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T R Einarson

Publications and source records attributed to T R Einarson.

At least 19 recordsLinked to original sources
PubMed2001

Pharmacotherapies for attention-deficit/hyperactivity disorder: expected-cost analysis.

BACKGROUND: Attention-deficit/hyperactivity disorder (ADHD) is a common childhood neurobehavioral disorder characterized by inattention, hyperactivity, and impulsivity. Prevalence estimates in elementary school children generally range from 3% to 8%. ADHD is frequently treated with psychostimulant medications, which have been shown to improve both cognitive and behavioral outcomes for most children. OBJECTIVE: The goal of this study was to estimate the total expected costs for the treatment and management of school-age children with ADHD using 6 commonly prescribed pharmacotherapies: methylphenidate immediate-release/extended-release (MPH IR/ER), methylphenidate immediate-release (MPH IR), Metadate CD (branded MPH IR/ER), Concerta (branded MPH ER), Ritalin (branded MPH IR), and Adderall (a combination of dextroamphetamine and amphetamine salts). METHODS: A literature review and clinical assessment using a 27-question survey instrument were used to capture information on the clinical characteristics of ADHD, including common treatment regimens, clinical management of patients, pathways of care, and components of care. A meta-analysis provided response rates for 3 commonly used pharmacotherapies: Metadate CD, MPH IR, and Adderall. Information from the clinical assessment and the meta-analysis were used to populate a decision-analytic model to compute total expected cost for each comparator. RESULTS: The average total annual expected cost per patient was $1,487 for Metadate CD, $1,631 for Concerta. $1,792 for MPH IR/ER, $1,845 for MPH IR, $2,080 for Ritalin, and $2,232 for Adderall. CONCLUSIONS: Metadate CD had the lowest total expected cost and Adderall had the highest total expected cost among the ADHD pharmacotherapies evaluated. The differences were attributable to differences in drug-acquisition costs and the need for in-school dosing of twice-daily and thrice-daily medications.

Amphetamines↗
PubMed2001

Evidence based information on drug use during pregnancy: a survey of community pharmacists in three countries.

OBJECTIVE: To evaluate whether community pharmacists provide evidence-based information to women inquiring about specific drug use during pregnancy. DESIGN: A trained female student posing as a surrogate shopper requested information about the relative safety/risks of medications during pregnancy in two scenarios. Forty randomly selected pharmacies were surveyed in the Netherlands, Canada and Iceland, and pharmacists' recommendations were noted. Main outcome measures included the type of information that was provided, its presentation, and the source of information used. RESULTS: A relatively small proportion of pharmacists surveyed, provided evidence-based information regarding the drugs in question. Only 14% referred to current medical literature, while 60% consulted the product monograph. Over 90% of pharmacists referred the client to a physician. CONCLUSIONS: Community pharmacists do not disseminate evidence-based recommendations when counseling women on drug use in pregnancy, and need further education on resources concerning drugs in pregnancy that are currently available.

Adult↗
PubMed2001

The role of acetaldehyde in pregnancy outcome after prenatal alcohol exposure.

It is not known why some heavy-drinking women give birth to children with alcohol-related birth defects (ARBD) whereas others do not. The objective of this study was to determine whether the frequency of elevated maternal blood acetaldehyde levels among alcoholics is in the range of ARBD among alcoholic women. MEDLINE was searched from 1980 to 2000 using the key words acetaldehyde, pharmacokinetics, and alcoholism for controlled trials reporting blood or breath acetaldehyde levels in alcoholics and nonalcoholics. Separately, using the key words fetal alcohol syndrome, epidemiology, prevalence, incidence, and frequency, articles were identified reporting ARBD incidences among the offspring of heavy drinkers. Of 23 articles reporting acetaldehyde levels in alcoholics, four met the inclusion criteria. Forty-three studies reported on the rate of ARBD in heavy drinkers, and 14 were accepted. Thirty-four percent of heavy drinkers had a child with ARBD, and 43% of chronic alcoholics had high acetaldehyde levels. The similar frequencies of high acetaldehyde levels among alcoholics and the rates of ARBD among alcoholic women provide epidemiologic support to the hypothesis that acetaldehyde may play a major role in the cause of ARBD.

