Proper orthogonal and dynamic mode decomposition of sunspot data

High-resolution solar observations show the complex structure of the magnetohydrodynamic (MHD) wave motion. We apply the techniques of proper orthogonal decomposition (POD) and dynamic mode decomposition (DMD) to identify the dominant MHD wave modes in a sunspot using the intensity time series. The POD technique was used to find modes that are spatially orthogonal, whereas the DMD technique identifies temporal orthogonality. Here, we show that the combined POD and DMD approaches can successfully identify both sausage and kink modes in a sunspot umbra with an approximately circular cross-sectional shape. This article is part of the Theo Murphy meeting issue 'High-resolution wave dynamics in the lower solar atmosphere'.

SAT0229 PROTEOMIC ANALYSIS REVEALS ASSOCIATION BETWEEN IMMUNE-METABOLIC BIOMARKERS AND CLINICAL SYMPTOMS IN SICCA PATIENTS

Background:

Sjögren’s syndrome (SS) is a systemic autoimmune disease whose main characteristic is involvement of the exocrine glandular system. Thus, its most common clinical manifestation is eye and mouth dryness which, alongside fatigue and pain, contributes to poor health-related quality of life (HRQoL). A growing body of evidence recognises the adipose tissue as an active endocrine organ secreting bioactive mediators involved in metabolic and inflammatory disorders. A relationship between obesity and symptoms in SS has not yet been elucidated.

Objectives:

To explore potential associations between obesity-related immune-metabolic biomarkers and clinical symptoms in SS and sicca patients.

Methods:

Proteomics analysis of 184 cardio-immuno-metabolic proteins was assessed on sera from 53 SS (50 females (F), 3 males (M); mean age 54 years) and 60 sicca (56 F, 4 M; mean age 57 years) patients. Participants were enrolled in the Birmingham Optimising Assessment in Sjögren`s Syndrome (OASIS) cohort and examinations included the EULAR SS Patient Reported Index (ESSPRI), Schirmer’s test, unstimulated whole saliva, minor labial salivary gland biopsy, EuroQoL-5 dimension (EQ-5D) tool, immunological parameters, body max index (BMI) and Hb1Ac. Participants with SS fulfilled 2016 ACR/EULAR criteria. Non-SS sicca patients were anti-Ro antibody negative, displayed objective oral and/or ocular dryness, and did not have a physician diagnosis for SS. Linear regression analysis and univariate models were performed to identify the key predictors of symptoms.

Results:

HRQoL as measured as EQ-5D utility values, symptoms as assessed by ESSPRI, and BMI did not differ between the SS and sicca group. However, strong correlations between BMI (or fat or fat-free mass) and EQ-5D and ESSPRI scores were found in the sicca but not in the SS group. Among several proteins investigated, ADM, TNFRSF13B, FGF23, IL10RB, CD5, CD40, IL1RA, TNRSFN9, TNFRSF10A, TNFRSF11A, TRAILR2, GAL9, SPON2, ACE2, LEP, CD4, IL12B, SLAMF1, PD-L1 positively correlated with symptoms in the sicca group (R ≥ 0.3; Holm’s adjusted P ≤ 0.05). Adrenomedullin (ADM) showed the strongest correlation with ESSPRI (R = 0.56; P < 0.0001); age (R = 0.45; P = 0.0003); BMI (R = 0.43, P = 0.0008); Ocular Surface Disease Index (R = 0.32, P = 0.03); EQ-5D utility value (R = -0.45, P = 0.001) and VAS patient (R = -0.41, P = 0.008). There was no association between ADM and gender, Schirmer`s test, disease and symptom duration (P > 0.05). ADM was independently associated with ESSPRI scores in non-SS sicca patients when corrected for BMI, age, HbA1c, depression and anxiety scores. None of the above mentioned proteins correlated with clinical symptoms in the SS group.

