 10,921 calls responded to from 29 April to 5 May 1996. The census showed that the daily number of calls was highest on Saturday and lowest on Wednesday with about half being made during normal general practitioner (GP) working hours. Half of all calls were for women and one third were for people aged > or = 65. Accidents were the commonest type of incident (24%). The remainder comprised various medical conditions such as respiratory, cardiac, and obstetric problems. In 1.5% of calls there was no illness, injury, or assistance required and 5% were for "general assistance" and mostly concerned people aged > or = 65. The workload survey indicated that two thirds of incidents occurred at home and 70% of callers had not tried to contact a GP before dialing 999. In the professional opinion of the responding crew, 60% of calls required a 999 response, with the remainder thought more appropriately dealt with by other services such as primary care, psychiatric services, and social services. CONCLUSIONS: This study suggests that while the majority of 999 calls were "appropriate", part of the 999 workload could be dealt with by other services. More research is required to clarify why people contact the 999 service for non-emergency incidents and also to establish the views of GPs and other agencies as to the role and function of the IAS.

Emergency Medical Service Communication Systems

Maternal cotinine level during pregnancy and birthweight for gestational age.

BACKGROUND: Recent studies have found that cotinine is a better predictor of birthweight than the number of cigarettes smoked in pregnancy. In this paper we test this hypothesis and use cotinine to explore the effect of environmental tobacco smoke (ETS) on birthweight. METHODS: In all, 1254 white women were interviewed at booking, 28 and 36 weeks about the number and brand of cigarette smoked. Cotinine was assayed from blood samples taken on the day of interview. The outcome was birthweight for gestational age. RESULTS: There was good agreement between self-reported smoker/non-smoker status and maternal cotinine with 1.3% women mis-reported as non-smokers at booking, 0.6% and 1.8% mis-reported at 28 and 36 weeks respectively. Among smokers, cotinine was more closely related to birthweight than the number of cigarettes smoked at all three time points (r = -0.25 versus r = -0.16 at booking). A reduction in cotinine between booking and 28 weeks was associated with increased birthweight but the effect was not statistically significant. Among non-smokers the association between birthweight and cotinine was not statistically significant after adjusting for maternal height, parity, sex and gestational age. Difference in mean birthweight between non-smokers in the lower and upper quintiles of cotinine was 0.2% (95% CI: -2.4, 2.8). Pooling the results of 10 studies plus our own gave an estimated difference in mean birthweight between women unexposed and exposed to passive smoke of 31 g (95% CI: 19, 44). CONCLUSIONS: Cotinine is a better predictor of birthweight than the reported number of cigarettes smoked. If biochemical analysis is impossible, then self-reported smoking habit should be obtained prospectively using a structured approach. Any effect on birthweight of maternal passive smoking during pregnancy is small compared with the effects of maternal active smoking.

Adult

Relation of caffeine intake and blood caffeine concentrations during pregnancy to fetal growth: prospective population based study.

OBJECTIVES: To examine the association of plasma caffeine concentrations during pregnancy with fetal growth and to compare this with relations with reported caffeine intake. DESIGN: Prospective population based study. SETTING: District general hospital, inner London. SUBJECTS: Women booking for delivery between 1982 and 1984. Stored plasma was available for 1,500 women who had provided a blood sample on at least one occasion and for 640 women who had provided a sample on all three occasions (at booking, 28 weeks, and 36 weeks). MAIN OUTCOME MEASURE: Birth weight adjusted for gestational age, maternal height, parity, and sex of infant. The exposures of interest were reported caffeine consumption and blood caffeine concentration. Cigarette smoking was assessed by blood cotinine concentration. RESULTS: Caffeine intake showed no changes during pregnancy, but blood caffeine concentrations rose by 75%. Although caffeine intake increased steadily with increasing cotinine concentration above 15 ng/ml, blood caffeine concentrations fell. Caffeine consumption was inversely related to adjusted birth weight, the estimated effect being a 1.3% fall in birth weight for a 1,000 mg per week increase in intake (95% confidence interval 0.5% to 2.1%). The apparent caffeine effect was confined to cigarette smokers, among whom the estimated effect was-1.6%/1000 mg a week (-2.9% to -0.2%) after adjustment for cotinine and -1.3% (-2.7% to 0.1%) after further adjustment for social class and alcohol intake. Adjusted birth weight was unrelated to blood caffeine concentrations overall (P = 0.09, but a positive coefficient), after adjustment for cotinine (P = 0.73), or among current smokers (P = 0.45). CONCLUSIONS: Smokers consume more caffeine than non-smokers. Blood caffeine concentrations during pregnancy are not related to fetal growth, but caffeine intake is negatively associated with birth weight, with this effect being apparent only in smokers. The effect remains of borderline significance after adjustment for other factors. Prudent advice for pregnant women would be to reduce caffeine intake in conjunction with stopping smoking.

