PubMed Health⌕ Search

Biomedical subjects

Jerry Avorn

Publications and source records attributed to Jerry Avorn.

At least 19 recordsLinked to original sources
PubMed2006

Statins and the risk of lung, breast, and colorectal cancer in the elderly.

BACKGROUND: Although most randomized trials and meta-analyses suggest a slight or no increase in the risk of cancer in statin users, results from observational studies have been conflicting, and some have even suggested a large protective effect of statins on certain cancers. Long-term statin users tend to be healthier, less frail, and more adherent to therapy than nonusers, however. This could explain such apparent "protective" effects. METHODS AND RESULTS: We conducted the present cohort study by linking data from a large state drug benefit program with cancer registry data and Medicare healthcare utilization data. We identified all initiators of statins; initiators of glaucoma medications, another preventive drug, served as a comparison group. Outcomes included all registry-identified cases of colorectal, lung, and breast cancer. Multivariable Cox proportional models were used to adjust for confounding. Patient characteristics were similar in both groups, but statin initiators (n=24,439) were slightly younger and used some services more frequently than glaucoma drug initiators (n=7284). The mean follow-up was 2.9 years, with the longest follow-up being 8.4 years. Incidence rates of colorectal, lung, and breast cancers in both groups were very similar to rates in the general population. Adjusted hazard ratios were 0.96 (95% CI, 0.70 to 1.31) for colorectal cancer, 1.11 (95% CI, 0.77 to 1.60) for lung cancer, and 0.99 (95% CI, 0.74 to 1.33) for breast cancer. CONCLUSIONS: These data from a large population of typical older patients who began using statins indicate that it is unlikely that statins confer a clinically important decrease or increase in the risk of colorectal, lung, or breast cancer over the durations studied.

Aged↗
PubMed2006

Selective prescribing led to overestimation of the benefits of lipid-lowering drugs.

OBJECTIVE: Observational studies have found beneficial effects of lipid-lowering drugs on diverse outcomes, including venous thromboembolism, hip fracture, dementia, and all-cause mortality. Selective use of these drugs in frail people may confound these relationships. STUDY DESIGN AND SETTING: We measured 1-year mortality in two cohorts of New Jersey residents, aged 65-99 years, enrolled in state-sponsored drug benefits programs: 112,463 persons hospitalized during the years 1991-1994 and 106,838 nonhospitalized enrollees. Use of lipid-lowering drugs and other medications, as well as diagnoses, were evaluated before follow-up. RESULTS: In age- and sex-adjusted analyses, users of lipid-lowering drugs had a 43% reduced death rate relative to nonusers among hospitalized enrollees and a 56% reduction in the nonhospitalized sample. Available markers of frailty and comorbidity predicted decreased use of these drugs. Control for the propensity to use lipid-lowering drugs attenuated but did not eliminate these effects. After such adjustment, users had a 30% reduction in death rate (95% confidence interval [CI]: 25%-35%) among hospitalized enrollees and a 41% reduction (95% CI: 35%-47%) in the nonhospitalized sample. Unmeasured frailty associated with a 26%-33% reduced odds of receiving lipid-lowering therapy could explain this effect. CONCLUSION: Frailty and comorbidity that influence use of preventive therapies can substantially confound apparent benefits of lipid-lowering drugs on outcomes.

Age Factors↗
PubMed2006

Variable selection for propensity score models.

Despite the growing popularity of propensity score (PS) methods in epidemiology, relatively little has been written in the epidemiologic literature about the problem of variable selection for PS models. The authors present the results of two simulation studies designed to help epidemiologists gain insight into the variable selection problem in a PS analysis. The simulation studies illustrate how the choice of variables that are included in a PS model can affect the bias, variance, and mean squared error of an estimated exposure effect. The results suggest that variables that are unrelated to the exposure but related to the outcome should always be included in a PS model. The inclusion of these variables will decrease the variance of an estimated exposure effect without increasing bias. In contrast, including variables that are related to the exposure but not to the outcome will increase the variance of the estimated exposure effect without decreasing bias. In very small studies, the inclusion of variables that are strongly related to the exposure but only weakly related to the outcome can be detrimental to an estimate in a mean squared error sense. The addition of these variables removes only a small amount of bias but can increase the variance of the estimated exposure effect. These simulation studies and other analytical results suggest that standard model-building tools designed to create good predictive models of the exposure will not always lead to optimal PS models, particularly in small studies.

Confounding Factors, Epidemiologic↗
PubMed2006

The validity of a rheumatoid arthritis medical records-based index of severity compared with the DAS28.

