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At least 991 records · Page 55Linked to original sources
PubMed1992

[Should hypercholesterolemic women be treated?].

There have been few studies designed to evaluate the problem of hypercholesterolaemia in women despite the fact that, like men, cardiovascular disease is their main cause of death. Serum cholesterol is a risk factor in women, but the increased risk appears at much higher values of serum cholesterol than observed in men. In women, low HDL-cholesterol seems to be the best predictive factor for the occurrence of a coronary event, especially if the triglycerides are raised. The absence of therapeutic data on the treatment of hypercholesterolaemia in women underlines the need for a specific trial to assess the effects of lipid-lowering drugs in this population. The cardiovascular benefits of hormone substitute therapy at the menopause have been reported in several studies and a large scale randomised trial is under way to confirm these results. The benefit of hypercholesterolaemic therapy in women with mild hypercholesterolaemia has not been proved. When the serum cholesterol level is over 3 g/l (7.77 mmol/l), early treatment is advisable.

Adult↗
PubMed1992

Reversibility of left ventricular hypertrophy.

Left ventricular hypertrophy (LVH) is a powerful independent risk factor for coronary artery disease. This overview of 104 studies examines the ability of various types of antihypertensive therapies to reverse LVH as assessed by echocardiography. Combination therapy, angiotensin converting enzyme (ACE) inhibitors, and methyldopa were the most effective in reversing LV mass; vasodilators such as minoxidil and hydralazine had no effect on LVH. These differences were independent of the degree of fall in blood pressure and duration of therapy. beta-blockers were as effective as ACE inhibitors in decreasing LV wall thickness. Possible reasons for drug differences in reversing LVH are discussed. Preliminary evidence suggests that reversing LVH by antihypertensive drug therapy is associated with a reduction in cardiovascular complications.

Antihypertensive Agents↗
PubMed1992

Cholesterol reduction in single and multifactor randomized trials: relationship to CHD incidence and total mortality as found by meta analysis of twenty-two trials.

This paper reports on a meta analysis in twenty-two randomized both single and multifactor trials regarding the effect of designed cholesterol reduction on total mortality and CHD incidence. Per cent reduction in CHD incidence was 2.5 for every per cent associated net reduction in total cholesterol, but was only 0.74% for total mortality. Since total net reduction in cholesterol was about 5% in all trials combined, the number of participants was far too small to demonstrate a significant expected reduction of 4% in total mortality. However, the 4% reduction lies just outside the observed 95% confidence limits of the overall estimate of effect on total mortality (OR = 1.02; CL 0.97, 1.07). It is concluded that cholesterol reduction must be much larger than 5% to be able to reduce the relative risk of CHD substantially and total mortality moderately.

Cholesterol↗
PubMed1992

Efficacy of tianeptine in comparative trials versus reference antidepressants. An overview.

The clinical properties of tianeptine have been assessed in double-blind controlled studies, which involved depressed patients fulfilling DSM-III criteria for either major depression--single episode or recurrent (without melancholia and psychotic features)--or dysthymic disorder--with or without an additional diagnosis of alcohol abuse or dependence. Five studies have compared tianeptine with reference antidepressants: its efficacy has been found to be similar to that of amitriptyline in depressed out-patients. However, these data need to be confirmed by other controlled trials v. reference drugs and by at least two placebo-controlled studies. Tianeptine does not induce sleep disorders, anticholinergic effects, or modifications of cardiovascular variables or biological parameters (renal, haematological, or hepatic). After the end of treatment, the only signs of withdrawal have been some disturbances of sleep.

Amitriptyline↗
PubMed1992

A quantitative assessment of oral contraceptive use and risk of ovarian cancer.