Conclusion:

The study suggests that obesity-related immune-metabolic factors may play a role in regulating the symptoms in non-SS sicca patients. ADM appears to be a strong independent predictor of symptoms in these patients but not in SS.

Disclosure of Interests:

Valentina Pucino: None declared, Jason D. Turner: None declared, Florian Kollert Employee of: Novartis, Saaeha Rauz: None declared, Andrea Richard: None declared, Jon Higham: None declared, Ana Poveda-Gallego: None declared, Simon J. Bowman Consultant of: Astrazeneca, Biogen, BMS, Celgene, Medimmune, MTPharma, Novartis, Ono, UCB, xtlbio, Glapagos, Speakers bureau: Novartis, Francesca Barone: None declared, Benjamin Fisher: None declared

SAT0215 HISTORY OF TONSILLECTOMY IS ASSOCIATED WITH GLANDULAR INFLAMMATION IN SJÖGREN’S SYNDROME

Background:

The palatine tonsils are secondary lymphoid-organs that serve as the first line of defense against pathogens. Whether history of tonsillectomy (TE) is associated with the phenotype of Sjögren`s syndrome (SjS) has not been investigated to date.

Objectives:

To test whether TE is linked to SjS phenotype and disease activity scores.

Methods:

A total of 183 patients from the Optimising Assessment in Sjögren`s Syndrome (OASIS) cohort with SjS or non-SjS sicca syndrome were analysed. Patients with SjS fulfilled 2016 ACR/EULAR classification for primary SjS; sicca patients had objective and/or subjective dryness, but were anti-Ro/SSA negative and had no physician diagnosis of SjS. One SjS patient who had TE around the time of symptom onset was excluded.

Results:

Of the total cohort, 116 were diagnosed with SjS (86.2% SSA/Ro positive) and 67 with non-SjS sicca syndrome. Overall, 29% (53/183) had TE; 24.1% of the SjS patients (28/116) and 37.3% of the sicca patients (25/67). The prevalence of TE was higher in sicca than in SjS (p=0.043). The median age at TE was 8 (range 3-50) years and did not differ between SjS and sicca patients (p=0.629). Neither age at first symptoms (p=0.093) nor disease duration (p=0.623) were associated with TE in patients with SjS. SjS patients with TE showed a higher average histological focus score (2.1 (1.2-2.8) vs. 1.3 (0.0-4.3); p=0.049), and were more likely to have activity in the glandular (53.6 vs. 20.5%; p=0.001) and constitutional (39.3 vs. 14.9%, p=0.014) domains of the ESSDAI, and lower levels of IgG (12.2 (7.8-35.6) vs. 15.6 (5.7-56.4) g/l; p=0.012) and IgA (2.3 (0.9-6.6) vs. 2.9 (0.7-9.4) g/l; p=0.032). Whereas there was no difference in EQ5D utility values (p=0.718), VAS global health was significantly lower in the patients with SjS who had TE (58 (10-78) vs. 70 (10-97); p=0.021). There was no association between the status of TE and autoantibodies (SSA, SSB, RF), lachrymal and salivary glands function (Schirmer`s test, unstimulated saliva flow), complement (C3, C4), serum levels of free light chains, β2-microglobulin, ESSPRI, or total ESSDAI (all p-values >0.1). Of 181 patients, 12.7% (23/283) had appendectomy (AE); 10.5% (12/114) of the SjS patients and 16.4 %(11/67) of the sicca patients (p=0.258). With the exception of lower unstimulated salivary flow (0.086 (0.01-0.43) vs. 0.11 (0.0-1.3) ml/min; p=0.026) in SjS patients with AE, there were no differences in disease phenotype between SjS patients with and without AE (all p-values >0.1).

Conclusion:

History of TE in SjS is associated with higher average focus scores and with glandular swelling. It could be speculated that the absence of palatine tonsils is compensated by enhanced lymphocytic infiltrates in the salivary glands. Further research is required to determine if TE is a risk factor for both SjS and non-SjS sicca and to determine the role of the tonsils in the generation of hypergammaglobulinaemia in SjS.

