E-health intervention for preventing recurrent ankle sprains: a randomised controlled trial in general practice

BACKGROUND

Ankle sprains are frequent injuries in general practice. However, no effective treatment is available yet.

AIM

To examine the effectiveness of an unsupervised e-health-supported neuromuscular training programme in combination with usual care compared with usual care alone in patients with acute lateral ankle sprains in general practice.

DESIGN AND SETTING

Randomised controlled trial with 1-year follow-up among patients (14-65 years) who visited the GP with an acute lateral ankle sprain within 3 weeks of injury.

METHOD

The intervention group received, in addition to usual care, an unsupervised e-health-supported neuromuscular training programme and the control group received usual care alone. The primary outcome was self-reported re-sprains during 52 weeks of follow-up. Secondary outcomes were ankle function, pain in rest and during activity, subjective recovery, and return to the same type and level of sport.

RESULTS

In total, 165 participants (mean age 38.3 years and 69 [41.8%] male) were included. No statistically significant difference in the occurrence of a re-sprain were found between the intervention 20.7% (17/82) and control group 24.1% (20/83) (hazard ratio 1.14, 95% confidence interval = 0.59 to 2.21). Also, no statistically significant differences in secondary outcomes were found between groups. The adherence rate to the programme was low (6.1%, 5/82).

CONCLUSION

The rate of re-sprains was relatively high and an unsupervised e-health-supported neuromuscular training programme does not yield meaningful effects and does not encourage adherence in preventing re-sprains in patients in general practice. More research is necessary to indicate the best treatment modality and way of delivery for these patients.

Anxiety problems in children and adolescents: a population-based cohort study on incidence and management in Dutch primary care

BACKGROUND

Due to a large strain on youth mental health care, general practice is suggested as an alternative treatment setting for children and adolescents with anxiety problems. However, research on the current management of these children and adolescents within general practice is scarce.

AIM

To investigate the incidence of coded anxiety in general practice using the International Classification of Primary Care (ICPC), and GPs' management of children and adolescents presenting with anxiety problems.

DESIGN AND SETTING

Population-based cohort study using electronic medical records of 51 212 children (aged 0-17 years) in primary care in the Rotterdam region between 1 January 2012 and 31 December 2018.

METHOD

Incidence of ICPC codes for anxiety were calculated, then the characteristics of children and adolescents consulting their GP with anxiety and the GPs' management were assessed qualitatively using quantitative content analysis.

RESULTS

Incidence of ICPC codes for anxiety in children and adolescents was 5.36 (95% confidence interval [CI] = 5.02 to 5.71) per 1000 person-years. Adolescent females had the highest incidence with 14.01 (95% CI = 12.55 to 15.58) per 1000 person-years. Of the 381 children and adolescents consulting their GP with an initial anxiety problem (median age 13.3 years, 40.4% male), GPs referred 59.3% to mental health care in the first year while 26.5% of children and adolescents were managed by a specialised practice nurse within general practice. Of the 381 children and adolescents, 10.5% received psychiatric medication during the first year, with the trend being for increased prescriptions during adolescence.

CONCLUSION

In general practice children and adolescents frequently received one of two ICPC codes for anxiety, especially adolescent females. Most presenting to their GP with anxiety problems are referred externally or seen by a specialised practice nurse within general practice.

Can we predict which patients with plantar heel pain are more likely to benefit from insoles? A secondary exploratory analysis of a randomized controlled trial

Background

Plantar heel pain (PHP) is a common cause of foot complaints, for which treatment with custom-made insoles is frequently applied. So far few studies have investigated patient characteristics that predict response to these treatments. The aim of this secondary exploratory analysis was twofold; firstly, to identify patient characteristics that predict prognosis in patients with PHP treated with insoles, and secondly to identify characteristics that might interact with treatment with insoles.

Methods

Data from a randomized trial in which participants received either custom insoles (N = 70) or sham insoles (N = 69) were used. At baseline, information was collected on demographics, foot symptoms, foot and ankle range of motion, navicular drop, presence of neuropathic pain, physical activity and other illnesses in the last 12 months. The primary outcome of this study was the Foot Function Index score (FFI) at 26 weeks. Multivariable linear regression models were generated to identify patients characteristics that predict the outcome for each type of intervention (i.e. insoles and GP-led usual care).

Results

We found two variables associated with a better function score at 26 weeks in patients treated with insoles, female sex (β − 9.59 95%CI -17.87; − 1.31) and a lower FFI score at baseline (β 0.56 95%CI 0.30; 0.82). Explorative analyses in patients treated with insoles showed no significant interaction effects between the type of insole (custom-made versus sham) and any of the potential predictive factors.

Conclusion

When communicating about the effect of insoles for PHP clinicians should take sex and the amount of pain and disability at first presentation into account. Women and people with better foot function scores at baseline (according to FFI) might respond better to treatment with insoles in terms of foot function.

Trial registration

Trial registration: NTR5346.

Does MRI add value in general practice for patients with traumatic knee complaints? A 1-year randomised controlled trial

OBJECTIVE

To determine whether referral to MRI by the general practitioner (GP) is non-inferior to usual care (no access to MRI by GPs) in patients with traumatic knee complaints regarding knee-related daily function.

METHODS

This was a multicentre, non-inferiority randomised controlled trial with 1-year follow-up. GPs invited eligible patients during or after their consultation. Eligible patients (18-45 years) consulted a GP with knee complaints due to a trauma during the previous 6 months. Patients allocated to the MRI group received an MRI at (median) 7 (IQR 1-33) days after the baseline questionnaire. Patients in the usual care group received information on the course of knee complaints, and a referral to a physiotherapist or orthopaedic surgeon when indicated. The primary outcome measure was knee-related daily function measured with the Lysholm scale (0 to 100; 100=excellent function) over 1 year, with a non-inferiority margin of 6 points.

RESULTS

A total of 356 patients were included and randomised to MRI (n=179) or usual care (n=177) from November 2012 to December 2015. MRI was non-inferior to usual care concerning knee-related daily function during 1-year follow-up, for the intention-to-treat (overall adjusted estimate: 0.33; 95% CI -1.73 to 2.39) and per-protocol (overall adjusted estimate: 0.06; 95% CI -2.08 to 2.19) analysis. There were no differences between both groups in the amount of patients visiting other healthcare providers.

CONCLUSION

MRI in general practice in patients with traumatic knee complaints was non-inferior to usual care regarding knee-related daily function during 1-year follow-up.

TRIAL REGISTRATION NUMBER

NTR3689.

