Nigel Smeeton

Epidemiological study of Guillain-Barré syndrome in south east England

OBJECTIVES To determine the incidence, treatment, and outcome of Guillain-Barré syndrome in south east England. METHODS Patients presenting with confirmed Guillain-Barré syndrome between 1 July 1993 and 30 June 1994 were recruited via a voluntary reporting scheme coordinated by the British Neurological Surveillance Unit, hospital activity data collected from acute admitting hospitals within the South East and South West Thames Regional Health Authorities, death certificates, and a contemporary research study of Guillain-Barré syndrome and Campylobacter jejuni infection. All patients were followed up for one year to determine outcome. RESULTS Seventy nine patients were recruited, 35 (44%) male, 44 (56%) female, including three children (two boys, one girl). The crude (95% confidence interval (95% CI)) annual incidence was 1.2 (0.9–1.4) cases/100 000 population and 1.5 (1.3–1.8)/100 000 when adjusted for undetected cases. Twenty (25%) patients required ventilation for an average (SD) of 42 (64) days. Thirty six (46%) patients received intravenous human immunoglobulin, five (6%) received plasma exchange, 11 (14%) both treatments, three (4%) steroids, and 25 (32%) no immunomodulatory treatment. One year later, six patients (8%) had died, all of whom were older than 60, three (4%) remained bedbound or ventilator dependent, seven (9%) were unable to walk unaided, 14 (17%) were unable to run, and 49 (62%) had made a complete or almost complete recovery. Increasing age was significantly associated with a poorer outcome at one year. CONCLUSIONS Despite the frequent use of modern immunomodulatory treatments Guillain-Barré syndrome still carries considerable morbidity and mortality.

A randomised controlled trial comparing two schedules of antenatal visits: the antenatal care project.

Abstract Objective: To compare the clinical and psychosocial effectiveness of the traditional British antenatal visit schedule (traditional care) with a reduced schedule of visits (new style care) for low risk women, together with maternal and professional satisfaction with care. Design: Randomised controlled trial. Setting: Places in south east London providing antenatal care for women receiving shared care and planning to deliver in one of three hospitals or at home. Subjects: 2794 women at low risk fulfilling the trials inclusion criteria between June 1993 and July 1994. Main outcome measures: Measures of fetal and maternal morbidity, health service use, psychosocial outcomes, and maternal and professional satisfaction. Results: Pregnant women allocated to new style care had fewer day admissions (0.8 v 1.0; P=0.002) and ultrasound scans (1.6 v 1.7; P=0.003) and were less often suspected of carrying fetuses that were small for gestational age (odds ration 0.73; 95% confidence interval 0.54 to 0.99). They also had some poorer psychosocial outcomes: for example, they were more worried about fetal wellbeing antenatally and coping with the baby postnatally, and they had more negative attitudes to their babies, both in pregnancy and postnatally. These women were also more dissatisfied with the number of visits they received (odds ratio 2.50; 2.00 to 3.11). Conclusions: Patterns of antenatal care involving fewer routine visits for women at low risk may lead to reduced psychosocial effectiveness and dissatisfaction with frequency of visits. The number of antenatal day admissions and ultrasound scans performed may also be reduced. For the variables reported, the visit schedules studied are similar in their clinical effectiveness. Uncertainty remains as to the clinical effectiveness of reduced visit schedules for rare pregnancy problems. Key messages Key messages Women offered a reduced schedule of antenatal visits had a similar rate of caesarean sections for pregnancy related hypertensive disorders Women having fewer antenatal visits had fewer ultrasound scans and fewer antenatal day admissions Fewer antenatal visits may lead to poorer psychosocial outcomes and greater dissatisfaction among women More flexible approaches to the provision of psychosocial support and the reassurance of women about fetal wellbeing may be needed if reduced schedules of antenatal visits are to be introduced

QT interval in anorexia nervosa.

