Age-related changes in consultations and antibiotic prescribing for acute respiratory infections, 1995–2000. Data from the UK General Practice Research Database

BACKGROUND

International studies using data aggregated for all ages have shown decreasing rates of general practice consultations for acute respiratory infections with fewer antibiotic prescriptions issued per consultation. The occurrence of different respiratory infections varies widely at different ages but we do not know whether prescribing has reduced equally in all age groups.

OBJECTIVE

We aimed to determine how reductions in consultation rates and antibiotic prescribing varied with age for different respiratory infections.

METHODS

Data were abstracted from the General Practice Research Database for 108 general practices in the UK (mean registered population 642 685). We estimated age-specific changes between 1995 and 2000 in consultation rates, and the proportion of consultations resulting in an antibiotic prescription for 'all respiratory infections' and for 'sore throat', 'ear infection', 'bronchitis' and 'chest infection'.

RESULTS

Consultation rates for 'all respiratory infections' declined in all age groups with the greatest decreases in children aged 1-4 years (41%), 5-10 year olds (53%) and 11-16 year olds (54%), whereas at 75-84 years the reduction was 28%. The pattern of greater reductions in children held for each separate condition even though the age of peak incidence varied. The relative reduction in antibiotic prescribing was greatest at 1-4 years (18%), 5-10 years (17%) and 11-16 years (17%), compared with 5% at 75-84 years. Antibiotic prescribing decreased most for sore throat and this was observed at all ages particularly in 5-10 year olds (relative reduction, 32%).

CONCLUSIONS

School age children account for the greatest reduction in consultations for acute respiratory infection. School age and preschool children account for the greatest reductions in antibiotic prescribing during the consultation. The rapid changes in consultation rates are unexplained.

Physical and psychological co-morbidity in irritable bowel syndrome: a matched cohort study using the General Practice Research Database

BACKGROUND

Irritable bowel syndrome is a common problem known to have a complex relationship with psychological disorders and other physical symptoms. Little information, however, is available concerning physical and psychological comorbidity in irritable bowel syndrome patients studied over an extended period.

AIM

To evaluate physical and psychological morbidity 2 years before and during 6 years after the time of diagnosis in incident cases of irritable bowel syndrome and control subjects.

METHODS

A matched cohort study was implemented in 123 general practices using the General Practice Research Database. Irritable bowel syndrome cases (n = 1827) and controls (n = 3654) were compared for 2 years before and 6 years after diagnosis.

RESULTS

The age-standardized incidence of irritable bowel syndrome in patients over 15 years of age was 1.9 per 1,000 in men and 5.8 per 1,000 in women. From 2 years before the date of diagnosis, more irritable bowel syndrome cases (13%) than controls (5%) consulted with depression or were prescribed antidepressant drugs. Consultation and prescription rates for anxiety were also higher before diagnosis, and both anxiety and depression remained prevalent up to 6 years after diagnosis. Asthma, symptoms of urinary tract infection, gall-bladder surgery, hysterectomy and diverticular disease were recorded more frequently in irritable bowel syndrome patients, who were also more likely than controls to be referred to hospital.

CONCLUSIONS

People who are diagnosed with irritable bowel syndrome experience more anxiety and depression and a range of physical problems, compared with controls; they are more likely to be referred to hospital.

Trends in antihypertensive and lipid-lowering therapy in subjects with type II diabetes: clinical effectiveness or clinical discretion?

