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Biomedical subjects

S Nesbitt

Publications and source records attributed to S Nesbitt.

At least 19 recordsLinked to original sources
PubMed2006

Pregnancy outcomes in women with or without placental malaria infection.

OBJECTIVE: To assess delivery outcomes in women with placental malaria who presented at public hospitals in Kisumu, a holoendemic region in western Kenya. METHODS: A cross-sectional study using both histology and molecular biology was conducted with 90 consecutive pregnant women who presented at 3 hospitals during a 2-week period. Data collectors completed standardized questionnaires using each patient's hospital record and physical examination results, and registered birth indices such as weight, head circumference, and weight-head ratio. Malaria infection of the placenta was assessed using a molecular biology approach (for genomic differences among parasite species) as well as histology techniques. Of the 5 histologic classes of placental infection, class 1 corresponds to active infection and class 4 to past infection; class 2 and 3 to active chronic infection; and class 5 to uninfected individuals. Plasmodium species typing was determined by polymerase chain reaction amplification of the parasite's genome. RESULTS: In newborns at term, low birth weight was directly associated with classes 2 and 4 of placental infection (P = 0.053 and P = 0.003, respectively), and differences in birth weight remained significant between the 5 classes (P < 0.001) even after adjusting for parity and mother's age. Plasmodium falciparum was the only detected parasite. CONCLUSIONS: In Kisumu, infection with P. falciparum is an important cause of low birth weight and morbidity when it is associated with histologic classes 2 and 4 of placental infection. Moreover, polymerase chain reaction assays should be supported by ministries of health as an ancillary method of collecting data for malaria control during pregnancy and providing a baseline for future interventions.

Adolescent↗
PubMed2004

Stool viruses among paediatric patients from a Nairobi clinic, Kenya.

OBJECTIVE: To document the clinical presentation and prevalence of stool viruses among children presenting with symptoms of acute gastroenteritis (AGE) at Gertrude's Garden Children's Hospital, Nairobi, Kenya. DESIGN: Retrospective case-control study. SETTING: A private paediatric clinic in Nairobi. RESULTS: Viral antigen was detectable in the stool samples of 21 (rotavirus alone in ten cases, adenovirus alone in seven cases, and both viruses in four cases). Diarrhoea was almost universally present (20/21 cases) and was reported more frequently than in a control group of ten children with clinical acute gastroenteritis whose stools tested negative for viruses. Fever, an elevated total leukocyte count, and neutrophilia were commonly observed in patients with viral gastroenteritis. Eight children with viral AGE were treated with antibiotics and eight children were admitted to hospital. CONCLUSION: A viral etiology can frequently be identified among children in Nairobi with AGE. Fever, an elevated leukocyte count, and neutrophilia were not helpful in differentiating viral from non-viral AGE in this series. Supportive management consisting of outpatient oral rehydration therapy without antibiotic treatment should be considered in the non-toxic child with AGE.

Acute Disease↗
PubMed2002

Heritability of left atrial size in the Tecumseh population.

BACKGROUND: Little is known about the determinants of atrial size, and no study has analyzed whether genetic factors are involved in the pathogenesis of LA enlargement. MATERIALS AND METHODS: We studied the heritability of echocardiographic left atrial size in 290 parents from the Tecumseh Blood Pressure Study and 251 children from the Tecumseh Offspring Study. All data from the parents and children were obtained at the same field office in Tecumseh, USA. Left atrial dimension was determined echocardiographically in accordance with American Society of Echocardiography guidelines with the use of leading-edge-to-leading-edge measurements of the maximal distance between the posterior aortic root wall and the posterior left atrial wall at end systole. RESULTS: For correlation between the left atrial dimensions of the parents and their offspring, several models were generated to adjust the atrial dimensions in both groups for an increasing number of clinical variables. After removing the effect of age, gender, height, weight, skinfold thickness, and systolic blood pressure, parent-child correlation for left atrial size was 0.19 (P = 0.007). Further adjustment for left ventricular mass and for measuring left ventricular diastolic function increased the correlation to 0.25 (P = 0.001). CONCLUSIONS: The present data indicate that heredity can explain a small but definite proportion of the variance in left atrial dimension.

Adolescent↗
PubMed2001

Genetic contribution to the variance in left ventricular mass: the Tecumseh Offspring Study.