Beverages

Onset time of topical analgesia with EMLA 5%: no reduction with glyceryl trinitrate.

Many adults are distressed by painful investigations or treatment, including venepuncture. The early effects of Eutectic Mixture of Local Anaesthetics (EMLA) 5%, on relief of pinprick pain in the antecubital area was investigated and compared with EMLA plus glyceryl trinitrate and with a placebo cream in 100 patients. Topical analgesia after application of EMLA developed within 5 min in 69% and within 10 min in 83% of those tested, significantly different from placebo, (P = 0.01).

Adolescent

Acute effects of summer air pollution on respiratory function in primary school children in southern England.

BACKGROUND: There is growing concern about health effects of air pollution in the UK. Studies in the USA have reported adverse effects on lung function among children but no comparable studies have been published in the UK. This study investigates the relationship between daily changes in ambient air pollution and short term variations in lung function in a panel of school children. METHODS: One hundred and fifty four children aged 7-11 attending a primary school adjacent to a major motorway in Surrey, south-east England, were studied. Bellows spirometry was performed daily on 31 schooldays between 6 June and 21 July 1994. Levels of ozone, nitrogen dioxide, and particulates of less than 10 microns in diameter (PM10) were measured continuously at the school and the pollen count was measured six miles away. Relationships between daily changes in forced expiratory volume in 0.75 seconds (FEV0.75), forced vital capacity (FVC), the FEV0.75/FVC ratio and pollutants were analysed using separate autoregressive models for each child. A weighted average of the resulting slopes was then calculated. RESULTS: There was a significant inverse relationship between daily mean PM10 levels lagged one day and FVC, with a reduction in lung function of 1% (95% CI 0.3% to 2%) across the whole range of PM10 levels (20-150 micrograms/m3). The effect on FEV0.75 was similar (-0.5%) but was not significant when weighted by 1/SE2 (95% CI -1.2% to 0.2%). There was no effect of PM10 levels on the FEV0.75/FVC ratio. No significant association was seen between FEV0.75, FVC, or the FEV0.75/FVC ratio and either ozone or nitrogen dioxide levels. There was no evidence that wheezy children were more affected than healthy children. Pollen levels on the previous day had no effect on lung function and did not change the air pollution results. CONCLUSIONS: There is a very small, but statistically significant, adverse effect of airborne respirable particulate matter, measured as PM10, on lung function in this study group. There is no evidence for an inverse association of lung function with levels of ozone or NO2 measured on the previous day.

Air Pollutants

Preterm delivery: effects of socioeconomic factors, psychological stress, smoking, alcohol, and caffeine.

OBJECTIVE: To examine the relation between preterm birth and socioeconomic and psychological factors, smoking, and alcohol, and caffeine consumption. DESIGN: Prospective study of outcome of pregnancy. SETTING: District general hospital in inner London. PARTICIPANTS: 1860 consecutive white women booking for delivery; 1513 women studied after exclusion because of multiple pregnancy and diabetes, refusals, and loss to follow up. MEASUREMENTS: Gestational age was determined from ultrasound and maternal dates; preterm birth was defined as less than 37 completed weeks. Independent variables included smoking, alcohol and caffeine consumption, and a range of indicators of socioeconomic status and psychological stress. MAIN RESULTS: Unifactorial analyses showed that lower social class, less education, single marital status, low income, trouble with "nerves" and depression, help from professional agencies, and little contact with neighbours were all significantly associated with an increased risk of preterm birth. There were no apparent effects of smoking, alcohol, or caffeine on the length of gestation overall, although there was an association between smoking and delivery before 32 weeks. Cluster analysis indicated three subgroups of women delivering preterm: two predominantly of low social status and a third of older women with higher social status who did not smoke. Mean gestational age was highest in the third group. CONCLUSIONS: Adverse social circumstances are associated with preterm birth but smoking is not, apart from an association with very early births. This runs counter to findings for fetal growth (birth weight for gestational age) in this study, where a strong effect of smoking on fetal growth was observed but there was no evidence for any association with psychosocial factors.

