Erik van Ameijden

Human immunodeficiency virus infection and other risk factors for skin abscesses and endocarditis among injection drug users.

OBJECTIVE To study incidence rates of and risk factors for skin abscesses at the site of injection and episodes of endocarditis among injection drug users (IDU). DESIGN A comprehensive, open cohort study of drug users on the natural history of human immunodeficiency virus (HIV) infection. METHODS From 1986 to 1994, injection drug users in Amsterdam were included in the study. Incidence rates of self-reported skin abscesses and verified episodes of endocarditis were calculated. In uni- and multivariate Poisson regression analysis, risk factors for skin abscesses and endocarditis were determined. RESULTS 521 HIV-seronegative and 237 HIV-seropositive IDU were followed for 1640 person-years. A total of 545 skin abscesses were reported by 269 IDU (incidence 33/100 person-years). HIV infection, female gender, prostitution among females, foreign nationality, injection of heroin and cocaine, a high frequency of injecting, and obtaining syringes through the needle exchange program were independently and positively associated with skin abscesses. During follow-up, 17 verified episodes of endocarditis were observed (incidence 1.3/100 person-years). Endocarditis was independently associated with HIV infection and a previous history of endocarditis. Furthermore, women and IDU with a skin abscess appeared to be at an increased risk for endocarditis. CONCLUSIONS HIV infection is an independent risk factor for skin abscesses and endocarditis. Also, women are at an increased risk for these injection-related infections. Prevention activities, like promotion of skin cleaning, should be directed at those IDU in whom one or more risk factors have been identified.

The Utrecht Health Project: Optimization of routine healthcare data for research

BackgroundResearch on the impact of changes in healthcare policy, developments in community and public health and determinants of health and disease during lifetime may effectively make use of routine healthcare data. These data, however, need to meet minimal criteria for quality and completeness. Research opportunities are further improved when routine data are supplemented with a standardized ‘baseline’ assessment of the full population. This formed the basis for a new study initiated in a newly developed large residential area in Leidsche Rijn, part of the city of Utrecht, the Netherlands.MethodsAll new inhabitants are invited by their general practitioner to participate in the Utrecht Health Project (UHP). Informed consent is obtained and an individual health profile (IHP) is made by dedicated research nurses. The IHP is the starting point for the UHP research database as well as for the primary care electronic medical records. Follow-up data are collected through continuous linkage with the computerized medical files recorded by the general practitioners. UHP staff in each practice takes care of quality management of registration as well as data handling.ResultsCurrently, over 60 of invited new residents in the area have given informed consent with participation steadily increasing.DiscussionThe Utrecht Health Project combines key elements of traditional epidemiologic cohort studies with the current power of routine electronic medical record keeping in primary care. The research approach optimizes routine health care data for use in scientific research.

HIV surveillance among sexually transmitted disease clinic attenders in Amsterdam, 1991-1996.

Objective:To determine trends in HIV prevalence among attenders of a clinic for sexually transmitted diseases (STD), with emphasis on heterosexuals who did not have a history of injecting drug use. Methods:Anonymous unlinked HIV surveys with individual consent, conducted each half year from 1991 to 1996 (except 1993) among STD clinic attenders who came for evaluation of a possible new STD episode. Results:Of 10 940 eligible attenders 10 046 (92%) accepted HIV testing. Of all tested attenders, 312 (3.1%) were HIV-infected. Overall HIV prevalence decreased significantly from 4.6% in 1991 to 2.8% in 1996. HIV prevalence among heterosexual men and women who were not injecting drug users was less than 1% in all but one survey period. Except for one woman, none of the 48 HIV-infected heterosexuals was aware of their current serostatus. Among HIV-infected heterosexuals, 21 out of 28 males (75%) and 18 out of 20 females (90%) were of non-Dutch origin. HIV prevalence was 16% among all homosexual men, and 12% among young homosexual men aged < 30 years. HIV prevalence among young homosexual men decreased significantly over time. Among HIV-infected homosexual men, 58% of older men and 59% of younger men were not aware of their current HIV infection. Rates of current STD were generally significantly higher among HIV-infected participants compared with non-HIV-infected participants. Conclusions:Although HIV prevalence among heterosexual clinic attenders is low, there is a clear potential for ongoing sexual HIV transmission. Most heterosexually acquired HIV infections are found in non-Dutch persons. This observation suggests migration of HIV-infected heterosexuals or the separation of Dutch and non-Dutch heterosexual networks. Awareness of serostatus is almost non-existent among HIV-infected heterosexuals, and is low among male homosexual clinic attenders. To increase awareness of current HIV serostatus and possibly decrease risk behaviour, HIV counselling and testing should be offered actively to all clinic attenders.

