Incentive payments may reduce time for clinical care.
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Humans↗
Biomedical subjects
M Rickenbach
Publications and source records attributed to M Rickenbach.
Acute HIV infection: impact on the spread of HIV and transmission of drug resistance.
OBJECTIVE: To assess the impact of primary HIV infection (PHI) on the spread of HIV and the temporal trends in transmission of HIV drug resistance between 1996 and 1999 in Switzerland. METHODS: Sequencing of the genes for reverse transcriptase (RT) and protease was performed for 197 individuals with documented PHI. Phylogenetic analyses were confronted with epidemiological data. RESULTS: Significant clustering was demonstrated for 29% of the RT sequences. All these cases occurred closely together in place and time; contact tracing demonstrated transmission at the time of PHI in 30% of them. Genotypic drug resistance was detected in 8.6% of PHI individuals in 1996, 14.6% in 1997, 8.8% in 1998 and 5.0% in 1999. Drug-resistant variants were identified in 11.3% of individuals infected by homosexual contacts, 6.1% by heterosexual contacts, 13% of intravenous drug users and more frequently in men (10.4%) than women (2.6%). Potential factors involved in the recent decrease of transmission of drug-resistant variants include increase of HIV non-B subtypes from 23% in 1996 to 35% in 1999 (only one non-B subtype had resistance mutations) and a steady increase of patients with undetectable viraemia as documented in Swiss HIV Cohort Study (10% in 1996 vs 53% in 1999). CONCLUSIONS: Phylogenetic and epidemiological analyses underline the impact of PHI in the spread of HIV. Moreover, this study indicates that drug resistance transmission may have decreased recently in Switzerland through the increased frequency of infection with HIV non-B subtypes and the steady increase of patients with undetectable viraemia.
Acute Disease↗
Importance of mental health assessment in HIV-infected outpatients.
HIV infection, even when well controlled, may be associated with important mental health problems. We sought to investigate anxiety, depression, and health-related quality of life using screening measurements in patients with HIV infection and to examine their dependency on biosocial parameters relating to HIV. Prospective clinical, virologic, and immunologic data were obtained in a cross-sectional study within the Swiss HIV Cohort Study. Four self-reported questionnaires were used in 397 HIV-infected individuals. The scores for anxiety and depression were high as measured by the Hospital Anxiety and Depression Scale (HADS) and the State Trait Anxiety Inventory (STAI). Half the population scored <75 on a visual analog scale (VAS) Patients were also affected in their quality of life as measured by the HIV Medical Outcome Study (HIV-MOS). Almost all scores were significantly worse for intravenous drug users compared with other transmission groups. People who were employed, with a higher education or with higher CD4 count tended to score better, whereas those who had been hospitalized within the last 6 months, infected for a longer time, with higher viral load, or loss of weight scored significantly worse. A multivariate analysis showed higher education, being employed, low viral load, female gender, and shorter HIV disease duration to be associated with better scores. This study highlights the importance of mental health assessment regardless of HIV-disease parameters.
Adolescent↗
Hyperlactatemia and antiretroviral therapy: the Swiss HIV Cohort Study.
The prevalence, clinical presentation, and risk factors for hyperlactatemia among patients receiving antiretroviral therapy was determined during a 1-month period for patients in the Swiss HIV Cohort Study. Overall, 73 (8.3%) of 880 patients presented an increase in serum lactate of >1.1 times the upper normal limit (UNL). For 9 patients (1%), lactate elevation was moderate or severe (>2.2 times the UNL). Patients who presented with hyperlactatemia were more likely to be receiving stavudine with or without didanosine (odds ratio, 2.7; 95% confidence interval, 1.5-4.8), as compared with patients who received zidovudine-based regimens. The risk increased with increasing time receiving stavudine with or without didanosine. The association between hyperlactatemia and stavudine with or without didanosine was not biased by these medications being more recently available and, therefore, being given preferentially to patients who had prolonged use of nucleoside analog reverse-transcriptase inhibitors. Hyperlactatemia was associated with lipoatrophy, hyperlipidemia, and hyperglycemia. Age, sex, or stage of infection with human immunodeficiency virus were not predictive of hyperlactatemia. Determination of lactate levels may prove useful in the screening for mitochondrial toxicity.