Assessing the cost-effectiveness of a routine versus an extensive laboratory work-up in the diagnosis of anaemia in Dutch general practice

Background Establishing the underlying cause of anaemia in general practice is a diagnostic challenge. Currently, general practitioners individually determine which laboratory tests to request (routine work-up) in order to diagnose the underlying cause. However, an extensive work-up (consisting of 14 tests) increases the proportion of patients correctly diagnosed. This study investigates the cost-effectiveness of this extensive work-up. Methods A decision-analytic model was developed, incorporating all societal costs from the moment a patient presents to a general practitioner with symptoms suggestive of anaemia (aged ≥ 50 years), until the patient was (correctly) diagnosed and treated in primary care, or referred to (and diagnosed in) secondary care. Model inputs were derived from an online survey among general practitioners, expert estimates and published data. The primary outcome measure was expressed as incremental cost per additional patient diagnosed with the correct underlying cause of anaemia in either work-up. Results The probability of general practitioners diagnosing the correct underlying cause increased from 49.6% (95% CI: 44.8% to 54.5%) in the routine work-up to 56.0% (95% CI: 51.2% to 60.8%) in the extensive work-up (i.e. +6.4% [95% CI: -0.6% to 13.1%]). Costs are expected to increase slightly from €842/patient (95% CI: €704 to €994) to €845/patient (95% CI: €711 to €994), i.e. +€3/patient (95% CI: €-35 to €40) in the extensive work-up, indicating incremental costs of €43 per additional patient correctly diagnosed. Conclusions The extensive laboratory work-up is more effective for diagnosing the underlying cause of anaemia by general practitioners, at a minimal increase in costs. As accompanying benefits in terms of quality of life and reduced productivity losses could not be captured in this analysis, the extensive work-up is likely cost-effective.

Preventing running-related injuries using evidence-based online advice: the design of a randomised-controlled trial

Introduction

Running-related injuries (RRIs) are frequent and can lead to cessation of health promoting activities. Several risk factors for RRIs have been identified. However, no successful injury prevention programme has been developed so far. Therefore, the aim of the present study is to investigate the effect of an evidence-based online injury prevention programme on the number of RRIs.

Methods and analysis

The INSPIRE trial is a randomised-controlled trial with a 3-month follow-up. Both novice and more experienced runners, aged 18 years and older, who register for a running event (distances 5 km up to 42.195 km) will be asked to participate in this study. After completing the baseline questionnaire, participants will be randomised into either the intervention group or control group. Participants in the intervention group will get access to the online injury prevention programme. This prevention programme consists of information on evidence-based risk factors and advices to reduce the injury risk. The primary outcome measure is the number of self-reported RRIs in the time frame between registration for a running event and 1 month after the running event. Secondary outcome measures include the running days missed due to injuries, absence of work or school due to injuries, and the injury location.

Ethics and dissemination

An exemption for a comprehensive application is obtained by the Medical Ethical Committee of the Erasmus University Medical Centre Rotterdam, Netherlands. The results of the study will be published in peer-reviewed journals and presented on international congresses.

Trial registration number

NTR5998. Pre-results

The STAP-study: The (cost) effectiveness of custom made orthotic insoles in the treatment for plantar fasciopathy in general practice and sports medicine: design of a randomized controlled trial

BACKGROUND

Plantar fasciopathy is a common cause of foot pain, accounting for 11 to 15% of all foot symptoms requiring professional care in adults. Although many patients have complete resolution of symptoms within 12 months, many patients wish to reduce this period as much as possible. Orthotic devices are a frequently applied option of treatment in daily practice, despite a lack of evidence on the effectiveness. Therefore, the objective is to study the (cost)-effectiveness of custom made insoles by a podiatrist, compared to placebo insoles and usual care in patients with plantar fasciopathy in general practice and sports medicine clinics.

METHOD/DESIGN

This study is a multi-center three-armed participant and assessor-blinded randomized controlled trial with 6-months follow-up. Patients with plantar fasciopathy, with a minimum duration of complaints of 2 weeks and aged between 18 and 65, who visit their general practitioner or sport physician are eligible for inclusion. A total of 185 patients will be randomized into three parallel groups. One group will receive usual care by the general practitioner or sports physician alone, one group will be referred to a podiatrist and will receive a custom made insole, and one group will be referred to a podiatrist and will receive a placebo insole. The primary outcome will be the change from baseline to 12 weeks follow-up in pain severity at rest and during activity on a 0-10 numerical rating scale (NRS). Secondary outcomes include foot function (according to the Foot Function Index) at 6, 12 and 26 weeks, recovery (7-point Likert) at 6, 12 and 26 weeks, pain at rest and during activity (NRS) at 6 and 26 weeks and cost-effectiveness of the intervention at 26-weeks. Measurements will take place at baseline and at, 2, 4, 6, 12 and 26 weeks of follow-up.

DISCUSSION

The treatment of plantar fasciopathy is a challenge for health care professionals. Orthotic devices are frequently applied, despite a lack of evidence of the effectiveness on patient reported outcome. The results of this randomized controlled trial will improve the evidence base for treating this troublesome condition in daily practice.

TRIAL REGISTRATION

Dutch Trial Registration: NTR5346 . Date of registration: August 5(th) 2015.

Ischaemic cardiovascular risk and prescription of non-steroidal anti-inflammatory drugs for musculoskeletal complaints

OBJECTIVE

To determine the influence of ischaemic cardiovascular (CV) risk on prescription of non-steroidal anti-inflammatory drugs (NSAIDs) by general practitioners (GPs) in patients with musculoskeletal complaints.

DESIGN

Cohort study.

SETTING

A healthcare database containing the electronic GP medical records of over one million patients throughout the Netherlands.

PATIENTS

A total of 474 201 adults consulting their GP with a new musculoskeletal complaint between 2000 and 2010. Patients were considered at high CV risk if they had a history of myocardial infarction, angina pectoris, stroke, transient ischaemic attack, or peripheral arterial disease, and at low CV risk if they had no CV risk factors.

MAIN OUTCOME MEASURES

Frequency of prescription of non-selective (ns)NSAIDs and selective cyclooxygenase-2 inhibitors (coxibs).

RESULTS

Overall, 24.4% of patients were prescribed an nsNSAID and 1.4% a coxib. Of the 41,483 patients with a high CV risk, 19.9% received an nsNSAID and 2.2% a coxib. These patients were more likely to be prescribed a coxib than patients with a low CV risk (OR 1.9, 95% CI 1.8-2.0). Prescription of nsNSAIDs decreased over time in all risk groups and was lower in patients with a high CV risk than in patients with a low CV risk (OR 0.8, 95% CI 0.7-0.8).

CONCLUSION

Overall, patients with a high CV risk were less likely to be prescribed an NSAID for musculoskeletal complaints than patients with a low CV risk. Nevertheless, one in five high CV risk patients received an NSAID, indicating that there is still room for improvement.

The effect of two lottery-style incentives on response rates to postal questionnaires in a prospective cohort study in preschool children at high risk of asthma: a randomized trial

Background

In research with long-term follow-up and repeated measurements, quick and complete response to questionnaires helps ensure a study’s validity, precision and efficiency. Evidence on the effect of non-monetary incentives on response rates in observational longitudinal research is scarce.

Objectives

To study the impact of two strategies to enhance completeness and efficiency in observational cohort studies with follow-up durations of around 2 years.

Method and intervention

In a factorial design, 771 children between 2 and 5 years old and their parents participating in a prospective cohort study were randomized to three intervention groups and a control group. Three types of lotteries were run: (i) daytrip tickets for the whole family to a popular amusement park if they returned all postal questionnaires, (ii) €12.50-worth gift vouchers for sending back the questionnaire on time after each questionnaire round and (iii) a combination of (i) and (ii).

Main outcome measures

Primary outcome was the proportion of participants who returned all questionnaires without any reminder. Secondary outcomes were ‘100% returned with or without reminder’, ‘probability of 100% non-response’, ‘probability of withdrawal’, ‘proportion of returned questionnaires’ and ‘overall number of reminders sent’.

Statistical analysis

After testing for interaction between the two lottery interventions, the two trials were analysed separately. We calculated risk differences (RD) and numbers needed to “treat” and their 95% confidence intervals.