OBJECTIVES--To determine the incidence of a long QT interval as a marker for sudden death in patients with anorexia nervosa and to assess the effect of refeeding. To define a long QT interval by linear regression analysis and estimation of the upper limit of the confidence interval (95% CI) and to compare this with the commonly used Bazett rate correction formula. DESIGN--Prospective case control study. SETTING--Tertiary referral unit for eating disorders. SUBJECTS--41 consecutive patients with anorexia nervosa admitted over an 18 month period. 28 age and sex matched normal controls. MAIN OUTCOME MEASURES--maximum QT interval measured on 12 lead electrocardiograms. RESULTS--43.6% of the variability in the QT interval was explained by heart rate alone (p < 0.00001) and group analysis contributed a further 5.9% (p = 0.004). In 6 (15%) patients the QT interval was above the upper limit of the 95% CI for the prediction based on the control equation (NS). Two patients died suddenly; both had a QT interval at or above the upper limit of the 95% CI. In patients who reached their target weights the QT interval was significantly shorter (median 9.8 ms; p = 0.04) relative to the upper limit of the 60% CI of the control regression line, which best discriminated between patients and controls. The median Bazett rate corrected QT interval (QTc) in patients and controls was 435 v 405 ms.s-1/2 (p = 0.0004), and before and after refeeding it was 435 v 432 ms.s1/2 (NS). In 14(34%) patients and three (11%) controls the QTc was > 440 ms.s-1/2 (p = 0.053). CONCLUSIONS--The QT interval was longer in patients with anorexia nervosa than in age and sex matched controls, and there was a significant tendency to reversion to normal after refeeding. The Bazett rate correction formula overestimated the number of patients with QT prolongation and also did not show an improvement with refeeding.

Hip dysplasia in bilateral cerebral palsy: incidence and natural history in children aged 18 months to 5 years

Children with bilateral cerebral palsy (CP) born during 1989 to 1992 (n=346) to a geographically defined population were ascertained and followed up to age 5 years. The aims of the study were to monitor hip development by serial X-rays; to record gross locomotor development, aspects of physical management, and any hip-related orthotics or surgery; to learn more of the natural history of hip development in this condition; and to provide guidelines for a surveillance protocol for those clinically managing children with bilateral CP. Children were X-rayed at 18, 24, 30, 48, and 60 months. X-rays were taken in a standardized position and measured to record migration percentage, acetabular index, Sharps angle, and Smiths diaphyseal ratios. Relationships between the measures were investigated and a natural history of the childrens hip development suggested. At as early as 18 months, migration percentages were significantly greater than in the normally developing population, although no measured CP factor could be identified to be the cause of this early change. Two possible factors affecting early hip development are described, neither of which is clinically apparent: the first separates the bilateral CP population as a whole from the normal population; but there is an additional presdisposing factor affecting some children only which in the presence of the motor disorder, has a significant influence on early hip development and subsequent dysplasia. The study confirms that, when measured correctly, migration percentage is the best guide to hip surveillance and the need for treatment. It is suggested that all children with bilateral CP should be X-rayed in a standardized position at 30 months (corrected for gestational age).

Atrioventricular septal defects diagnosed in fetal life: Associated cardiac and extra-cardiac abnormalities and outcome

OBJECTIVES We sought to establish the outlook for fetuses diagnosed with atrioventricular septal defect (AVSD) prenatally and its relation to additional cardiac, extracardiac and chromosomal abnormalities. BACKGROUND Prediction of likely outcome of AVSD presenting prenatally is complicated by the wide variation in associated features. METHODS Computerized records from 14,726 pregnancies referred to a fetal cardiology center were reviewed retrospectively. Pathological reports, postnatal records, follow-up inquiries and review of echocardiographic video recordings supplemented analysis of the records for all those with AVSD. RESULTS Atrioventricular septal defect was confirmed in 301 fetuses. Eighty-six (39%) of the 218 with known karyotype had trisomy 21, and 21/218 (10%) had other chromosome abnormalities. Right isomerism occurred in 37/301 (12%) fetuses, left isomerism in 62 (20%), mirror image atrial arrangement in 2 (1%), and 200 (67%) had usual arrangement. Atrioventricular septal defect occurred without any other intracardiac abnormality in 155 fetuses (51%). Extracardiac abnormalities and nonkaryotypic syndromes were evident in 40 fetuses (13%, confidence interval [CI] 9.5-17.1%). Uncomplicated cardiac anatomy was significantly associated with the presence of karyotype abnormality (p < 0.0001). Parents opted for termination of pregnancy in 175/298 (58.5%). For the continuing pregnancies, Kaplan-Meier estimates for live birth, survival past the neonatal period and survival to three years were 82% (CI 75.3-88.9%), 55% (CI 46.0%-0/64.3%) and 38% (CI 27.1-48.6%), respectively. Fetal hydrops and earlier year of diagnosis were independent variables with adverse influence on survival. CONCLUSIONS Despite some improvements in the outlook for AVSD diagnosed prenatally, the overall prognosis remains considerably poorer than that implied from surgical series. The detection of associated cardiac and extracardiac abnormalities is important in order to give the best indication of the likely outcome when counseling parents.

