The risk of liver disorders in women prescribed cyproterone acetate in combination with ethinyloestradiol (Dianette): a nested case-control study using the GPRD

PURPOSE

To explore the risk of liver disorders associated with cyproterone acetate combined with ethinyloestradiol (CPA/EE). CPA/EE is licensed in the UK for the treatment of women with acne and hirsutism and is a treatment option for polycystic ovary syndrome (PCOS). It acts as a contraceptive also.

METHODS

Using the General Practice Research Database, we conducted a cohort analysis and case-control study in women aged 15-39 with acne, hirsutism or PCOS to estimate the risk of liver disorders associated with CPA/EE.

RESULTS

Compared with cases exposed to conventional combined oral contraceptives (COCs), the age-adjusted incidence rate ratio for liver disorders in women using CPA/EE was 1.7 (95% CI: 0.9, 3.4) and compared with no use it was 1.5 (95% CI: 0.8, 2.8). In the case-control study, the adjusted odds ratio (OR) for liver disorders in women exposed to CPA/EE was 1.6 (95% CI: 0.7, 3.5) and 0.8 (95% CI: 0.5, 1.3) for exposure to conventional COCs, compared with no use. The risk of liver disorders in women prescribed CPA/EE was not significantly greater than that in women prescribed conventional COCs (OR: 2.1 [95% CI: 0.9, 4.8]).

CONCLUSION

Our results do not indicate an increased risk for liver disorders associated with CPA/EE use in women with acne, hirsutism or PCOS after adjusting for potential confounding. This may be due to lack of statistical power.

The risk of liver damage associated with minocycline: a comparative study

Using the General Practice Research Database, the authors performed (1) a cohort analysis comparing the incidence of liver dysfunction in new users of minocycline with new users of oxytetracycline/tetracycline and (2) a case control study assessing antibiotic exposure in new cases of liver dysfunction and controls without liver dysfunction. In new users, the incidence of liver dysfunction in those exposed to minocycline was 1.04 cases/10,000 exposed person months (EPM) and 0.69 cases/10,000 EPM in those exposed to oxytetracycline/tetracycline (relative risk 1.51 [CI95: 0.63, 3.65]). The risk in both groups was greatest in the first month of use. The adjusted odds ratio (ORadj) of liver dysfunction associated with exposure to minocycline compared with nonuse was 2.10 (CI95: 1.30, 3.40); for oxytetracycline/tetracycline, the ORadj was 1.46 (CI95: 0.81, 2.64); and for exposure to erythromycin, the ORadj was 1.64 (CI95: 0.71, 3.80). The authors thus support a weak association between the use of oral antibiotics and liver dysfunction in patients with acne. The risk associated with exposure to minocycline appears to be very small. The cohort analysis demonstrated that any risk associated with minocycline was not significantly greater than that associated with oxytetracycline/tetracycline exposure.

How do symptoms indicative of BPH progress in real life practice? The UK experience

OBJECTIVE

Lower urinary tract symptoms (LUTS) are usually, but not exclusively associated with benign prostatic hyperplasia (BPH). Using a population identified from the UK General Practice Research Database (GPRD), we describe the changes in the management of LUTS/BPH and assess the effectiveness of medical therapy between 1992 and 1998.

METHODS

61,364 men with LUTS/BPH and without a record of prostatic cancer were identified on the database. 14,195 were treated with an alpha1-blocker or finasteride. Treatment failure was defined as prostatic surgery, catheterisation or a switch in medical therapy.

RESULTS

LUTS/BPH incidence increased linearly from the age of 45 to 85 years (r2 = 0.992) and prevalence increased from 3.5% to 35% for men in their late 40s and 80s respectively. Prostatectomy rates increased linearly from the age of 50 to 80 years (r2 = 0.984). Between 1992 and 1998, total treated-patient time had increased 3-fold, patients have been medically treated earlier and have increasingly been prescribed the LUTS/BPH-specific treatments finasteride, tamsulosin and alfuzosin in comparison to older treatments (indoramin, prazosin). In parallel, there has been a progressive increase in the interval between first diagnosis and prostatic surgery, and this interval is significantly longer for medically treated patients than those receiving no medical therapy. The intervals between the start and failure of medical therapy were significantly shorter for patients receiving indoramin and prazosin than for those receiving specific LUTS/BPH treatments.

CONCLUSIONS

Between 1992 and 1998 there has been a significant lengthening of the period between first diagnosis of LUTS/BPH and surgery. This postponement of surgery is associated with earlier treatment and the increased use of specific LUTS/BPH treatments that appear more effective than older products in delaying treatment failure.

Lower urinary tract symptoms suggestive of benign prostatic obstruction--Triumph: the role of general practice databases

The Triumph project aims to document the current management of lower urinary tract symptoms (LUTS) suggestive of benign prostatic hyperplasia (BPH) in general practice and to assess the effectiveness of the initial treatment options used. The first phase of the project will consider existing data sources in primary care. A patient's medical record will contain most, if not all, clinically relevant information, and databases combining the records from a network of computerised general practices can provide longitudinal data for complete populations, linking prescribing records to clinical information on disease progression and outcomes for individual patients. Database research can provide rapid information and offers the ability to conduct studies on a scale that would previously have been prohibited by both time and expense. Within the Triumph project, the THALES, General Practice Research Database (GPRD) and Integrated Primary Care Information (IPCI) databases are, or will be, used to examine the current management of LUTS/BPH in France, the UK and the Netherlands respectively. Preliminary results from the UK General Practice Research Database (GPRD) showed that LUTS/BPH incidence increased linearly from the ages of 45 to 85 years (r(2) = 0.992) and prevalence increased from 3.5% to 35% for men in their late 40s and 80s respectively. With treatment failure defined as a change to another medical therapy, catheterisation or prostatic surgery, and accounting for age and year variation, patients receiving the older alpha(1)-blockers (indoramin and prazosin) appeared to fail significantly earlier than those receiving finasteride. There was no significant difference between finasteride and the newer alpha(1)-blockers (tamsulosin, alfuzosin, terazosin and doxazosin). Patterns of changes between products from the THALES database in France were broadly similar to those seen in the UK.

