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David Henry

Publications and source records attributed to David Henry.

At least 37 records · Page 2Linked to original sources
PubMed2004

Grading quality of evidence and strength of recommendations.

Users of clinical practice guidelines and other recommendations need to know how much confidence they can place in the recommendations. Systematic and explicit methods of making judgments can reduce errors and improve communication. We have developed a system for grading the quality of evidence and the strength of recommendations that can be applied across a wide range of interventions and contexts. In this article we present a summary of our approach from the perspective of a guideline user. Judgments about the strength of a recommendation require consideration of the balance between benefits and harms, the quality of the evidence, translation of the evidence into specific circumstances, and the certainty of the baseline risk. It is also important to consider costs (resource utilisation) before making a recommendation. Inconsistencies among systems for grading the quality of evidence and the strength of recommendations reduce their potential to facilitate critical appraisal and improve communication of these judgments. Our system for guiding these complex judgments balances the need for simplicity with the need for full and transparent consideration of all important issues.

Cost-Benefit Analysis↗
PubMed2004

Omapatrilat and enalapril in patients with hypertension: the Omapatrilat Cardiovascular Treatment vs. Enalapril (OCTAVE) trial.

BACKGROUND: Recent reports suggest that existing antihypertensive agents may not have sufficient efficacy to control blood pressure (BP) in many patients. Omapatrilat, an agent under development, has been shown to have significantly greater antihypertensive efficacy than existing agents, but may also carry increased risk of angioedema. We compared the efficacy and safety of omapatrilat to a representative angiotensin-converting enzyme (ACE) inhibitor, enalapril. METHODS: The Omapatrilat Cardiovascular Treatment vs. Enalapril (OCTAVE) trial is a multicenter, randomized, double-blind, active-controlled, 24-week trial in 25,302 patients with untreated or uncontrolled hypertension conducted in 3298 office-based sites in 12 countries. Subjects were randomized to omapatrilat 10 mg or enalapril 5 mg as initial therapy for hypertension (group 1, n = 9292), replacement for existing antihypertensive therapy (group 2, n =11,224), or in addition to existing antihypertensive therapy (group 3, n = 4751). Study drug was force-titrated at week 2 and electively titrated at weeks 4 and 6 to a maximum of omapatrilat 80 mg or enalapril 40 mg once daily. At weeks 8 and 16, adjunctive antihypertensive medications were added electively to achieve target BP. RESULTS: Omapatrilat reduced systolic BP 3.6 mm Hg more than enalapril at week 8, and was associated with less use of adjunctive antihypertensive therapy by week 24 (19% v 27%; P < 0.001 for both comparisons). Subjects randomized to omapatrilat were more likely to reach BP target, regardless of demographics or comorbid conditions and whether omapatrilat was used as initial therapy, replacement for existing therapy, or in addition to existing therapy. Angioedema was more frequent with omapatrilat than enalapril (2.17% v 0.68%). Two omapatrilat-treated subjects experienced angioedema with airway compromise, which was successfully treated. CONCLUSIONS: Omapatrilat provided broadly superior antihypertensive efficacy when used in a setting resembling clinical practice. Angioedema was more common than with enalapril but life-threatening angioedema was rare. The risk-benefit profile for omapatrilat in clinical use therefore appears likely to be favorable in appropriate patients.

Adolescent↗
PubMed2004

Supporting families in a high-risk setting: proximal effects of the SAFEChildren preventive intervention.

Four hundred twenty-four families who resided in inner-city neighborhoods and had a child entering 1st grade were randomly assigned to a control condition or to a family-focused preventive intervention combined with academic tutoring. SAFEChildren, which was developed from a developmental-ecological perspective, emphasizes developmental tasks and community factors in understanding risk and prevention. Tracking of linear-growth trends through 6 months after intervention indicated an overall effect of increased academic performance and better parental involvement in school. High-risk families had additional benefits for parental monitoring, child-problem behaviors, and children's social competence. High-risk youth showed improvement in problem behaviors and social competence. Results support a family-focused intervention that addresses risk in low-income communities as managing abnormal challenges.

Child↗
PubMed2004

Patient co-payments and use of prescription medicines.