Long axis excursion in aortic stenosis

OBJECTIVES To examine long axis excursion in patients with all grades of aortic stenosis and preserved transverse systolic function, and to compare long axis excursion in symptomatic with that in asymptomatic severe aortic stenosis. DESIGN Prospective comparative study. SETTING Regional cardiothoracic centre. PATIENTS 78 patients with all grades of aortic stenosis and normal fractional shortening and ejection fraction were studied. There were two comparison groups, 10 age matched normal subjects and 14 patients with aortic stenosis and fractional shortening < 26%. METHODS Aortic valve function and left ventricular mass were assessed echocardiographically. M mode measurements of long axis excursion at the septal and lateral sides of the mitral annulus were taken. RESULTS There were significant differences between the groups in long axis excursion at both the septal (p < 0.0001) and lateral sides of the mitral annulus (p = 0.002 by analysis of variance). Long axis excursion was independently related to both left ventricular mass index (p = 0.001) and the grade of aortic stenosis (p = 0.002). Comparing patients with severe aortic stenosis with and without symptoms, there were significant differences in effective orifice area (p = 0.02 ) and long axis excursion at the lateral side of the mitral annulus (p = 0.04), but not in fractional shortening, ejection fraction, or peak or mean pressure difference. CONCLUSION In patients with aortic stenosis, long axis excursion is reduced even in the presence of normal fractional shortening or ejection fraction. It is lower in patients with symptomatic compared with asymptomatic severe aortic stenosis and may be of use in predicting the onset of symptoms.

Survival differences after stroke in a multiethnic population: follow-up study with the south London stroke register

Abstract Objectives To identify ethnic differences in survival after stroke and examine the factors that influence survival. Design Population based stroke register with follow-up. Settings South London stroke register. Participants 2321 patients with first stroke registered between January 1995 and December 2002. Main outcome measures Sociodemographic factors, risk factors for stroke and their management, severity of stroke, and acute service provision factors. Survival analysis with Kaplan-Meier curves, log rank test, and Coxs proportional hazard model with stratification. Results In univariable analyses of survival, outcome was better for black people than white people (median 33.7 v 20.0 months). After stratification by socioeconomic status, type of stroke, and Glasgow coma score, and adjustment for other potential confounders, being black was generally associated with better survival, taking into account the interaction between ethnicity and age, and ethnicity and prior Barthel score. Of the risk factors for stroke considered, current smoking (hazard ratio 1.21, 95% confidence interval 1.01 to 1.45, P = 0.044), untreated atrial fibrillation (1.36, 1.08 to 1.72, P = 0.009), untreated diabetes (1.53, 1.05 to 2.22, P = 0.027), and treated diabetes (1.61, 1.27 to 2.03, P < 0.001) were associated with reduced survival. Conclusion In general, black patients in a south London population with first ever stroke are more likely to survive than white patients, the exceptions being in those aged < 65 and those with a prior Barthel score < 15. Some pre-stroke risk factors that have the potential to be modified, including the appropriate treatment of existing health problems, have a strong impact on survival.