Results

Daytrip nor voucher intervention had an effect on the proportion of participants who returned all questionnaires (RD −0.01; 95% CI-0.07 – 0.06) and (RD 0.02; 95% CI-0.50 – 0.08), respectively. No effects were found on the secondary outcomes.

Conclusion

Our findings do not support the idea that lottery-style incentives lead to more complete response to postal questionnaires in observational cohort studies with repeated data collection and follow-up durations of around 2 years.

ENT problems in Dutch children: trends in incidence rates, antibiotic prescribing and referrals 2002-2008

BACKGROUND. Ear, nose, and throat (ENT) problems are common in childhood and are important reasons to visit the general practitioner. OBJECTIVE. To examine trends in incidence rates, antibiotic prescribing, and referrals of five common ENT problems in children. DESIGN. Netherlands Information Network of General Practice (LINH), a nationally representative general practice database. Setting. A total of 50 000 children, aged 0-17 years, registered in Dutch general practice over the period 2002-2008. METHODS. Incidence rates were calculated and trends were analysed using linear regression analysis, with incidence rates per age group, proportion treated with antibiotics, and referrals as dependent variables and year of observation as independent variable. RESULTS. In general, incidence rates of acute otitis media, serous otitis, sinusitis, tonsillitis, and tonsil hypertrophy remained stable over the period 2002-2008. An increasing trend was observed for serous otitis media in children aged 0-4 years (RR = 1.04, p < 0.001). A decreasing trend was observed for sinusitis in children aged 5-11 and for tonsillitis in children aged 11-17 years (RR 0.99, p < 0.001 and RR 0.94, p < 0.001, respectively). Antibiotics were prescribed in 10-60% of the diagnoses. An increasing trend for antibiotic prescription was found for acute otitis media (beta = 0.07, p < 0.001), mainly on account of amoxicillin. Although antibiotic treatment of tonsillitis remained stable, pheneticillin prescriptions showed a downward trend (beta = -0.10, p < 0.001). First-choice antibiotics were prescribed in >80% of cases. CONCLUSIONS. This study showed remarkably stable trends in incidence rates, antibiotic prescribing, and referrals of common ENT problems. The low proportion of antibiotic treatment in ENT problems did not show negative consequences.

Low hospital admission rates for respiratory diseases in children

Background

Population-based data on hospital admissions for children aged 0-17 years concerning all respiratory diseases are scarce. This study examined hospital admissions in relation to the preceding consultations in general practice in this age group.

Methods

Data on children aged 0-17 years with respiratory diseases included in the Second Dutch National Survey of General Practice (DNSGP-2) were linked to all hospital admissions in the Dutch National Medical Registration. Admission rates for respiratory diseases were calculated. Data were analysed using multivariate logistic regression.

Results

Of all 79,272 children within the DNSGP-2, 1.8% were admitted to hospital for any respiratory diagnosis. The highest admission rates per 1000 children were for chronic disease of tonsils and adenoids (12.9); pneumonia and influenza (0.97); and asthma (0.92). Children aged 0-4 years and boys were admitted more frequently. Of children with asthma, 2.3% were admitted for respiratory diseases. For asthma, admission rates varied by urbanisation level: 0.47/1000 children/year in cities with ≤ 30,000 inhabitants, 1.12 for cities with ≥ 50,000 inhabitants, and 1.73 for the three largest cities (p = 0.002). Multivariate logistic regression showed that within two weeks after a GP consultation, younger age (OR 0.81, 95% CI 0.76-0.88) and more severe respiratory diseases (5.55, 95% CI 2.99-8.11) predicted hospital admission.

Conclusions

Children in the general population with respiratory diseases (especially asthma) had very low hospital admission rates. In urban regions children were more frequently admitted due to respiratory morbidity. For effectiveness studies in a primary care setting, hospital admission rates should not be used as quality end-point.

A cost minimisation analysis in teledermatology: model-based approach

Background

Although store-and-forward teledermatology is increasingly becoming popular, evidence on its effects on efficiency and costs is lacking. The aim of this study, performed in addition to a clustered randomised trial, was to investigate to what extent and under which conditions store-and-forward teledermatology can reduce costs from a societal perspective.

Methods

A cost minimisation study design (a model based approach) was applied to compare teledermatology and conventional process costs per dermatology patient care episode. Regarding the societal perspective, total mean costs of investment, general practitioner, dermatologists, out-of-pocket expenses and employer costs were calculated. Uncertainty analysis was performed using Monte Carlo simulation with 31 distributions in the used cost model. Scenario analysis was performed using one-way and two-way sensitivity analyses with the following variables: the patient travel distance to physician and dermatologist, the duration of teleconsultation activities, and the proportion of preventable consultations.

Results

Total mean costs of teledermatology process were €387 (95%CI, 281 to 502.5), while the total mean costs of conventional process costs were €354.0 (95%CI, 228.0 to 484.0). The total mean difference between the processes was €32.5 (95%CI, -29.0 to 74.7). Savings by teledermatology can be achieved if the distance to a dermatologist is larger (> = 75 km) or when more consultations (> = 37%) can be prevented due to teledermatology.

Conclusions

Teledermatology, when applied to all dermatology referrals, has a probability of 0.11 of being cost saving to society.

In order to achieve cost savings by teledermatology, teledermatology should be applied in only those cases with a reasonable probability that a live consultation can be prevented.

Trail Registration

This study is performed partially based on PERFECT D Trial (Current Controlled Trials No.ISRCTN57478950).

Pilot study evaluating the effects of an intervention to enhance culturally appropriate hypertension education among healthcare providers in a primary care setting

Background

To improve hypertension care for ethnic minority patients of African descent in the Netherlands, we developed a provider intervention to facilitate the delivery of culturally appropriate hypertension education. This pilot study evaluates how the intervention affected the attitudes and perceived competence of hypertension care providers with regard to culturally appropriate care.

Methods

Pre- and post-intervention questionnaires were used to measure the attitudes, experienced barriers, and self-reported behaviour of healthcare providers with regard to culturally appropriate cardiovascular and general care at three intervention sites (N = 47) and three control sites (N = 35).

Results

Forty-nine participants (60%) completed questionnaires at baseline (T0) and nine months later (T1). At T1, healthcare providers who received the intervention found it more important to consider the patient's culture when delivering care than healthcare providers who did not receive the intervention (p = 0.030). The intervention did not influence experienced barriers and self-reported behaviour with regard to culturally appropriate care delivery.

Conclusion

There is preliminary evidence that the intervention can increase the acceptance of a culturally appropriate approach to hypertension care among hypertension educators in routine primary care.

Exploring the black box of change in improving test-ordering routines

BACKGROUND

The effects of quality improvement strategies are sometimes limited in spite of a systematic development approach. What elements play a role in the change process is not yet fully understood.

OBJECTIVE

To explore this 'black box' of change, by analysing the barriers and facilitators GPs perceive during the change process.

METHODS

Qualitative study among GPs who participated in the quality improvement strategy arm of a randomized clinical trial on blood test ordering for unexplained complaints (UCs). The strategy was based on a national guideline that advocates delayed test ordering in patients presenting with UCs. Each GP's change process was assessed by means of a semi-structured interview about barriers to and facilitators of change.

RESULTS

Twenty-four interviews were analysed. Important themes identified in the interviews were lack of problem awareness, the time and effort it takes to change, influence of patients and the pros and cons of the changed behaviour.