OBJECTIVE: To investigate how prescription co-payments influence the medicine use of Australian patients. METHODS: Two surveys and an in-depth interview study were conducted in the Newcastle/Hunter region of New South Wales (NSW). A community-based survey explored how often prescription cost posed a barrier to prescription use. A general practice patient survey investigated the impact of prescription cost on the timing of medical consultations and prescription collection. Quantitative data were summarised using descriptive statistics; associations between household characteristics and outcomes were explored using odds ratios and chi square analysis. In-depth interviews were conducted to explore the role of prescription cost in medicine use. The interview data were qualitatively analysed for relevant themes using 'grounded theory'. RESULTS: 420 of 950 households (44%) participated in the community survey: 110 (26%) reported delaying visiting a GP, 85 (20%) not buying all of their prescription medicines and 77 (18%) not refilling a prescription because of cost. Sixty-two (15%) households reported significant difficulties with prescription costs. Households with children had twice the odds of reporting significant difficulties than those without (OR= 2.0, 95% CI 1.2-3.5). Of the 442 (43%) GP patients who participated, 25 (6%) patients reported prescription cost as the reason for delaying their visit. Of the 291 patients who received a prescription, 26 (9%) patients reported cost as the reason for not collecting some or all of their prescriptions. IMPLICATIONS: Given the wide variation in patients' capacity to manage increased out-of-pocket costs, co-payments may add to patients' burden and place a potential barrier to safe and timely prescription use.

Cost Sharing↗
PubMed2004

Single-enantiomer drugs: elegant science, disappointing effects.

Most new drugs are marketed as single enantiomers but many older agents are still available in racemic form. As these drugs reach the end of their patent life manufacturers become interested in marketing single enantiomer equivalents. This is called 'chiral switching' and it has been claimed that it will bring clinical benefits in terms of improved efficacy, more predictable pharmacokinetics or reduced toxicity. We reviewed the clinical evidence and prices for three recently marketed single enantiomer versions of widely used racemic drugs: escitalopram, esomeprazole and levosalbutamol. Claims of increased efficacy were based on comparisons of non-equivalent doses and any advantages seemed small and clinically unimportant. Prices of esomeprazole and levosalbutamol were higher than their racemic alternatives and we predict that these prices will remain high despite the market presence of generic versions of the racemates. Patent protection and a perception of superiority based on promotion rather than evidence will maintain price premiums for single enantiomer drugs that are not justified on the basis of clinical performance.

Albuterol↗
PubMed2003

Patent law.

Explore the source record for details and available documents.

Developing Countries↗
PubMed2003

Bridges to Iran.

Explore the source record for details and available documents.

Democracy↗
PubMed2003

9-cis-retinoic acid capsules in the treatment of AIDS-related Kaposi sarcoma: results of a phase 2 multicenter clinical trial.

OBJECTIVE: To evaluate the safety, dose tolerance, and anti-tumor effects of 9-cis-retinoic acid in the treatment of Kaposi sarcoma (KS) related to acquired immunodeficiency syndrome (AIDS). DESIGN: Phase 2, open-label clinical trial of oral doses of 9-cis-retinoic acid increasing in 40-mg increments every 2 weeks from 60 mg/m(2) per day to a maximum of 140 mg/m( 2) per day. SETTING: Five hospital or health maintenance organization outpatient clinics. PATIENTS: Fifty-seven adult male patients with human immunodeficiency virus and biopsy-proven KS. MAIN OUTCOMES MEASURES: Safety was evaluated by adverse events, physical examination, laboratory test abnormalities, treatment-limiting toxic effects, and reasons for early withdrawal. Response (>/=50% improvement) was evaluated by an overall KS response and by the area and height from 6 index lesions selected at baseline. RESULTS: Patients tolerated 60 and 100 mg/m(2) per day. Most patients found 140 mg/m(2) per day intolerable owing to headache. Common treatment-related adverse events were headache, xerosis, rash, alopecia, and hyperlipemia. The patient response rate for the overall KS disease was 19% (11/57), including 1 patient with clinically complete response. The response rate assessed by measuring 6 index lesions during treatment was 39% (22/57). Sixteen responding patients (73%) were refractory to at least 1 previous anti-KS therapy. Patients with CD4( +) counts of 150 cells/ micro L or lower were as likely to respond as patients with counts of higher than 150 cells/ micro L. The median time to response was 8.5 weeks (range, 4.0-21.1 weeks). The median duration of treatment was 15.1 weeks (range, 0.14 to >/=62 weeks). CONCLUSION: 9-cis-retinoic acid capsules have moderate activity and provide durable responses, but substantial toxic effects at higher doses limit its suitability as an anti-KS therapy.

Acquired Immunodeficiency Syndrome↗
PubMed2003

Describing treatment effects to patients.

