Geographic variation in the prescription of schedule II opioid analgesics among outpatients in the United States.

OBJECTIVE: To measure geographic variation in opioid use in a large, commercially insured, outpatient population in the United States. DATA SOURCES: Outpatient prescription drug claims database of a national pharmaceutical benefit manager for 7,873,337 subjects with at least one prescription drug claim in 2000. STUDY DESIGN: We measured the period prevalence of claims for opioid analgesics and controlled-release oxycodone at the state level. We measured geographic variation using the weighted coefficient of variation and systematic component of variation. In county-level multivariable regression, we explored associations between potential explanatory variables and claims for opioid analgesics and controlled-release oxycodone. PRINCIPAL FINDINGS: A total of 567,778 (64.2 per 1,000 total claims) were for oral opioid analgesics. Claim rates by state ranged from <20 to >100 claims per 1,000 total claims. States with long-standing prescription monitoring programs had among the lowest rates. In the county-level data, presence of a statewide prescription monitoring program and proportions of the population aged 15-24 and 65 years and older were independently and negatively associated with claim rates for all opioid analgesics. Surgeons per 1,000, proportion of the population reporting illicit drug use, and proportion who were female were independently and positively associated with claim rates for all opioid analgesics. Only the proportion of the population aged 25-34 and number of surgeons per 1,000 were independently and positively associated with claim rates for oxycodone. CONCLUSIONS: Claim rates for opioid analgesics vary significantly by state. Presence of a statewide prescription monitoring program is associated with lower claim rates at the county level. Future research should use individual-level data to assess whether these findings reflect a reduction in abuse and diversion or suboptimal treatment of pain.

Prevalence of atypical antipsychotic drug use among commercially insured youths in the United States.

BACKGROUND: Use of atypical antipsychotic medications in pediatric populations is increasing. Although previous studies have presented data by age or sex, none has documented sex-specific prevalence by age group. OBJECTIVE: To estimate the 1-year prevalence of atypical antipsychotic use by age and sex among commercially insured youths in the United States. DESIGN: Period prevalence study, January through December 2001. SETTING: Administrative claims database of a large pharmaceutical benefit manager for 6 213 824 outpatients. MAIN OUTCOME MEASURES: Period prevalence of outpatient prescription claims for atypical antipsychotic drugs among commercially insured, continuously enrolled youths. RESULTS: The prevalence of atypical antipsychotic use was 267.1 per 100 000 subjects aged 19 years and younger (16 599/6 213 824) and was more than twice as high for male patients as for female patients, although male and female patients were nearly equally represented in the overall population. Prevalence peaked at 594.3 per 100 000 subjects among male patients aged 10 to 14 years and 291.0 per 100 000 subjects among female patients aged 15 to 19 years. Nearly one fourth (3830/16 599) of patients with a claim for an atypical antipsychotic were aged 9 years and younger, and nearly 80% of these (3021/3830) were boys. CONCLUSIONS: Although evidence regarding the safety and efficacy of atypical antipsychotics in young children is limited, nearly one fourth of patients with claims for these drugs were aged 9 years or younger, and a large majority of these were boys. Understanding the long-term effects on the developing brain of early and prolonged exposure to atypical antipsychotics is crucial given their use in pediatric populations.

Inappropriate prescribing for elderly Americans in a large outpatient population.

