Biomedical subjects

David C Radley

Publications and source records attributed to David C Radley.

4 recordsLinked to original sources

PubMed2006

Off-label prescribing among office-based physicians.

BACKGROUND: Unlike medicines prescribed for Food and Drug Administration-approved indications, off-label uses may lack rigorous scientific scrutiny. Despite concerns about patient safety and costs to the health care system, little is known about the frequency of off-label drug use or the degree of scientific evidence supporting this practice. METHODS: We used nationally representative data from the 2001 IMS Health National Disease and Therapeutic Index (NDTI) to define prescribing patterns by diagnosis for 160 commonly prescribed drugs. Each reported drug-diagnosis combination was identified as Food and Drug Administration-approved, off-label with strong scientific support, or off-label with limited or no scientific support. Outcome measures included (1) the proportion of uses that were off-label and (2) the proportion of off-label uses supported by strong scientific evidence. Multivariate analyses were used to identify drug-specific characteristics predictive of increased off-label use. RESULTS: In 2001, there were an estimated 150 million (95% confidence interval, 127-173 million) off-label mentions (21% of overall use) among the sampled medications. Off-label use was most common among cardiac medications (46%, excluding antihyperlipidemic and antihypertensive agents) and anticonvulsants (46%), whereas gabapentin (83%) and amitriptyline hydrochloride (81%) had the greatest proportion of off-label use among specific medications. Most off-label drug mentions (73%; 95% confidence interval, 61%-84%) had little or no scientific support. Although several functional classes were associated with increased off-label use (P<.05), few other drug characteristics predicted off-label prescription. CONCLUSIONS: Off-label medication use is common in outpatient care, and most occurs without scientific support. Efforts should be made to scrutinize underevaluated off-label prescribing that compromises patient safety or represents wasteful medication use.

Adult↗

PubMed2003

National trends in antiobesity medication use.

BACKGROUND: The use of medications to treat obesity remains controversial. Our goal was to assess national trends in antiobesity medication use with a focus on patterns surrounding the 1997 removal of antiobesity drugs from the market. METHODS: Using a serial cross-sectional study design, we analyzed a nationally representative sample of US office-based physician visits from 1991 to 2002. Data come from the IMS HEALTH National Disease and Therapeutic Index. These data include a sample of 13 452 patient visits for which a diagnosis of clinical obesity was made, with annual visits ranging from 666 in 1994 to 1854 in 1996. The unit of analysis is the patient visit, while the primary outcome measures are the annual and quarterly number of antiobesity drug mentions for clinically obese patients. RESULTS: At its peak in the second quarter of 1997, 2.5 million Americans were taking antiobesity medications, a 4-fold increase over the prior 2 years. Although antiobesity medication use diminished following the market exit of fenfluramine hydrochloride and dexfenfluramine hydrochloride, current levels of use remain above those in the early 1990s. Phentermine has consistently been the most common antiobesity medication. In 2002, an annualized 1.2 million mentions of phentermine use were noted (31% of drug-treated obese patients). Newly released medications, orlistat (0.6 million) and sibutramine hydrochloride (0.4 million), were used less often. Most antiobesity medication use occurs in patients without other reported medical conditions. CONCLUSIONS: Use of antiobesity medications increased rapidly with public and professional interest in fenfluramine-phentermine (fen-phen) combination therapy. Despite reports of adverse outcomes associated with fenfluramine agents (fen-phen and dexfenfluramine), the use of these medication therapies did not diminish until soon before their removal from the market in 1997.

Anti-Obesity Agents↗

PubMed2003

The underutilization of cardiac medications of proven benefit, 1990 to 2002.

OBJECTIVES: To evaluate recent trends, we examined longitudinal national data on the outpatient use of warfarin in atrial fibrillation (AF), beta-blockers and aspirin in coronary artery disease (CAD), and angiotensin-converting enzyme inhibitors (ACEIs) in congestive heart failure (CHF). BACKGROUND: Previous studies indicate that specific cardiac medications are underutilized. METHODS: We used the National Disease and Therapeutic Index (NDTI) (produced by IMS HEALTH, Plymouth Meeting, Pennsylvania) for 1990 to 2002, and the National Ambulatory Medical Care Surveys (NAMCS) for 1990 to 2000 to follow nationally representative samples of outpatient visits. For visits by patients with AF (total n = 14,634 visits), CAD (n = 35,295), and CHF (n = 33,008), we examined trends in the proportion of visits with the selected medications reported. RESULTS: Warfarin use in AF increased from 12% in 1990, to 41% in 1995, to 58% in 2001 in NDTI; a similar moderation of recent increase was seen in NAMCS. For CAD in NDTI, beta-blocker use increased slowly from 19% in 1990, to 20% in 1995, then to 40% in 2001; NAMCS showed this same pattern. Aspirin use in CAD in NDTI increased from 18% in 1990, to 19% in 1995, to 38% in 2001; NAMCS, however, showed lower use rates. For NDTI, ACEI use in CHF increased from 24% in 1990 to 36% in 1996, but increased to only 39% by 2001, a general pattern also seen in NAMCS. CONCLUSIONS: Both national datasets demonstrate continuing underutilization of these cardiac medications of proven benefit. Although use is increasing, it remains lower than expected, and some increases noted in earlier years have slowed. Substantial public health benefits would result from further adoption of these effective therapies.

Adrenergic beta-Antagonists↗

PubMed2002

The potential of pill splitting to achieve cost savings.

OBJECTIVES: To present a methodology for identifying specific medications for which pill splitting is clinically appropriate and cost saving, to present data from a commercial managed care population on current pill-splitting practices, and to estimate additional cost savings from extended use of this strategy. STUDY DESIGN: Retrospective pharmacy claims analysis. METHODS: Pharmacy claims data from a commercial managed care health plan covering 19,000 lives and national drug data were used to compile a list of frequently prescribed medications. Excluding medications in which packaging, formulation, and potential adverse pharmacologic outcomes prohibited splitting, we performed a cost analysis of medications amenable to splitting. RESULTS: Eleven medications amenable to pill splitting were identified based on potential cost savings and clinical appropriateness: clonazepam, doxazosin, atorvastatin, pravastatin, citalopram, sertraline, paroxetine, lisinopril, nefazadone, olanzapine, and sildenafil. For these medications, pill splitting is currently infrequent, accounting for annual savings of $6200 (or $0.03 per member per month), just 2% of the potential $259,500 (or $1.14 per member per month) that more comprehensive pill-splitting practices could save annually. CONCLUSIONS: Pill splitting can be a cost-saving practice when implemented judiciously using drug- and patient-specific criteria aimed at clinical safety, although this strategy is used infrequently.

Cost Savings↗