Disclosure of Interests:

Florian Kollert Employee of: Novartis, Valentina Pucino: None declared, Saaeha Rauz: None declared, Andrea Richard: None declared, Jon Higham: None declared, Ana Povedo-Gallego: None declared, Rachel M. Brown: None declared, Timothy Bates: None declared, Simon J. Bowman Consultant of: Astrazeneca, Biogen, BMS, Celgene, Medimmune, MTPharma, Novartis, Ono, UCB, xtlbio, Glapagos, Speakers bureau: Novartis, Francesca Barone: None declared, Benjamin Fisher: None declared

Validation of an Oral Disease Severity Score (ODSS) tool for use in oral mucous membrane pemphigoid

BACKGROUND

Mucous membrane pemphigoid (MMP) is a rare autoimmune bullous disease predominantly affecting the oral mucosa. Optimal management relies upon thorough clinical assessment and documentation at each visit.

OBJECTIVES

The primary aim of this study was to validate the Oral Disease Severity Score (ODSS) for the assessment of oral involvement in MMP. We also compared its inter- and intraobserver reliability with those of the oral parts of the Mucous Membrane Pemphigoid Disease Area Index (MMPDAI), Autoimmune Bullous Skin Disorder Intensity Score (ABSIS) and Physician's Global Assessment (PGA).

METHODS

Fifteen patients with mild-to-moderately severe oral MMP were scored for disease severity by 10 oral medicine clinicians from four U.K. centres using the ODSS, the oral sections of MMPDAI and ABSIS, and PGA. Two clinicians rescored all patients after 2 h.

RESULTS

In terms of reliability, the interobserver ODSS total score intraclass correlation coefficient (ICC) was 0·97, MMPDAI activity 0·59 and damage 0·15, ABSIS total 0·84, and PGA 0·72. The intraobserver ICCs (two observers) for ODSS total were 0·97 and 0·93; for MMPDAI activity 0·93 and 0·70 and damage 0·93 and 0·79; for ABSIS total 0·99 and 0·94; and for PGA 0·92 and 0·94. Convergent validity between ODSS and MMPDAI was good (correlation coefficient 0·88). The mean ± SD time for completion of ODSS was 93 ± 31 s, with MMPDAI 102 ± 24 s and ABSIS involvement 71 ± 18 s. The PGA took < 5 s.

CONCLUSIONS

This study has validated the ODSS for the assessment of oral MMP. It has shown superior interobserver agreement over MMPDAI, ABSIS and PGA, and superior intraobserver reliability to MMPDAI. It is quick and easy to perform. What's already known about this topic? There are no validated scoring methodologies for oral mucous membrane pemphigoid (MMP). Proposed disease activity scoring tools for MMP include the Mucous Membrane Disease Area Index (MMPDAI) and the Autoimmune Bullous Skin Disorder Intensity Score (ABSIS). The Oral Disease Severity Score (ODSS) has been validated for use in oral pemphigus vulgaris (PV). It has been shown to be reliable and sensitive in both lichen planus (LP) and MMP. What does this study add? The ODSS has been shown to be a thorough, sensitive and reproducible, yet quick scoring tool for the assessment of oral involvement in MMP. Its versatility for use in oral PV, MMP and LP is an added advantage over other scoring methodologies. What are the clinical implications of this work? We propose that the ODSS be used as a clinical scoring tool for monitoring activity in oral MMP in clinical practice as well as for use in multicentre studies.