OBJECTIVE: To estimate the contribution of heredity to the variance in left ventricular mass (LVM), and to ascertain whether genetic factors may interact with non-genetic factors in promoting LVM growth. SUBJECTS AND SETTING: The study population consisted of 290 healthy parents and 251 healthy children living in Tecumseh, Michigan, USA. MAIN OUTCOME MEASURE: Correlation of parents' LVM with offspring's LVM adjusting for a number of clinical variables. METHODS: LVM in parents and offspring was measured with M-mode echocardiography by the same investigators. RESULTS: Parents unadjusted LVM was unrelated to offspring unadjusted LVM, but after removing the confounding effect of age, sex, anthropometric measurements, systolic blood pressure, plasma insulin and urinary sodium excretion, parent-child correlation for LVM was 0.28 (P = 0.006). The relative contribution of parental-adjusted LVM and of several offspring phenotypic and environmental variables on offspring LVM was evaluated by multivariable regression analysis. When age, gender, anthropometric measurements and systolic blood pressure were accounted for, adjusted LVM of parents explained only 1.6% of the total variance in offspring LVM. However, after inclusion of insulin and urinary sodium in the model heredity explained 7.6% of the total variance in offspring LVM, and its predictive power was second only to that of child's height. Furthermore, an interactive effect of parental LVM with offspring systolic blood pressure was found on child's left ventricular mass. CONCLUSION: Heredity can explain a small, but definite proportion of the variance in LVM. Higher blood pressure favors the phenotypic expression of the genes that regulate LVM growth.

Adolescent↗
PubMed2000

Determinants of left ventricular structure and mass in young subjects with sympathetic over-activity. The Tecumseh Offspring Study.

OBJECTIVE: In this study, we tested the hypothesis that sympathetic over-activity may cause metabolic abnormalities and affect left ventricular (LV) structure and mass early in life. SUBJECTS AND SETTING: The study population consisted of 111 healthy adolescents and young adults living in Tecumseh, Michigan (USA). MAIN OUTCOME MEASURES: Correlations of LV mass and structure with several clinical variables in relation to the activity of the sympathetic nervous system. METHODS: Power spectrum density estimates of heart rate variability were calculated with an auto-regressive method, and subjects were divided by cluster analysis into two groups according to low-frequency and high-frequency components. LV data were obtained by echocardiographic assessment RESULTS: Subjects with signs of sympathetic over-activity (n = 38, group 1) had higher heart rate, blood pressure (BP), waist/hip ratio and cholesterol levels than the rest of the group (n = 73, group 2). In group 1 subjects, insulin emerged as the strongest univariate correlate of interventricular septum and posterior wall thicknesses (P< 0.001 for both) and of LV mass (P= 0.009). These relationships remained significant when body mass index was accounted for. By contrast, the marginal univariate relationship with diastolic BP did not remain significant in multivariate analysis. In group 2 subjects, BP was strongly correlated with LV wall thickness and mass both in univariate (P values from 0.03 to < 0.001) and multivariate analyses, while insulin was not. The interactive effect of sympathetic activity and insulin on echocardiographic data was confirmed by multivariate analyses performed in the subjects grouped together (P values from 0.02 to 0.001 for the sympathetic activity x insulin interaction term). CONCLUSIONS: In young subjects with heightened sympathetic activity and initial metabolic abnormalities, insulin is a strong determinant of LV wall thickness and geometry, while in subjects with normal autonomic nervous system activity, the main determinant of left ventricular size is the haemodynamic load.

Adolescent↗
PubMed1999

Diagnosis and risk stratification of patients with anginal pain and non-diagnostic electrocardiograms.