OBJECTIVE: To provide a quantitative assessment of the association between oral contraceptive (OC) use and ovarian cancer using results from the published literature. DATA SOURCES: We conducted a MEDLINE literature search for all epidemiologic studies of OC and ovarian cancer published in English between 1970-1991. The reference list for each article was reviewed to locate additional published articles. METHODS OF STUDY SELECTION: We included 20 studies in which a relative risk and either a standard error, confidence interval, or P value was reported, or sufficient data were presented to allow us to calculate these measures. DATA EXTRACTION AND SYNTHESIS: We summarized the findings using weighted averages and regression analyses. We found a summary relative risk of 0.64 (95% confidence interval 0.57-0.73) associated with ever-use of OC, indicating a 36% reduction in ovarian cancer risk. The risk of ovarian cancer decreased with increasing duration of OC use; we noted a 10-12% decrease in risk with 1 year of use and approximately a 50% decrease after 5 years of use. The reduced risk was present among both nulliparous and parous women and it appeared to last for at least 10 years after cessation of use. Although most studies assessed the use of cessation of use. Although most studies assessed the use of OC formulations from the 1960s and 1970s, data from the Cancer and Steroid Hormone Study indicate that the decreased ovarian cancer risk may also be present with current lower-dose formulations. CONCLUSION: The protective effect of OC against ovarian cancer risk should be considered in a woman's decision to use OC.

Contraceptives, Oral↗
PubMed1992

The business of preventing African-American infant mortality.

African-American women are twice as likely as women from other ethnic groups to have babies with low birth weights and to experience the loss of infant death. The problem is so endemic in black communities in Alameda County, California, that numerous programs have been developed over the past decade to reduce maternal risk factors and eliminate barriers to prenatal care. Despite these efforts, African-American ethnicity continues to be a major risk factor for infant mortality for reasons that are poorly understood. We take a critical look at 3 types of studies characteristic of infant mortality research: epidemiologic, studies that advocate prenatal care, and ethnomedical (cultural). We argue that the assumptions informing this research restrict the thinking about infant mortality and the political issues involved in how prevention programs are developed and structured. The persistent focus on maternal behavioral characteristics limits more in-depth analysis of the micropolitics of perinatal bureaucracies established in response to this ongoing crisis.

Black or African American↗
PubMed1992

Chemicals classified by IARC: their potency in tests for carcinogenicity in rodents and their genotoxicity and acute toxicity.

Chemicals classified by the IARC to its groups 1, 2A, 2B and 3 were examined in an attempt to identify characteristics of their behaviour in experimental studies of carcinogenicity, genotoxicity and acute mammalian toxicity that correlate with those categories. Only those agents for which information on carcinogenic potency was available were studied. In both mice and rats, more chemicals were potent carcinogens if they had been categorized in Group 1 (human carcinogens) than if they had been put into one of the other categories. Not surprisingly, there was a weak association between carcinogenic potency and acute toxicity. Mice were especially sensitive to tumour induction by halides; the lower sensitivity of rats to any carcinogenic effect of halides could be due in part to their higher systemic toxicity in this species: a reduced differential of toxic and carcinogenic doses decreases the dose window in which carcinogenic effects may be demonstrated. It was notable that the human carcinogens were active in those genotoxicity tests with higher specificity for identifying rodent carcinogens. Predictive assays for carcinogenicity that were considered to be highly specific were tests for cytogenetic effects in vivo, unscheduled DNA synthesis in hepatocytes, mutation in any of the five commonly used strains of Salmonella typhimurium and mutation at the hprt locus in mammalian cells. None of the relationships was strong enough to form the basis of a simple categorization, but they could serve to alert investigators to chemicals of special toxicological interest and importance.

Animals↗
PubMed1992

Chemical toxicity and chemical carcinogenesis. Is there a causal connection? A comparative morphological evaluation of 1500 experiments.

Chemicals cause toxic and carcinogenic effects as well as beneficial and other adverse effects in animals and in humans. The purpose of this paper is to assess whether there is a direct, uniform causal relationship between toxicity and carcinogenicity. Within this context, specific issues receive attention: the influence of exposure concentrations on carcinogenesis; kidney cancer and alpha 2 mu-globulin; urinary calculi and tumours; and cell turnover or proliferation and cancer. The data used to evaluate histopathological site-specific correspondence between these two end-points comes from 130 studies of chemical carcinogenesis designed and conducted by the US National Toxicology Program (NTP). Nearly 1500 sex-species-exposure group experiments were evaluated for morphological evidence of toxicity and/or carcinogenicity, for dose-response relationships, and for site-specific correlations of toxicity and carcinogenicity. The major conclusions are that chemicals evaluated for long-term toxicity and carcinogenicity in experimental animals can be divided into three categories: (1) those that cause organ toxicity without cancer, (2) those that cause site-specific cancer with no associated toxicity and (3) those that cause toxicity and cancer in the same organ. Examples are given to illustrate each category. On the basis of this comparative analysis, in the great majority of cases the available data do not support a correlation between chemically induced toxicity and carcinogenicity. Moreover, until considerably more scientific knowledge about molecular mechanisms of carcinogenesis becomes available and accepted, attempts to use findings on toxicity to modify the risk assessment process will be fraught with uncertainty and might even have a negative impact on public health.