Hypertension and lipid disorders in type II diabetes contribute to increased coronary risk, but optimal drug therapy has not been defined. We investigated primary care physicians choices of antihypertensive and lipid-lowering therapy for subjects with type II diabetes diagnosed with hypertension. Subjects were registered with 105 UK general practices in the General Practice Research Database and prescribed oral hypoglycaemic drugs for the first time between January 1993 and December 2001. We evaluated prescriptions for antihypertensive drugs in subjects with secondary diagnoses of hypertension in the first year following initiation of oral hypoglycaemic therapy. Data were analysed for 4519 diabetic subjects with diagnosed hypertension. Between 1993 and 2001, the proportion prescribed thiazide diuretics increased from 20 to 30%; angiotensin-converting enzyme (ACE) inhibitors from 35 to 45% and angiotensin receptor blockers from 0 to 8%. The proportion of subjects prescribed lipid-lowering therapy increased from 8% in 1993 to 33% in 2001, with the proportion prescribed statins increasing from 1 to 30%. At different general practices, the proportion prescribed thiazide diuretics ranged from 0 to 52%, beta-blockers from 5 to 60%, ACE inhibitors from 15 to 81%, and statins from 0 to 50%. Variation between practices was not explained by adjusting for age, sex, prevalent coronary heart disease or study year. Trends in drug utilisation were consistent with the evolving evidence base but there were wide variations in drug utilisation between practices. A more consistent approach to drug selection might be associated with improved patient outcomes.

IgG subclasses serum concentrations in a population of children with Down syndrome: comparative study with siblings and general population

Serum total IgG and subclasses were determined in three different groups of children: with Down syndrome, their siblings and general pediatric population. Several cases of IgG2 and IgG4 deficiency were identified, predominantly in children with Down syndrome. The differences, considering three age groups, were statistically significant for both groups in relation to the general population group, with an increase of IgG1 and IgG3 and a decrease in serum concentrations of IgG2 and IgG4. Down syndrome children and their siblings tend o have a similar variation of the IgG4 serum concentration levels (P < 0.05). The mechanisms of this concordance are not well understood. The results point out that an adequate strategy to improve the immune status of Down syndrome children could have a positive manifestation in the immune profile of their brothers.

Impact of infections on primary care--greater than expected

Though infection has declined as a cause of death it consumes a major proportion of primary care resources, and because of antibiotic resistance is increasingly important. We examined the burden of illness attributable to infection in primary care by analysing data from the fourth practice-based national morbidity survey which monitored all consultations by diagnosis in 470,000 persons over a 12 month period from September 1991 to August 1992. Rates of persons consulting, new episodes of illness and consultations were calculated according to the list of infections published by Wilson and Bhopal (W&B list), and as amended by the Communicable Disease Surveillance Centre (CDSC list); selected comparisons were made with national data on hospital derived finished consultant episodes and deaths. Forty-one percent of all registered persons consulted on at least one occasion during the year for infection (estimated by either list). Infections accounted for 40% of all new episodes of illness and 29% of all consultations; respiratory infections accounted for approximately half the infection total. New episode rates were highest in children aged less than 1 year and lowest in males 25-54 years and females 55-64 years. Except in infancy, rates were higher in females. There were 734 episodes of infection annually per 1,000 population reported in general practice compared with 20 per 1,000 finished consultant episodes. The average episode of infection prompted 1.2 general practice consultations. Improved management through more precise diagnosis by near patient tests is desirable, but is unlikely to be obtained cost effectively if consultation numbers or the time spent is substantially increased. These results emphasise the importance of adequate training for general practitioners in the natural history, epidemiology, diagnosis and treatment (pharmacology) of infection.

Thefurrygene ofDrosophilais important for maintaining the integrity of cellular extensions during morphogenesis

The Drosophila imaginal cells that produce epidermal hairs, the shafts of sensory bristles and the lateral extensions of the arista are attractive model systems for studying the morphogenesis of polarized cell extensions. We now report the identification and characterization of furry, an essential Drosophila gene that is involved in maintaining the integrity of these cellular extensions during morphogenesis. Mutations in furry result in the formation of branched arista laterals, branched bristles and a strong multiple hair cell phenotype that consists of clusters of epidermal hairs and branched hairs. By following the morphogenesis of arista laterals in pupae, we have determined that the branched laterals are due to the splitting of individual laterals during elongation. In genetic mosaics furry was found to act cell autonomously in the wing. The phenotypes of double mutant cells argue that furry functions independently of the frizzled planar polarity pathway and that it probably functions in the same pathway as the tricornered gene. We used a P-element insertion allele as a tag to clone the furry gene and found it to be a large and complicated gene that encodes a pair of large conserved proteins of unknown biochemical function.