Acidosis, Lactic↗
Disseminated M. avium complex infection in the Swiss HIV Cohort Study: declining incidence, improved prognosis and discontinuation of maintenance therapy.
BACKGROUND: Introduction of potent antiretroviral combination therapy (ART) has reduced overall morbidity and mortality amongst HIV-infected adults. Some prophylactic regimes against opportunistic infections can be discontinued in patients under successful ART. QUESTIONS UNDER STUDY: (1) The influence of the availability of ART on incidence and mortality of disseminated M. avium Complex infection (MAC). (2) The safety of discontinuation of maintenance therapy against MAC in patients on ART. SETTING: The Swiss HIV-Cohort Study, a prospective multicentre study of HIV-infected adults. METHODS: Patients with a nadir CD4 count below 50 cells/mm3 were considered at risk for MAC and contributed to total follow-up time for calculating the incidence. Survival analysis was performed by using Kaplan Meier and Cox proportional hazards methods. Safety of discontinuation of maintenance therapy was evaluated by review of the medical notes. RESULTS: 398 patients were diagnosed with MAC from 1990 to 1999. 350 had a previous CD4 count below 50 cells/mm3. A total of 3208 patients had a nadir CD4 count of less than 50 cells/mm3 during the study period and contributed to a total follow-up of 6004 person-years. The incidence over the whole study period was 5.8 events per 100 person-years. In the time period of available ART the incidence of MAC was significantly reduced (1.4 versus 8.8 events per 100 person-years, p < 0.001). Being diagnosed after 1995 was the most powerful predictor of better survival (adjusted hazard ratio for death: 0.27; p < 0.001). None of 24 patients discontinuing maintenance therapy while on ART experienced recurrence of MAC during a total follow-up of 56.6 person-years (upper 95% confidence limit 5.3 per 100 person-years). CONCLUSION: Introducing ART has markedly reduced the risk of MAC for HIV-infected individuals with a history of very low CD4 counts. Survival after diagnosis of MAC has improved after ART became available. In patients responding to ART, discontinuation of maintenance therapy against M. avium may be safe.
AIDS-Related Opportunistic Infections↗
Discontinuation of primary prophylaxis in HIV-infected patients at high risk of Pneumocystis carinii pneumonia: prospective multicentre study.
OBJECTIVES: To assess the safety of discontinuation of primary prophylaxis in HIV-infected patients on antiretroviral combination therapy at high risk of developing Pneumocystis carinii pneumonia. DESIGN: Prospective multicentre study. PATIENTS AND METHODS: The incidence of P. carinii pneumonia after discontinuation of primary prophylaxis was studied in 396 HIV-infected patients on antiretroviral combination therapy who experienced an increase in their CD4 cell count to at least 200 x 10(6)/l and 14% of total lymphocytes; the study population included 191 patients with a history of CD4 cell counts below 100 x 10(6)/l (245 person-years) and 144 patients with plasma HIV RNA above 200 copies/ml (215 person-years). RESULTS: There was one case of Pneumocystis pneumonia, an incidence of 0.18 per 100 person-years [95% confidence interval (CI), 0.005--1.0 per 100 person-years]. No case was diagnosed in groups with low nadir CD4 cell counts (95% CI, 0--1.2 per 100 person-years) or detectable plasma HIV RNA (95% CI, 0--1.4 per 100 person-years). CONCLUSIONS: Discontinuation of primary prophylaxis against Pneumocystis pneumonia is safe in patients who have responded with a sustained increase in their CD4 cell count to antiretroviral combination therapy, irrespective of the CD4 cell count nadir and the viral load at the time of stopping prophylaxis.
Adult↗
Assessment of physical activity in population surveys.
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Activities of Daily Living↗
Body mass index: comparing mean values and prevalence rates from telephone and examination surveys.