BACKGROUND: We sought to determine the extent of potentially inappropriate outpatient prescribing for elderly patients, as defined by the Beers revised list of drugs to be avoided in elderly populations. METHODS: We conducted a retrospective cohort study using the outpatient prescription claims database of a large, national pharmaceutical benefit manager. The cohort included 765,423 subjects 65 years or older, who were covered by a pharmaceutical benefit manager and filed 1 or more prescription drug claims during 1999. Main outcome measures were the proportion of subjects who filled a prescription for 1 or more drugs of concern and the proportion of subjects who filled prescriptions for 2 or more of the drugs. RESULTS: A total of 162,370 subjects (21%) filled a prescription for 1 or more drugs of concern. Amitriptyline and doxepin accounted for 23% of all claims for Beers list drugs, and 51% of those claims were for drugs with the potential for severe adverse effects. More than 15% of subjects filled prescriptions for 2 drugs of concern, and 4% filled prescriptions for 3 or more of the drugs within the same year. The most commonly prescribed classes were psychotropic drugs and neuromuscular agents. CONCLUSIONS: The common use of potentially inappropriate drugs should serve as a reminder to monitor their use closely. Pharmaceutical claims databases can be important tools for accomplishing this task, though clinical and laboratory data are needed to improve the sensitivity and specificity of patient-specific alerts.

Prescription of QT-prolonging drugs in a cohort of about 5 million outpatients.

Many drugs prolong the QT interval and increase the risk of torsade de pointes. Concurrent use of two or more of these drugs can further increase the risk, but the prevalence of concurrent prescription of QT-prolonging drugs is not known. Using the administrative claims database of a national pharmaceutical benefit manager, we conducted a retrospective cohort study in 4,825,345 subjects aged 18 years or older. After identifying 50 drugs with QT-prolonging potential, and an additional 26 drugs that inhibit the metabolic clearance of QT-prolonging drugs, we measured the frequency of overlapping prescriptions for two or more of these drugs in the outpatient setting in 1999. Nearly 1.1 million subjects (22.8%) filled 4.4 million prescriptions for QT-prolonging drugs. Of these, 103,119 subjects (9.4%) filled overlapping prescriptions for two or more of the drugs or for a QT-prolonging drug and another drug that inhibits its clearance; 7249 subjects (0.7%) filled overlapping prescriptions for three or more of these drugs. Twenty-two percent of subjects who filled overlapping prescriptions were aged 65 or older; 74% were women. Antidepressants were involved in nearly 50% of the cases. Concurrent prescription of QT-prolonging drugs is common in the outpatient setting, and antidepressants are involved in half of these cases. Large pharmaceutical claims databases are useful for detecting potentially harmful prescribing behaviors, but better clinical evidence on medication safety is needed before such a system can be implemented fully.

Atypical antipsychotic drugs and diabetes mellitus in a large outpatient population: a retrospective cohort study.

PURPOSE: Previous research has suggested an association between use of atypical antipsychotics and onset of diabetes mellitus. We sought to compare the incidence of new onset diabetes among patients receiving atypical antipsychotics, traditional antipsychotics or antidepressants. METHODS: Retrospective cohort study of outpatients with claims for atypical antipsychotics (n = 10 265) compared to controls with claims for traditional antipsychotics (n = 4607), antidepressants (n = 60 856) or antibiotics (n = 59 878) in the administrative claims database of a large pharmaceutical benefit manager between June 2000 and May 2002. Main outcome measures were adjusted and unadjusted incidence rates of diabetes (new cases per 1000 per year) in a 12-month period, as measured using new prescriptions for antidiabetic drugs after a 6-month lead-in period. RESULTS: Annual unadjusted incidence rates of diabetes (new cases per 1000 per year) were 7.5 for atypical antipsychotics, 11.3 for traditional antipsychotics, 7.8 for antidepressants and 5.1 for antibiotics. In multivariable analyses, age, male sex and Chronic Disease Score were associated with greater odds of diabetes onset. There were no statistically significant differences in outcome between the atypical antipsychotic, traditional antipsychotic and antidepressant groups. Multivariable comparisons among specific agents showed increased odds of diabetes for clozapine, olanzapine, ziprasidone and thioridazine (relative to risperidone), but these comparisons did not reach statistical significance. CONCLUSIONS: In a large prescription claims database, outpatients taking atypical antipsychotics did not have higher rates of diabetes onset, compared to subjects taking traditional antipsychotics or antidepressants.