OBJECTIVE: To examine the impact of different presentations of equivalent information (framing) on treatment decisions faced by patients. DESIGN: A systematic review of the published literature was conducted. English language publications allocating participants to different frames were retrieved using electronic and bibliographic searches. Two reviewers examined each article for inclusion, and assessed methodological quality. Study characteristics were tabulated and where possible, relative risks (RR; 95% confidence intervals) were calculated to estimate intervention effects. MEASUREMENTS AND MAIN RESULTS: Thirty-seven articles, yielding 40 experimental studies, were included. Studies examined treatment (N = 24), immunization (N = 5), or health behavior scenarios (N = 11). Overall, active treatments were preferred when outcomes were described in terms of relative rather than absolute risk reductions or number needed to treat. Surgery was preferred to other treatments when treatment efficacy was presented in a positive frame (survival) rather than a negative frame (mortality) (relative risk [RR] = 1.51, 95% confidence interval [CI], 1.39 to 1.64). Framing effects were less obvious for immunization and health behavior scenarios. Those with little interest in the behavior at baseline were influenced by framing, particularly when information was presented as gains. In studies judged to be of good methodological quality and/or examining actual decisions, the framing effect, although still evident, was less convincing compared to the results of all included studies. CONCLUSIONS: Framing effects varied with the type of scenario, responder characteristics, scenario manipulations, and study quality. When describing treatment effects to patients, expressing the information in more than one way may present a balanced view to patients and enable them to make informed decisions.

Communication↗
PubMed2003

Epidemiology overview of gastrointestinal and renal toxicity of NSAIDs.

This review updates previous systematic reviews to explore the overall levels of risk of serious upper gastrointestinal complications of treatment with non-steroidal anti-inflammatory drugs (NSAIDs) and to investigate the importance of dose in explaining variations in risk. Thirty-six eligible case control studies were published between 1985 and 2000 and involved 19,648 cases and 105,373 controls. Eight eligible cohort studies included around 400,000 exposed subjects and 1 million non-exposed controls. The pooled unadjusted odds ratio from case control studies (compared with non-use of NSAIDs) for serious gastrointestinal complications is 4.06 (CI95% 3.47, 4.75); the pooled odds ratio from cohort studies is 2.29 (CI95% 1.50, 3.51). Unadjusted odds ratios range from 1.81 for ibuprofen to 7.46 for piroxicam. These data require careful interpretation because the statistical power of analyses of individual NSAIDs is lower than that for the class as a whole. There is a rank order of risk for different NSAIDs at low doses but at higher doses the odds ratios tend to converge. Ibuprofen is associated with a lower risk of serious gastrointestinal complications than other NSAIDs; this advantage is probably lost at higher doses (>1800 mg/day).

Anti-Inflammatory Agents, Non-Steroidal↗
PubMed2003

A controlled Phase II trial assessing three doses of enfuvirtide (T-20) in combination with abacavir, amprenavir, ritonavir and efavirenz in non-nucleoside reverse transcriptase inhibitor-naive HIV-infected adults.

Enfuvirtide is a novel antiretroviral that blocks HIV-1 cell fusion and viral entry. This Phase II, controlled, open-label, randomized, multicentre dose-ranging trial explored the safety, antiviral activity and pharmacokinetics of enfuvirtide, administered by subcutaneous (s.c.) injection, in 71 HIV-1-infected, protease inhibitor-experienced, non-nucleoside reverse transcriptase inhibitor (NNRTI)-naive adults for 48 weeks. Study participants were randomized to receive enfuvirtide at a deliverable dose of 45, 67.5 or 90 mg twice daily; the 45 mg twice daily dose required 2 injections/day, while the higher doses required 4 injections/day. A background oral antiretroviral (ARV) regimen of abacavir (300 mg twice daily), amprenavir (1200 mg twice daily), ritonavir (200 mg twice daily) and efavirenz (600 mg once daily) was provided with enfuvirtide. A control group received the background ARV regimen alone. All potential participants underwent an HIV genotype at screen to ensure a homogenous population and to exclude patients with evidence of genotypic resistance to NNRTIs. Overall, the tolerability of the combination of abacavir, amprenavir, ritonavir, efavirenz and enfuvirtide was generally comparable to control through 48 weeks. No enfuvirtide dose-dependent adverse events (AEs) were observed across treatment groups. Injection site reactions (ISRs) occurred at least once in 68.5% of the enfuvirtide-treated population, and most ISRs were mild to moderate in severity, with no apparent dose relationship. Excluding ISRs, the most common treatment-emergent AEs were nausea, diarrhoea, dizziness and fatigue; with no clinically significant differences in the incidence of AEs observed between the control and enfuvirtide groups. Each treatment group benefited from ARV therapy, with a trend of increasing antiviral and immunological activity associated with increasing enfuvirtide dose. At 48 weeks, the median HIV-1 RNA change from baseline for the ITT population was -2.24 log10 copies/ml for the combined enfuvirtide groups compared with -1.87 log10 copies/ml for the control group. In addition, 54.9% of patients in the enfuvirtide group achieved HIV-1 RNA < or = 400 copies/ml versus 36.8% of patients in the control group. These results indicate that enfuvirtide has a favourable safety profile and is a promising new antiviral agent for HIV-infected patients who have been on previously failing ARV regimens.

Adult↗
PubMed2002

The pharmaceutical industry as a medicines provider.