Patients with acute chest pain suggestive of myocardial ischaemia, and normal or non-diagnostic electrocardiograms, form a difficult subgroup for diagnosis and early risk stratification. We prospectively evaluated the role of troponin T (cTnT), troponin I (cTnI), CKMB mass and myoglobin, in the diagnosis and risk stratification of 214 patients with acute chest pain of < or = 24 h and non-diagnostic or normal ECGs admitted directly to the Cardiac Unit of the Royal Victoria Hospital Belfast from the Mobile Coronary Care Unit or the Accident/Emergency Department. This was a single-centre prospective study, and follow-up (3 months) was complete for all patients. Blood was assessed for quantitative cTnT, cTnI, CKMB mass and myoglobin, and qualitative cTnT on admission and at 12 h. Diagnosis of index event and incidence of new cardiac events (death, non-fatal myocardial infarction, revascularization, or readmission for unstable angina) over 3 months were assessed. Based on standard criteria, myocardial infarction occurred in 37/214 (17%), and unstable angina in 72/214 (34%). At 12 h from admission, cardiac troponins had higher sensitivity for the diagnosis of acute coronary syndromes (myocardial infarction and unstable angina) than conventional markers (cTnI 48%, cTnT 38%, CKMB mass 30% or myoglobin 27%). At 3 months, a new cardiac event had occurred in 42/214 (20%). Significantly higher event rates occurred when any of the biochemical markers was elevated, but the statistical significance was highest for patients with elevated cTnI (p < 0.0001). Whilst gender, history of ischaemic heart disease (IHD), stress test response, cTnT, cTnI, CKMB mass and myoglobin were univariate predictors, cTnI at 12 h and stress test response were the only two independent significant predictors for a subsequent cardiac event at 3 months. Raised cTnI at 12 h after admission had the highest sensitivity for the diagnosis of acute coronary syndromes, and was independently associated with a 2-3 times increased risk of future cardiac events within 3 months among patients with acute chest pain suggestive of myocardial ischaemia but with normal or non-diagnostic ECGs.

Aged↗
PubMed1999

Parental hyperdynamic circulation predicts insulin resistance in offspring: The Tecumseh Offspring Study.

Controversy surrounds the pathogenetic mechanisms of the relationship between hyperdynamic circulation and insulin resistance. Two hundred eight children and young adults (mean age, 17.2+/-3.0 years; range, 11 to 26 years) from the Tecumseh Offspring Study whose parents had been assessed with Doppler echocardiography at the age of 34 years during the previous Tecumseh Blood Pressure Study were considered for this analysis. Offspring data were stratified according to tertiles of parental cardiac index. Parents in the top cardiac index tertile had increased heart rate (P=0.001), stroke volume (P=0.0001), left ventricular fractional shortening (P=0.02), and plasma epinephrine (P=0.02) compared with parents in the other tertiles. Body mass index (BMI) and blood pressure were similar in all groups. Offspring of parents with a high cardiac index had greater BMI (P=0.001), skinfold thickness (P=0.008), and waist/hip ratio (P=0.02), higher diastolic blood pressure (P=0.02) and plasma insulin level (P=0.001), and higher heart rate during Stroop's color test (P=0.02) than offspring of parents with a lower cardiac index. In a multivariate regression analysis, offspring BMI was predicted by parental BMI and cardiac index (P=0.0001 and 0.003, respectively). The mother-child relationship explained most of the cardiac index-BMI association. In summary, parental hyperdynamic circulation was an important predictor of overweight, abnormal fat distribution, increased blood pressure, and hyperinsulinemia in offspring. Our results illustrate the complexity of interaction between a genetic tendency and its phenotypic expression. We speculate that the degree of beta-adrenergic responsiveness may be a major determinant of the phenotypic differences between the parents and offspring found in this study.

Adolescent↗
PubMed1998

Clinical consequences of the autonomic imbalance in hypertension and congestive heart failure.

The reduction of coronary mortality is not as large as one would expect from the observed blood pressure lowering in trials of antihypertensive medications. This is not surprising; hypertension is a complex disease where the high blood pressure is only one of numerous coronary risk factors. Sympathetic overactivity in hypertension, independent of the blood pressure, may be conducive to premature atherosclerosis by inducing insulin resistance and dyslipidemia. Through its trophic effect on blood vessels, sympathetic overactivity potentiates vasoconstriction. This, in turn, accelerates hypertension and the metabolic syndrome. The hypertrophy of small coronary arterioles decreases the coronary reserve and enhances coronary spasms. Tachycardia, which is due to increased sympathetic tone and a decreased parasympathetic tone, favors arrhythmias and sudden death in congestive heart failure and hypertension. Increased hematocrit is frequently found in male patients with hypertension, and high hematocrit is a predictor of coronary heart disease/thrombosis. The increase of hematocrit is in part due to an alpha adrenergic postcapillary venoconstriction. Enhanced sympathetic drive, insulin resistance and dyslipidemia have been demonstrated also in congestive heart failure, but the clinical importance of these findings is not fully understood.

Animals↗
PubMed1997

An unusual pH-independent and metal-ion-independent mechanism for hairpin ribozyme catalysis.

