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R Darioli

Publications and source records attributed to R Darioli.

At least 37 records · Page 2Linked to original sources
PubMed1999

Dose-dependent inverse relationship between alcohol consumption and serum Lp(a) levels in black African males.

Serum or plasma levels of Lp(a) vary widely between individuals and are higher in Africans and their descendants compared with white persons. In whites, high serum levels of Lp(a) are associated with the premature development of atherosclerosis. In both ethnic groups, serum Lp(a) levels are highly genetically determined and only a few environmental or physiological factors, like testosterone or estrogen, have been shown to lower serum Lp(a) levels. In whites, alcohol consumption is associated with lower serum Lp(a) levels. However, the mechanism underlying this association and whether it holds true for blacks is not known. To address these questions, we analyzed serum Lp(a) levels in 333 middle-aged males of African descent from the Seychelles Islands (Indian Ocean). In addition, we analyzed the size of the apo(a) isoforms and the serum levels of albumin and sex hormones in a subset of 279 subjects. Serum Lp(a) levels were similar in teetotalers (median, 32.5 mg/dL; n=42) and occasional drinkers (median, 34.1 mg/dL; n=112). In contrast, individuals consuming 10 to 80 g of ethanol/d (n=83) and heavy drinkers (>80 g of ethanol/d, n=96) had a 9% and 32% lower median Lp(a) level than teetotalers, respectively (P=0.01). The size distribution of the apo(a) isoforms and the mean serum levels of albumin, estradiol, and luteinizing hormone were similar in teetotalers and occasional drinkers compared with moderate and heavy drinkers. These latter 2 groups had lower serum levels of testosterone and sex hormone-binding globulin. These data indicate that alcohol intake is associated in a dose-dependent manner with lower serum Lp(a) levels in males of African descent and that this association is not related to the size of the apo(a) isoforms, to the synthetic function of the liver, or to sex hormone biochemical status.

Adult↗
PubMed1999

Electronic monitoring of compliance to lipid-lowering therapy in clinical practice.

Nonadherence to treatment is a common problem in the clinical management of hypercholesterolemic patients. This study was carried out with the aim of monitoring the daily compliance to a 6-month course of lipid-lowering therapy, using a microelectronic device, the Medication Event Monitoring System (MEMS), versus pill count. Forty men with primary hypercholesterolemia were prescribed fluvastatin 1 x 40 mg daily, provided in a MEMS package to record the date and time of each opening of the pillbox. Thirty-nine of 40 patients (98%) completed the study. Total cholesterol and LDL cholesterol levels decreased significantly (18% and 25%, p < 0.001) during the 6-month therapy period. A high mean rate of compliance was achieved by MEMS using the following three indexes--compliance to total prescribed dose (88.8% +/- 13.5%), compliance to prescribed days (82.4% +/- 19.5%), and compliance to prescribed time of day (81.86% +/- 19.5%)--and by pill count (93.4% +/- 9.5%). In addition, the MEMS provided some patterns of nonadherence to medication, undetectable by pill count alone, such as a drug holiday in 38% of cases, a drug omission for more than 7 consecutive days in 9% of cases, and, conversely, use of more than the one prescribed daily dose in 47% of cases. A significant correlation between the rate of compliance and the decrease in LDL cholesterol was observed only when the compliance was assessed by MEMS. The results indicate that MEMS is a useful tool for monitoring compliance in clinical practice and may possibly increase adherence to long-term lipid-lowering therapy.

Adult↗
PubMed1998

[Comparative immunogenicity of 2 antirabies vaccines in a 2-1-1 post-exposure vaccination schedule].

Few trials have compared the Purified Duck Embryo Vaccine (PDEV) and the Human Diploid Cell Vaccine (HDCV) in a post-exposure immunization schedule of 4 shots (2 on day 0 and 1 each on day 7 and 21, or 2-1-1 schedule). A retrospective analysis compared 10 patients with PEDV and 20 with HDCV, who had received the 2-1-1 schedule as well as 20 UI mg/kg of immune globulins on day 0. The median neutralizing antibody titers on day 21 (after 3 doses) and the median of maximum titers until day 90 were higher for HDCV than for PEDV (0.6 IU/ml versus 3.5 IU/ml [p < 0.04] and 2.5 IU/ml versus 5.8 IU/ml [p < 0.03] respectively). Seven patients had not reached the seroconversion titer of 0.5 IU/ml after 3 doses (day 21). These results differ from previous studies showing a 100% seroconversion rate on day 21, and suggest that more studies are required before these 2 vaccines can be used in the 2-1-1 schedule after severe exposure.