BACKGROUND: Cost effective means of assessing the levels of risk factors in the population have to be defined in order to monitor these factors over time and across populations. This study is aimed at analyzing the difference in population estimates of the mean levels of body mass index (BMI) and the prevalences of overweight, between health examination survey and telephone survey. METHODS: The study compares the results of two health surveys, one by telephone (N=820) and the other by physical examination (N=1318). The two surveys, based on independent random samples of the population, were carried out over the same period (1992-1993) in the same population (canton of Vaud, Switzerland). RESULTS: Overall participation rates were 67% and 53% for the health interview survey (HIS) and the health examination survey (HES) respectively. In the HIS, the reporting rate was over 98% for weight and height values. Self-reported weight was on average lower than measured weight, by 2.2 kg in men and 3.5 kg in women, while self-reported height was on average greater than measured height, by 1.2 cm in men and 1.9 cm in women. As a result, in comparison to HES, HIS led to substantially lower mean levels of BMI, and to a reduction of the prevalence rates of obesity (BMI>30 kg/m(2)) by more than a half. These differences are larger for women than for men. CONCLUSION: The two surveys were based on different sampling procedures. However, this difference in design is unlikely to explain the systematic bias observed between self-reported and measured values for height and weight. This bias entails the overall validity of BMI assessment from telephone surveys.
Adult↗
Drug resistance mutations in HIV-1-infected subjects during protease inhibitor-containing highly active antiretroviral therapy with nelfinavir or indinavir.
OBJECTIVES: The aim of this retrospective study was to evaluate treatment outcome and characterize the pattern of genotype mutations in subjects with treatment failure on highly active antiretroviral therapy (HAART) containing nelfinavir or indinavir. STUDY DESIGN AND METHODS: The database of the Swiss HIV Cohort Study was screened for all subjects naive to protease inhibitor (PI) treatment who started HAART with nelfinavir or indinavir, responded initially (HIV-RNA <400 copies/ml) and received >24 weeks of treatment. Responders with subsequent treatment failure (HIV-RNA >1000 copies/ml, bordered by HIV-RNA >400 copies/ml) were selected for genotypic analysis. RESULTS: Initial treatment response, maintenance of response and subsequent virological failure were observed at a comparable frequency in 1143 nelfinavir and 1555 indinavir subjects. Of the treatment-naive patients, 13% who took nelfinavir and 16% who took indinavir had HIV-RNA >1000 copies/ml at least once. These values increased to 24 and 27%, respectively, for reverse transcriptase inhibitor-experienced subjects. Genotypic analysis in a subset of subjects with virological failure identified 30N as the only primary mutation in the nelfinavir subjects (8 out of 21, 38%) whereas isolated or combined 82A/T and 461/L mutations were detected in the indinavir subjects (9 out of 20, 45%). CONCLUSIONS: In this population of previously PI-naive subjects, the rate of virological failure and the frequency of resistance mutations at the time of virological failure were comparable in subjects receiving nelfinavir- or indinavir-containing HAART. In nelfinavir subjects, 30N was the only primary mutation whereas isolated or combined 82A/T and 461/L mutations were detected in indinavir subjects.
Acquired Immunodeficiency Syndrome↗
Clinical epidemiology and research on HIV infection in Switzerland: the Swiss HIV Cohort Study 1988-2000.