Cell size and the morphogenesis of wing hairs in Drosophila

Almost all epidermal cells on the Drosophila wing produce a single cuticular hair. This is formed in the pupae from a microvillus-like cell projection called the prehair. Previous experiments have shown the existence of two mechanisms that ensure that only a single hair is made. One is the restriction of prehair initiation to a small subregion of the cell by the action of the frizzled tissue polarity pathway. The second is a system that ensures the integrity of the prehair. Mutations and drugs that inhibit the actin cytoskeleton lead to the splitting of a single prehair into multiple smaller hairs. We report that large polyploid cells produce multiple hairs both because they form multiple independent prehair initiation centers and because the larger than normal hairs these cells produce have a tendency to split. We show that reducing cell size by starvation partially suppresses the phenotype seen in polyploid cells and that increasing apical cell surface area by mechanical stretching also results in the formation of multiple prehair initiation centers. We also show that the frizzled tissue polarity pathway is functional in large polyploid cells even if it is unable to restrict prehair initiation to a small region of the cell. We conclude that both of these cellular systems are limited in their ability to scale to accommodate larger cell size.

The domineering non-autonomy of frizzled and van Gogh clones in the Drosophila wing is a consequence of a disruption in local signaling

The frizzled (fz) gene is required for the development of distally pointing hairs on the Drosophila wing. It has been suggested that fz is needed for the propagation of a signal along the proximal distal axis of the wing. The directional domineering non-autonomy of fz clones could be a consequence of a failure in the propagation of this signal. We have tested this hypothesis in two ways. In one set of experiments we used the domineering non-autonomy of fz and Vang Gogh (Vang) clones to assess the direction of planar polarity signaling in the wing. prickle (pk) mutations alter wing hair polarity in a cell autonomous way, so pk cannot be altering a global polarity signal. However, we found that pk mutations altered the direction of the domineering non-autonomy of fz and Vang clones, arguing that this domineering non-autonomy is not due to an alteration in a global signal. In a second series of experiments we ablated cells in the pupal wing. We found that a lack of cells that could be propagating a long-range signal did not alter hair polarity. We suggest that fz and Vang clones result in altered levels of a locally acting signal and the domineering non-autonomy results from wild-type cells responding to this abnormal signal.

Families, groups and clusters of local and health authorities: revised for authorities in 1999

This is the second of two articles describing the revision of The ONS classification of local and health authorities of Great Britain to take account of area changes in the 1990's. It presents local authorities in Great Britain as at April 1999 in terms of Families, Groups and Clusters, based on 37 socio-economic and demographic variables from the 1991 Census. Health authorities are presented in terms of Families and Groups only, based on the same variables. The previous article (in Population Trends 98) presented, for each local and health authority, up to four other authorities to which it is 'most similar'.

Which authorities are alike?

This article describes the first results from the recent revision to The ONS classification of local and health authorities of Great Britain to allow for boundary changes. For each local and health authority of Great Britain as at April 1999 it presents 'most similar' authorities as measured by a selection of 37 socioeconomic and demographic variables from the 1991 Census. These results will assist local and health authorities in identifying other appropriate authorities for comparative studies. A second article, to be published in Population Trends 99, will present the results of the analysis to identify groups of authorities in a hierarchy of new Clusters, Groups and Families for the revised classification.

The Drosophila tissue polarity gene starry night encodes a member of the protocadherin family

The tissue polarity genes control the polarity of hairs, bristles and ommatidia in the adult epidermis of Drosophila. We report here the identification of a new tissue polarity gene named starry night (stan). Mutations in this essential gene alter the polarity of cuticular structures in all regions of the adult body. The detailed polarity phenotype of stan on the wing suggested that it is most likely a component of the frizzled (fz) pathway. Consistent with this hypothesis, stan appears to be downstream of and required for fz function. We molecularly cloned stan and found that it encodes a huge protocadherin containing nine cadherin motifs, four EGF-like motifs, two laminin G motifs, and seven transmembrane domains. This suggests that Stan functions in signal reception, perhaps together with Fz.