Evaluating adverse cardiovascular effects of drug treatment for benign prostatic hyperplasia (BPH): methodological considerations

When studying the effects of drug exposure in diseases with a long asymptomatic clinical course, exposure classification may be biased by the gradually developing "visibility" of the disease. Benign prostatic hyperplasia (BPH) is such a disease. We found that cardiovascular morbidity is two times more prevalent in patients starting drug treatment for BPH when compared to age-matched population controls. This resulted in a difference of cardiovascular prognostic factors between the exposed and non-exposed. This feature can jeopardize the validity of non-randomized comparisons of drug effects. Moreover, the existence of non-treatment strategies, disease under-reporting, and an elderly population with a high baseline risk of experiencing (cardiovascular) outcome events were encountered as methodological problems. When studying adverse cardiovascular effects in patients using BPH products in a non-randomized fashion, an important question is whether we can measure in the database all relevant prognostic factors and use the information for statistical adjustment. This question is an important challenge to observational research and once again stresses the need for control of possible biases in choosing an appropriate study design.

Venous thromboembolism in pregnancy and the puerperium: incidence and additional risk factors from a London perinatal database

OBJECTIVE

To determine the incidence of venous thromboembolism in pregnancy and the puerperium and to identify risk factors for pregnancy-related venous thromboembolism.

DESIGN

Cohort study and case-control study.

SETTING

London, UK.

POPULATION

395,335 women with live births or pregnancies of 24 or more weeks of gestation between 1988 and 1997.

METHODS

Data extraction from the St Mary's Maternity Information System database. Random sample of 5% for case-control study.

MAIN OUTCOME MEASURES

Incidence of venous thromboembolism; odds ratios for variables associated with venous thromboembolism.

RESULTS

The incidence of venous thromboembolism was 85/100,000 maternities. There were approximately twice as many postpartum as antepartum events. Blood group A, multiple pregnancy, caesarean section, cardiac disease, delivery at gestational age of < 36 weeks, a body mass index of > or = 25, or more and maternal age of 35 or over were all found to increase incidence of venous thromboembolism.

CONCLUSIONS

Although venous thromboembolism is the leading cause of maternal deaths in the UK, it is still a rare event. Most of these events are deep vein thromboses occurring in the postpartum period. Antenatally multiple birth is an important risk factor. Postnatally women who have had a caesarean section, premature delivery or history of cardiac disease should be assessed carefully for venous thromboembolism.

The effects of age, body mass index, smoking and general health on the risk of venous thromboembolism in users of combined oral contraceptives

OBJECTIVES

To investigate the factors associated with idiopathic venous thromboembolism in combined oral contraceptive users and to estimate the crude and age-specific incidence rates ofidiopathic venous thromboembolism among this population.

METHODS

The UK MediPlus Database and the General Practice Research Database were searched to identify women with evidence of venous thromboembolism while exposed to combined oral contraceptives. Cohort and nested case-control studies were carried out using the same methodology on both databases. We conducted a meta-analysis using the individual data for the cases and controls from the two case-control studies to identify factors associated with idiopathic venous thromboembolism in women using combined oral contraceptives.

RESULTS

The incidence rate of idiopathic venous thromboembolism among oral contraceptive users was 39.4 per 100,000 exposed woman-years. The age-specific incidence rates were found to rise sharply after the age of 39 years. Factors identified as being significantly associated with idiopathic venous thromboembolism in women using combined oral contraceptives were: body mass index of 25 kg/m2 and over, the association rising dramatically in women with a body mass index of 35 kg/m2 or more; smoking; general ill health; and asthma.

CONCLUSION

We believe that, before prescribing combined oral contraceptives, the venous as well as the arterial factors need to be considered and, in addition, age, obesity and smoking are all relevant when assessing an individual patient's risk.

Liver damage associated with minocycline use in acne: a systematic review of the published literature and pharmacovigilance data

OBJECTIVE

Minocycline is an antibacterial drug used in the treatment of acne. Concern has been expressed over the possibility of severe adverse reactions to minocycline, including hepatitis. This study set out to identify and characterise reported cases of hepatotoxicity associated with the use of minocycline.

METHODS

A systematic review of the literature including a search of computerised databases and analysis of data from the Uppsala Monitoring Centre (WHO Collaborating Centre for International Drug Monitoring) was conducted. The review involved a search for original case reports involving liver damage in people using minocycline. Patients taking minocycline for reasons other than acne or those given intravenous minocycline were excluded. The search strategy involved an enquiry of computerised databases and a search for secondary references. Cases were then classified appropriately.