PeerWise provides significant academic benefits to biological science students across diverse learning tasks, but with minimal instructor intervention

We demonstrate that student engagement with PeerWise, an online tool that allows students to author and answer multiple-choice questions (MCQs), is associated with enhanced academic performance across diverse assessment types on a second year Genetics course. Benefits were consistent over three course deliveries, with differential benefits bestowed on groups of different prior ability. A rating scheme, to assess the educational quality of students' questions, is presented and demonstrates that our students are able intuitively to make such quality assessments, and that the process of authoring high quality questions alone does not explain the academic benefits. We further test the benefits of providing additional PeerWise support and conclude that PeerWise works efficiently with minimal intervention, and can be reliably assessed using automatically generated PeerWise scores.

Gingipain-dependent degradation of mammalian target of rapamycin pathway proteins by the periodontal pathogen Porphyromonas gingivalis during invasion

Porphyromonas gingivalis and Tannerella forsythia are gram-negative pathogens strongly associated with periodontitis. Their abilities to interact, invade and persist within host cells are considered crucial to their pathogenicity, but the mechanisms by which they subvert host defences are not well understood. In this study, we set out to investigate whether P. gingivalis and T. forsythia directly target key signalling molecules that may modulate the host cell phenotype to favour invasion and persistence. Our data identify, for the first time, that P. gingivalis, but not T. forsythia, reduces levels of intracellular mammalian target of rapamycin (mTOR) in oral epithelial cells following invasion over a 4-h time course, via the action of gingipains. The ability of cytochalasin D to abrogate P. gingivalis-mediated mTOR degradation suggests that this effect is dependent upon cellular invasion. We also show that levels of several other proteins in the mTOR signalling pathway are modulated by gingipains, either directly or as a consequence of mTOR degradation including p-4E-BP1. Taken together, our data suggest that P. gingivalis manipulates the mTOR pathway, providing evidence for a potentially novel mechanism by which P. gingivalis mediates its effects on host cell responses to infection.

Progestogens versus oestrogens and progestogens for irregular uterine bleeding associated with anovulation

BACKGROUND

Dysfunctional uterine bleeding (DUB) is excessively heavy, prolonged or frequent bleeding of uterine origin which is not due to pregnancy or to recognisable pelvic or systemic disease. Anovulation may be inferred from a number of observations but, in the normal clinical situation, anovulation is often assumed when a woman presents with heavy, prolonged or frequent bleeding, particularly in those who are at the extremes of reproductive life and in women known to have polycystic ovarian syndrome. Menstrual bleeding that is irregular or excessive is poorly tolerated by the majority of women. Changes in the length of the menstrual cycle generally imply disturbances of the hypothalamo-pituitary-ovarian (HPO) axis. In anovulatory DUB with acyclic (irregular) oestrogen production there will be no progesterone withdrawal from oestrogen primed endometrium and so cycles are irregular. Prolonged oestrogen stimulation may cause a build up of endometrium with erratic bleeding as it breaks down and is expelled. This is the rationale for using cyclical progestogens during the second half of the menstrual cycle, in order to provoke a regular withdrawal bleed. Continuous progestogen is intended to induce endometrial atrophy and hence to prevent oestrogen-stimulated endometrial proliferation. Progestogens, and oestrogens and progestogens in combination are already widely used in the management of irregular or excessive bleeding due to DUB but the regime, dose and type of progestogen used varies widely, with little consensus about the optimum treatment approach.

OBJECTIVES

To determine the effectiveness and acceptability of progestogens alone and oestrogens and progestogens in combination in the management of irregular bleeding associated with anovulation.

SEARCH STRATEGY

We searched the Cochrane Menstrual Disorders and Subfertility Group Trials Register (searched 4 May 2007), Cochrane Central Register of Controlled Trials (CENTRAL) (The Cochrane Library 2007, Issue 2), MEDLINE (1966 to May 2007), EMBASE (1985 to May 2007), CINAHL (1982 to May 2007), Biological Abstracts (1969 to May 2007), Current Contents (1980 to 2007) and reference lists of articles.

SELECTION CRITERIA

All randomised controlled trials of progestogens (via any route) alone or in combination with oestrogens in the treatment of irregular bleeding associated with anovulation.