Adult↗
PubMed1998

[The value of screening serology in anti-hepatitis A vaccination of travelers].

UNLABELLED: To select the travellers most likely to benefit from anti-hepatitis A (HA) antibody testing, the following criteria have been proposed: (A) being born before 1945, (B) a stay over 1 year in a developing country or (C) a history of jaundice. We present a prospective study to assess the practical use of these criteria. Following a recent survey in the general population of Lausanne showing HA seroprevalence of 52.6% in the age group over 45, we included an A1 criterion (A extended to birth before 1950). Anti-HA IgG testing and a questionnaire were proposed to all travellers presenting one or more criteria. RESULTS: Out of 1187 consecutive travellers, 176 (14.8%) had one or more criteria (219 [18.5%] when A1 was used). Criteria A applied to 8.5% of all travellers, A1 to 13.8%, B to 6.3% and C to 3.1%. Only 3% of travellers had more than one criterion. Overall seroprevalence among the selected group was 48.3%. Seroprevalence of travellers below 60 years old was under 30%, unless a second criterion was present in which case seroprevalence was 10% higher. Eighty percent of travellers with a history of jaundice were found to be positive. The use of the recommended criteria spared 94 travellers (46.3% of those tested and 7.9% of all travellers) unnecessary immunisation. Among travellers older than 60 years, a 30% economy on the total sum for immunising all of them, without any prior testing was realised. CONCLUSIONS: Among the population of travelers consulting our travel clinic, the seroprevalence for HA is lower than in the general population. We recommend that testing should be proposed only to travellers aged over 60, or with a history of jaundice, or to those with a combination of 2 out of 3 criteria.

Adult↗
PubMed1998

Apolipoprotein E polymorphism and the distribution profile of very low density lipoproteins; an influence of the E4 allele on large (Sf > 60) particles.

Very low density lipoprotein (VLDL) distribution and composition have been examined as a function of apo E genotype (E2/2 + E2/3 vs. E3/3 vs. E3/4 + E4/4) in healthy, normolipaemic subjects. Apo E genotype had a marked impact on plasma concentrations of apo E rich VLDL, but no influence on concentrations of apo E free particles. Thus, there was a trend to lower concentrations of apo E rich total VLDL in apo E4 carriers (mg/dl; E2, 49.1 +/- 35.2; E3, 52.5 +/- 30.9; E4 35.2 +/- 22.3; ANOVA P = 0.16; when comparing E4 with E2 + E3, P = 0.06). Consequently, there were highly significant differences between apo E-defined subgroups in terms of the percentage distribution of bound and non-bound fractions (% total VLDL non-bound to apo E: E2, 44.0 +/- 12.7%; E3, 39.7 +/- 8.7%; E4 51.0 +/- 12.2%; ANOVA P = 0.007). Subfractionation of VLDL into density subclasses revealed that genotype differences were restricted to large VLDL (Sf > 60). Significantly lower concentrations of apo E-rich particles were observed in E4 carriers for VLDL-1 Sf 400-100 (ANOVA P = 0.004) and VLDL-2 (P = 0.009) but not for small VLDL-3 Sf 60-20 (P = 0.34). No differences in plasma concentrations of apo E free VLDL were observed between genotype subclasses across the density spectrum. Compositional differences between the apo E defined VLDL were also evident for the core lipids. Apo E containing VLDL was enriched in esterified cholesterol and depleted in triglycerides compared to apo E poor VLDL: the difference became more marked with increasing density of the particles. Lipoprotein composition was not modulated to any great extent by apo E genotype. In patients with familial hypercholesterolaemia, relative concentrations of apo E rich, large VLDL were significantly higher than in controls. Treatment lowered concentrations of both apo E rich and apo E free VLDL but led to a greater relative enrichment of large VLDL in apo E containing particles. Apo E polymorphism appears to influence plasma concentrations of VLDL particles. The data are consistent with more pronounced receptor-mediated elimination of apo E4 containing VLDL. This may be a contributory factor to the down regulation of receptor activity which is suggested to be of major importance in provoking higher cholesterol levels associated with the apo E4 isoform.