Densely methylated sequences that are preferentially localized at telomere-proximal regions of human chromosomes

We have constructed a library of densely methylated DNA sequences from human blood DNA by selecting fragments with a high affinity for a methyl-CpG binding domain (MBD) column. PCR analysis of the library confirmed the presence of known densely methylated CpG island sequences. Analysis of random clones, however, showed that the library was dominated by sequences whose G+C content and CpG frequency were intermediate between those of bulk genomic DNA and bona fide CpG islands. When human chromosomes were probed with the library by fluorescent in situ hybridisation (FISH), the predominant sites of labelling were at terminal regions of many chromosomes, approximately corresponding to T-bands. Analysis of the methylation status of random clones indicated that all were heavily methylated at CpGs in blood DNA, but many were under-methylated in sperm DNA. Lack of methylation in germ cells may reduce CpG depletion at some sub-terminal sequences and result in a high density of methyl-CpG when these regions become methylated in somatic cells.

Parallel pathways, noise masking and glaucoma detection: behavioral and electrophysiological measures

PURPOSE

We tested the hypothesis that because of their reduced neural efficiency, glaucoma patients should have increasingly impaired thresholds as external noise is added to a stimulus.

METHOD

We compared the performance of 20 normals (mean age = 39 years) with that of 15 patients with early glaucoma or at very high risk for glaucoma (mean age 45 years). All patients had normal visual acuity. Contrast thresholds were measured on two sets of tasks: (1) behavioral and (2) sweep visually evoked potentials (VEPs). Two stimuli were used (a) 7.5 Hz reversing gratings of 0.69 cpd, and (b) 5.5 cpd gratings. Noise was binary and contrast varied from 0 to 80%. Psychophysical thresholds were determined using a staircase which employed a spatial four alternative forced choice procedure (4AFC) and converged on 50% correct. Sweep VEP thresholds were determined by extrapolation to zero volts as a function of log contrast.

RESULTS

Differences between normal subjects and patients with early glaucoma were not significant without noise. Both the absolute size of the difference and its significance increased as noise level increased. For the behavioral thresholds these trends were clearer with the 5.5 cpd grating, while for the sweep VEPs they were more clear for the 0.69 cpd grating.

CONCLUSION

The performance deficit of glaucoma patients which may be minimal under normal testing conditions is magnified when external noise is added to the stimulus. VEPs and psychophysical thresholds show interesting differences in their sensitivity to this effect. Implications for the early detection of glaucoma are discussed.

Estimation of SELEX pool size by measurement of DNA renaturation rates

We report a general method of measuring the complexity of SELEX pools. In analogy to measurements of genome size by C0t analysis, the complexity of a SELEX pool is measured by determining the reannealing rate of its double-stranded PCR product. We applied this technique to study the selection dynamics of a recently reported SELEX to neutrophil elastase. We found that the number of sequences decreased from 10(7) in round 6 to approximately 60 by round 15, the final round. The intermediate rounds are a mixture of a high abundance/low complexity pool with a low abundance/high complexity pool. As the SELEX progresses, the former pool expands at the expense of the latter. This technique should be useful for studying and optimizing SELEX dynamics, as well as for monitoring the progress of SELEX experiments.

Nonmethylated transposable elements and methylated genes in a chordate genome

The genome of the invertebrate chordate Ciona intestinalis was found to be a stable mosaic of methylated and nonmethylated domains. Multiple copies of an apparently active long terminal repeat retrotransposon and a long interspersed element are nonmethylated and a large fraction of abundant short interspersed elements are also methylation free. Genes, by contrast, are predominantly methylated. These data are incompatible with the genome defense model, which proposes that DNA methylation in animals is primarily targeted to endogenous transposable elements. Cytosine methylation in this urochordate may be preferentially directed to genes.

Patients consulting with Crohn's disease in primary care in England and Wales

OBJECTIVE

To determine annual incidence and prevalence for patients consulting their GP because of Crohn's disease in England and Wales and compare demographic details with matched controls.

DESIGN

We used the fourth Morbidity Statistics in General Practice study (MSGP-4) which covered 468 042 person-years during a 12-month period in 1991-92.