Alcohol Drinking

Symptoms and health problems in pregnancy: their association with social factors, smoking, alcohol, caffeine and attitude to pregnancy.

This paper describes the prevalence and correlates of symptoms and health problems in pregnancy using data from a prospective population study in London. Data on the prevalence of 11 symptoms and 12 health problems were obtained at three points in pregnancy from a consecutive sample of 1513 white women. Relationships were examined between these symptoms and a range of psychosocial factors including social class, education, marital status, income, smoking, alcohol, caffeine, attitude to pregnancy and whether the pregnancy was planned. Most women reported nausea and breast tenderness in early pregnancy. Heartburn, backache, constipation and headaches were also common. The prevalence of symptoms tended to increase with gestation except for nausea and vomiting. Women with manual occupations, minimum education, low income, single marital status and unplanned pregnancy reported more of most symptoms except nausea which was associated with higher social status. A negative attitude to pregnancy was associated with more headaches but was unrelated to nausea. Women who smoked reported more 'nerves and depression' but less nausea. In general, nausea and vomiting showed a different pattern of associations from all other symptoms.

Alcohol Drinking

Importance of margin status in outcome of breast-conserving surgery for carcinoma.

BACKGROUND: The importance of margin status in breast-conserving therapy (BCT) for breast cancer remains unclear. We reviewed our experience with BCT to determine the risk of local recurrence as a function of margin status. METHODS: Stages I and II breast cancers treated with BCT between 1985 and 1990 were reviewed. Two hundred eleven patients were classified based on initial margin status: negative (more than 3 mm), close (3 mm or less), positive, or unknown. The incidence of reexcision and residual tumor is reported in each group. Patients with 36 months or more of follow-up (n = 183) were also stratified by final margin to examine rates of local recurrence and distant recurrence. RESULTS: Residual carcinoma was found in 0%, 24%, 44%, and 48% of the negative, close, positive, and unknown initial margin groups, respectively. The local recurrence rate was equivalent by Fisher exact test in patients with negative and close final margins (3%). The negative and close groups were not different by chi-squared analysis in terms of T stage, estrogen receptor status, and nodal status. CONCLUSIONS: Although one fourth of patients with close margins have residual tumor, recurrence rates are similar to those with negative margins. Reexcision of close margins is not necessary in patients who undergo BCT for carcinoma.

Breast Neoplasms

The effect of anxiety and depression during pregnancy on obstetric complications.

OBJECTIVE: To investigate the effects of anxiety and depression during pregnancy on obstetric complications using the data collected from the St George's Birthweight Study. DESIGN: Prospective population study. SETTING: District general hospital in inner London. SUBJECTS: A consecutive series of 1860 white women booking for delivery were approached. Of these, 136 refused and 209 failed to complete the study for other reasons, leaving a sample of 1515. MAIN OUTCOME MEASURE: Data were obtained by research interviewers at booking, 17, 28, and 36 weeks gestation and from the structured antenatal and obstetric record. The predictor variables were the anxiety and depression scores measured using the General Health Questionnaire. The outcome variables were five obstetric complications: preterm delivery; nonspontaneous onset of labour; major analgesia in the first and second stages of labour; and nonspontaneous vaginal deliveries. The possible confounding effects of 35 socio-economic, psychological and personal variables were investigated using logistic regression. RESULTS: The factors that had the strongest relation with the outcomes were parity and maternal age. Depression during pregnancy was unrelated to the obstetric complications. Anxiety was weakly related to analgesia/anaesthesia in the second stage of labour (P = 0.04). However, anxiety accounted for only 0.1% of the variance in use of major analgesia/anaesthesia. The most effective model, that for analgesia/anaesthesia in the first stage of labour, accounted for only 7.3% of the variance. CONCLUSIONS: In the general population of pregnant women, anxiety and depression during pregnancy, while undesirable in themselves, are of little importance in the evolution of obstetric complications.