Adult↗
PubMed1996

Effects of repeated annual influenza vaccination on vaccine sero-response in young and elderly adults.

Three cohort studies in adults were performed during the period from 1986 to 1989. Eight hundred and eighty-four subjects were, one or more times, immunized with influenza vaccines, and pre- and post-vaccination antibody titres were determined by hemagglutination inhibition tests. One thousand and one hundred and nineteen vaccination events in 681 subjects could be analysed by a comparison, per trial and per influenza (sub)type, between groups with and without influenza vaccination in previous years. Effect size, odds ratio and protection rate difference, were used as effect measures. Subjects with previous vaccination showed higher pre-vaccination antibody than those without. The average change of the post-vaccination proportion of subjects with high antibody titre value to previous vaccination, was +9.4% (95% CI: +5.3 to 13.6%) for A-H3N2 vaccine components, -2.1% (-8.1 to 3.9%, not significant) for A-H1N1 and -10.6% (-16.5% to -4.8%) for B. In a linear regression model, pre-vaccination titres and the status of previous vaccination were identified as factors significantly influencing post-vaccination titres. These findings are discussed in the context of a short review of the literature. It is concluded that the status of previous vaccination should always be addressed as an independent factor in serological vaccination studies.

Adult↗
PubMed1995

[Occupational activities and allergic respiratory manifestations].

The authors review aspects of occupational asthma that are important for the practitioner. Insurance problems are dealt with in the light of local regulations. Detailed chapters are devoted to baker's asthma (various aeroallergens), to plastic workers and painters (isocyanates) and to respiratory diseases among farmers. Finally, a list of other occupations in which asthma typically occurs is given. The responsibility of practitioners in charge of young patients about to choose their future profession is underlined.

Agricultural Workers' Diseases↗
PubMed1995

Postischemic blood flow response in hypercholesterolemic patients.

We undertook this cross-sectional study to compare the mechanical behavior and postischemic response of the radial artery of 15 newly diagnosed hypercholesterolemic patients with those of 15 age- and sex-matched normocholesterolemic control subjects and 21 hypercholesterolemic patients treated for 2 years with an 3-hydroxy-3-methylglutaryl coenzyme A reductase inhibitor (simvastatin, 10 to 20 mg/d). At the time of the study total cholesterol levels were at 7.9 +/- 0.2, 4.9 +/- 0.2, and 6.0 +/- 0.3 mmol/L in the three groups, respectively (mean +/- SEM, P < .001). High-resolution, noninvasive echotracking for assessment of internal arterial diameter was combined with measurements of blood flow velocity by Doppler and blood pressure by photoplethysmography. Radial cross-sectional compliance and distensibility were similar in all groups. Forearm blood flow and flow-mediated dilation were measured after a 5-minute upper arm occlusion. Flow was calculated from the vessel diameter and blood flow velocity recorded simultaneously at the same site. Flow-mediated dilation after ischemia was not significantly different among the three groups. However, forearm blood flow increase was markedly blunted (P < .01) in untreated hypercholesterolemic patients (211%) compared with the normocholesterolemic control subjects (411%) and treated patients (365%). These findings suggest that the distensibility of the radial artery, a muscular conduit vessel usually devoid of atherosclerotic lesions, and its flow-mediated dilation are preserved in hypercholesterolemic patients. In contrast, forearm resistance vessels exhibit a markedly reduced postischemic blood flow response that may be restored by prolonged lipid-lowering intervention.

Adult↗
PubMed1995

Combined treatment with captopril, hydrochlorothiazide and pravastatin in dyslipidemic hypertensive patients.