CONCLUSION

The themes can be summarized into one comprehensive issue: the GPs lack a sense of urgency to change. An important explanation seems to be that two questions from the problem analysis prior to the development of the strategy had not been adequately answered: "Is the GPs' current behaviour a problem and does the problem have consequences for patients?" and if so, "What is the extent of the problem?." As a result, insufficient attention was given to applicability issues, such as time investment, costs and patient and practitioner satisfaction and anxiety.

Recently enlisted patients in general practice use more health care resources

Background

The continuity of care is one of the cornerstones of general practice. General practitioners find personal relationships with their patients important as they enable them to provide a higher quality of care. A long-lasting relationship with patients is assumed to be a prior condition for attaining this high quality. We studied the differences in use of care between recently enlisted patients and those patients who have been enlisted for a longer period.

Methods

104 general practices in the Netherlands participated the study. We performed a retrospective cohort study in which patients who have been enlisted for less than 1 year (n = 10,102) were matched for age, sex and health insurance with patients who have been enlisted for longer in the same general practice. The two cohorts were compared with regard to the number of contacts with the general practice, diagnoses, rate of prescribing, and the referral rate in a year. These variables were chosen as indicators of differences in the use of care.

Results

In the year following their enlistment, a higher percentage of recently enlisted patients had at least one contact with the practice, received a prescription or was referred. They also had a higher probability of receiving a prescription for an antibiotic. Furthermore, they had a higher mean number of contacts and referrals, but not a higher mean number of prescriptions.

Conclusion

Recently enlisted patients used more health care resources in the first year after their enlistment compared to patients enlisted longer. This could not be explained by differences in health.

Antibiotics and steroids for exacerbations of COPD in primary care: compliance with Dutch guidelines

BACKGROUND

The Dutch College of General Practitioners' guidelines specify that antibiotics should only be used for severe cases of chronic obstructive pulmonary disease (COPD). However, GPs tend to administer antibiotics rather than a short course of steroid treatment regardless of severity.

AIM

The aim of this study was to determine how GPs use current guidelines in treating exacerbations of COPD, in particular whether short courses of oral steroids and antibiotics are prescribed in accordance with the Dutch guidelines for COPD.

DESIGN OF STUDY

Retrospective analysis of medical records.

SETTING

Primary healthcare centres.

METHOD

Medical records of patients registered at four primary healthcare centres in the Netherlands were retrospectively analysed for the period March 2001-March 2003.

RESULTS

Of 35,589 patients, 1.3% were registered as having a diagnosis of COPD. In 2 years, 47% of the patients had no exacerbation, 35% had one or two exacerbations, and 18% had three or more exacerbations. Of 536 exacerbations, GPs prescribed a short course of oral steroids in 30% of cases, antibiotics in 29%, steroids combined with an antibiotic in 23%, and no oral steroid course or antibiotic was prescribed in 18%. Prescriptions for patients with three or more exacerbations differed significantly from those for patients with one or two exacerbations.

CONCLUSIONS

Treatment is often not in accordance with current guidelines; in particular, antibiotics are prescribed more often than recommended.

Added value of co-morbidity in predicting health-related quality of life in COPD patients

The extent to which a chronic obstructive pulmonary disease (COPD) patient is impaired in health-related quality of life (HRQoL) is only to a small extent reflected in clinical and demographical measures. As the influence of comorbidity on HRQoL is less clear, we investigated the added value of 23 common diseases in predicting HRQoL in COPD patients with mild to severe airways obstruction. COPD patients from general practice who appeared to have an forced expiratory volume in 1 sec/inspiratory vital capacity (FEV1/IVC) < predicted -1.64 SD, FEV1 <80% predicted, FEV1 reversibility < 12% and a smoking history, were included (n=163). HRQoL was assessed with the short-form-36 (SF-36) and the presence of comorbidity was determined by a questionnaire, which asked for 23 common diseases. All domains of the SF-36 were best predicted by the presence of three or more co-morbid diseases. FEV1 % predicted, dyspnoea and the presence of one or two diseases were second-best predictors. Co-morbidity explained an additional part of the variance in HRQoL, particularly for emotional functioning (delta R2=0.11). When individual diseases were investigated, only insomnia appeared to be related to HRQoL. As HRQoL is still only partly explained, co-morbidity and other patient characteristics do not clearly distinguish between COPD patients with severe impairments in HRQoL and COPD patients with minor or no impairments in HRQoL. Therefore, it remains important to ask for problems in daily functioning and well-being, rather than to rely on patient characteristics alone.

Prevalence of comorbidity in patients with a chronic airway obstruction and controls over the age of 40

The goal of this study is to determine the prevalence of 23 common diseases in subjects with a chronic airway obstruction and in controls. All subjects with a known diagnosis by their general practitioner of asthma or chronic obstructive pulmonary disease (COPD), and who were 40 years and older were selected (n = 1145). Subjects who were willing to participate (n = 591) and who appeared to have an irreversible airway obstruction (n = 290) were included. To recruit controls, a random sample was taken of 676 individuals who were 40 years and older and who were not diagnosed as having asthma or COPD by their general practitioner. Of these 676 individuals 421 were willing to participate. The presence of diseases was determined by using a questionnaire. One hundred and ninety-four subjects (73%) and 229 controls (63%) were shown to be suffering from one or more (other) diseases. In both groups, locomotive diseases, high blood pressure, insomnia and heart disease were most common. Locomotive diseases, insomnia, sinusitis, migraine, depression, stomach or duodenal ulcers and cancer were significantly more common in the subject group than in the control group. For both clinical and research purposes, it is important to consider the presence of diseases in patients with a chronic airway obstruction.

Relation between IgG antibodies to foods and IgE antibodies to milk, egg, cat, dog and/or mite in a cross-sectional study

BACKGROUND

Because IgG antibodies to foods can be detected before IgE antibodies to inhalants, increased levels of IgG antibodies to foods might be used as a predictor of IgE-mediated allergy in initially nonatopic children.

OBJECTIVE

To examine the cross-sectional relation between IgG to foods (i.e. mixture of wheat and rice, mixture of soybean and peanut, egg white, cow's milk, meat, orange and potato) and specific IgE to cat, dog, mite, milk and egg white in 1-year-old children.

METHODS

All atopic children (n = 120; 58 with and 62 without eczema) and a random sample of the nonatopic children (n = 144) of the Bokaal study were tested on their IgG response to foods. The IgG results of the food assays were dichotomized high or low using the 66th centile as a cut-off value.

RESULTS

Atopic children more often had high IgG levels to foods than nonatopic children. IgG to egg white (OR = 7.50) and mixture of wheat and rice (OR = 4.79) were most strongly associated with positive specific IgE. In a stepwise logistic regression analysis egg white, mixture of wheat and rice, and orange were selected (OR = 3.76, OR = 2.43, and OR = 2.11, respectively). In children without eczema higher levels of IgG to foods were still significantly associated with atopy, which was most prominent for egg white, orange and cow's milk.

CONCLUSION

An increased IgG antibody level to foods, especially to egg white, orange, and mixture of wheat and rice, indicates an increased risk of having IgE to cat, dog, mite, egg and/or milk allergens, even in the noneczematous group. Therefore, in another prospective study we are currently investigating the usefulness of IgG in early identification, i.e. before IgE antibodies can be detected, of children with an increased risk of developing allergic diseases in the future.