The objective of this work was to assess the convergent validity of a previously developed rheumatoid arthritis medical records-based index of severity (RARBIS) by comparing it with the 28-joint Disease Activity Score (DAS28). This study was conducted in subjects within the Brigham and Women's Hospital Rheumatoid Arthritis Sequential Study (BRASS). We selected 100 patients with rheumatoid arthritis (RA) from the BRASS with DAS28 scores equally distributed in four quartiles. The medical records were reviewed to calculate the RARBIS, which includes indicators from the following categories: prior surgical history, radiologic and laboratory findings, clinical and functional status, and extra-articular manifestations. The Spearman correlation between the RARBIS and the DAS28 was assessed in the total study population and in relevant subgroups. We re-weighted on subscales and recalculated the RARBIS score. This was performed based on findings of correlations between the DAS28 and subscales; and also the result from a multiple linear regression with the DAS28 (as a dependent variable) and five subscales (as independent variables). The mean RARBIS was 4.36 (range 0-11). Among the total study cohort, the RARBIS was moderately correlated with the DAS28 (r = 0.41, 95% confidence interval [CI] 0.23-0.56). In subgroup analyses, including age, gender, rheumatoid factor status, and disease duration, we found no statistically significant differences in the correlations. After re-weighting, the correlation between the RARBIS and the DAS28 was somewhat improved (r = 0.48, 95% CI 0.31-0.62). In conclusion, the RARBIS correlated moderately well with the DAS28 in this population. The RARBIS has both face and convergent validity for patients with RA and relevant subgroups and may have application for medical records studies in patients with RA.

Arthritis, Rheumatoid↗
PubMed2006

Prescription opioid use among older adults with arthritis or low back pain.

OBJECTIVE: To examine patterns of chronic opioid use in selected groups with arthritis and low back pain and compare them with patterns among persons with ischemic heart disease. METHODS: The study database consisted of Medicare beneficiaries who were enrolled in a drug benefit program for low-to-moderate income Pennsylvania residents. We identified selected patients who had a diagnosis of rheumatoid arthritis, osteoarthritis, chronic low back pain, or ischemic heart disease since 1995. Chronic opioid use, defined as at least six 30-day prescriptions in a year, was the endpoint of interest. We examined the proportion of patients meeting this definition during the period 1996-2001 and determined predictors based on multivariable Cox proportional hazards models. RESULTS: Four percent of subjects with rheumatoid arthritis used opioids chronically in 2001, compared with <1% in each of the other groups. There was no increase in the chronic use of opioids over the 6-year study period. Low-potency opioids were the most commonly prescribed preparations for chronic users from all patient groups. The prior use of medicines for psychiatric illness, including benzodiazepines or barbiturates, was associated with chronic prescription opioid use across all diagnoses. However, subjects with a prior diagnosis of psychiatric illness were less likely to receive chronic opioids. CONCLUSION: Chronic opioid use is relatively uncommon, even among older individuals with arthritis or low back pain. The proportion of these individuals receiving such medicines has not increased in the late 1990s. There seems to be a complex relationship between psychiatric medication use, psychiatric diagnoses, and the use of chronic opioids among these individuals.

Aged↗
PubMed2006

The implications of choice: prescribing generic or preferred pharmaceuticals improves medication adherence for chronic conditions.

BACKGROUND: A large proportion of Americans are enrolled in 3-tier pharmacy benefit plans. We studied whether patients enrolled in such plans who receive generic or preferred brand-name agents when initiating chronic therapy were more adherent to treatment than those who received nonpreferred brand-name medications. METHODS: We analyzed pharmacy claims filled between October 1, 2001, and October 1, 2003, from a large health plan for 6 classes of chronic medications: 3-hydroxy-3-methylglutaryl coenzyme A reductase inhibitors, calcium channel blockers, oral contraceptives, orally inhaled corticosteroids, angiotensin receptor blockers, and angiotensin-converting enzyme inhibitors. We measured adherence as the proportion of days covered (PDC) in each drug class during the first year of therapy. We evaluated how the formulary status of the initial prescription (generic, preferred, or nonpreferred) influenced PDC and adequate adherence, defined as PDC greater than 80%, over the subsequent year. RESULTS: A total of 7532 new prescriptions were filled in 1 of the classes evaluated: 1747 (23.2%) for nonpreferred medications, 4376 (58.1%) for preferred drugs, and 1409 (18.7%) for generic drugs. After controlling for patient sociodemographic characteristics and drug class, PDC was 12.6% greater for patients initiated on generic medications vs nonpreferred medications (58.8% vs 52.2%; P<.001). The PDC was 8.8% greater for patients initiated on preferred vs nonpreferred medications (56.8% vs 52.2%; P<.001). Patients initiated on generic and preferred medications had 62% and 30% greater odds, respectively, of achieving adequate adherence compared with those who received nonpreferred medications. CONCLUSION: In 3-tier pharmacy benefit plans, prescribing generic or preferred medications within a therapeutic class is associated with improvements in adherence to therapy.

Adrenal Cortex Hormones↗
PubMed2006

Medication-attributed adverse effects in placebo groups: implications for assessment of adverse effects.