BACKGROUND AND OBJECTIVES: The Swiss HIV Cohort Study (SHCS) was initiated in 1988 and represented the main scientific component of the comprehensive response to the AIDS epidemic in Switzerland. It brought together physicians and scientists from five university hospitals (Basel, Berne, Geneva, Lausanne and Zurich) and two Cantonal hospitals (Lugano and St. Gallen). The objective of SHCS was, and still is, to produce rapid, high quality patient-oriented medical research in the field of HIV infection. METHODS: SHCS is a prospective population-based cohort study. Any HIV-infected person aged > or = 16 years is eligible to participate. Data collection and study procedures are standardised. Data quality and protocol monitoring are conducted at the coordination and data centre in Lausanne. Detailed information on demographics, income, mode of HIV acquisition, risk behaviours, clinical events, laboratory results, treatment and treatment tolerance is collected at registration and at 6-monthly intervals. RESULTS: Since 1996, 10,600 persons have been enrolled and the SHCS study population is considered fairly representative of the HIV-infected population in Switzerland, at least in terms of gender and mode of HIV acquisition. In 1999, 4600 patients were actively followed up and more than 70% of patients were receiving highly active antiretroviral therapy (HAART). As a consequence, mortality and the incidence of HIV-related opportunistic infections have decreased significantly in the recent past. Between 1996 and 2000, 91 original manuscripts have been published by SHCS scientists and physicians, almost exclusively in peer-reviewed journals. A wide range of scientific questions have been addressed, including HIV primary infection, the natural history of HIV infection, the clinical and biological impact of HAART, drug resistance, risk factors for disease evolution including the timing of treatment initiation, the role of CD4 receptors, the validity of HIV surveillance reports, determinants of treatment access and tolerance, clinical trials of new drug combinations, the interruption of prophylaxis following a favourable response to HAART and issues relating to quality of life and interaction between income, social level and disease evolution. CONCLUSION: The SHCS has had, and continues to have, a significant impact on medical practice, public health and research in Switzerland and beyond. It represents a network of excellence which has brought together and fostered intensive collaboration between physicians and institutions throughout this country and beyond. This was possible thanks to the support of the Federal Office of Public Health and the commitment of primary care physicians, researchers and patients. This project may be model for focused and prioritised multicentre and transdisciplinary research programmes.
AIDS-Related Opportunistic Infections↗
One-year prevalence of low back pain in two Swiss regions: estimates from the population participating in the 1992-1993 MONICA project.
STUDY DESIGN: A cross-sectional survey was performed. OBJECTIVE: To estimate the extent of low back pain as a public health problem. SUMMARY OF BACKGROUND DATA: Health surveys converge on very high estimates of low back pain in general populations, but few studies have included severity criteria in their definition and conclusions. Because it is unlikely that interventions will influence the prevalence of minimal and infrequent symptoms, greater attention should be paid to characteristics of low back pain that indicate some impact on the life of survey respondents. METHODS: Two regions participated in the MONICA (MONitoring of trends and determinants in CArdiovascular disease) project in Switzerland. Participants randomly selected from the general population completed a standard self-administered questionnaire on cardiovascular risk factors. A special section on low back pain was added in the third (1992-1993) MONICA survey and completed by 3227 participants. RESULTS: A regional difference found in the 12-month prevalence rate disappeared with the inclusion of severity criteria. Low back pain over more than seven cumulated days was reported among men by 20.2% (age range, 25-34 years) to 28.5% (age range, 65-74 years), respectively, among women by 31.1% to 38.5%. Similar rates of reduction in activity (professional, housekeeping, and leisure time) and medical consultation (conventional and nonconventional) motivated by low back pain characterized the two participating regions. The cumulative duration of pain was related to all the indicators showing the impact of low back pain on everyday life. CONCLUSIONS: Determining the cumulative duration of low back pain over the preceding year is a straightforward task, and a cutoff at 1 week seems appropriate for distinguishing between low- and high-impact low back pain.
Adult↗
Effect of antiretroviral therapy on viral load, CD4 cell count, and progression to acquired immunodeficiency syndrome in a community human immunodeficiency virus-infected cohort. Swiss HIV Cohort Study.