Changing attitudes towards antiretroviral treatment of HIV infection: a prospective study in a sample of Dutch general practitioners

This study investigated the attitude towards antiretroviral therapy (ART) for HIV infection over time, in a sample of Dutch general practitioners (GPs). Twenty-one GPs, of which 16 were practising in Amsterdam, completed multiple questionnaires on HIV-related topics between April 1995 and March 1997. In 1995, only 10% had a positive attitude towards treatment of asymptomatic persons with a CD4+ > 300 x 10(6)/l; at the end of the study 43% had. In 1995, 57% had a positive attitude towards treatment of asymptomatic persons with a CD4+ < or = 300 x 10(6)/l, and 52% towards treatment of symptomatic patients with a CD4+ < or = 400 x 10(6)/l; heterosexual GPs more often had a positive attitude as compared to homosexual GPs (p = 0.005 and p = 0.01, respectively). At the end of the study the proportions of GPs with a positive attitude had increased from 57 to 81% and 52 to 95%, respectively. The risk of adverse effects, strict dose regimens and medicalization were regarded as the main disadvantages of the current treatment strategy. The conclusion is that the attitude towards ART has become more positive since 1995. At the beginning of 1997, however, there still existed reservations about treatment of asymptomatic persons with CD4+ cell counts > 300 x 10(6)/l.

[Chronic use of stomach acid inhibitor medication in family practice in the region of Amsterdam]

OBJECTIVE

To investigate the magnitude of long-term prescription of acid secretion suppressant therapy in general practice, the frequency and methods of objectivation of the primary working diagnosis and the clinical grounds for the first prescription.

DESIGN

Retrospective.

METHOD

Patients on long-term acid suppressant therapy were identified in a population of 46,813 patients in 24 general practices in the Amsterdam region by extraction from computerized medication databases of the pharmacists. The indications for the prescription and the investigations performed to confirm the working diagnosis were extracted from the patients' files in the GP practices. Long-term acid suppressant therapy was defined as prescription for at least 12 weeks in the period September 1994-August 1995.

RESULTS

922/46,813 patients (2%) were on long-term acid suppressant therapy. Mean duration of prescription was 33 weeks. The duration of prescription varied from 12 weeks in 8% of the patients to > 52 weeks in 23%. In 25% of the patients no objectivating investigations were performed, in 75% endoscopy or radiology was done; the predominant diagnoses were ulcerative disease (39%) and/or gastroesophageal reflux disease (49%) and functional dyspepsia (gastritis, or normal aspect) (18%). The Helicobacter pylori status had been established in 29% of the patients with ulcerative disease. Eradication therapy was reported in 44% of these patients.

CONCLUSION

Long-term acid suppressant therapy is frequently administered without a confirmed working diagnosis. An important part of the patients need H. pylori diagnostics, H. pylori eradication therapy and if possible tapering off of their medication.

Evaluation of an expanded two-ELISA approach for confirmation of reactive serum samples in an HIV-screening programme for pregnant women

Serum specimens were collected from 31,232 pregnant women in Amsterdam between 1988 and 1995 in a screening programme for human deficiency virus (HIV) infection. The sera of 56 (0.179%) women tested were confirmed as positive for HIV. A total of 67 sera reacted positive or borderline by the screening enzyme-linked immunosorbent assay (ELISA) and indeterminate or negative by HIV-1 Western blot; 42 of these specimens were available for evaluation of the strategy for diagnosis of HIV infection. A two-ELISA approach with the second ELISA based on a principle different from that of the screening ELISA, expanded with the use of a membrane immunoassay based on two synthetic peptides specific for HIV-1 gp41 and HIV-2 gp36 envelope proteins, was compared with the Western blot analysis. Indeterminate results were resolved with a nucleic acid sequence-based amplification assay (NASBA) for HIV-1 RNA and a strip immunoassay (SIA) for the simultaneous detection of antibodies to HIV-1 or HIV-2 and HIV-1 p24 antigen. Eleven samples were weakly or borderline positive by the screening test and gave indeterminate results by Western blot. The expanded two-ELISA approach designated these sera as HIV-negative, and confirmed negative by NASBA and the SIA. Twenty-one samples showed borderline or positive results on the screening test and negative results by Western blot. Again, these sera were characterised as HIV-negative by the expanded two-ELISA procedure, and this characterisation was confirmed by both NASBA and the SIA. Five HIV-2-positive serum samples were recognised by the expanded two-ELISA approach and the SIA; these sera were negative by NASBA. Finally, another five serum samples were weakly or borderline positive by both ELISAs and positive by the membrane immunoassay; of these five, two sera generated positive patterns and the other three indeterminate patterns on Western blots, and four were positive by the NASBA assay. Follow-up serum specimens from these five women were negative and the reactivity of the initial specimens was thus likely to have been the result of cross-contamination. Our results demonstrate the effectiveness of a simple confirmation approach of two HIV ELISAs expanded with a membrane spot assay to discriminate between infection with HIV-1 or HIV-2. The data also indicate the importance of retesting individuals with indeterminate or positive confirmational results to exclude the possibility of contamination as the cause of reactivity of the original specimen.

[AIDS epidemic in The Netherlands: current developments in transmission route, age and nationality]

OBJECTIVE

To document the recent developments in the course of the AIDS epidemic in the Netherlands, 1982-1995.

DESIGN

Descriptive.

SETTING

National Institute of Public Health and Environment, Bilthoven, Municipal Health Service, Amsterdam, and Inspectorate of Public Health, Rijswijk, the Netherlands.

METHOD

Based on the new AIDS patients reported to the Inspectorate of Public Health, the incidence figures were calculated by risk group (homo/bisexual men, intravenous drug users and heterosexual men and women), by birth cohort defined by 5 successive years of birth, and by nationality, in order to characterise sub-epidemics.

RESULTS

Among homo/bisexual men AIDS incidence has been stabilizing in recent years. Among intravenous drug users and heterosexuals incidence continues to rise but at a low level compared with homo/bisexual men. Among homo/bisexual men and intravenous drug users mean age at AIDS diagnosis is rising in conjunction with reduced incidence among young persons born in 1965-1969 when compared with the incidence among persons born in 1960-1964 when at the same age. By contrast, among heterosexuals a decline in mean age at diagnosis is observed and this decline coincides with undiminished rise of incidence among persons born in 1965-1969. Among heterosexual patients an increasing and disproportionate number have the nationality of a sub-Saharan African country.

CONCLUSION

Future AIDS incidence among homo/bisexual men and intravenous drug users will probably be lower than it currently is. Regarding heterosexuals the undiminished growth of the number of young AIDS patients and the increasing proportion of patients from abroad make such an assessment more difficult.