OBJECTIVES: Hypertension and hypercholesterolemia frequently coexist, necessitating concurrent treatments for both disorders. The present study aimed at evaluating the efficacy, the safety, and the toleration of captopril, an ACE inhibitor, hydrochlorothiazide, a diuretic, and pravastatin, a HMG-CoA reductase inhibitor co-administered in hypertensive patients in general practice. DESIGN: The patients were followed for 16 weeks and asked to comply with a lipid lowering diet for the whole period. Captopril, 50 mg/once daily, was administered alone for the first 4 weeks. Hydrochlorothiazide, 25 mg/day, was added after 4 weeks if required. Pravastatin treatment (20 mg/day) was started at the 8th week of the study and its dose was doubled 4 weeks later if needed. PATIENTS: A total of 603 patients with hypertension (diastolic blood pressure > or = 95 mmHg) and dyslipidemia (total cholesterol > 6.5 mmol/l) were included. SETTING: The study was performed in general practice by 230 physicians. MAIN OUTCOME MEASURE: Determination of blood pressure, circulating levels of total cholesterol, HDL-cholesterol and triglycerides, and blood chemistry for safety monitoring. RESULTS: At the end of the trial 75.1% of patients had their diastolic blood pressure < or = 90 mmHg and 43.5% a total cholesterol level < 6.5 mmol/l. The overall incidence of adverse events was 21.7%, leading to withdrawal in 10.9% of the total number of patients. The combined treatments had no deleterious effect on safety variables. CONCLUSIONS: Captopril, hydrochlorothiazide and pravastatin are effective and well tolerated medications to treat dyslipidemic hypertensive patients.

Adult↗
PubMed1994

Comparison of serum lipoprotein(a) distribution and its correlates among black and white populations.

BACKGROUND: Epidemiological data on serum lipoprotein(a) (Lp(a)), a presumably strong risk factor for coronary artery disease in White populations, has mostly been derived, in Black populations, from small samples. This study compares the distribution and the determinants of serum Lp(a) in Blacks and in Whites using large representative samples and the same methods in both populations. METHODS: The distribution and the correlates of serum Lp(a) were investigated in population-based samples of 701 Blacks in the Seychelles and 634 Whites in Switzerland, aged 25-64 years. Serum Lp(a) was quantified using a commercial immunoradiometric assay. RESULTS: The distribution of serum Lp(a) was similarly skewed in both ethnic groups, but median Lp(a) concentration was about twofold higher in Blacks (210 mg/l) compared to Whites (100 mg/l). The proportions of individuals with elevated serum Lp(a) (> 300 mg/l) was about 50% higher in Blacks (37.5%) than in Whites (25.2%). In both ethnic groups, serum Lp(a) was found to correlate with total cholesterol, LDL-cholesterol and apoprotein B but not with HDL-cholesterol, alcohol intake, smoking, and body mass index. The variance in serum Lp(a) concentration explained by any combination of these factors was smaller than 5.3% in the two populations. CONCLUSIONS: The measured factors did not explain the higher levels of serum Lp(a) found in Blacks compared to Whites. These findings are consistent with the hypothesis that genetic factors account for much of the variation of serum Lp(a) in both populations.

Adult↗
PubMed1994

[Prevention for travel to the tropics].

The Swiss Working Group for Health Advice to Travellers regularly publishes its recommendations for malaria prophylaxis and vaccination as supplement to the 'Bulletin' of the Federal Office of Public Health. In this review the strategy with respect to information, to clever behavior abroad, to chemoprophylaxis and immunization prophylaxis is analyzed. A critical evaluation of emergency self-therapy describes remaining questions in particular.

Antimalarials↗
PubMed1993

[Association between lipoprotein(a) and coronary disease].

The relationship of serum lipoprotein(a) [Lp(a)] to ischemic heart disease was investigated in a series of 114 men undergoing elective diagnostic coronary angiography at the University Hospital of Lausanne (Switzerland). Serum Lp(a) was higher (median: 134 mg/l; mean +/- SD: 371 +/- 509 mg/l) in the 76 individuals with ischemic heart disease, as defined by at least one significant stenosis (> or = 50%) in a proximal segment of a major coronary artery, compared to the 38 individuals without significant stenosis (60 mg/l; 155 +/- 218 mg/l). The risk ratio for ischemic heart disease was 4.2 (95% CI: 1.05-16.6) for serum Lp(a) greater than 300 mg/l compared to concentrations smaller than 50 mg/l, after adjustment for total cholesterol, HDL-cholesterol, body mass index, cigarette smoking, hypertension, and age. Lp(a) was the strongest lipid correlate of a severity score for coronary atherosclerosis (Jenkins' score) after adjustment for the other considered risk factors (partial R squared = 0.10; p < 0.001). These data are consistent with a strong independent effect of Lp(a) on ischemic heart disease. The literature on Lp(a) is reviewed and a clinical approach proposed.