Acetaldehyde↗
PubMed2001

Pregnancy outcome following gestational exposure to venlafaxine: a multicenter prospective controlled study.

OBJECTIVE: Because there are no studies available on the safety of venlafaxine during pregnancy, the authors' goal in this study was to determine whether venlafaxine increases the risk for major malformations. METHOD: Data on 150 women exposed to venlafaxine during pregnancy in seven pregnancy counseling centers were compared with data from studies of pregnant women who 1) received selective serotonin reuptake inhibitor antidepressants (SSRIs) (N=150) and 2) who received nonteratogenic drugs (N=150). RESULTS: Among the 150 women who were exposed to venlafaxine during pregnancy, 125 had live births, 18 had spontaneous abortions, and seven had therapeutic abortions; two of the babies had major malformations. There were no significant differences between these women and the two comparison groups on any of the measures analyzed. CONCLUSIONS: These results suggest that the use of venlafaxine during pregnancy does not increase the rates of major malformations above the baseline rate of 1%-3%.

Abnormalities, Drug-Induced↗
PubMed2001

Clinical and economic factors in the treatment of behavioural and psychological symptoms of dementia.

The prevalence of behavioural and psychological symptoms of dementia (BPSD) exceeds 50%. They cause distress to patients and caregivers, increase resource utilisation of various kinds, and form a high risk for accelerated psychiatric care through institutionalisation. Although evidence for current pharmacological treatment is not strong and the construct of BPSD is still not very clear, future aspects of treatment of BPSD may be positive. If we look at overall success rates of the antipsychotics, the traditional antipsychotics have the highest combined success rate of 63.1%, whereas the novel antipsychotics have an overall success rate of 56.1%. Haloperidol is the drug with the highest success rate of 65.4%, although this drug is associated with parkinsonian adverse drug reactions. Newer antipsychotics show promise in treating BPSD, but more convincing evidence (e.g. from randomised clinical trials) is required. We provide an overview of the clinical, epidemiological and economic aspects of BPSD and a review of the available literature on their pharmacological treatment. Although only 1 pharmacoeconomic study has been conducted on BPSD, it seems likely that these manifestations drastically increase the burden of dementia.

Aged↗
PubMed2001

Economic evaluation of a new acellular vaccine for pertussis in Canada.

OBJECTIVE: Pertussis is a highly contagious infection affecting mainly children. Acellular pertussis vaccines were recently introduced in Canada based on evidence of improved safety and efficacy over whole cell vaccines, the current standard of care. The following study reports the economic impact of replacing the whole cell vaccine (wP) by a new acellular vaccine (aP) in the Ontario pertussis immunisation programme. DESIGN: For a hypothetical cohort of 100,000 children from birth to the age of 8 years, the costs and consequences of pertussis vaccination with either aP or wP were compared. A decision analytical model was constructed for vaccine delivery, treatment of pertussis cases and vaccine adverse events, with analyses from the viewpoints of the Ontario Ministry of Health and society. MAIN OUTCOME MEASURES AND RESULTS: The main outcomes were expected number of pertussis cases, hospitalisations, and workdays lost by parents. Data on vaccine effectiveness, pertussis incidence, and other parameters used in the model were from published literature. Costs were discounted at 5%, and extensive sensitivity analyses were undertaken. Over 8 years, in a cohort of 100,000 children, the introduction of aP would prevent 10,500 cases of pertussis, avoiding 504 hospital admissions and 73,500 days of work absence. For Ontario, healthcare cost savings over the same period would amount to 275,585 Canadian dollars ($Can), and societal savings to $Can9,752,864

Canada↗
PubMed2001

Examining the Saskatchewan health drug database for antidepressant use: the case of fluoxetine.