RESULTS

65 reported cases of hepatitis or liver damage in association with minocycline from either case reports or case series were identified from the literature review. 58% of cases occurred in females and 94% were aged under 40 years. For 20 case reports there was insufficient information to classify the type of event, but for the remaining 45, 2 types of hepatic reaction were recognised: autoimmune hepatitis associated with lupus-like symptoms occurring after a median duration of exposure to minocycline of 365 days in females (n = 20) and 730 days in males (n = 9), hypersensitivity reaction associated with eosinophilia and exfoliative dermatitis occurring within 35 days of therapy (n = 16). Reports to the WHO of hepatic adverse drug reactions associated with minocycline accounted for 6% (493) of all minocycline-related adverse drug reactions (8025). The pattern of distribution in relation to exposure demonstrated 2 groups, similar to that described by the case reports.

CONCLUSIONS

Severe cases of minocycline-associated hepatotoxicity appear to be a hypersensitivity reaction and occur within a few weeks of commencing therapy. An autoimmune hepatitis usually presents after exposure to minocycline of a year or more, is more common in women and is sometimes associated with lupus-like symptoms.

Effect of 1995 pill scare on rates of venous thromboembolism among women taking combined oral contraceptives: analysis of general practice research database

OBJECTIVE

To compare the incidence of venous thromboembolism among women taking combined oral contraceptives before and after the October 1995 pill scare.

DESIGN

Analysis of General Practice Research Database.

SETTING

United Kingdom, January 1993 to December 1998.

SUBJECTS

Women aged 15-49 taking combined oral contraceptives.

MAIN OUTCOME MEASURES

Incidence of venous thromboembolism.

RESULTS

Use of so called "third generation" combined oral contraceptives fell from 53% during January 1993 to October 1995 to 14% during November 1995 to December 1998. There was no significant change in the incidence of venous thromboembolism between the two periods after age was adjusted for (incidence ratio 1.04, 95% confidence interval 0.78 to 1.39).

CONCLUSIONS

The findings are not compatible with the assertion that third generation oral contraceptives are associated with a twofold increase in risk of venous thromboembolism compared with older progestogens.

The treatment of depression in UK general practice: selective serotonin reuptake inhibitors and tricyclic antidepressants compared

BACKGROUND

Antidepressants are commonly prescribed by general practitioners as treatment for depression. Controversy exists as to the effectiveness in everyday use of the older tricyclic antidepressants (TCAs) when compared to the newer selective serotonin reuptake inhibitors (SSRIs).

AIM

To investigate the patterns of current prescribing of antidepressants for the treatment of depression and compare TCAs with the newer SSRIs.

METHOD

The study population was patients attending 151 computerised general practices from throughout the United Kingdom between 1991 and 1996. Patients with new prescriptions for antidepressants and a diagnosis of depression were identified. Age and gender distributions, prescribed doses and drop-out rates were investigated.

RESULTS

During the study period 9.8% of patients received a prescription for an antidepressant, there was a 40% increase in the prescribing rate of TCAs and a 460% increase in SSRI prescribing. TCAs were initially prescribed in sub-therapeutic doses. More than 50% of patients ceased taking their antidepressants within 6 weeks of starting treatment. Fluoxetine and paroxetine were more likely to be prescribed for a therapeutic period than were other antidepressants.

CONCLUSIONS

General practitioners should prescribe a therapeutic dose of antidepressant for a recognised therapeutic period to ensure that patients with depression receive the most effective treatment.

Medical therapy for benign prostatic hyperplasia: a review of the literature

OBJECTIVE

To review the existing evidence regarding the efficacy and safety of medical therapy for lower urinary tract symptoms (LUTS) indicative of benign prostatic hyperplasia (BPH). To assess randomised controlled trials investigating the six alpha-adrenergic receptor antagonists (alpha-blockers), prazosin, alfuzosin, indoramin, terazosin, doxazosin, and tamsulosin, that benefit patients by relaxing prostatic smooth muscle, and the anti-androgen, finasteride, that mediates its more long-term benefits by reducing prostate size.

RESULTS

This review suggests that both classes of drug offer significant improvement in criteria used to evaluate symptomatic BPH and can be effective whilst being acceptably safe. Furthermore, the therapeutic efficacy of all contemporary alpha-blockers appear similar, both in terms of symptom relief and urodynamic improvements. Randomised controlled trials have additionally demonstrated that finasteride therapy can provide improvement in terms of quality of life indices, prostate volume, and risks of progressing to acute urinary retention or prostatic surgery. While alpha-blockers have a rapid onset of action, likely to produce a therapeutic result within weeks, regardless of whether prostatic enlargement or bladder outlet obstruction is present, finasteride appears to be effective for more long-term therapy for up to 4 years, but only in alleviating symptoms when they are associated with a significantly large prostate. Neither finasteride nor the alpha(1a)-receptor-selective blocker, tamsulosin, are associated with the lowering of blood pressure and incidence of cardiovascular side effects that are apparent with other less selective alpha-blocker therapies such as dizziness and postural hypertension. They are, however, both associated with an increased risk of sexual dysfunction, albeit less than those associated with surgical intervention. Whereas tamsulosin is associated only with ejaculatory dysfunction, finasteride is additionally linked to decreased libido and impotence.

A comparison of the risks of venous thromboembolic disease in association with different combined oral contraceptives

AIMS

In October 1995 in response to the results of three studies, the Committee on the Safety of Medicines advised doctors and pharmacists that oral contraceptives containing desogestrel (DSG) and gestodene (GST) were associated with around a two-fold increase in the risk of thromboembolism compared with those containing other progestogens. The objective of this study was to estimate the risk of idiopathic venous thromboembolic disease (VTE) in users of combined oral contraceptives (COCs), to compare the risk between formulations and to examine the effect of using age banding as opposed to matching by exact year of birth.