Estimating the size of the HIV epidemic among injecting drug users in Amsterdam

Aim of this study was to assess the cumulative incidence of HIV-infection, AIDS and pre-AIDS death in the population of injecting drug users (IDU) in Amsterdam. By assuming equivalence, between a cohort of IDU and the IDU population, of the ratios of incidences of AIDS and pre-AIDS death to the number of HIV positive persons giving rise to these incidences, the numbers of HIV positive persons and pre-AIDS deaths in the population could be calculated, given that other parameters were known. Cohort study data on HIV prevalence and incidences of HIV infection, AIDS, and pre-AIDS death, were combined with national AIDS surveillance data. As of 1 October 1994, the estimated cumulative number of HIV positive IDU in Amsterdam was approximately 1280, far higher than a recent back-calculation estimate. Of the 1280, 204 HIV positive IDU had been diagnosed with AIDS, while about 270 had died pre-AIDS. The HIV prevalence of IDU residing in Amsterdam that were still alive and free of AIDS was hence estimated at around 800. Since the incidence of pre-AIDS death and AIDS exceeded the number of seroconversions during the past four years, the HIV epidemic among IDU in Amsterdam appears to be dwindling. A lower bound of the number of HIV positive IDU being alive, AIDS-free and living elsewhere in the Netherlands was roughly estimated at 600. Because of untimely deaths, only a limited number of HIV positive IDU can be expected to be diagnosed with AIDS in the future. Since these estimates are based upon some rather bold assumptions, they should be interpreted with caution and require further validation by independent sources.

[Results of screening for HIV antibodies in pregnant women in Amsterdam reference stations, 1988-1995]

In order to determine the prevalence of HIV in the general heterosexual population of Amsterdam, 16,709 pregnant women attending two hospitals and one maternity clinic in the period 1988-1995 were asked to undergo a HIV test, of whom 15,276 gave informed consent (91.4%). Pregnant women with a risk of HIV infection were possibly overrepresented in those who refused. The overall HIV prevalence in 1988-1995 was 0.28% and showed no significant differences over the years. In women with a known risk factor for infection the prevalence was 240:10,000, in those without 5:10,000. Whereas intravenous drug use was the most probable cause of infection before 1993, since then it was observed in only 2/20 of the HIV positive pregnant women. Heterosexual transmission appears to be increasing.

The impact of drug users on inpatient hospital care during the human immunodeficiency virus epidemic in Amsterdam

BACKGROUND

As a consequence of the human immunodeficiency virus (HIV) epidemic, which continues among illicit drug users, high rates of HIV-associated morbidity are believed to exist. This study focuses on hospitalizations of drug users and on the relative contribution of drug users to the total burden of inpatient hospital care in Amsterdam.

METHODS

During the years 1990-1992, data were collected on hospital admissions of injecting and non-injecting drug users to all 10 general and university hospitals in the city of Amsterdam (population 700 000; estimated number of drug users 5800). Total number of admissions, total days of hospitalization and primary discharge diagnoses according to HIV serostatus and sex were determined for drug users.

RESULTS

A total of 1293 admissions were recorded among 842 hospitalized drug users. Between 53% and 77% of days of hospitalization attributable to drug users related to HIV-infected patients, and at least 23% to patients with AIDS. In the 20-44 age group of the Amsterdam population, 5.1% of days of hospitalization for men and 1.8% for women could be attributed to drug users, or about twice as much as could be expected from their numbers alone. For all ages, the contribution of drug users to hospitalizations was 1.2% for males, 0.4% for females, and 0.8% for all. Drug users occupied an average of 19 hospital beds, corresponding to an annual cost of US$ 3.1 million. Due to underreporting of admissions, these figures should be considered lower bound estimates.

CONCLUSIONS

On the total scale of inpatient hospital expenditure in Amsterdam, the contribution of illicit drug users appears to be small.

Euthanasia and physician-assisted suicide in homosexual men with AIDS

BACKGROUND

In the Netherlands a nationwide study has shown that, in 38% of deaths, there have been medical decisions concerning the end of life (MDEL); 2.1% of all deaths were brought about by euthanasia or physician- assisted suicide (PAS). We investigated the incidence of MDEL in homosexual men with AIDS, suspecting that it might be higher, and studied the effect of euthanasia/PAS on survival time.

METHODS

The patients were 131 male homosexual participants in a cohort study in Amsterdam, diagnosed between 1985 and 1992 as having AIDS; all had died before Jan 1, 1995. Clinical and laboratory data and information on mode of death were obtained from their physicians and by review of hospital records. Those who died by euthanasia/PAS or in whom there had been other MDEL were then compared with those who died naturally.

FINDINGS

29 men (22%) had died by euthanasia/PAS and in 17 (13%) another MDEL had been made; thus, more than one-third of these men had made medical decisions concerning the end of life. The greatest difference between the groups was in age at time of diagnosis-72% aged 40 or more in the euthanasia/PAS group compared with 38% in the natural death group. The likelihood (relative risk) of euthanasia/PAS increased with duration of survival after AIDS diagnosis. Comparison of the groups in terms of three laboratory markers (CD4+ and CD8+ cells and phytohaemagglutinin responses) in the two years before death, and estimates of these markers at the time of death, did not indicate any substantial shortening of life by euthanasia/PAS; in the judgment of the physicians, most of these patients would have died naturally within one month.

INTERPRETATION

A possible reason for the high incidence of MDEL in this cohort was a good knowledge of the characteristics of AIDS acquired through long-term awareness of HIV infection. The higher rate of euthanasia in those with long survival from AIDS diagnosis could reflect either additional suffering or the greater opportunity to discuss this option with friends and physicians. Our findings indicate that euthanasia and other MDEL did little to shorten life; rather, they were an extreme form of palliation, applied in the terminal phase of a lethal disease.

The predictive value of T cell function in vitro and pre-AIDS zidovudine use for survival after AIDS diagnosis in a cohort of homosexual men in Amsterdam

The best independent predictors of survival after AIDS diagnosis were determined in 160 homosexual men from the Amsterdam Cohort Study (1987 CDC case definition). In a Cox model, all pre-AIDS laboratory markers gathered during follow-up in the study did not independently predict survival after AIDS. A second analysis, using data available only at AIDS diagnosis, revealed that T cell reactivity after stimulation with phytohemagglutinin and monoclonal CD3 antibodies and the CD4+ cell count at diagnosis were independent predictors of survival. In an interval-based Cox model, the predictive value of pre-AIDS zidovudine use was determined. One year after AIDS diagnosis, participants with pre-AIDS zidovudine use had a worse survival probability (relative hazard = 3.99). In conclusion, the survival probability of homosexual men with AIDS can be estimate adequately using information obtained at clinical AIDS diagnosis. Analysis revealed the important predictive value of T cell function tests in vitro.

[Prevalence of HIV antibodies in pregnant women in the Amsterdam HIV reference station research, 1988-1993]

Pregnant women were asked to undergo a HIV test in two hospitals, one maternity clinic (n = 12.784; 1988-1993) and one abortion clinic (n = 2089; 1990-1993) in Amsterdam, in order to establish trends in HIV prevalence. Participation rates were 92.4% and 84.4%, respectively. Among pregnant women the overall HIV prevalence was 0.27% (0.04% for pregnant women without a known HIV risk and 2.6% for women with a known HIV risk) and in the abortion clinic the overall HIV prevalence was 0.91%. The HIV prevalence over the years remained fairly constant. In the most recent years a slight rise was noticed in the HIV prevalence in the group pregnant women with a known HIV risk caused by an increase in the number of women from AIDS endemic countries in this group.

Determinants of penicillinase producing Neisseria gonorrhoeae infections in heterosexuals in Amsterdam

BACKGROUND AND OBJECTIVES

At the STD clinic of the Municipal Health Service in Amsterdam, the annual number of infections with penicillinase-producing Neisseria gonorrhoeae (PPNG) strains remained relatively stable from 1983 until 1990, while the number of non-PPNG infections declined dramatically. To investigate the PPNG and non-PPNG epidemic, a cross sectional study was conducted in 1989 and 1990. The purpose of this study was to assess determinants of PPNG infections among heterosexuals diagnosed with gonorrhoeae.