Adolescent

Cancer cachexia is transmissible in plasma.

The cause of cancer cachexia is unclear. Tumors may be competing with the host for ingested nutrients or may be releasing some factor that actively inhibits energy utilization. To explore these questions, plasma was sterilely collected and pooled from 103 terminally cachectic Fischer 344 rats implanted with an experimental sarcoma. Control plasma was collected in similar fashion from 138 nontumor-bearing rats (NTBP). Plasma from tumor-bearing rats (TBP) or NTBP was continuously infused in a randomized, blinded fashion for 4 days into 20 normal rats. During infusion, food intake and nitrogen excretion were measured daily. At sacrifice, body weight and organ masses were determined. Rats receiving TBP demonstrated an immediate and profound anorexia compared with those receiving NTBP. Total food intake during treatment was 31.2 +/- 3.3 (g +/- SEM) in the TBP group versus 48.2 +/- 2.8 in the NTBP group (P less than 0.001 by t test). Likewise, the total decline in body weight was greater in the TBP group as compared with the NTBP group (-35.2 +/- 3.4 versus -14.6 +/- 4.0, P less than 0.001). Mean daily nitrogen balance during treatment was negative in the rats receiving TBP (-14.5 +/- 20.1 mg +/- SEM) while remaining highly positive in the rats receiving NTBP (110.7 +/- 19.3, P less than 0.002). Finally, cardiac and gastrocnemius muscle masses were decreased, while hepatic mass was unaffected. These data demonstrate that the syndrome of cancer-associated cachexia is transmissible in plasma and therefore may be mediated by a circulating molecule or molecules. Identification and purification of the molecule(s) responsible for this effect would have obvious clinical benefits.

Animals

Marital status: association with social and economic circumstances, psychological state and outcomes of pregnancy.

We examined the association of marital status with economic, social and psychological factors and with the outcomes of pregnancy (defined as onset of labour, type of delivery, live and still births and birthweight). The study population was 1431 white women consecutively booking for antenatal care. Birth registrations were inspected. Of 278 women who were unmarried during pregnancy, 61 per cent were cohabiting, 26 per cent were living with adults other than the father and 13 per cent were living alone. Compared with the married women, unmarried women overall were, on average, younger, less educated, of lower social class, in poorer economic circumstances, more dependent on state support and less satisfied with their living arrangements. Irrespective of age and social class, they were less likely to have planned the pregnancy, more likely to smoke and drink, to book later for antenatal care and to miss more appointments. In general, unmarried women were more likely to have some indication of depression and to experience more serious life events during the pregnancy. Controlling for age and social class, the categories 'married', 'cohabiting' and 'on their own' showed significant trends from best to worst. Those living with adults other than the father showed intermediate results. There were no significant effects of marital status, controlled for age and social class, and associated social, economic and psychological circumstances on outcomes of pregnancy. Forty-one per cent of births to women on their own, 35 per cent to women living with other adults and 11 per cent to women cohabiting during pregnancy were registered by only one parent.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent

Cigarette smoking and birthweight: type of cigarette smoked and a possible threshold effect.

The effects on birthweight of the number of cigarettes smoked and their tar, nicotine and carbon monoxide yields were investigated prospectively in 1309 pregnant women of whom 414 were smokers. Several approaches to modelling the effect of smoking were tried. These suggested that while both yield and quantity smoked were important, yield had the greatest effect. This led to an empirical approach whereby consistent smokers were divided into four categories according to whether they smoked a low or high quantity of cigarettes per day and whether they smoked low or high yield cigarettes. Using these four groups it emerged that women smoking a low quantity of low yield cigarettes had babies of a similar mean birthweight to those of non-smokers whereas those smoking a low quantity of high yield cigarettes had babies whose birthweight was reduced to the same degree (6% or more) as those of mothers who smoked higher quantities. This apparent threshold was estimated as 13 cigarettes/day and 15 mg/cigarette carbon monoxide. We conclude that brand smoked is at least as important as quantity and that in this population there is evidence for a threshold for tobacco smoke intake below which no discernible effect on birthweight is seen.