METHODS

All GPs reporting a patient with Crohn's disease in MSGP-4 were sent a questionnaire to confirm the diagnosis and obtain supportive details (surgical, pathological, radiological and/or endoscopic). Data concerning ethnicity, social class, smoking status, living in an urban or rural environment and employment had been collected previously. Conditional logistic regression models were used to analyse the data for cases and matched controls.

RESULTS

Three hundred and fifteen patients were reported to have Crohn's disease. Replies were obtained to 251 (80%) questionnaires. The diagnosis of Crohn's disease was confirmed in 184 cases (89%) and refuted in 23 cases (11%) -- details were unavailable for 44 patients. The mean age of patients was 44 years, the female:male ratio was 1.46:1, and 108 (59%) patients had required surgery. Thirty-three of 178 (18.5%) patients were diagnosed within the study period. Hence, this study detected a prevalence for consulting Crohn's disease of 54.6-59.8/100,000 and an annual incidence of 10.1-11.1/100,000 in 1991-92. No significant differences were found between cases (n = 291) and controls (n = 1682) with regard to ethnicity, social class, smoking or living in an urban/rural environment. Patients with Crohn's disease had similar employment levels as controls, but were significantly more likely to be registered as permanently sick, odds ratio 4.01 (CI 2.21-7.29).

CONCLUSIONS

This national survey, including 1% of the population, suggests there are approximately 30,600 patients consulting their GP because of Crohn's disease in England and Wales, with 5700 new cases diagnosed per year.

Potential for suicide prevention in primary care? An analysis of factors associated with suicide

BACKGROUND

General practitioners (GPs) need to be aware of the risk factors for suicide. GP records may provide clues to identifying the relative importance of such risk factors.

AIMS

To identify, in suicide cases and matched controls, the patterns of consultation, diagnosis, and treatment of mental illness, and recording of risk factors for suicide. To examine the usefulness of data routinely collected by GPs in computerized databases to investigate treatment of patients in general practice prior to suicide.

METHOD

Case control study using GP records from the General Practice Research Database (GPRD). Three controls selected for each case, matched for age, sex, and duration of registration with practice. Information extracted of the prevalence of major disease; diagnosis of, and treatment, or referral for, mental illness; frequency of recording of recent life events; and consultations with the GP in the 12 months prior to death.

RESULT

Of the 339 suicide cases recorded, 80% were male, which is similar to the national percentage for this age group. Females were more likely than males to have a history of mental illness and to have been diagnosed and treated for mental illness in the 12 months before death (59% versus 35%), and women were more likely to have previously attempted suicide (47% versus 27%). There was no significant difference between males and females in period of time since last contact with GP practice, but females consulted more frequently. Twenty-nine per cent of cases had not consulted their GP in the six months prior to death. In multivariate analysis, the following were identified as independent risk factors: history of attempted suicide; untreated serious mental illness (odds ratio > 20); recent (past 12 months) marital life event; alcohol abuse; frequent consultations with GP; and previous mental illness. Recording of life events by GPs was poor.

CONCLUSIONS

Females at risk of suicide are more likely than males to have been diagnosed and treated for mental illness. It is likely that GPs are under-diagnosed and under-treating males at risk. Data from the GPRD give comparable results to those from other studies. The GPRD is a potentially useful tool for research into relatively uncommon events in general practice.

Van Gogh: a new Drosophila tissue polarity gene

Mutations in the Van Gogh gene result in the altered polarity of adult Drosophila cuticular structures. On the wing, Van Gogh mutations cause an altered polarity pattern that is typical of mutations that inactivate the frizzled signaling/signal transduction pathway. The phenotype however, differs from those seen previously, as the number of wing cells forming more than one hair is intermediate between that seen previously for typical frizzled-like or inturned-like mutations. Consistent with Van Gogh being involved in the function of the frizzled signaling/signal transduction pathway, Van Gogh mutations show strong interactions with mutations in frizzled and prickle. Mitotic clones of Van Gogh display domineering cell nonautonomy. In contrast to frizzled clones, Van Gogh clones alter the polarity of cells proximal (and in part anterior and posterior) but not distal to the clone. In further contrast to frizzled clones, Van Gogh clones cause neighboring wild-type hairs to point away from rather than toward the clone. This anti-frizzled type of domineering nonautonomy and the strong genetic interactions seen between frizzled and Van Gogh suggested the possibility that Van Gogh was required for the noncell autonomous function of frizzled. As a test of this possibility we induced frizzled clones in a Van Gogh mutant background and Van Gogh clones in a frizzled mutant background. In both cases the domineering nonautonomy was suppressed consistent with Van Gogh being essential for frizzled signaling.