OBJECTIVE: To examine the use of fluoxetine in an adult population in Saskatchewan. METHODS: All adults in the Saskatchewan health care databases who had begun fluoxetine therapy between January 1992 and June 1996 and had not received an antidepressant in the six months before the index fluoxetine prescription were identified. Fluoxetine use for the subsequent six-month period was examined. The rates of completion of six months of fluoxetine, rates of stopping, switching to another serotonin-selective reuptake inhibitor (SSRI) or other class of antidepressant, resumption of fluoxetine, as well as average dosages taken and mean duration of therapy were determined. Rates were summarized as means with standard deviation. RESULTS: Data were obtained for 11,322 subjects, of whom 68.2% were women; 17.4% were 65 years of age or older. The average prescribed daily dose of fluoxetine was 22.5 mg (SD=21.7) and the average duration was 88.1 days (SD=57.2). Only 18.9% of patients filled prescriptions for six months, 7049 (62.3%) stopped fluoxetine at least once for one month or more, and 17.3% were titrated to a higher dose, on average 71 days (SD=44) after the initiation of fluoxetine. The proportion of patients switching to another antidepressant was 13.6% (3.3% to another SSRI, 10.3% to other classes), after a mean of 69 days (SD=51) of fluoxetine treatment. CONCLUSIONS: The authors' data suggest that there is a potential underutilization of fluoxetine in the study population. Further research may be warranted to determine the proportion of depressed patients in this population and to better understand the stop-switch-resume pattern of antidepressant use.

Age Distribution↗
PubMed2001

Pharmacoeconomic evaluation of clozapine in treatment-resistant schizophrenia: a cost-utility analysis.

The high costs and efficacy of clozapine warrant a systematic pharmacoeconomic evaluation to assess its relative cost-utility compared with that of older antipsychotic therapies. An economic analysis of clozapine consisted of a meta-analysis and a cost-utility analysis. Clozapine was compared with haloperidol and chlorpromazine. An incidence-based deterministic decision analysis was used to model the management of chronic schizophrenia over one year. Probabilities of clinical outcomes were obtained from a random effects, single arm meta-analysis. Utility weights were evaluated in a cohort of patients by using a standard gamble methodology. A government payer perspective was adopted for this analysis. Clozapine was the dominant therapy in this analysis because it was associated with the lowest overall expected cost and highest expected number of quality-adjusted life years (QALYs). Compared with chlorpromazine, clozapine might save $38,879/year while producing 0.04 more QALYs. This analysis was limited in that studies were of short duration, the sample size for health utility analysis was small and the analysis was based on a model. Clozapine appears to be a very cost effective therapy in patients with treatment-resistant schizophrenia compared with haloperidol and chlorpromazine.

Antipsychotic Agents↗
PubMed2000

Child care center staff contribute to physician visits and pressure for antibiotic prescription.

OBJECTIVE: To determine whether child care center (CCC) providers contribute to unnecessary physician referrals and antibiotic prescriptions in young children with upper respiratory tract infections. DESIGN: A survey using a structured telephone questionnaire between May 3, 1998, and July 27, 1998. PARTICIPANTS: Child care center providers from randomly selected licensed Ontario CCCs accepting diapered children. MAIN OUTCOME MEASURES: Knowledge, attitudes, and practices concerning physician referral; exclusion; and antibiotic use for children with upper respiratory tract infections. Indications for exclusion were compared with published Canadian guidelines. RESULTS: Contact was made with 42 eligible CCCs to obtain the requisite number of 36 participants (participation rate, 86%). Of the 36 centers, staff reported advising that children visit a physician for colored nasal discharge in 28 (78%), for productive cough in 23 (64%), and for unusual behavior in 9 (25%). Also of the 36 centers, staff reported excluding children for colored nasal discharge in 20 (56%), for productive cough in 16 (44%), and for unusual behavior in 15 (42%). Antibiotics were thought useful for nonspecific upper respiratory tract infections to prevent the spread of infection in 9 (26%), to speed up recovery in 7 (21%), and to prevent bacterial infection in 13 (38%) of 34 centers. In the previous 6 months, 25 (69%) of 36 staff members reported making an exception to exclusion because a child had an antibiotic prescription. CONCLUSIONS: Many children are referred by CCC staff to physicians contrary to established guidelines. As staff must act on behalf of parents, a low threshold for referral is not unreasonable. However, this survey confirms that CCC staff recommend children to receive antibiotics and exclude children inappropriately. These practices are based on incomplete knowledge. Research on appropriate management of upper respiratory tract infections by CCC staff is needed. Education to correct specific knowledge deficits should be initiated.

Anti-Bacterial Agents↗
PubMed2000

Birth defects after maternal exposure to corticosteroids: prospective cohort study and meta-analysis of epidemiological studies.