BACKGROUND: Hairpin ribozymes (RNA enzymes) catalyze the same chemical reaction as ribonuclease A and yet RNAs do not usually have functional groups analogous to the catalytically essential histidine and lysine sidechains of protein ribonucleases. Some RNA enzymes appear to recruit metal ions to act as Lewis acids in charge stabilization and metal-bound hydroxide for general base catalysis, but it has been reported that the hairpin ribozyme functions in the presence of metal ion chelators. This led us to investigate whether the hairpin ribozyme exploits a metal-ion-independent catalytic strategy. RESULTS: Substitution of sulfur for nonbridging oxygens of the reactive phosphate of the hairpin ribozyme has small, stereospecific and metal-ion-independent effects on cleavage and ligation mediated by this ribozyme. Cobalt hexammine, an exchange-inert metal complex, supports full hairpin ribozyme activity, and the ribozyme's catalytic rate constants display only a shallow dependence on pH. CONCLUSIONS: Direct metal ion coordination to phosphate oxygens is not essential for hairpin ribozyme catalysis and metal-bound hydroxide does not serve as the general base in this catalysis. Several models might account for the unusual pH and metal ion independence: hairpin cleavage and ligation might be limited by a slow conformational change; a pH-independent or metal-cation-independent chemical step, such as breaking the 5' oxygen-phosphorus bond, might be rate determining; or finally, functional groups within the ribozyme might participate directly in catalytic chemistry. Whichever the case, the hairpin ribozyme appears to employ a unique strategy for RNA catalysis.

Base Sequence↗
PubMed1997

Smoking is associated with higher cardiovascular risk in young women than in men: the Tecumseh Blood Pressure Study.

BACKGROUND: Tobacco smoking is associated with a higher prevalence of atherosclerosis and respiratory disease. OBJECTIVE: To investigate differences between hemodynamic and biochemical findings in smokers and nonsmokers in the two sexes separately in the Tecumseh population. METHODS: We studied 851 subjects. They were divided according to smoking habits into group 1, nonsmokers (258 men and 234 women); and group 2, smokers (185 men and 174 women). RESULTS: Unpaired Student's t-tests and nonparametric tests were performed to determine the between-group P-values. Only hematocrit differed significantly between smokers and nonsmokers in both sexes (43.9 +/- 0.2 and 44.6 +/- 9.3%, P < 0.05 in men; 39.2 +/- 0.3 and 40.3 +/- 0.3%, P = 0.007 in women, respectively in nonsmokers and smokers). Triglycerides (80.6 +/- 3.8 and 99.6 +/- 4.3 mg/dl, P < 0.001), left ventricular mass index (95.4 +/- 1.9 and 100.0 +/- 1.2 g/m2, P = 0.008), and posterior wall thickness (9.5 +/- 0.1 and 9.71 +/- 0.01 mm, P = 0.044) were elevated and high-density lipoproteins were decreased (48.7 +/- 0.8 and 44.5 +/- 0.9 mg/dl, P < 0.01) only in women smokers. After adjustment for home systolic blood pressure and body mass index the differences in women remained significant except for posterior wall thickness. CONCLUSION: Tobacco smoking is deleterious to both sexes but it appears to be particularly harmful to women. Our data can, in part, explain why the relative risk of myocardial infarction is higher in women than it is in men.

Adolescent↗
PubMed1997

Trends in left ventricular function over three years in the Tecumseh Study.

The relationship between blood pressure and left ventricular diastolic function was examined in participants of the Tecumseh Blood Pressure study. When subjects were divided into three blood pressure groups according to blood pressure levels 3 years apart, it was found that subjects who were had sustained "hypertension" at both time points (SH) had a decreased early/late diastolic filling rate (E/A ratio) compared to subjects who were hypertensive at only one of the timepoints (OH) and those who were consistently normotensive (NN) (1.71 +/- 0.02 NN vs 1.55 +/- 0.05 OH, (p < 0.0001) vs 1.56 +/- 0.07 SH, (p < 0.04)). This relative order was maintained when the second estimation of diastolic filling was performed 3 years later, but the E/A ratio had decreased significantly in all groups (1.54 +/- 0.01 NN vs 1.45 +/- 0.03 OH (p < 0.01) vs 1.37 +/- 0.06 SH (p < 0.006)), consistent with an age-related reduction in diastolic filling. Heart rates were significantly higher in the hypertensive groups initially (63.5 NN vs 66.2 OH (p < 0.03) vs SH 67.3 (p < 0.01)) and increased in all groups over time, with the largest increase in the SH group (64.9 +/- 0.04 NN vs 67.8 +/- 1.02 OH (p < 0.0001) vs 70.9 +/- 1.6 SH (p < 0.01)). Stroke volume index changed in all groups over time, with the increase greatest in the NN group and least in the SH groups the reverse of this pattern was seen for changes in heart rate. All subjects gained weight over the 3 years of the study so that these unexpected changes in stroke volume index and heart rate could be a consequence of a weight gain-related increase in the sympathetic tone, although we have no direct evidence that this is the case. Should this be so, the smaller increase in stroke volume in conjunction with the larger increase in the heart rate in the sustained hypertensive group may reflect the effects of mild blood pressure elevation in producing a reduction in left ventricular diastolic function associated with a decrease in the inotropic responsiveness of the heart to enhanced sympathetic tone.