OBJECTIVE: To examine the effect of different antiretroviral treatment regimens on viral load, CD4 lymphocyte counts, and rates of progression to clinical acquired immunodeficiency syndrome events among treatment-naive human immunodeficiency virus (HIV)-infected patients enrolled in a large community cohort study. METHODS: Based in 7 outpatient clinics, the Swiss HIV Cohort Study is a cohort with national coverage. Virological, immunologic, and clinical results of 755 treatment-naive patients (median age, 36 years; 28.2% female) who initiated antiretroviral therapy between July 1, 1995, and June 30, 1997, were analyzed. Patients started undergoing monotherapy with 1 reverse transcriptase inhibitor (RTI), combination therapy with at least 2 RTIs, or highly active antiretroviral therapy (HAART) with RTIs and protease inhibitors. RESULTS: Antiretroviral treatment led to a mean reduction of viremia of 1.8 log10 copies per milliliter with HAART, 1.2 log10 copies per milliliter with RTI combination therapy, and 0.4 log10 copies per milliliter with monotherapy. Virological failure, defined as less than 1 log10 reduction per milliliter in viremia, was present in 45 (20%) patients undergoing HAART, 180 (38%) undergoing RTI combination therapy, and 47 (82%) undergoing monotherapy. The proportion of patients reaching undetectable viremia was 12% (n = 7) for monotherapy, 41% (n = 197) for RTI combination therapy, and 63% (n = 137) for HAART. Similar gains of CD4 cells were achieved with RTI combination therapy and HAART. Kaplan-Meier estimates of progression rates to a new acquired immunodeficiency syndrome event at 18 months were 13.6% (monotherapy), 4.7% (RTI combination therapy), and 3.9% (HAART). CONCLUSIONS: The rate of virological failure of antiretroviral treatments was high in this population of treatment-naive patients, even among patients receiving combination regimens. Clinical progression rates were, however, low in patients treated with RTI combination therapy and HAART.
Acquired Immunodeficiency Syndrome↗
Why is highly active antiretroviral therapy (HAART) not prescribed or discontinued? Swiss HIV Cohort Study.
In this cross-sectional survey conducted at the end of 1997 among the physicians of participants of the Swiss HIV Cohort Study (SHCS), 1487 of 2154 patients (69.0%) were treated with highly active antiretroviral treatment (HAART) defined as triple therapy with a combination of one or two reverse transcriptase inhibitors, and one or two protease inhibitors; 541 patients (25.1%) had never received such treatment. The physician's perception that the patient would not comply with treatment was one reason for not prescribing HAART to 20% of these patients (110). Physicians indicated that the most common reasons for the patient to refuse HAART were the fear of side effects (18%) and the patient's perception that treatment was too complicated (18%). Among 126 patients (5.8%) no longer receiving HAART, the most common reasons for discontinuing treatment were actual side effects (61%) or the fear of side effects (25%). Overall, 16% of patients did not receive therapy in accord with official Swiss guidelines. Multivariate logistic regression analysis indicated that patients with lower education, active intravenous drug users outside of a drug substitution program, and those who acquired HIV infection through intravenous drug use had a significantly higher risk of inadequate treatment. The physician's judgment of patient adherence and the physician's perception of the patient's fear of side effects are critical for the prescription of HAART. Physicians should address these issues to prevent unilateral withholding of treatment and increase the proportion of patients who may benefit from current antiretroviral therapy.
Anti-HIV Agents↗
Discontinuation of primary prophylaxis against Pneumocystis carinii pneumonia in HIV-1-infected adults treated with combination antiretroviral therapy. Swiss HIV Cohort Study.
BACKGROUND: It is unclear whether primary prophylaxis against Pneumocystis carinii pneumonia can be discontinued in patients infected with the human immunodeficiency virus (HIV) who are successfully treated with combination antiretroviral therapy. We prospectively studied the safety of stopping prophylaxis among patients in the Swiss HIV Cohort Study. METHODS: Patients were eligible for our study if their CD4 counts had increased to at least 200 cells per cubic millimeter and 14 percent of total lymphocytes while they were receiving combination antiretroviral therapy, with these levels sustained for at least 12 weeks. Prophylaxis was stopped at study entry, and patients were examined every three months thereafter. The development of P. carinii pneumonia was the primary end point, and the development of toxoplasmic encephalitis the secondary end point. RESULTS: Of the 262 patients included in our analysis, 121 (46.2 percent) were positive for IgG antibodies to Toxoplasma gondii at base line. The median CD4 count at study entry was 325 per cubic millimeter (range, 210 to 806); the median nadir CD4 count was 110 per cubic millimeter (range, 0 to 240). During a median follow-up of 11.3 months (range, 3.0 to 18.8), prophylaxis was resumed in nine patients, and two patients died. There were no cases of P. carinii pneumonia or toxoplasmic encephalitis. The one-sided upper 99 percent confidence limit for the incidence of P. carinii pneumonia was 1.9 cases per 100 patient-years (based on 238 patient-years of follow-up). The corresponding figure for toxoplasmic encephalitis was 4.2 per 100 patient-years (based on 110 patient-years of follow-up). CONCLUSIONS: Stopping primary prophylaxis against P. carinii pneumonia appears to be safe in HIV-infected patients who are receiving combination antiretroviral treatment and who have had a sustained increase in their CD4 counts to at least 200 cells per cubic millimeter and to at least 14 percent of total lymphocytes.