METHODS

In addition to routinely collected data in new consultations for STDs, information on alcohol use, drug use and sexual behaviour was obtained from patients diagnosed with gonorrhoea. The diagnosis of gonorrhoea was based on a positive culture and isolates were screened for PPNG. Logistic regression analysis was used to assess independent predictors of PPNG infection.

RESULTS

Additional information was available of 328 women and 995 heterosexual men diagnosed with gonorrhoea. PPNG was diagnosed in 86/328 (26%) women and in 329/995 (33%) men. Logistic regression analysis identified a Central/South American nationality (odds ratio(OR) = 2.46) and older age (OR = 1.04 per year) as positively associated with PPNG infection in female patients. An inverse relation was found with use of hard drugs (OR = 0.29). Among men diagnosed with gonorrhoea, sexual contacts with window prostitutes (mainly women from Central/South America) (OR = 1.98) and a foreign nationality (OR = 1.78) were positively associated with PPNG infection, and sexual contact with drug using prostitutes (OR = 0.47) inversely.

CONCLUSIONS

PPNG infections were especially common among Central and South American window prostitutes and their clients, but not among hard-drug addicted prostitutes and their clients. Since window prostitutes originating from Central and South American countries are transient in Amsterdam, prevention activities targeted at these prostitutes and their clients should be continued to limit the spread of PPNG and other STDs within these groups.

The HIV prevalence among pregnant women in the Amsterdam region (1988-1991)

The objective of the study was to monitor the HIV prevalence in the years 1988-1991 among pregnant women in the Amsterdam region, visitors to an abortion clinic and 3 outpatient infertility clinics. All women attending these clinics were asked to participate in the study on a voluntary basis and were tested with informed consent. The women were questioned about risk-bearing behaviour of themselves and their sexual partner(s). In the period 1988-1991, of the 23,827 eligible pregnant women, 22,165 women participated (93.0%). Twenty-seven women were found to be positive for HIV antibodies (0.12%, 95% CI: 0.08%-0.17%), of whom twenty belonged to a known HIV risk group or had a partner who belonged to one of these groups and 7 women had no known HIV risk. Seventeen of the 27 women had a foreign nationality. The annual HIV prevalence among pregnant women was: 1988: 0.28%; 1989: 0.10%; 1990: 0.10%; 1991: 0.11%. In the years 1990 and 1991, of the 1,128 eligible women visiting the abortion clinic 953 (84.5%) were tested. Eleven women were HIV-seropositive (1.15%, 95% CI: 0.6%-2.0%), of whom 9 were from an AIDS endemic region, 1 woman had a partner from this region and 1 woman had no known HIV risk. Four African women had HIV-2 antibodies. At the 3 outpatient infertility clinics 1 woman was found to be HIV-positive (0.13%; 95% CI: 0.02-0.9). She had no other risk than a partner from an AIDS endemic area. In the Amsterdam region there was a steady and low HIV prevalence (0.1%) among pregnant women through the years 1988-1991. The prevalence in the abortion clinic was ten times higher. The program was able to detect possible high risk groups within the population. Migration and travelling can play an important role in the spread of HIV in the general heterosexual population.

[Survival of patients following the diagnosis of AIDS in the Amsterdam region, 1982-1991]

OBJECTIVE

To evaluate the survival of 975 AIDS patients diagnosed in the Amsterdam region between 1982 and 1991, with follow-up until December 31st, 1992.

METHODS

Analysis of data from the active AIDS surveillance system for the Amsterdam region at the Municipal Health Service.

RESULTS

Amsterdam region residents had 1, 2 and 3-year survivals of 69.8%, 42.6% and 21.2%, respectively. The 5-year survival was 7.7%. The median survival probability for all patients showed great improvement, from 9 months in 1982-1985 to 26 months in 1990. For patients initially presenting with only Pneumocystis carinii pneumonia (PCP) the greatest improvement occurred between the period 1982-1985 and the year 1986. For patients without PCP the most important improvement occurred one year later. From 1988 onwards no important improvement in the 1-year survival is noticed. The 2-year survival, however, appears still to be increasing. In a Cox proportional hazards model the following variables were found to be independent predictors for survival: age at diagnosis, earliest clinical AIDS manifestations, year of diagnosis and HIV risk group. No differences were seen in the 1 and 2-year survival probabilities for men and women with AIDS. Heterosexual men and women tended to have a poorer survival than intravenous drug users and homosexual and bisexual men.

CONCLUSION

A noticeable improvement in the survival probability with time occurred for AIDS patients living in the Amsterdam region through the years 1982-1991, although the overall survival after AIDS diagnosis is still poor. The 1-year survival appears to have reached a plateau, the 2-year survival is still increasing. Improved clinical experience, awareness of HIV related complaints in high risk groups, better diagnostic methods and the availability of proper medication (prophylactic and treatment) are the most likely explanations of the improvement in survival.

Impact of AIDS on premature mortality in Amsterdam, 1982-1992

OBJECTIVE

To study the impact of AIDS on premature mortality in the city of Amsterdam (1982-1992).

METHODS

We combined aggregated data from the Netherlands Central Bureau for Statistics with data from the municipal death and population registry and data from the Amsterdam AIDS surveillance system to calculate age standardized mortality rates for men aged 15-64 years and 25-54 years and working years of potential life lost before 65 years (WYPLL).

RESULTS

AIDS was the leading cause of death for men aged 25-54 years in Amsterdam from 1990 onwards, and the third leading cause of death for men aged 15-64 years in 1991. In this larger age group AIDS will probably become the leading cause of death in the coming years. In 1991, AIDS was already the leading cause of WYPLL before 65 years for men in the 15-64 age group. Without AIDS, there would have been a decrease in premature WYPLL from 1982 onwards; however, because of AIDS the number of WYPLL is increasing again.

CONCLUSION

AIDS has had a significant impact on the pattern of premature mortality in Amsterdam in the period 1982-1992. Its impact will probably increase over the next few years.

[AIDS epidemiology in The Netherlands in persons infected through heterosexual contact]

Ten years after the start of the AIDS epidemic in the Netherlands the proportion of persons infected by heterosexual contacts among the total of AIDS cases diagnosed is small (7.4%). Up to December 1991 the cumulative totals of females and males in the Netherlands reported with the diagnosis and infected by heterosexual contact were 55 and 93, respectively. Of the 55 heterosexual females, 69% had the Dutch nationality, of the 93 heterosexual males, 67%. Considerable proportions of the numbers of AIDS patients in this group (males 47%, females 45%) were diagnosed in the four largest cities (Amsterdam, Rotterdam, The Hague and Utrecht). The remaining cases of AIDS diagnosed in this group were scattered throughout the country. Among heterosexual females a gradual increase of the number of AIDS cases diagnosed was observed since 1985. In the males there was no clear trend in the number of diagnoses since 1984. Of the 55 females, 19 originated from an area endemic for AIDS or had had sexual contacts with a person from such a region (34.6%). Among the 93 males this number was 29 (31.2%). Nineteen of the 55 females (34.6%) were known to have sexual contact with a person from the known risk groups. The same held true of 12 males (12.9%). Of the remaining 17 females (30.9%) and 52 males (55.9%) it was only known that they were heterosexual without further risk factors or risk contacts.(ABSTRACT TRUNCATED AT 250 WORDS)

Short-term predictions of HIV prevalence and AIDS incidence

Reports of AIDS cases in Amsterdam up to February 1990 were used to make predictions of future cases up to 1993. Two published methods were applied, which make extrapolations from current cases and simultaneously estimate the extent of delay in reporting. The choice of the exact model greatly influenced the predictions, as did predictions for distinct transmission groups. We present results for the homo/bisexual male group, and the total population of Amsterdam. The AIDS case predictions are used to predict the HIV prevalence using the ratio of HIV prevalence to AIDS incidence and through 'back calculation'. We suggest that the ratio is a simple technique that may be used to estimate HIV prevalence. The estimated number of cumulative HIV infected homo/bisexual males in Amsterdam in January 1990 was between 2100 and 4100 in a total of 2200-4600 infected people.