DATA COLLECTION AND ANALYSIS

Study quality assessment and data extraction were carried out independently by two review authors. Both authors were experts in the content matter.

MAIN RESULTS

No randomised trials were identified which compared progestogens with oestrogens and progestogens or with placebo in the management of irregular bleeding associated with anovulation. Only one small, non-randomised study compared two progestogen regimes in the management of heavy and irregular bleeding in women with confirmed anovulation. One randomised study compared the effects of two progestogens on endometrial histology in women with a variety of menstrual symptoms, half of whom had cystic glandular hyperplasia.

AUTHORS' CONCLUSIONS

There is a paucity of randomised studies relating to the use of progestogens and of oestrogens and progestogens in combination in the treatment of irregular bleeding associated with anovulation. Further research is needed to establish the role of these treatments in the management of this common gynaecological problem.

Commentary: How can we make our medical students enthusiastic about a future in obstetrics and gynaecology?

Falling recruitment to obstetrics and gynaecology (O&G) among UK-trained undergraduates is a pressing concern. The reasons for this are multifactorial and include the previous restriction on the number of postgraduate training places. Undergraduate placements are a key time to encourage potential recruits into the specialty. A recent survey demonstrated various changes within medical school attachments over the past 15 years that are having a mixed influence on the undergraduate O&G experience. These are explored in relation to their potential impact on recruitment.

Peptic ulceration in general practice in England and Wales 1994-98: period prevalence and drug management

BACKGROUND

Little is known about the burden of peptic ulcer in the community.

AIMS

To examine recent time trends in the period prevalence of peptic ulceration and its drug management, in England and Wales.

METHODS

For each year between 1994 and 1998, information on patients with a diagnosis of peptic ulceration was extracted from the General Practice Research Database.

RESULTS

The annual age-standardized period prevalence of peptic ulceration decreased from 3.3/1000 in 1994 to 1.5/1000 in 1998 for men, and from 1.8/1000 to 0.9/1000 for women. This decline was more evident among younger people, and among males registered with practices located in the most deprived electoral wards compared to those located in the least deprived. The proportion of patients receiving H2 receptor antagonists declined from 68% in 1994 to 41% in 1998. In contrast, the proportion prescribed proton pump inhibitors rose from 46% to 66%.

CONCLUSIONS

Over a 5-year period, the period prevalence of peptic ulceration has decreased markedly, especially among younger people and those from more deprived areas.

Recent trends in admissions and mortality due to peptic ulcer in England: increasing frequency of haemorrhage among older subjects

BACKGROUND

Although overall admission rates for peptic ulcer in England declined from the 1950s up until the mid 1980s, perforations among older women increased, possibly due to increasing use of non-steroidal anti-inflammatory drugs (NSAID). Since then, proton pump inhibitors, antibiotic treatment for Helicobacter pylori, low dose aspirin, and selective serotonin reuptake inhibitors (SSRI) have been introduced Aims: To determine time trends for hospital admissions for peptic ulcer from 1989 to 1999 (England), mortality from 1958 to 1998 (England and Wales), and prescriptions for ulcer healing drugs, aspirin, NSAID, oral anticoagulants, and SSRI from 1990 to 1999 (England).

METHODS

Hospital episode statistics for admissions and mortality were obtained from the Office of National Statistics: community prescription data from Statistics Division 1E of the Department of Health.

RESULTS

Between 1989/90 and 1998/99, there was a marked rise in admissions for haemorrhage in older patients, particularly from duodenal ulcer. Perforations from gastric ulcer declined but perforations from duodenal ulcer increased among men at older ages. Since the mid 1980s mortality has declined in all age groups except for older women with duodenal ulcer. The number of prescriptions for histamine H(2) receptor antagonists remained constant but those for proton pump inhibitors increased by 5000%, aspirin 75mg by 460%, oral anticoagulants by 200%, and NSAID by 13% between 1990 and 1999. Since the introduction of SSRI in 1991, prescriptions have increased 15-fold.