BACKGROUND: Corticosteroids are first-line drugs for the treatment of a variety of conditions in women of childbearing age. Information regarding human pregnancy outcome with corticosteroids is limited. METHODS: We collected prospectively and followed up 184 women exposed to prednisone in pregnancy and 188 pregnant women who were counseled by Motherisk for nonteratogenic exposure. The primary outcome was the rate of major birth defects. A meta-analysis of all epidemiological studies was conducted. The Mantel-Haenszel summary odds ratio was calculated for the pooled studies with 95% confidence intervals. A cumulative summary odds ratio was also calculated by combining studies in chronological order. Chi-squared for homogeneity was determined to establish the comparability of the studies. RESULTS: In our prospective study, there was no statistical difference in the rate of major anomalies between the corticosteroid-exposed and control groups. In the meta-analysis, the Mantel-Haenszel summary odds ratio for major malformations with all cohort studies was 1.45 [95% CI 0.80, 2.60] and 3.03 [95% CI 1.08, 8. 54] when Heinonen et al. ('77) was removed. This suggests a marginally increased risk of major malformations after first-trimester exposure to corticosteroids. In addition, summary odds ratio for case-control studies examining oral clefts was significant (3.35 [95% CI 1.97, 5.69]). CONCLUSIONS: Although prednisone does not represent a major teratogenic risk in humans at therapeutic doses, it does increase by an order of 3.4-fold the risk of oral cleft, which is consistent with the existing animal studies.

Abnormalities, Drug-Induced↗
PubMed2000

Meta-analysis of the effect of latanoprost and brimonidine on intraocular pressure in the treatment of glaucoma.

OBJECTIVE: The purpose of this study was to indirectly quantify and compare the intraocular pressure (IOP)-lowering effects of latanoprost and brimonidine eye drops at baseline and after 3 and 6 months in the treatment of primary open-angle glaucoma. METHODS: This meta-analysis combined data from all randomized controlled trials comparing the effects on IOP of latanoprost and brimonidine treatment in adults with a baseline IOP > or =20 mm Hg. MEDLINE and EMBASE were searched for reports of the ophthalmic administration of either drug versus the other, placebo, or active therapy. Included studies reported IOP as either means or differences (with SD or SE) and sample sizes. A random-effects model was used to pool data within each drug group. As a proxy for success rates, area under the curve (AUC) was calculated for the proportion of patients having an IOP <20 mm Hg. RESULTS: One hundred fifty-five articles reporting on 158 trials were identified; 147 papers were rejected (141 were not randomized controlled trials, 5 were duplicates, and 1 had nonextractable data), leaving 9 trials from 8 articles. A total of 2152 patients were included in the meta-analysis: 597 received latanoprost, 571 received brimonidine, and the remainder received timolol or betaxolol. Baseline IOPs were similar in patients randomized to latanoprost or brimonidine (25.3 and 24.6 mm Hg, respectively). At 3 months, latanoprost and brimonidine reduced IOP by 8.4 and 6.5 mm Hg, respectively (P = 0.004 latanoprost vs brimonidine), and at 6 months by 8.0 and 6.2 mm Hg, respectively (P = 0.045). AUC was 0.834 and 0.675 at 3 months for latanoprost and brimonidine, respectively, and 0.817 and 0.715 at 6 months, respectively (both, P < 0.001). CONCLUSIONS: This indirect comparison of data from the available randomized clinical trials showed latanoprost to be statistically superior to brimonidine in reducing IOP in adults with primary open-angle glaucoma. Additional long-term, head-to-head comparisons of the efficacy, safety, and cost of latanoprost and brimonidine are needed to support and supplement these findings.

Brimonidine Tartrate↗
PubMed2000

Can we use anxiolytics during pregnancy without anxiety?

QUESTIONOne of my patients suffers from anxiety and was using lorazepam to treat it. When she became pregnant, she stopped the medication immediately, but now she is worried about the potential effect on the baby because she was using the drug just after conception. Is this class of drugs safe during pregnancy? What should she do if she needs antianxiety treatment during the rest of her pregnancy?ANSWEREvidence to date from cohort studies did not identify a notable association between use of benzodiazepines and increased risk of major malformations, including oral cleft. In contrast, data from case-control studies show a slightly increased risk of oral cleft. Hence, level 2 ultrasonography is recommended to rule out visible forms of cleft lip. Using benzodiazepines late in pregnancy could cause withdrawal syndrome in newborns.