METHODS

A nested case control study was conducted using the General Practice Research Database. Women with a VTE event recorded between 1992 and 1997, who were treated with an anticoagulant, from consideration of their prescription records were likely to have been using a COC prescription on the day of the event and also had no exclusion factors, were deemed cases. For comparison with the previous studies, two nested case control studies were undertaken. Study 1 used controls matched by practice and year of birth. Study 2 used controls matched by practice and within 5 years age bands.

RESULTS

We found an incidence of idiopathic VTE amongst users of combined oral contraceptives of 3.8 per 10 000 exposed women years. Incidence rates increased markedly after 35 years of age. The nested case-control study using controls matched by year of birth showed no significant difference in risk between the major COC formulations. With levonorgestrel (LNG) 150 microgram and ethinyloestradiol (EE) 30 microgram as the reference, the adjusted ORs for GST 75 microgram and EE 30 microgram was 1.3 (95% CI 0.8, 2.1), for DSG 150 microgram and EE 30 microgram it was 1.0 (95% CI 0.7, 1.7) and for DSG 150 microgram and EE 20 microgram it was 0.8 (95% CI 0.4, 1.6). Using less rigorous matching criteria, matching controls to cases within 5 years age bands, the ORs increased. When a mixed group of COCs, characterized by having LNG as the progestogen component was used as the reference category, there was an elevation in the ORs for the newer products. We found a significant association between idiopathic VTE and current smoking (OR 2.0 (1.4, 2.7)), BMI over 35 (OR 3.8 (1.8, 8.0)) and asthma (OR 1.9 (1.3, 2.9)). The OR for women who had proxy evidence of general ill health (indicated by the number of prescriptions issued) was 2.2 (1.7, 3.7).

CONCLUSIONS

The results of this study indicate that a number of the characteristics of the women taking COCs affect the risk of VTE. There is no evidence to support the hypothesis that there is any difference in risk between COC formulations containing under 50 microg ethinyloestradiol.

Validation of the diagnosis of venous thromboembolism in general practice database studies

AIMS

The study was conducted to determine whether the method for selecting cases of venous thromboembolism (VTE) from general practice databases significantly affected the findings of an epidemiological study.

METHODS

Cases of VTE were identified from the UK General Practice Research Database (GPRD) by searching for codes for deep vein thrombosis (DVT) and pulmonary embolism (PE). These had to be supported by evidence of anticoagulation and be exposed to a combined oral contraceptive (COC) at the time of the event. Additional information about the event was sought from general practitioners who were requested to complete a questionnaire and to supply anonymised copies of hospital letters and discharge summaries.

RESULTS

Of the 285 cases identified from the GPRD, additional information was available for 177 VTE events. This information showed that 84% of those events were supported by hospital investigations or a death certificate. Using only verified cases, rather than all GPRD identified events, did not alter the results of the epidemiological study.

CONCLUSIONS

The GPRD provides information of sufficiently high quality to allow valid epidemiological research of VTE events. Excluding cases without a database record of hospital admission would lead to valid events being overlooked, and an under-estimate of the disease incidence.

Oral contraceptives and venous thromboembolic disease. Analyses of the UK General Practice Research Database and the UK Mediplus database

The results of three independent studies of venous thromboembolic disease (VTE) and oral contraceptives are reviewed together with two further cohort/case-control studies which we conducted using the MediPlus and General Practice Research Database (GPRD) databases. These latter studies jointly involved 395 cases and uniquely examined the association between VTE and individual combined oral contraceptive (COC) formulations. The two studies yielded very similar results. Crude incidence rates for idiopathic VTE of 4.6 and 3.8 were found per 10,000 exposed woman-years (EWY), in the MediPlus and GPRD studies respectively. Incidence rates increased markedly with age, and in both databases the rates amongst users of levonorgestrel products were lower than those amongst users of desogestrel and gestodene products. A case fatality rate of 3% and a mortality rate of 10 per million EWY were estimated. Odds ratios (OR) were calculated for confounding variables and different COC formulations. Both database studies indicated an excess of current smokers and women with high body mass indices amongst cases. There were significantly more cases with asthma in the GPRD study and cases who had been using their COC for less than a year. No statistically significant differences between COC formulations were found in the analyses where controls were matched to cases by practice and year of birth in both the MediPlus and GPRD studies. In the GPRD study we also ran a study where controls were matched by practice and within 5 year age bands. In this study the OR were consistently higher for the newer or 'third generation' products than when controls were matched by year of birth. However only the acne formulation/OC containing cyproterone acetate and 35 microg ethinyloestradiol yielded a significant OR of 2.3. It may be concluded that improvements in prescribing are paramount as the results strongly indicate that overweight women and those who smoke are at a greater risk of VTE. Further study is required to elucidate the possibility that asthma or its treatment may predispose to VTE, alone or in combination with other risk factors. However, neither the MediPlus nor GPRD studies indicate that any one COC formulation poses a greater risk of VTE than another.