Body Mass Index↗
PubMed1993

Simultaneous active and passive immunization against hepatitis A studied in a population of travellers.

Three hundred travellers, seronegative for hepatitis A, were enrolled into this study to evaluate a new inactivated hepatitis A vaccine. Three injections, each containing at least 720 ELISA units, were administered intramuscularly at months 0, 1 and 6. The subjects were distributed into three groups: 100 received vaccine only; 100 received a single injection of immunoglobulin enriched in HAV antibody; and the 100 remaining travellers received the vaccine and immunoglobulin administered simultaneously with the first vaccine dose. In both vaccinated groups, the rate of seroconversion was found to be higher than 90% at month 1, reaching 100% and 97.8% at month 2 in groups 1 and 3, respectively, and 100% at month 7. In the group receiving both vaccine and immunoglobulin, antibody production was somewhat slower and the final titres were, on average, slightly lower than those obtained in the group with the vaccine alone (GMT 2488 and 3614 mIU ml-1 respectively; p = 0.02). The vaccine appeared to be highly immunogenic in all subjects and was also well tolerated. The slight inhibition of antibody production, induced by the concurrent administration of immunoglobulin, does not affect the overall protection afforded by the vaccine. We conclude that simultaneous active and passive hepatitis A immunizations can be recommended.

Adolescent↗
PubMed1992

[Screening for cardiovascular disease risk factors among employees of a hospital].

A health promotion and screening program for the detection of the major risk factors for ischemic heart disease was carried out in 1990 among the employees (n = 4,521; 70% female) of the Centre Hospitalier Universitaire Vaudois (CHUV). The prevalence of risk factors among the 1,425 employees (73% female) who took part in the study (participation rate: males 29%, females 33%) was compared with the prevalence of risk factors within three other populations: 1) new CHUV employees, who are systematically screened (n = 424: 71% female); 2) a representative sample of the general population; and 3) a group of employees from 44 companies located in the same region. Smoking was the most common of the three main risk factors; its prevalence was lowest among CHUV employees and highest among employees of the 44 firms. The prevalence of hypercholesterolemia and high blood pressure was variable among the different populations. These variations could partly be due to differences in methodologies and measurement conditions, but could not totally be explained in this way.

Adult↗
PubMed1991

Effect of weight reduction in moderately overweight patients on recorded ambulatory blood pressure and free cytosolic platelet calcium.

Although platelet cytosolic calcium has been shown to decrease during pharmacological treatment of hypertension, there is no evidence that cytosolic calcium also falls during a nonpharmacological reduction in blood pressure. To provide such evidence, we examined prospectively the relation between platelet cytosolic calcium and ambulatory blood pressure during weight reduction in moderately overweight (body mass index [BMI] greater than 25), mildly hypertensive individuals. The experimental group (responders: BMI reduction greater than 5%) consisted of 19 patients who lost 8.5 +/- 2.9 kg (mean +/- SD, p less than 0.05) during a 10-week hypocaloric diet, whereas the control group (nonresponders: BMI reduction less than 5%) consisted of 12 patients who showed no relevant change in body weight (-2.0 +/- 1.3 kg) during the same period of time. The moderate weight loss of the responders decreased blood pressure by 14/5 mm Hg (p less than 0.05), as measured by ambulatory monitoring, which renders a placebo effect unlikely. This nonpharmacological reduction in blood pressure was accompanied by a proportional 11% decrease (p less than 0.05) in platelet cytosolic calcium and also by significant (p less than 0.05) decreases in plasma catecholamines and serum cholesterol. These findings establish the concept of a nonpharmacological reduction in free cytosolic platelet calcium in humans and add further evidence suggesting a link between intracellular calcium homeostasis and blood pressure regulation.

Blood Platelets↗