HIV prevalence and risk behaviour in young drug users in Amsterdam.

Objectives To assess the HIV prevalence and risk behaviour among regular young drug users (YDU) in Amsterdam. Design Subjects were 282 YDU (using heroin, cocaine, methadone and/or amphetamines at least 3 days/week) aged 30 years or less who participated in a cross-sectional survey in Amsterdam in 1998. Participants were recruited both directly (41%) through healthcare institutions, and indirectly (59%) by referrals from YDU already enrolled. A comparison sample of YDU from the Amsterdam Cohort Study recruited between 1985 and 1989 was used to describe trends in HIV prevalence and risk behaviour. Results Mean age was 25 years, 22% were women, 39% had at least once injected drugs, and 22% currently injected in 1998. Cocaine was more often used regularly (70%) than heroin (42%). Of the 282 YDU, 21 (7.4%) were infected with HIV. Among those who had injected drugs, HIV prevalence was 16.2%. Among those who had never injected, the prevalence of HIV infection was 1.8%. A history of injecting declined from 83% in 1985–1989 to 56% in 1998. Compared with 1985–1989, the lack of a recent steady partner appeared to be an important risk factor for a positive HIV status among injectors in 1998, whereas borrowing of used needles/syringes was no longer a risk factor. Conclusion The use of cocaine among YDU is very popular in Amsterdam. A strong decrease in injecting behaviour has taken place, but among those who inject, risk behaviour is still considerable, and HIV infection is still widespread. Preventative activities should be expanded, specifically among YDU.

Transitions in drug use in a new generation of problem drug users in Amsterdam: a 6-year follow-up study.

Aims: This study describes the transitions in drug use in Amsterdam among young drug users (YDUs) who are inhaling or injecting cocaine or using illicitly obtained opiates. Methods: From 2000 until 2003, 187 YDUs (≤30 years) were recruited of whom 126 were followed into 2007. Results: During the 6 months prior to inclusion, 95% used cocaine, 60% used illicit opiates, and 9% injected more than once a week. During follow-up, the incidence of new-onset heroin use was 4.8/100 person-years. The incidence of injecting was much lower for never-injectors (2.1/100 person-years) than for ever-injectors who relapsed (13.2/100 person-years). Transition to abstinence or nonfrequent drug use is common (23/100 person-years), mostly followed by a relapse (73/100 person-years). Polydrug users were less likely to discontinue their frequent drug use than monodrug users. Conclusions: Treatment services should target the crack cocaine users to prevent further marginalization and, during abstinence, to prevent relapse. Although the prevalence and incidence of injecting are relatively low, it is still an option for opiate users, especially those with a history of injecting.

Methadone maintenance treatment modalities in relation to incidence of HIV: results of the Amsterdam cohort study.

STUDY OBJECTIVE To evaluate methadone maintenance treatment modalities, prescribed within the concept of harm reduction, in relation to incidence of HIV infection among drug users with a history of methadone treatment in Amsterdam, The Netherlands. DESIGN Prospective observational cohort study among 582 HIV-negative drug users. To ensure valid and detailed assessment of methadone treatment, data from the Central Methadone Register in Amsterdam were linked to the Amsterdam cohort study among drug users. METHODS Poisson regression analysis was used to identify independent and significant predictors of incidence of HIV. MAIN RESULTS During 1906 person years, 58 drug users seroconverted, the overall incidence of HIV being 3.0 per 100 person years with a declining trend for current injectors. An increase in frequency of methadone programme attendance [relative risk (RR), 2.4; 95% confidence interval (CI), 1.2-4.6, compared with no change] and increase in methadone dosage (RR, 0.8; 95% CI, 0.6-1.0, per category of change of 10 mg/day) were significantly associated with incidence of HIV in multivariate analysis. Methadone dosage and frequency of programme attendance in itself were not significant predictors. Other multivariate significant risk factors were homelessness, current injecting and in-patient hospital care. CONCLUSIONS Among drug users who receive methadone maintenance treatment in a harm-reduction setting, which includes ancillary services such as needle-exchange programmes and HIV testing and counselling, prescription of high methadone dosages is not sufficient to stop the spread of HIV. However, an individual increase of the methadone dosage and measures to achieve high treatment retention could contribute to the prevention of HIV among drug users.