Oral surgery: Factors predictive of difficulty of mandibular third molar surgery

Aim Historically the difficulty of third molar surgery has been judged using radiologically assessed dental factors specifically tooth morphology and position. This study investigated additional factors that have a bearing on the difficulty of extraction.Study design A prospective study undertaken by three clinical assistant grade surgeons who removed 354 single mandibular third molar teeth under day case anaesthesia over the 4-year period (1994–1998).Method Data relating to patient, dental and surgical variables were collected contemporaneously as the patients were treated. The difficulty of extraction was estimated by the surgeons pre-operatively using dental radiographic features and compared by the same surgeon within the actual surgical difficulty encountered at surgery. Operation time strongly related to both pre and post treatment assessments of difficulty and proved to be the best measure of surgical difficulty.Results Univariate analysis identified increased patient age, ethnic background, male gender, increased weight, bone impaction, horizontal angulation, depth of application, unfavourable root formation, proximity to inferior alveolar canal and surgeon as factors increasing operative time. Multivariate analysis showed that increasing age (P = 0.014), patient weight (P = 0.024), ethnicity (P = 0.019), application depth (P = 0.001), bone impaction (p=0.008) and unfavourable root formation (P = 0.009) were independent predictors for difficulty of extraction.Conclusions Half of the six independent factors that predicted surgical difficulty of third molar extraction were patient variables.

Occurrence of refeeding syndrome in adults started on artificial nutrition support: prospective cohort study

Background Refeeding syndrome is a potentially life-threatening condition characterised by severe intracellular electrolyte shifts, acute circulatory fluid overload and organ failure. The initial symptoms are non-specific but early clinical features are severely low-serum electrolyte concentrations of potassium, phosphate or magnesium. Risk factors for the syndrome include starvation, chronic alcoholism, anorexia nervosa and surgical interventions that require lengthy periods of fasting. The causes of the refeeding syndrome are excess or unbalanced enteral, parenteral or oral nutritional intake. Prevention of the syndrome includes identification of individuals at risk, controlled hypocaloric nutritional intake and supplementary electrolyte replacement. Objective To determine the occurrence of refeeding syndrome in adults commenced on artificial nutrition support. Design Prospective cohort study. Setting Large, single site university teaching hospital. Recruitment period 2007–2009. Participants 243 adults started on artificial nutrition support for the first time during that admission recruited from wards and intensive care. Main outcome measures Primary outcome: occurrence of the refeeding syndrome. Secondary outcome: analysis of the risk factors which predict the refeeding syndrome. Tertiary outcome: mortality due to refeeding syndrome and all-cause mortality. Results 133 participants had one or more of the following risk factors: body mass index <16–18.5≥(kg/m2), unintentional weight loss >15% in the preceding 3–6 months, very little or no nutritional intake >10 days, history of alcohol or drug abuse and low baseline levels of serum potassium, phosphate or magnesium prior to recruitment. Poor nutritional intake for more than 10 days, weight loss >15% prior to recruitment and low-serum magnesium level at baseline predicted the refeeding syndrome with a sensitivity of 66.7%: specificity was >80% apart from weight loss of >15% which was 59.1%. Baseline low-serum magnesium was an independent predictor of the refeeding syndrome (p=0.021). Three participants (2% 3/243) developed severe electrolyte shifts, acute circulatory fluid overload and disturbance to organ function following artificial nutrition support and were diagnosed with refeeding syndrome. There were no deaths attributable to the refeeding syndrome, but (5.3% 13/243) participants died during the feeding period and (28% 68/243) died during hospital admission. Death of these participants was due to cerebrovascular accident, traumatic injury, respiratory failure, organ failure or end-of-life causes. Conclusions Refeeding syndrome was a rare, survivable phenomenon that occurred during hypocaloric nutrition support in participants identified at risk. Independent predictors for refeeding syndrome were starvation and baseline low-serum magnesium concentration. Intravenous carbohydrate infusion prior to artificial nutrition support may have precipitated the onset of the syndrome.

Onychomycosis: the development of a clinical diagnostic aid for toenail disease. Part I. Establishing discriminating historical and clinical features

Background  The ideal method for diagnosing onychomycosis is unclear. Mycological investigation is currently the method of choice, although there is a false‐negative culture rate of at least 30%.