CONCLUSIONS

Admission rates for gastric and duodenal ulcer haemorrhage and duodenal ulcer, but not gastric ulcer perforation, increased among older subjects, over a time when prescriptions for proton pump inhibitors, low dose aspirin, oral anticoagulants, and SSRI increased.

Endometrial bleeding in hormone replacement therapy users: preliminary findings regarding the role of matrix metalloproteinase 9 (MMP-9) and tissue inhibitors of MMPs

OBJECTIVE

To establish the effect of hormone replacement therapy (HRT) on the expression of matrix metalloproteinase 9 (MMP-9) and the tissue inhibitor of MMPs, TIMP-1, in the endometrium of postmenopausal and perimenopausal women.

DESIGN

Prospective observational study.

SETTING

United Kingdom teaching hospital.

PATIENT(S)

Thirty-one perimenopausal and postmenopausal HRT recipients, with a control group of eight postmenopausal women not undergoing HRT.

INTERVENTION(S)

Prospective record of bleeding patterns and endometrial biopsy.

MAIN OUTCOME MEASURE(S)

Endometrial histology, bleeding patterns, MMP-9, and TIMP-1 expression.

RESULT(S)

MMP-9 and TIMP-1 are expressed in benign postmenopausal endometrium. Expression of both molecules is reduced in HRT recipients compared with non-HRT recipients.

CONCLUSION(S)

Exposure to HRT appears to alter endometrial expression of MMP-9 and TIMP-1 and also the local balance between these molecules. This alteration may promote breakdown of the endometrial extracellular matrix and blood vessels and hence bleeding.

Folic acid supplements are more effective than increased dietary folate intake in elevating serum folate levels

In 1992, recommendations were disseminated aimed at reducing the incidence of neural tube defects. Women were advised to increase consumption of folic acid supplements and dietary folates during the periconceptional period and a major integrated national campaign was launched to help achieve this. In this study we found that only one-quarter of the women with an uncomplicated obstetric history and 51% with a complicated obstetric history took supplements for the recommended time period. Dietary modification was extremely unusual. Serum analysis demonstrated that intake of folic acid supplements provides a greater elevation in serum folate levels than dietary food intake, suggesting dietary manipulation is an ineffective strategy and that efforts would be better focused on increasing supplement intake at a clinically important time. More effective education strategies are required, and since approximately one-third of pregnancies are unplanned, fortification of foods with folic acid is warranted.

Progestogens versus oestrogens and progestogens for irregular uterine bleeding associated with anovulation

BACKGROUND

Dysfunctional uterine bleeding (DUB) is "excessively heavy, prolonged or frequent bleeding of uterine origin which is not due to pregnancy or to recognizable pelvic or systemic disease". Anovulation may be inferred from a number of observations but in the normal clinical situation, anovulation is often assumed when a woman presents with heavy, prolonged or frequent bleeding, particularly in those at the extremes of reproductive life and in women known to have the polycystic ovarian syndrome. Menstrual bleeding that is irregular or excessive is usually poorly tolerated by the majority of women. Changes in the length of the menstrual cycle generally imply disturbances of the hypothalamo-pituitary-ovarian (HPO) axis. In anovulatory DUB with acyclic (irregular) oestrogen production there will be no progesterone withdrawal from oestrogen primed endometrium and so cycles are irregular. Prolonged oestrogen stimulation may cause a build up of endometrium with erratic bleeding as it breaks down and is expelled. This is the rationale for using cyclical progestogens during the second half of the menstrual cycle in order to provoke a regular withdrawal bleed. Continuous progestogen is intended to induce endometrial atrophy and hence to prevent oestrogen-stimulated endometrial proliferation. Progestogens, and oestrogens and progestogens in combination are already widely used in the management of irregular or excessive bleeding due to DUB, but the regime, dose and type of progestogen used varies widely with little consensus about the optimum treatment approach.