Use of the census samples of anonymised records (SARs) and survey data in combination to obtain estimates at local authority level

"The Samples of Anonymised Records (SARs) provide large representative samples of 278 small areas of Britain and are thus of great value to planners. This paper describes an approach which takes advantage of the fact that the SARs comprise individual records. Estimates of the proportions of local authority populations suffering serious illness were produced by use of data from the 4th National General Practitioner Morbidity survey and the 2% anonymised sample of individual 1991 Census records. These estimates were compared with external validation criterion, all-cause mortality. The correlation was high, providing some evidence of the validity of the approach."

Oesophageal, rectal, axillary, tympanic and pulmonary artery temperatures during cardiac surgery

PURPOSE

The gradient between temperatures measured at different body sites is not constant; one factor which will change this gradient is rapid changes in body temperature. Measurement of this gradient was done in patients undergoing rapid changes in body temperature to establish the best site to measure temperature and to compare two brands of commercial tympanic thermometers.

METHOD

A total of 228 sets of temperatures were measured from probes in the oesophagus, rectum, and axilla and from two brands of tympanic thermometer and compared with pulmonary artery (PA) temperature in 18 adults during cardiac surgery.

RESULTS

Measurements from the oesophageal site was closest to PA readings (mean difference 0.0 +/- 0.5 degree C) compared with IVAC tympanic thermometer (mean difference -0.3 +/- 0.5 degree C), Genius tympanic thermometer (mean difference -0.4 +/- 0.5 degree C), axillary (mean difference 0.2 +/- 1.0 degrees C) and rectal (mean difference -0.4 +/- 1.0 degree C) readings. When data during cooling were analysed separately, all sites had similar gradients from PA except for rectal, which was larger. On rewarming, oesophageal readings were closest to PA readings; tympanic readings were closer to PA than were rectal or axillary readings. Readings from the two brands of tympanic thermometer were equivalent.

CONCLUSION

Oesophageal temperature is more accurate and will reflect rapid changes in body temperature better than tympanic, axillary, or rectal temperature. When oesophageal temperature cannot be measured, tympanic temperature done by a trained operator should become the reading of choice.

Mutations in the cadherin superfamily member gene dachsous cause a tissue polarity phenotype by altering frizzled signaling

The adult cuticular wing of Drosophila is covered by an array of distally pointing hairs that reveals the planar polarity of the wing. We report here that mutations in dachsous disrupt this regular pattern, and do so by affecting frizzled signaling. dachsous encodes a large membrane protein that contains many cadherin domains and dachsous mutations cause deformed body parts. We found that mutations in dachsous also result in a tissue polarity phenotype that at the cellular level is similar to frizzled, dishevelled and prickle, as many cells form a single hair of abnormal polarity. Although their cellular phenotype is similar to frizzled, dishevelled and prickle, dachsous mutant wings display a unique and distinctive abnormal hair polarity pattern including regions of reversed polarity. The development of this pattern requires the function of frizzled pathway genes suggesting that in a dachsous mutant the frizzled pathway is functioning - but in an abnormal way. Genetic experiments indicated that dachsous was not required for the intracellular transduction of the frizzled signal. However, we found that dachsous clones disrupted the polarity of neighboring wild-type cells suggesting the possibility that dachsous affected the intercellular signaling function of frizzled. Consistent with this hypothesis we found that frizzled clones in a dachsous mutant background displayed enhanced domineering non-autonomy, and that the anatomical direction of this domineering non-autonomy was altered in regions of dachsous wings that have abnormal hair polarity. The direction of this domineering nonautonomy was coincident with the direction of the abnormal hair polarity. We conclude that dachsous causes a tissue polarity phenotype because it alters the direction of frizzled signaling.