Adolescent↗
PubMed1996

Sympathetic overactivity in hypertension. A moving target.

Considerable progress has been made in our understanding of the role of the nervous system in human hypertension. The evidence for a widespread autonomic abnormality in the early phases of hypertension is overwhelming and excessive sympathetic activity is consistently present in such patients since their childhood. The enhanced sympathetic tone in hypertension is associated with the metabolic syndrome of insulin resistance and dyslipidemia. Multiple mechanisms by which sympathetic overactivity could cause both hypertension and the metabolic syndrome have been documented. Furthermore, the excessive sympathetic tone is conducive to coronary heart disease through its association with high hematocrit values and with excessive platelet aggregability. Surprisingly, the myth that patients with neurogenic hypertension have a benign prognosis continues to persist. Much of the misunderstanding stems from the idea that patients with neurogenic hypertension, commonly called "white coat" or borderline hypertension, do not develop established hypertension. There is no support for such an assessment; in fact, patients with neurogenic hypertension are at a high risk of future accelerated hypertension. Another misunderstanding relates to differences in hemodynamics between neurogenic and established hypertension. It is true that patients with neurogenic hypertension initially show an increase of cardiac output. However, this later evolves into a classic picture of established high resistance hypertension. The hemodynamic transition is secondary to a decrease in cardiac responsiveness and an increase in vascular responsiveness over the course of hypertension. With passage of time, vascular reactivity increases, yet sympathetic tone tends to decrease. This can be explained by the "blood pressure seeking behavior of the central nervous system." In hypertension, the central nervous system appears to seek a higher blood pressure level and, as the vasculature becomes hyperresponsive, less sympathetic tone is needed to maintain the elevated blood pressure. This decrease of sympathetic tone in later phases of hypertension should not be viewed as a normalization, since sympathetic tone in relationship to vascular hyperresponsiveness remains excessive and the central nervous system maintains a crucial role in sustaining high blood pressure in hypertension.

Animals↗
PubMed1994

Mutagenesis of the hairpin ribozyme.

Extensive in vitro mutagenesis studies have been performed on the hairpin ribozyme and substrate in an effort to refine the overall secondary structure of the molecule and provide further insight into what elements are essential for activity. A secondary structure consisting of four helices and five loop regions remains the basic model as originally proposed. Two helices, helix 1 and 2, form between the substrate and ribozyme while helices 3 and 4 are within the ribozyme itself. Our results suggest that helices 3 and 4 are smaller than previously proposed, consisting of four base pairs and three base pairs respectively. Helix 4 can be extended without loss of activity and loop 3 at the closed end of the hairpin model can be varied in sequence with retention of activity. There is an unpaired nucleotide between helices 2 and 3 consisting of a single A base, suggesting the opportunity for flexibility within the tertiary structure at this point. Comparisons are made between the new data and previously published mutagenesis and phylogenetic data. Substrate targeting rules require base pairing between helices 1 and 2 with cleavage (*) occurring in a preferred 5'(g/c/u)n*guc3' sequence of the substrate.

Base Composition↗
PubMed1994

Further studies on the use of oligonucleotide facilitators to increase ribozyme turnover.

We showed previously that the turnover of a hammerhead ribozyme cleaving a substrate RNA could be increased by an oligonucleotide (facilitator) that bound to the substrate continguously with the ribozyme. This phenomenon has been investigated further by varying the temperature and the number of base pairs formed between the ribozyme and substrate. The results support the hypothesis that facilitators act by cooperative binding and are beneficial when the rate of cleavage is limited by the stability of the ribozyme/substrate complex. The facilitator also promotes cleavage at lower concentrations of magnesium.