Birth Weight

The effects of smoking and drinking on the anthropometric measurements of neonates.

This study investigated the effects of smoking and alcohol consumption in pregnancy on length, head circumference, upper arm circumference and ponderal index, of neonates born to 1513 Caucasian women who delivered at St George's Hospital, south London. All measurements were adjusted for gestational age, maternal height, parity and sex of infant. Babies of smokers were shorter, had lower ponderal index and smaller upper arm circumference than those of non-smokers. After controlling for alcohol consumption, these differences remained (but with reduced statistical significance). There was no statistically significant difference in head circumference between smokers and non-smokers. Alcohol consumption at booking had no effect on growth measurements in non-smokers but had a significant, negative effect on all measurements in smokers. Drinking later in pregnancy had less effect. Alcohol appears to enhance the growth-retarding effect of smoking. It is suggested that both smoking and alcohol also have an inhibitory effect on fat deposition in babies, which contributes to the reduction in birthweight associated with smoking and drinking.

Alcohol Drinking

Effects on birthweight of alcohol and caffeine consumption in smoking women.

STUDY OBJECTIVE: Previous work found no effect on birthweight of alcohol and caffeine consumption in non-smokers but such an effect was found in smokers. This report investigates further the effects on birthweight of alcohol and caffeine at three stages of pregnancy in smoking women. DESIGN: This was a prospective population study. SETTING: District general hospital in inner London. PARTICIPANTS: Out of 1309 women who completed all pregnancy interviews, 895 were excluded because they did not smoke, leaving a sample of 414 smokers. MEASUREMENTS AND MAIN RESULTS: Number and brand of cigarettes smoked, and quantity of alcohol and caffeine consumed were obtained by interview at booking, 28, and 36 weeks gestation. Birthweight was corrected for gestation and adjusted for maternal height, sex of infant and parity. The effect on birthweight of alcohol consumption was not explained by the amount smoked in terms of quantity and yield. Similarly the effect of caffeine was independent of smoking. When alcohol, caffeine, and smoking were analysed together, alcohol and caffeine were both associated with reductions in birthweight. Alcohol was associated with a reduction of up to 8% after adjusting for tobacco and caffeine intake, and caffeine was associated with a reduction of up to 6.5% after adjusting for tobacco and alcohol intake. Women who at booking were heavy smokers (greater than or equal to 13 cigarettes/day or greater than or equal to 15 mg carbon monoxide/cigarette), heavy drinkers (greater than or equal to 100 g/week alcohol), and had high caffeine intake (greater than or equal to 2801 mg/week) had a predicted reduction in mean birthweight of 18% (95% CI 11% to 24%). CONCLUSIONS: It is well known that women who smoke in pregnancy have smaller babies than non-smokers. Our study suggests that if these women also drink alcohol and high quantities of caffeine then the risk of poor fetal growth is increased even further.

Alcohol Drinking

Nutrient intakes during pregnancy: observations on the influence of smoking and social class.

The influence of smoking and social class on dietary intake in pregnancy was investigated in a random sample of smokers (greater than or equal to 15 cigarettes/d) and nonsmokers. A total of 206 subjects (94 smokers and 112 nonsmokers) completed a 7-d weighed dietary intake at 28 wk gestation and 178 completed a second assessment at 36 wk. Nonsmokers had higher intakes of almost all nutrients than did smokers and the nutrient density of their diet was greater. Energy intake was nonsignificantly higher in nonsmokers. Women in higher social classes had the highest nutrient intakes. Smokers were shorter than nonsmokers and tended to be of lower social class. After maternal height and social class were controlled for, smoking had a significant effect on intake of many micronutrients. Dietary intake was reduced in late pregnancy, particularly in smokers. These data suggest that smokers in all social classes have a poorer quality of diet.

Adult