Rising prices of medicines are putting them beyond the reach of many people, even in rich countries. In less-developed countries, millions of individuals do not have access to essential drugs. Drug development is failing to address the major health needs of these countries. The prices of patented medicines usually far exceed the marginal costs of their production; the industry maintains that high prices and patent protection are necessary to compensate for high development costs of innovative products. There is controversy over these claims. Concerns about the harmful effects of the international system of intellectual property rights have led the World Trade Organization to relax the demands placed on least developed countries, and to advocate differential pricing of essential drugs. How these actions will help countries that lack domestic production capacity is unclear. Better access to essential drugs may be achieved through voluntary licensing arrangements between international pharmaceutical companies and manufacturers in developing countries.

Developed Countries↗
PubMed2002

Anxiety and fear. Discriminant validity in the child and adolescent practitioner's perspective.

OBJECTIVE: We assessed the ability of child and adolescent practitioners to discriminate between anxiety items from the Revised Children's Manifest Anxiety Scale (RCMAS) and fear items from the Fear Survey Schedule for Children-Revised (FSSC-R). In addition, we examined the effects age, gender, nationality, and therapeutic orientation on discrimination ability. METHOD: Child and adolescent psychiatrists and psychologists from two university hospitals in Australia and the USA completed a questionnaire comprised of items randomly chosen from the RCMAS and the FSSC-R. Clinicians rated each item on the extent to which the item represented the construct of anxiety or fear, using a 7-point Likert-type scale. RESULTS: Clinicians were more accurate in their perceptions of anxiety than in their perceptions of fear. Clinicians with a psychodynamic orientation were more likely to perceive an item as describing anxiety, and were less likely to identify fear. There was a significant interaction between age, scale and perception, with the youngest clinicians showing the greatest perceptual differentiation between the fear and anxiety items. CONCLUSIONS: The results suggest a need to develop common terminology among researchers and clinicians, develop scales with items specific to the pathology they intend to measure, and consider the variables influencing the clinicians rating them.

Adolescent↗
PubMed2002

Transfusion triggers: a systematic review of the literature.

Most clinical practice guidelines recommend restrictive red blood cell (RBC) transfusion practices with the goal of minimizing transmission of blood-borne pathogens. The purpose of this review is to compare clinical outcomes in patients randomized to restrictive versus liberal transfusion thresholds (triggers). We conducted a search of OVID Medline, Current Contents, the Cochrane Library, and bibliographies of published studies. Our search strategies used a combination of key-word terms as text and MeSH headings relating to transfusion triggers. We included trials if the comparison groups were assigned on the basis of a clear transfusion trigger or threshold, and the study was randomized with a concurrent control group. Eligibility of studies was assessed by 2 independent raters, with disagreements resolved by consensus. Disagreements not resolved by consensus were referred to a third party for review. Two raters assessed the methodologic quality of the trials modified from the methods of Schultz. The main study outcomes probability of receiving an RBC transfusion, volume of RBCs transfused, hematocrit levels, mortality, and length of hospital stay. Ten trials, which reported outcomes for a total of 1,780 patients, were included. Five studies were in surgical patients, 3 were in the setting of acute blood loss and trauma, and 2 involved intensive care unit patients. Transfusion triggers varied between 7 and 10 g/dL (most often they were 8 or 9 g/dL). Being randomized to a restrictive transfusion trigger group had the following average effects: the probability of receiving an RBC transfusion was reduced by 42% (relative risk, 0.58; 95% confidence interval [CI] 0.47, 0.71), the volume of RBCs was reduced by 0.93 units (95% CI 0.36, 1.5 units), and hematocrit values were 5.6 % lower (95% CI 3.5, 7.7%). Mortality, rates of cardiac events, morbidity, and length of hospital stay were unaffected. The limited published evidence supports the use of restrictive transfusion triggers in patients who are free of serious cardiac disease. However, most of the data on clinical outcomes were generated by a single trial. The effects of conservative transfusion triggers on functional status, morbidity, and mortality, particularly in patients with cardiac disease, need to be tested in further large clinical trials. In countries with inadequate screening of donor blood, the data may constitute a stronger basis for avoiding transfusion with allogeneic RBCs.

Blood Transfusion↗
PubMed2002

Nurses' use of alcohol and other drugs: findings from a national probability sample.

This study examined the prevalence of alcohol and other drug (AOD) use among nurses in the 1984 National Longitudinal Survey of Youth (NLSY) using methods similar to those employed in a study comparing nurses and nonnurses from the 1980-1984 Epidemiological Catchment Area program (ECA). Conditional logistic regression was used to estimate the degree to which AOD use was associated with occupation. Results indicating that substance use is unrelated to occupation lend support to earlier findings from the ECA.

Adult↗