Anti-Anxiety Agents↗
PubMed1999

Meta-analytic review of the clinical effectiveness of oral deferiprone (L1).

OBJECTIVE: To summarize efficacy and effectiveness in iron overloaded patients treated with the orally active iron chelator deferiprone also known as L1 or, using meta-analysis of the literature. METHODS: We reviewed the literature, searching Medline and Embase databases, as well as reviews and other literature on the topic. Inclusion criteria were: original clinical trials reporting results for serum ferritin concentration (SF), hepatic iron concentration or urinary iron excretion (UIE). Efficacy data had to have been reported after > or =3 months of treatment. Data were combined using a random effects model (Cochrane) modified for use with single groups to produce a point estimate and a 95% confidence interval. To summarize the clinical effectiveness, overall proportion of patients where deferiprone was able to reduce serum ferritin was calculated. We also examined average (mg x l(-1)) serum ferritin levels over the reported time (mean) and absolute decrease from the baseline after therapy. To summarize efficacy, success was defined as the proportion of patients who achieved UIE of 25 mg per day or 0.5 mg x kg(-1) x day(-1), which equals the average amount received from monthly blood transfusions. We also calculated the overall average level (mg per day) of UIE over the reported time of therapy (mean). As part of a sensitivity analysis, data were analyzed for two ranges of deferiprone dosage: < or = 50 mg x kg(-1) x day(-1) and > or =75 mg x kg(-1) x day(-1). RESULTS: Of 83 identified references, nine clinical trials met our inclusion criteria, providing data for 129 iron overloaded patients. After a mean of 16 months of therapy (range 6.4 36 months) with 66.4 mg x kg(-1) x day(-1) (mean) of deferiprone, 75.5% of highly iron overloaded patients had a decrease in serum ferritin from baseline. The average drop in serum ferritin of 0.8 mg x l(-1) was 23.5% from baseline. The overall average UIE for therapy was 28.8 mg per day in patients receiving > or = 75 mg x kg(-1) x day(-1) over 8.5 months of therapy. At the same dosage, more than half of the patients (51.8%) achieved negative iron balance. When studies with patients receiving lower dosage (< or = 50 mg x k(-1) x day(-1)) were included, the success rate was 45.1%. CONCLUSION: Overall, deferiprone has clinical efficacy in achieving negative iron balance and reducing body iron burden in highly iron overloaded patients. After an average of 16 months of deferiprone in doses > or = 75 mg x kg(-1) x day(-1), most patients had a decrease in ferritine concentration.

Administration, Oral↗
PubMed1999

Comparison of extended-release venlafaxine, selective serotonin reuptake inhibitors, and tricyclic antidepressants in the treatment of depression: a meta-analysis of randomized controlled trials.

The purpose of this study was to summarize and compare the clinical success rates of extended-release venlafaxine, some selective serotonin reuptake inhibitors (SSRIs), and certain tricyclic antidepressants (TCAs). A meta-analytic approach was used to synthesize outcomes from published randomized controlled trials involving patients scoring > or =15 on the Hamilton Rating Scale for Depression (HAM-D) or > or =18 on the Montgomery-Asberg Depression Rating Scale (MADRS). Searches of the MEDLINE, EMBASE, and International Pharmaceutical Abstracts databases were performed, as were searches of references from retrieved articles and reviews. Drugs included in the comparison were extended-release venlafaxine (venlafaxine-XR); the SSRIs citalopram, fluoxetine, fluvoxamine, paroxetine, and sertraline; and the TCAs amitriptyline, imipramine, desipramine, and nortriptyline. Therapeutic success was defined as a 50% decrease in the HAM-D or MADRS score. Data were extracted by 2 independent evaluators, with differences resolved through consensus discussions. Weighted mean success rates were calculated for each drug class, using a random-effects model. The resulting data represent 44 trials with 63 study arms and 4033 patients with depression. Venlafaxine-XR demonstrated a 73.7% success rate, which was statistically significantly greater than that of the studied SSRIs (61.1%) and TCAs (57.9%) (P<0.001). Thus this meta-analysis of randomized controlled studies of patients with depression suggests that venlafaxine-XR is clinically superior in efficacy to SSRIs and TCAs. Venlafaxine-XR also had universally lower, though nonsignificant, dropout rates.