[Estimate of the number of HIV-infected intravenous drug users in Amsterdam]

By combining data collected through a cohort study among injecting drug users (IDUs), which started December 1985, with data on the number of notified cases of AIDS, the cumulative number of HIV-infected IDUs residing in Amsterdam was estimated. The estimated cumulative incidence of HIV-infection among IDUs in Amsterdam on 1 July 1991 was about 1050. By 1 July 1991 90 of these cases had been diagnosed with AIDS, while an estimated 150-200 cases died before AIDS had been diagnosed. The prevalence of IDUs residing in Amsterdam who were still alive and free of AIDS on 1 July 1991 was estimated to be about 750-800. Because of untimely deaths, only a limited number of these HIV-infected IDUs can be expected to be diagnosed with AIDS in the future. The prevalence on 1 July 1991 of HIV-infected IDUs being alive and free of (diagnosed) AIDS and living elsewhere in the Netherlands is estimated at about 500.

[Results of screening for HIV antibodies in pregnant women, clients of infertility clinics and abortion clinics in the Amsterdam region in 1990]

In 1988, a study was started in three Amsterdam hospitals to investigate the HIV prevalence among pregnant women. In 1989 more hospitals and also midwife clinics were included in the study. From 1990 onwards all hospitals in Amsterdam, 22 midwife practices, 2 abortion clinics and 3 clinics for infertility problems participated. The study was carried out on a voluntary basis. Of the 8423 eligible pregnant women in 1990, 7823 women (92.9%) participated and 600 women (7.1%) decided not to participate. Eight women were found to be positive for HIV antibodies (0.10%, 95% CI 0.09-0.11) (1988: 0.28%; 1989: 0.10%). Of these 8 HIV-seropositive women 5 belonged to one of the known AIDS risk groups and 3 women were not aware of any risk-bearing behaviour. Of the 5 women from an AIDS risk group 2 denied a risk factor at their first visit to the clinic. One of the 8 women was positive for antibodies against HIV-2. Among the 719 women tested in the abortion clinics (23.3% refusers) 3 women were positive for antibodies against HIV-2 and I woman against HIV-I (prevalence 0.56%; 95% CI 0.52-0.59). Of the 476 women tested in the clinics for infertility problems no women were found positive for HIV antibodies. During the period 1988-1990, a total of 19 women were found HIV-seropositive in the screening program for pregnant women. Of the 13 women tested within the first 20 weeks of pregnancy 4 women decided to terminate their pregnancy.(ABSTRACT TRUNCATED AT 250 WORDS)

[Benefit of the serological screening program for syphilis in pregnant women in Amsterdam in the period 1985-1989]

The results of the serological syphilis screening programme for pregnant women in the region of Amsterdam in the period 1985-1989 are described. In addition, a cost-benefit analysis was done to determine useful effects of the programme. Every GP and obstetrician routinely takes blood samples from pregnant women to determine the blood group, rhesus factor and syphilis serology. In the period 1985-1989, a total of 37,520 serum samples were screened for syphilis in the Amsterdam region by the Central Laboratory of the Blood Transfusion Service (until mid-1986) and by the Regional Public Health Laboratory of the Municipal Health Service (from mid-1986). In 55 women (0.15%) both the Treponema pallidum haemagglutination assay (TPHA) and the venereal disease research laboratory (VDRL) tests were positive. Further evaluation of these 55 women ultimately brought to light 10 women with positive syphilis serology who had not been treated and consequently might infect their child with Treponema pallidum. Considering the various transmission percentages of the bacterium from mother to foetus, which depend on the stage of the maternal infection, the screening programme has prevented two cases of congenital syphilis. This brings the cost-benefit ratio of the syphilis screening programme for the region of Amsterdam to 1:6.2. In view of these findings there is no reason to reconsider the current screening practice in Amsterdam.

Trends in mortality among AIDS patients in Amsterdam, 1982-1988

In this study we evaluated the survival of 515 AIDS patients diagnosed in Amsterdam between 1982 and 1988 and followed-up until April 1990. Non-resident patients survived for a shorter period than resident patients (median survival time 10 versus 16 months). Residents had a 1-, 2- and 3-year survival of 56.1, 33.0 and 17.2%, respectively. Heterosexual intravenous drug users tended to have a better survival than homosexual men, although this was not significant. The survival time was longer for AIDS patients less than 30 years of age at diagnosis and varied for the different clinical manifestations leading to AIDS diagnosis. We calculated the 1- and 2-year survival probability by year of diagnosis for patients initially presenting with a Pneumocystis carinii pneumonia (PCP). The 1-year survival improved greatly in 1986 and continued to rise in the following years. The 2-year survival was similar in 1986 and 1987 (26.8 versus 28.2%) but increased in 1988 (38.9%). We conclude that besides better clinical experience and diagnostic methods, this improvement in prognosis could be explained by the start of secondary prophylaxis for PCP in 1985 and the introduction of zidovudine therapy in 1987.

[Analysis of antibodies against human immunodeficiency virus on a voluntary basis in healthy persons in Amsterdam 1988 and 1989]

At the Municipal Health Service of Amsterdam it is possible to be tested for HIV antibodies after signing an informed consent. In 1988, 1247 persons were tested (797 men, 450 women) and in 1989, 1400 persons (869 men, 531 women). Fifty-eight persons were identified as HIV-seropositive for the first time (1988: 24 men, 3 women; 1989: 28 men, 3 women). All but one woman belonged to a risk group or had had sexual contact with a person from a known risk group. In 1989 no increase in the percentage of HIV-seropositive persons was seen. In our (selected) group of persons in 1988 and 1989 we saw no transmission of HIV outside the known risk groups.

[The epidemiology of AIDS in Amsterdam, 1982-1988]

The results are reported of AIDS monitoring in Amsterdam in the period 1982-1988. Males with homosexual contacts are the principal risk group followed by the fast-growing group of users of intravenous drugs. Transmission of the human immunodeficiency virus to the heterosexual population will occur mostly via sexual contacts with users of drugs. An investigation of the degree of underreporting in Amsterdam revealed 23 unreported patients (5.7% of the cumulative total). The median duration of survival of AIDS patients increased: 1982-1985, 9 months, 1986, 12 months, 1987, 16 months. Two-year survival of patients in the periods 1986 and 1987 was practically the same, however. It is assumed that at the end of 1991, 1124 AIDS patients domiciled in Amsterdam will have been diagnosed.