Animals↗
PubMed1992

Overall safety of Arthrotec.

Data from four double-blind studies of the treatment of patients with rheumatoid arthritis or osteoarthritis were combined. For 4 to 12 weeks, 747 patients received Arthrotec, a combination of 50 mg of diclofenac and 200 micrograms of misoprostol, and 754 patients received 50 mg of diclofenac; the drugs were given twice or three times daily. The five most commonly reported adverse events were abdominal pain by 23.2% of the diclofenac/misoprostol patients and 19.8% of the diclofenac patients; diarrhea by 19.9% and 11.3%; nausea by 11.8% and 6.5%; dyspepsia by 11.2% and 7.8%; and flatulence by 8.0% and 3.1%. Other adverse events, reported by similar proportions of both treatment groups, included headache, gastritis, dizziness, vomiting, and constipation. In the diclofenac/misoprostol-treated patients, the abdominal pain and diarrhea were rated mild in 30.6% and 24.3%, moderate in 49.1% and 51.4%, and severe in 20.2% and 24.3%. Serious adverse events occurred in eight of the diclofenac/misoprostol-treated patients and in 13 of the diclofenac-treated patients; 12.6% and 10.1%, respectively, were withdrawn from the study because of adverse events. Results of laboratory tests of hepatic and renal function were similar in the two treatment groups.

Administration, Oral↗
PubMed1992

Apparent lack of synergism between heparin and dihydroergotamine in prevention of deep vein thrombosis after elective hip replacement: a randomised double-blind trial reported in conjunction with an overview of previous results.

We report the results of a double-blind, randomised trial of venous thrombosis (VT) prevention in 117 patients having elective hip replacement where low dose heparin alone (5,000 IU sodium heparin given subcutaneously [sc] 8 hourly until the seventh postoperative day) was compared with low dose heparin plus dihydroergotamine (DHE; 0.5 mg, given 8 hourly by sc injection). The trial end point consisted of VT discovered through bilateral ascending venography done routinely on the seventh postoperative day. VT developed in 34% of patients given heparin/DHE (95% confidence interval = 22% - 47%) compared with 24% in those given low dose heparin alone (95% confidence interval = 14% - 37%; p = 0.34), difference = 10% (95% confidence interval = -7% to +26%). Corresponding figures for the incidence of proximal (above-knee) thrombosis were 17% and 14% (95% confidence intervals = 8% - 29% and 6% - 25% respectively). These results are discussed in the context of a detailed overview of published evidence concerning VT prevention with heparin/DHE after hip replacement and we conclude it is unlikely that heparin/DHE is markedly superior to low dose heparin alone in this clinical setting.

Aged↗
PubMedDate not supplied

[3 years of "new developments" in pharmacotherapy. An update which is also a proposal for participative experimentation].

The analysis of the contents of key national and international drug bulletins provides a comprehensive overview of what has been produced worldwide in the field of pharmacology and therapeutics over the last few years after the last publication in R d 1). The work presented, tries to avoid the risk of being a purely descriptive listing of true and false "new" information, and may be seen as an "experiment of information transfer": the available data are presented and summarised from various complementary points of view, to suggest also a methodology of permanent education, for which instruments are also proposed. Further, the text is tentatively proposed as an experiment of communication between nurses and pharmacists, to stimulate their dialogue and interaction both with respect to the use of drug literature and to the evaluation of daily needs of information in routine hospital practice.

Drug Therapy↗