Antidepressive Agents, Second-Generation↗
PubMed1999

Antibiotic prescribing for Canadian preschool children: evidence of overprescribing for viral respiratory infections.

Antibiotic resistance is associated with prior receipt of antibiotics. An analysis of linked computerized databases for physician visits and antibiotic prescriptions was used to examine antibiotic prescribing for different respiratory infections in preschool children in Canada. In 1995, 64% of 61,165 children aged <5 years made 140,892 visits (mean, 3.6 visits per child) for respiratory infections; 74% of children who made visits received antibiotic prescriptions. Antibiotics were prescribed to 49% of children with upper respiratory tract infection, 18% with nasopharyngitis, 78% with pharyngitis or tonsillitis, 32% with serous otitis media, 80% with acute otitis media, 61% with sinusitis, 44% with acute laryngitis or tracheitis, and 24% with influenza. Acute otitis media accounted for 33% of all visits and 39% of all antibiotic prescriptions. The estimated Canadian-dollar cost of overprescribing was $423,693, or 49% of the total cost of antibiotics ($859,893) used in this group. This population-based study confirms antibiotic overprescribing in Canada.

Anti-Bacterial Agents↗
PubMed1999

Reproducibility of medical information obtained via the telephone vs personal interview.

The Motherisk [corrected] Program, a teratogenic information service, conducts patient interviews over the telephone as well as in a clinic setting. In both instances, medical information and exposure history is obtained from the patient, including such items as pregnancy history, drug exposure, alcohol and smoking habits. It occurred on several occasions that the clinic interviewer remarked that the same patient had volunteered information to them, that differed from the information documented on the intake telephone form. The objective of the study was to establish the levels of agreement in the documentation, between these two forms of interviews. Two groups of 100 paired telephone and clinic forms were randomly selected from our data base, 1990-1991 and 1996-1997. These two groups were chosen to assess if there were any differences over a five year time period. Statistical calculations were performed using the Kappa statistic, a method that measures agreement. Kappa scores indicated high reproducibility for both pregnancy and smoking history, good reproducibility for medical history, marginal-good for exposures (although excellent agreement was found for the primary drug of concern) and marginal-good for alcohol information. Overall, agreement was superior in the 1990-1991 group. There were marked differences in consistency, between the information recorded on the telephone form and the clinic form, most specifically relating to secondary exposures and alcohol history. It suggests that a person to person interview yields a more complete medical history than a telephone interview.

Alcohol Drinking↗
PubMed1998

Benzodiazepine use in pregnancy and major malformations or oral cleft: meta-analysis of cohort and case-control studies.

OBJECTIVE: To determine if exposure to benzodiazepines during the first trimester of pregnancy increases risk of major malformations or cleft lip or palate. DESIGN: Meta-analysis. SETTING: Studies from 1966 to present. SUBJECTS: Studies were located with Medline, Embase, Reprotox, and from references of textbooks, reviews, and included articles. Included studies were original, concurrently controlled studies in any language. INTERVENTIONS: Data extraction and quality assessment were done independently and in duplicate. MAIN OUTCOME MEASURES: Maternal exposure to benzodiazepines in at least the first trimester; incidence of major malformations or oral cleft alone, measured as odds ratios and 95% confidence intervals with a random effects model. RESULTS: Of over 1400 studies reviewed, 74 were retrieved and 23 included. In the analysis of cohort studies fetal exposure to benzodiazepine was not associated with major malformations (odds ratio 0.90; 95% confidence interval 0.61 to 1. 35) or oral cleft (1.19; 0.34 to 4.15). Analysis of case-control studies showed an association between exposure to benzodiazepines and development of major malformations (3.01; 1.32 to 6.84) or oral cleft alone (1.79; 1.13 to 2.82). CONCLUSIONS: Pooled data from cohort studies showed no association between fetal exposure to benzodiazepines and the risk of major malformations or oral cleft. On the basis of pooled data from case-control studies, however, there was a significant increased risk for major malformations or oral cleft alone. Until more research is reported, level 2 ultrasonography should be used to rule out visible forms of cleft lip.

Abnormalities, Drug-Induced↗