AIDS-Related Opportunistic Infections↗
Poverty and prognosis of HIV infection in Switzerland. Swiss HIV Cohort Study.
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Cohort Studies↗
Impact of antiretroviral combination therapies on AIDS surveillance reports in Switzerland. Swiss HIV Cohort Study.
BACKGROUND: AIDS reporting in Switzerland is mandatory by law. For the first time since the beginning of the epidemic, health authorities observed a decline in AIDS surveillance reports, from 545 new cases in 1995 to 459 in 1996, a decrease of 86 cases. OBJECTIVE: To examine the extent to which this decline in AIDS surveillance reports is attributable to the introduction of antiretroviral combination therapy. PATIENTS AND SETTING: Swiss HIV Cohort Study, a multicentre cohort of adult HIV-infected patients with national coverage. Participants at risk of developing a first AIDS-defining event, defined as persons with a CD4 cell count below 200 x 10(6)/l or in clinical stage B, were studied. METHODS: A parametric statistical survival model was used to estimate the number of AIDS cases expected in the absence of combination therapies. Taking reporting delays into account, the effect of the introduction of combination therapies in the cohort on national AIDS reports was estimated from the difference between the number of expected and observed cases. RESULTS: A total of 4915 participants contributed 10755 person-years and 2366 initial AIDS events. Between 1990 and 1994, about 35% received antiretroviral therapy, predominantly monotherapy. In 1995 and 1996, the prevalence of antiretroviral therapy increased steadily due to the introduction of dual and triple combinations. The mid-year prevalence of use of combination therapies was 6% in 1994, 13% in 1995, and 48% in 1996. The difference between expected and observed cases per half-year increased from 12 in the first 6 months of 1994 to 69 in the second half of 1996. Taking reporting delays into account, we estimated that 43 (95% confidence interval, 17-69) of the deficit of 86 reports could be attributed to combination therapies. CONCLUSION: The introduction of antiretroviral combination therapies in a single cohort study explained 50% of the decline in national AIDS surveillance reports. Monitoring the use and effectiveness of antiretroviral therapy must become an important component of AIDS surveillance systems.
Acquired Immunodeficiency Syndrome↗
Time trends in the treatment of acute myocardial infarction in Switzerland from 1986 to 1993: do they reflect the advances in scientific evidence from clinical trials?
Three acute coronary care surveys (1986, 1990, and 1993) were conducted in the Swiss region of Vaud-Fribourg on all men aged 25 to 64 years hospitalized for a definite myocardial infarction (218, 224, and 167 cases). Nearly all patients received anticoagulants and nitrates. The proportion of patients treated increased significantly, between 1986 and 1990, for antiplatelet drugs (from 51% to 96%) and thrombolytics (from 9% to 44%) and, between 1990 and 1993, for beta-blockers (from 57% to 78%) and angiotensin-converting enzyme inhibitors (from 26% to 43%). The use of calcium antagonists and antiarrhythmics dropped over time. Coronary arteriography and angioplasty were increasingly performed (53% and 18% in 1993), although progressively postponed in-hospital stay. The observed trends reflect a rapid translation of clinical trials into medical practice. However the use of thrombolytics could be raised further by shortening the hospitalization delay (median: 3 hours in 1993) and door-to-needle time (median: 47 minutes) which remained stable over time.
Adrenergic beta-Antagonists↗
The RCGPs' questionnaire for measuring SHOs' satisfaction with hospital training.
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Attitude to Health↗