Base Composition↗
PubMed1993

Biochemical characterization of human osteoclast integrins. Osteoclasts express alpha v beta 3, alpha 2 beta 1, and alpha v beta 1 integrins.

The study of osteoclast integrins has been previously hampered by the lack of a source of large numbers of purified osteoclasts. Osteoclastoma, a human giant cell tumor of bone, supplied a rich source of osteoclasts within a tissue containing many diverse cell types. Osteoclastoma integrin immunostaining confirmed the presence of the integrin alpha v beta 3 complex and the alpha 2 and beta 1 integrin subunits on osteoclasts. However, weak integrin expression, for example with alpha v beta 5, was difficult to interpret. Purification with magnetic beads coated with vitronectin receptor monoclonal antibody (13C2) enabled osteoclast membranes to be isolated with high purity and yield (57%) from osteoclastoma tissue. Positively (osteoclast-enriched) selected membranes were biochemically assessed for integrin expression by immunoprecipitation and visualization by non-radioactive enhanced chemiluminescence. alpha 1, alpha 4, alpha 6, alpha 8, alpha M, alpha X, gpIIb, beta 4, beta 6, and beta 8 integrin chains were undetectable at a sensitivity of 1 ng. alpha 3, alpha 5, alpha L, beta 2, and alpha v beta 5 were found in the negatively selected osteoclastoma tissue but not in the positively purified osteoclast membranes. The presence of alpha v beta 1 and alpha 2 beta 1 dimers was demonstrated biochemically on the immunoisolated osteoclast membranes. Osteoclast alpha v beta 3 isolation by Arg-Gly-Asp (RGD) affinity chromatography for NH2-terminal amino acid sequencing confirmed that the osteoclast vitronectin receptor was identical to that previously characterized on other cell types. In situ hybridization using human alpha v riboprobes in osteoclasts from human and rodent bone further demonstrated the high level and specificity of expression of alpha v vitronectin receptor in osteoclasts.

Amino Acid Sequence↗
PubMed1990

Tracheal insufflation of oxygen at low flow: capabilities and limitations.

Tracheal insufflation of oxygen (TRIO) may provide temporary oxygenation for patients or sustain life in apneic mass casualties when conventional ventilatory techniques are not available or feasible. Logistically, minimum flows of TRIO (Vmin) are desirable for field use and to reduce barotrauma should airway obstruction occur. We carried out a feasibility study to determine the efficacy of Vmin of TRIO delivered within 1 cm of the carina, in nine anesthetized and paralyzed dogs. Minimum flows of TRIO for these dogs of average weight (12 kg) was 91 mL/min. In six of the dogs Vmin TRIO was continued and provided oxygenation for an average of 1.5 h compatible with subsequent resuscitation with conventional ventilation. However, PaCO2 levels increased to mean values of 256 mm Hg in the 90 min. To determine what the effect of increased gas mixing was on gas exchange, we repeated Vmin TRIO for 10 min in six of the dogs with and without high frequency oscillations superimposed on the TRIO flow. The oscillations (60 mL at 16.3 Hz) increased carbon dioxide excretion but significantly impaired oxygenation. In completely apneic animals, TRIO at low flow delivered by cricothyroidotomy may be useful as an emergency procedure when upper airway obstruction limits the use of other airway management techniques. However, enhancement of gas mixing during low-flow TRIO impairs oxygenation, so that higher flows would be required when respiratory efforts occur.

Animals↗
PubMed1989

Cost-effectiveness of outpatient parenteral antibiotics: a review of the literature.

The results of studies completed on parenteral antibiotic therapy administered in an outpatient setting are reviewed. Although they varied in both size and sophistication, the studies all found that when patients and their families were carefully screened, outpatient therapy was a cost-effective, safe method of administering intravenous antibiotics. The methods used to compare the costs of inpatient and outpatient intravenous antibiotic therapy varied widely. Only direct costs were included in the early comparisons of inpatient and outpatient therapy, whereas the more recent studies included both direct and indirect costs and benefits. All studies found cost savings in the outpatient setting. Unfortunately, very few elderly patients were included because of a Medicare requirement that intravenous antibiotic therapy be administered or supervised by a physician. However, beginning in 1990, the Medicare Catastrophic Coverage Act of 1988 will cover intravenous drugs administered at home. Thus, it will be possible to study applicability of this therapy for the elderly population.

Anti-Bacterial Agents↗