Why investigate urban health indicators

Globally, the majority of people now live in urban areas.1 The European Urban Health Indicator System projects parts 1 and 2 (EURO-URHIS 1 and 2) have been developing tools to help policy-makers determine the health, and ways to improve the health, of urban dwellers. The focus of policy-makers should not just be on a narrow health perspective but also on the need to improve the environment, social status and quality of life of urban populations by all means possible. Descriptive studies at urban and sub-urban level which measure the extent of problems and monitor progress, and population-based interventions, are essential to ensure the sustainability of healthy urbanization and the wellbeing of urban citizens. Multidisciplinary, trans-sectoral research into evidence-based policy-making, i.e. from bench to populations, is the only way to bring about real health gain for the global urban resident. ‘Health is wealth’ must be the rallying cry for all urban policy-makers. In 1978, the United Nations (UN) recognized that the urban environment was a global challenge and created the Human Settlements Programme, or UN-Habitat, for sustainable settlement development and adequate shelter for all. Thirty years later, the urban population has now exceeded the rural population and become poorest subset of the World’s population.2 The movement of populations into urban areas (UAs) is due in part to the drive to achieve better general socioeconomic, cultural and environmental conditions. However, it has led to an expansion of urban environments known as ‘urban sprawl’. UAs can be split into many different zones depending on the functionality and density of the infrastructure and environment, e.g. urban heart or ‘city centre’, industrial and commercial zones, and suburban areas which are mostly residential or mixed function.3,4 The resultant variation in urban environments means it is often difficult to define the ‘city’ …

The effect of urban-area unemployment on the mental health of citizens differs between Slovak and Dutch cities

Conclusive evidence on the association of mental health problems (MHP) with area unemployment is lacking in regard to Central European cities. We obtained data on residents aged 19-64 from Slovak and Dutch cities from the FP7 EURO-URHIS 2 project. Multilevel logistic regression showed that the association between MHP (GHQ-12-total score ≥2) and area unemployment was strong in the Netherlands, but absent in Slovakia. Slovak citizens from the most favourable neighbourhoods had nearly double the risk of MHP than their Dutch counterparts. Individual-level socioeconomic characteristics did not explain area differences. The effect of urban-area unemployment seems to differ between Central European and Western European countries.

Health-risk behaviours in deprived urban neighbourhoods: a comparison between Slovak and Dutch cities

ObjectivesInternational comparisons of the associations of area-level socioeconomic position (SEP) and health-risk behaviours (HRBs) are for the most part lacking. The aims of this study were to compare Slovakia and the Netherlands regarding differences in the prevalence of HRBs by neighbourhood and individual deprivation, and to determine whether area differences could be explained by the SEP of residents.MethodsWe obtained data on residents aged 19–64 from Slovak and Dutch cities from the FP7 EURO-URHIS2 project and employed multilevel logistic regression.ResultsThe association between neighbourhood-level unemployment and HRBs differed between countries. In the Netherlands, the prevalence of almost all HRBs was higher in deprived areas, except for the consumption of fruits and vegetables. These area effects diminished after controlling for individual-level SEP. In Slovakia, no area effects were observed, although Slovak residents showed a higher risk for most HRBs. At the individual level, an inverse SE gradient was found for almost all HRBs in both countries.ConclusionsLocal analyses of small area health differences and health determinants are critical for efficient implementation of neighbourhood-based interventions.

Gender differences in clinical manifestations before AIDS diagnosis among injecting drug users

We compared incidence rates of self-reported HIV-related symptoms and illnesses, verified clinical manifestations and findings on physical examination between female and male injecting drug users (IDU) stratified by HIV serostatus in the Amsterdam cohort study on the natural history of HIV infection. HIV-positive female IDU (n = 100) reported a higher frequency of several symptoms and illnesses than male IDU (n = 139). Symptoms were reported more chronically by women compared to men, while clinical manifestations were reported by a greater proportion of women affected by these illnesses compared to men. In HIV-negative IDU (163 women and 232 men) the incidence rates were lower compared to HIV-positives, and a similar gender effect on reported symptoms and illnesses was found. Adjusting for biological, behavioral, demographic and study related variables did not change the gender effect on clinical manifestations substantially. We conclude that the gender effect among HIV-positive IDU was not caused by a differential impact of HIV infection on the incidence of the studied clinical manifestations among female and male IDU, but reflects a higher morbidity of female IDU compared to male IDU.