Venous thromboembolic disease and combined oral contraceptives: A re-analysis of the MediPlus database

In October 1995 the Committee on Safety of Medicines advised UK doctors and pharmacists that oral contraceptives containing desogestrel and gestodene were associated with double the risk of venous thromboembolic events (VTE) compared to pills containing other progestogens. In 1997 data was analysed from the MediPlus database of UK general practitioner records, which reported odds ratios for desogestrel and gestodene lower than that for levonorgestrel. Here the results of a more stringent nested case control analysis on the MediPlus database are reported. The study was larger and cases were verified. A crude incidence of idiopathic VTE was found amongst users of combined oral contraceptives of 4.6 per 10 000 exposed women years. Using levonorgestrel 150 microg + ethinyloestradiol 30 microg as reference, non-significant odds ratios of 1.1 (0.5-2.6) for desogestrel 150 microg + ethinyloestradiol 30 microg and 1.1 (0.5-2.4) for gestodene 75 microg + ethinyloestradiol 30 microg were found. The results of this study show no significant difference in risk between different formulations of combined oral contraceptive.

Oral contraceptives and venous thromboembolic disease: the findings from database studies in the United Kingdom and Germany

OBJECTIVE

Three research articles published in late 1995 and early 1996 suggested that oral contraceptives containing either of the newer progestogens (gestodene or desogestrel) could be associated with an increased risk of venous thromboembolism. During the months after the initial publications, the results have been scrutinized with great care and further studies have been published. The findings of 2 recent database studies, 1 in the United Kingdom and 1 in Germany, are presented in this article.

PATTERNS OF USE

The average age of users of combined oral contraceptives in Germany was 27 years, compared with 26 years in the United Kingdom. In Germany the use of gestodene-based products was lower than that in the United Kingdom. In the United Kingdom the users of desogestrel with 20 microg ethinyl estradiol (Mercilon) were older than the users of desogestrel with 30 microg ethinyl estradiol (Marvelon).

CRUDE INCIDENCE

The crude incidence of venous thromboembolism in the UK study was 4.1 cases/10,000 woman-y exposure to combined oral contraceptives. In Germany it was 4.2 cases/10,000 woman-y. In Germany the rates among users of second-generation combined oral contraceptives were higher than those among users of third-generation products. The reverse was the case in the United Kingdom. In the United Kingdom the crude incidence rates were higher for the 20 microg estrogen desogestrel product than for the 30 microg product. CASE-CONTROL ANALYSIS: The adjusted odds ratios in the UK study did not show significant increases for desogestrel or gestodene compared with levonorgestrel products. There were inconsistencies in the results among centers in the 2 international studies (the World Health Organization and Transnational studies). In both there was a consistent inverse dose-response relationship with estrogen in all centers.

CONCLUSION

The limitations of the observational studies are such that the hypothesis that the newer progestogens are more likely to cause venous thromboembolism cannot be proved.

The risks of venous thromboembolic disease among German women using oral contraceptives: a database study

This study investigated the risk of venous thromboembolic disease (VTE) between second and third generation combined oral contraceptives, using the German MediPlus database of patient records. Women studied included 42 patients between the ages of 18 and 49 years, with a diagnosis of VTE treated with an anticoagulant, who were exposed to an oral contraceptive (OC). Four controls per patient (168), matched by year of birth and exposure to an OC on the even day, were identified. More women were users of second generation than third generation OC, and none were using progestogen-only pills. There was no significant difference between patients and control subjects with respect to the type of OC used on the event day (unadjusted odds ratio for third versus second generation users was 0.77; 95% confidence interval [CI] 0.38-1.57). There was no significant age difference between second and third generation users among patients or control subjects. Between January 1 and the event date, there was no significant difference between the patients and control subjects in terms of the number of oral contraceptive prescriptions, number of consultations for psychotherapeutic complaints, or mixed physical and psychotherapeutic consultations; however, patients did demonstrate significantly more consultations for purely physical complaints compared with control subjects (p < 0.0001). There were no significant consultation differences between patients with pulmonary emboli (n = 6) and other VTE patients (n = 36). No significant differences with respect to VTE risk between users of second and third generation oral contraceptives were found in this study. Consultations (physical) for patients were higher than for control subjects before the VTE event. If consultation rate relates to the general health status of a person, this might indicate that VTE risk is higher among women of poorer health, but that this is not related to the type of progestogen in the oral contraceptive that they use.

Mortality from venous thromboembolism among young women in Europe: no evidence for any effect of third generation oral contraceptives

STUDY OBJECTIVE

To investigate whether there has been an increase of venous thromboembolism (VTE) mortality in European countries, concurrent with the replacement of second generation by third generation combined oral contraceptives (COCs). Such an increase has been predicted, and reportedly detected, because published studies have detected an increased incidence of VTE associated with third generation rather than second generation COC use.

DESIGN

Data were collected on population and annual VTE mortality in women 15-34 and 35-49 years old, and on second and third generation COC sales, from 1981 to 1994 in 13 European countries. Data from the seven most populous countries were analysed by linear regression of annual VTE mortality, in the 15-34 and 15-49 age groups, with respect to calculated total and third generation COC use rates, and the regression coefficients used to estimate mortality differences between second generation users and non-users and between third and second generation users, respectively.

MAIN RESULTS

The estimated mortality differences in all seven countries had confidence intervals wide enough to contain both zero and the excess mortalities expected from the results of published studies. This was true both for the mortality difference between third and second generation COC users and for that between second generation users and COC non-users.

CONCLUSIONS

Mortality differences of the size expected from the published studies cannot be measured using annual national VTE mortality and COC sales data alone, because of residual interannual variation in VTE mortality, and possibly confounding between rising third generation market share and total COC use.