OBJECTIVES

To determine the effectiveness and acceptability of progestogens alone, and oestrogens and progestogens in combination in the management of irregular bleeding associated with anovulation.

SEARCH STRATEGY

The search strategy of the Menstrual Disorders Group was used to identify all randomised trials of progestogens alone or in combination with oestrogens in the management of irregular menstrual bleeding associated with anovulation. In addition a search of the Cochrane Controlled Trials Register was undertaken.

SELECTION CRITERIA

All randomised controlled trials of progestogens (via any route) alone or in combination with oestrogens in the treatment of irregular bleeding associated with anovulation.

DATA COLLECTION AND ANALYSIS

Study quality assessment and data extraction were carried out independently by two reviewers. Both reviewers were experts in the content matter.

MAIN RESULTS

No randomised trials were identified which compared progestogens with oestrogens and progestogens in the management of irregular bleeding associated with anovulation. Only one small, non-randomised study compared two progestogen regimes in the management of heavy and irregular bleeding in subjects with confirmed anovulation. One randomised study compared the effects of two progestogens on endometrial histology in subjects with a variety of menstrual symptoms, half of whom had cystic glandular hyperplasia. No studies were found which compared progestogens with oestrogens and progestogens in combination or with placebo in the management of irregular bleeding associated with anovulation.

REVIEWER'S CONCLUSIONS

There is a paucity of randomised studies relating to the use of progestogens and of oestrogens and progestogens in combination in the treatment of irregular bleeding associated with anovulation. Further research is needed to establish the role of these treatments in the management of this common gynaecological problem.

Asthma and thunderstorms: description of an epidemic in general practice in Britain using data from a doctors' deputising service in the UK

OBJECTIVE

To describe the areas affected and the scale of an epidemic of thunderstorm associated asthma on the night of 24/25 June 1994 and to explore the spatial and temporal relationship between the thunderstorm and the associated epidemic.

SETTING

The 29 offices of a deputising service for general practitioners' (GP) out of hours calls (Healthcall). At the time of the storm the deputising service provided out of hours cover for about 8500 out of about 30000 GPs in England, Scotland, and Wales.

METHODS

Patients who phoned the Healthcall offices to request a home visit were categorised as "asthma" or "other causes" based on their presenting complaint. The number of calls on the night of 24/25 June 1994 was compared in areas affected by thunderstorms and areas not affected by thunderstorms and with the night of 17/18 June 1994, when there were no thunderstorms.

RESULTS

A large area of the south and east of England was affected by an epidemic of asthma closely related both temporally and spatially with the thunderstorms on 24/25 June 1994. The pooled Mantel-Haenszel estimate for the risk of asthma in thunderstorm affected areas compared with the control night was 6.36 (95% confidence interval 4.97, 8.32) compared with a value of 1.01 (0.80, 1.27) for those not exposed. Extrapolation suggests about 1500 extra patients were likely to have requested a visit from a GP that night because of epidemic asthma.

CONCLUSIONS

Under certain circumstances thunderstorms are associated with asthma and can affect many patients. Deputising services are a useful source of data for the investigation of epidemics in primary care.

A preliminary investigation of what happens to women complaining of menorrhagia but whose complaint is not substantiated

This observational follow-up study determined the outcome, after a minimum of 3 years' follow up, in women complaining of excessively heavy menses, whose measured blood loss was within the normal range. Of the 81.7% of women followed up, 26% were happy with their periods, 19% were menopausal or taking hormone replacement therapy, 18% were taking a variety of other medical therapies and 28% had undergone surgery. The remainder were pregnant, lactating, or attempting conception. The decision to treat is not solely based on measured blood volume. Some women are intent upon an end to menstruation or have additional indications for surgical intervention. Others are happy with the reassuring knowledge that their menstrual blood loss is normal.