Population-based study of risk of venous thromboembolism associated with various oral contraceptives

BACKGROUND

Four studies published since December, 1995, reported that the incidence of venous thromboembolism (VTE) was higher in women who used oral contraceptives (OCs) containing the third-generation progestagens gestodene or desogestrel than in users of OCs containing second-generation progestagens. However, confounding and bias in the design of these studies may have affected the findings. The aim of our study was to re-examine the association between risk of VTE and OC use with a different study design and analysis to avoid some of the bias and confounding of the earlier studies.

METHODS

We used computer records of patients from 143 general practices in the UK. The study was based on the medical records of about 540,000 women born between 1941 and 1981. All women who had a recorded diagnosis of deep-vein thrombosis, venous thrombosis not otherwise specified, or pulmonary embolus during the study period, and who had been treated with an anticoagulant were identified as potential cases of VTE. We did a cohort analysis to estimate and compare incidence of VTE in users of the main OC preparations, and a nested case-control study to calculate the odds ratios of VTE associated with use of different types of OC, after adjustment for potential confounding factors. In the case-control study, we matched cases to controls by exact year of birth, practice, and current use of OCs. We used a multiple logistic regression model that included body-mass index, number of cycles, change in type of OC prescribed within 3 months of the event, previous pregnancy, and concurrent disease.

FINDINGS

85 women met the inclusion criteria for VTE, two of whom were users of progestagen-only OCs. Of the 83 cases of VTE associated with use of combined OCs, 43 were recorded as deep-vein thrombosis, 35 as pulmonary thrombosis, and five as venous thrombosis not otherwise specified. The crude rate of VTE per 10,000 woman-years was 4.10 in current users of any OC, 3.10 in users of second-generation OCs, and 4.96 in users of third-generation preparations. After adjustment for age, the rate ratio of VTE in users of third-generation relative to second-generation OCs was 1.68 (95% CI 1.04-2.75). Logistic regression showed no significant difference in the risk of VTE between users of third-generation and second-generation OCs. Among users of third-generation progestagens, the risk of VTE was higher in users of desogestrel with 20 g ethinyloestradiol than in users of gestodene or desogestrel with 30 g ethinyloestradiol. With all second-generation OCs as the reference, the odds ratios for VTE were 3.49 (1.21-10.12) for desogestrel plus 20 g ethinyloestradiol and 1.18 (0.66-2.17) for the other third-generation progestagens.

INTERPRETATION

The previously reported increase in odds ratio associated with third-generation OCs when compared with second-generation products is likely to have been the result of residual confounding by age. The increased odds ratio associated with products containing 20 micrograms ethinyloestradiol and desogestrel compared with the 30 micrograms product is biologically implausible, and is likely to be the result of preferential prescribing and, thus, confounding.

Platelet 5-hydroxytryptamine is decreased in a preliminary group of depressed patients receiving the 5-hydroxytryptamine re-uptake inhibiting drug fluoxetine

1. In view of the importance of 5-hydroxytryptamine in coronary thrombosis, we wanted to know whether a potentially protective decrease in platelet 5-hydroxytryptamine could be achieved by treatment with an inhibitor of 5-hydroxytryptamine uptake, fluoxetine. 2. We studied 15 patients treated for psychiatric indications with fluoxetine, and compared the findings with those obtained with blood from 18 patients treated with amitriptyline and 13 controls previously treated for affective disorders. 3. Platelet-rich plasma 5-hydroxytryptamine levels were significantly decreased in the fluoxetine group (P < 0.005) but not in the amitriptyline group compared with the control group. 4. Collagen-induced aggregation in whole blood anticoagulated with hirudin was measured by sequential single platelet counting. The contribution of 5-hydroxytryptamine was assessed from the effect of adding the 5-hydroxytryptamine specific antagonist ICI 170809. This contribution was significantly decreased in the fluoxetine group but not in the amitriptyline group compared with the control group. 5. It is concluded that platelet 5-hydroxytryptamine is indeed decreased by fluoxetine, and we would predict a protective effect of fluoxetine against coronary thrombosis.

Utilization patterns of oral contraceptives in UK general practice

The aim of this article was to analyze and compare recent oral contraceptive utilization patterns in UK general practice. The database comprised at least 12 months of medical records during 1990-1991 from 693-705 women aged 14-45 years registered with 398 practices. The database was searched for OC utilization patterns with emphasis on differences between combined OCs containing levonorgestrel (LNG), desogestrel (DSG), or gestodene (GSD). Women using OCs with LNG were older, more likely to be long-term users, and less likely to be starters or switchers than women using OCs with DSG or GSD. Use patterns of triphasic LNG did not differ markedly from that of monophasic LNG-containing OCs. Use of Schering PC4 a postcoital preparation peaked among women < 20 years, whereas progestogen-only pills were prescribed mainly to women > 30 years. The different utilization patterns between women using LNG-containing OCs and those using OCs containing DSG or GSD should be taken into account when making comparisons of the incidences of side effects.

Oral contraceptive switching patterns in the United Kingdom: an important potential confounding variable in studies of venous thromboembolism

OBJECTIVE

To investigate whether patients changing from their current oral contraceptive (OC) are preferentially switched to third-generation preparations.

METHOD

The database comprised 12 months of medical records generated during 1990-91 from 693,705 patients and 153,687 OC users aged 14-45 years registered with 398 practices in the United Kingdom. Subjects who switched OC preparations were identified.

RESULTS

A total of 16,197 women (10.5%) switched OC preparations at least once during the study period. There was a statistically significant net switching from second-generation OCs to third generation OCs with a ratio of 1.19 (95% CI, 1.12-1.26). This switching behavior took place in both younger (< 25 years) and older (> or = 25 years) OC users. In addition, a significant net switching was observed from progestogen-only pills to both second- and third-generation OCs. This was more pronounced in women > or = 25 years.

CONCLUSION

Bias resulting from preferential switching of women from second-generation to third-generation OCs may have influenced the results of recently published studies on combined OCs and the risk of venous thromboembolism. Studies of venous thromboembolism in women using OCs should either restrict from the study women who have switched preparations or should include switching as a variable in any analysis.

Psychological reactions of drivers to railway suicide

Around 90 London Underground train drivers experience a person jumping or falling in front of their train each year. The majority of these incidents are suicides or attempted suicides. 76 drivers were interviewed in order to assess the range of responses to these incidents. The following psychometric instruments were used: Present State Examination (PSE9); Post-Traumatic Stress Disorder (PTSD) Interview; General Health Questionnaire (GHQ-28); Impact of Events Scale (IES); Post-Traumatic Symptom Scale; Recent Difficulties/Events scale; Perceived Stress Scale and Eysenck Personality Questionnaire (EPQ). When interviewed 1 month after the incident 13 (17.11%) drivers presented with PTSD. Diagnoses other than PTSD e.g. neurotic depression and phobic state were present in 24 (31.58%) drivers (including 12 of the 13 PTSD cases who had one additional diagnosis). On the basis of diagnoses three groups were identified: Group 1 drivers had PTSD and in most cases an additional PSE9 diagnosis; Group 2 drivers had a PSE9 diagnosis only; Group 3 drivers were not cases. 56 drivers were again interviewed 6 months after the incident to assess duration of caseness and/or symptoms and to identify any cases of delayed onset. Two drivers were still cases at 6 months (neurotic depression and phobic state), no driver presented with PTSD at 6 months. At 6 months there was a significant drop in symptom scores compared with measures taken at 1 month. These results suggest that although approximately one-third of drivers suffered a severe psychological reaction following a railway suicide, when interviewed again 6 months after the incident most drivers reported a marked reduction in symptoms.

The epidemiology of suicide on the London Underground

A database containing details of every incident of suicidal behaviour on the London Underground railway system between 1940 and 1990 was assembled from the records of London Underground Ltd and the British Transport Police. The total number of cases was 3240. The mean annual number of suicidal acts on the London Underground system increased from 36.1 (1940-1949) to 94.1 (1980-1989). There were significantly fewer incidents on Sundays than on the other days of the week and the daily rate was highest in the spring. 64% of incidents involved males and the peak age group for both sexes was 25-34 yr. Suicide verdicts were returned for a greater proportion of women than men. Overall case fatality was 55%. However, case fatality rates differed between stations, environmental factors appearing to influence survival. Possible strategies to prevent railway suicides and reduce the lethality of this method are discussed.

A follow-up study of attempted railway suicides

This paper reports the subsequent mortality of 94 persons who attempted suicide by jumping in front of London Underground trains between 1977 and 1979. The follow-up period was 10 yr. Despite the apparent seriousness of the method, completion of suicide was not found to be higher than in previous studies of attempted suicide by other methods. By the end of the follow-up period 18 persons had died, nine of natural causes. Coroners' inquests were held for the unnatural deaths. Seven verdicts of suicide and two of accidental death were recorded. Of the nine unnatural deaths four were from multiple injuries, three from drowning, one from asphyxia and one from acute narcotic poisoning. All four multiple injury deaths were women, three of these were from repeated incidents involving London Underground trains. The time interval between the index attempt and eventual death for the suicide/accident group ranged from 1 day to 43 months. For ethical reasons it was not possible to follow-up attempted suicides who were presumed to have remained alive.

Is the money following the clients with learning disabilities?

For the past decade patients with learning disabilities living in long stay mental handicap hospitals have been resettled in the community. Local authorities have also taken on the care of new patients who would once have been long stay residents. The imperfect data that are available suggest that in England about half the residents in mental handicap hospitals in 1981 are now the responsibility of local authorities; the figures for Wales and Northern Ireland are 38% and 33%. Data on revenue suggest that the savings to the health service are much less--perhaps 9% in Northern Ireland and 3.6% in England, although there have also been capital gains through the sale of hospitals. Existing methods of transferring money from health to local authorities--joint finance and "dowries" for individual patients--do not seem adequately to have compensated local authorities. Moreover, as patients still to be transferred are more severely disabled local authorities will require larger sums--about 26 000 pounds per patient per year plus 39 200 pounds in capital. If the government chooses not to transfer these resources from health authorities it will be switching funds away from learning disabled people to other care groups.

Suicidal acts on metro systems: an international perspective

Suicide is a problem experienced by railway networks worldwide. The epidemiology of this method of suicide has not been described in any detail. To investigate the characteristic features of railway suicide, data were gathered from 23 metro systems around the world. The similarities in the nature of this problem across systems were striking. Universally the victims were young (aged less than 40 years); most incidents involved men; case fatality was generally less than 60%; there was no consistent seasonal variation in incidence; the peak time of day for incidents was 1000-1200; proximity to psychiatric institutions was possibly a risk factor. This method of suicide may be prevented by environmental modification of the railway system. Strategies for reducing the opportunities for suicide on railways are discussed.

Operative survival and 40 year follow up of surgical repair of aortic coarctation

OBJECTIVE

To study early and late mortality after surgical correction of coarctation of the aorta.

DESIGN

Data on 223 patients operated on at the Westminster Hospital, London, between 1946 and 1981, were collected and updated by questionnaire.

PARTICIPANTS

All 223 patients recorded as undergoing operation for aortic coarctation up to the end of 1981. Fifteen of 197 survivors were lost to follow up; most of them were patients from overseas.

OUTCOME AND RESULTS

The early mortality (within one month of operation) was 12% overall, 2.6% for elective surgery, and 0% for the 77 patients undergoing surgery since 1968. Survivors were followed up for a total of 3288 patient years; in 27 follow up lasted more than 30 years. In a few it reached 40 years. Twenty two patients died during this period, 18 from causes that could be attributed to coarctation or its repair. Mortality was highest more than 20 years after the operation.

CONCLUSION

Repair increased life expectancy in patients with aortic coarctation. Late problems caused by persistent hypertension or recoarctation became apparent in long term survivors. The increased risk of late mortality associated with the duration of preoperative hypertension was not statistically significant. There were no deaths from cerebrovascular accidents. (In an earlier necropsy series cerebrovascular accidents accounted for 11.8% of deaths.) The incidence of deaths from aneurysms resembled that in the earlier necropsy series.

Models for forecasting hospital bed requirements in the acute sector

STUDY OBJECTIVE

The aim was to evaluate the current approach to forecasting hospital bed requirements.

DESIGN

The study was a time series and regression analysis. The time series for mean duration of stay for general surgery in the age group 15-44 years (1969-1982) was used in the evaluation of different methods of forecasting future values of mean duration of stay and its subsequent use in the formation of hospital bed requirements.

RESULTS

It has been suggested that the simple trend fitting approach suffers from model specification error and imposes unjustified restrictions on the data. Time series approach (Box-Jenkins method) was shown to be a more appropriate way of modelling the data.

CONCLUSION

The simple trend fitting approach is inferior to the time series approach in modelling hospital bed requirements.

Why do fatal overdose rates vary between antidepressants?

Age specific death rates for poisoning with different antidepressant drugs, based on mortality statistics and the numbers of prescriptions dispensed, were calculated for England and Wales 1979-1985. There are marked variations in mortality associated with different drugs; the highest rates are found with amitriptyline and dothiepin whereas the lowest were associated with mianserin and clomipramine. For all drugs considered, the calculated mortality rates for the over 65 year olds, though still substantial, were lower than those in patients under 65 years of age, probably because of a diminished detection rate of poisoning in this older age group. A high proportion of the fatal overdoses implicating amitriptyline and dothiepin involved more than one substance. The rank order of mortality rates from antidepressants was identical in the different age groups. The implications of these findings are discussed. It is concluded that the variations in mortality rates are mostly due to variations in the inherent toxicity of the drugs (particularly their cardiovascular effects) and only in part due to possible differences in compliance. It is suggested that when antidepressant drugs are prescribed, the risk of death from overdose should be taken into account. Tricyclic drugs, particularly amitriptyline, dothiepin, doxepin, trimipramine and maprotiline, should be avoided in patients at risk of suicide, whatever the age of the patient.

Assessing the epidemiology of suicide and parasuicide

Suicide is a rare phenomenon – in most countries, it explains between 0.5 and 1% of all deaths – no more than 15 per 100 000 population. Although rates increase with age, its impact on the total mortality of the young is greater than its impact on the elderly. Despite its rarity, the subject has attracted, and continues to attract, wide interest among academics and popular writers.

Suicide in England and Wales: an analysis of 100 years, 1876-1975

The variations in suicide mortality in England and Wales over a 100-year period (1876-1975) are explained by the development of a descriptive model. The model used in a stepwise linear regression using 5 variables including toxic gas production. The variables give a good description of the observed changes in suicide mortality. The limitations of the method and the data are discussed. Despite the limitations of the method, it can be concluded that toxic gas production affected total suicide mortality.

Suicide by different methods

The annual numbers of suicide deaths for the past 100 years by different methods in England and Wales are presented. It is shown that the numbers of deaths by 2 methods, domestic gas poisoning and poisoning by solid or liquid substances, vary independently of all other methods. It is concluded that inferences as to cause drawn from aggregated data should be viewed with great caution.

Suicide mortality in Greater London: changes during the past 25 years

Suicide mortality in the area now administered by the Greater London Council was assessed for three five-year periods 1949-1953, 1959-63, and 1969-73. For each of the periods the standard mortality ratio (SMR) for suicide in various boroughs was calculated for men and women separately. The boroughs with high SMRs for men were constant. There was a pronounced change in the geographical distribution of high mortality among women. These findings support the hypothesis that the determinants of suicide differ between the sexes.

Executive Council lists and general practitioner files

An investigation of the accuracy of general practitioner and Executive Council files was approached by a comparison of the two. High error rates were found, including both file errors and record errors. On analysis it emerged that file error rates could not be satisfactorily expressed except in a time-dimensioned way, and we were unable to do this within the context of our study. Record error rates and field error rates were expressible as proportions of the number of records on both the lists; 79·2% of all records exhibited non-congruencies and particular information fields had error rates ranging from 0·8% (assignation of sex) to 68·6% (assignation of civil state). Many of the errors, both field errors and record errors, were attributable to delayed updating of mutable information.

It is concluded that the simple transfer of Executive Council lists to a computer filing system would not solve all the inaccuracies and would not in itself permit Executive Council registers to be used for any health care applications requiring high accuracy. For this it would be necessary to design and implement a purpose designed health care record system which would include, rather than depend upon, the general practitioner remuneration system.