Medication-attributed adverse effects are a frequent reason for poor compliance in practice and in clinical studies and are also common in patients receiving placebo. The occurrence of adverse effects in placebo groups can clarify the assessment of adverse event reporting. We analyzed data from randomized, placebo-controlled trials of statin drugs published since 1992 with sample sizes larger than 100 subjects. Reports of adverse effects and discontinuation rates in placebo groups were evaluated. We compared data on adverse effect profiles in placebo groups between trials and with expected rates from population-based studies. We also sought to determine the range of adverse effect ascertainment methods used in different studies. Methods of ascertainment of adverse events varied widely across studies. Overall, 4% to 26% of patients in the control groups of large trials of statin drugs discontinued placebo use because of perceived adverse effects. The symptom rate in placebo groups varied substantially across trials (up to a ratio of 13:1 for possibly drug-related symptoms, eg, headache, 0.2%-2.7%, or abdominal pain, 0.9%-3.9%) and were often markedly lower than those found in the general population (eg, fatigue, 1.9%-3.4%) in trials of statin drugs vs 17.7% in the general population. In conclusion, the widely varying rates of adverse effects reported by patients taking placebo and the high prevalence of such symptoms in the general population should be considered by both trialists and clinicians. In addition, variability of adverse effect ascertainment is considerable and suggests the need for better standardization in research.

Adverse Drug Reaction Reporting Systems↗
PubMed2006

The costs and benefits of enhanced depression care to employers.

CONTEXT: Although outreach and enhanced treatment interventions improve depression outcomes, uptake has been poor in part because purchasers lack information on their return on investment. OBJECTIVE: To estimate the costs and benefits of enhanced depression care for workers from the societal and employer-purchaser perspectives. DESIGN: Cost-effectiveness and cost-benefit analyses using state-transition Markov models. Simulated movements between health states were based on probabilities drawn from the clinical literature. PARTICIPANTS: Hypothetical cohort of 40-year-old workers. Intervention Enhanced depression care consisting of a depression screen and care management for those depressed vs usual care. MAIN OUTCOME MEASURES: Our base-case cost-effectiveness analysis was from the societal perspective; costs and quality-adjusted life-years were used to compute the incremental cost-effectiveness of the intervention relative to usual care. A secondary cost-benefit analysis from the employer's perspective tracked monetary costs and monetary benefits accruing to employers during a 5-year time horizon. RESULTS: From the societal perspective, screening and depression care management for workers result in an incremental cost-effectiveness ratio of $19 976 per quality-adjusted life-year relative to usual care. These results are consistent with recent primary care effectiveness trials and within the range for medical interventions usually covered by employer-sponsored insurance. From the employer's perspective, enhanced depression care yields a net cumulative benefit of $2895 after 5 years. In 1-way and probabilistic sensitivity analyses, these findings were robust to a variety of assumptions. CONCLUSION: If these results can be replicated in effectiveness trials directly assessing effects on work outcomes, they suggest that enhanced treatment quality programs for depression are cost-beneficial to purchasers.

Adult↗
PubMed2006

Cardiovascular outcomes in new users of coxibs and nonsteroidal antiinflammatory drugs: high-risk subgroups and time course of risk.

OBJECTIVE: Controversy persists regarding the cardiovascular risks of treatment with selective cyclooxygenase 2 inhibitors (coxibs) and nonselective nonsteroidal antiinflammatory drugs (NSAIDs). This study was undertaken to examine, in a large group of new users of coxibs and NSAIDs, the rate of cardiovascular events, their time course, and whether baseline cardiovascular risk modified the rate ratios (RRs) for future events. METHODS: This cohort study included Medicare beneficiaries who enrolled in a state-run prescription drug plan that fully covered NSAIDs and coxibs without restriction. All study patients started use of a coxib or NSAID after January 1, 1999. The primary composite end point was a hospital admission for either myocardial infarction or ischemic stroke. Predefined exposure groups included the 3 coxibs available in the US during the study period (celecoxib, rofecoxib, and valdecoxib), as well as oral formulations of diclofenac, ibuprofen, naproxen, and a composite of all other NSAIDs. We compared the rate of cardiovascular events associated with each of these agents with that in a reference group of patients who did not use NSAIDs or coxibs, but started other medications unrelated to cardiovascular risk. Daily exposure to all study drugs was assessed based on filled prescription data. A Cox proportional hazards model stratified on calendar year that included other baseline cardiovascular risk factors constituted the primary analysis. RESULTS: We identified 74,838 users of NSAIDs or coxibs, and 23,532 comparable users of other drugs comprised the reference group. Adjusted models demonstrated a significant elevation in the event rate for rofecoxib (RR 1.15, 95% confidence interval [95% CI] 1.06-1.25) and a significant reduction in the rate for naproxen (RR 0.75, 95% CI 0.62-0.92). No other coxib or NSAID was associated with a significant increase or decrease in cardiovascular event rate. The increased rate associated with rofecoxib was seen in the first 60 days of use (adjusted RR 1.14, 95% CI 1.01-1.29) and thereafter (adjusted RR 1.14, 95% CI 1.02-1.28). Kaplan-Meier event curves showed a similar pattern of risk (early and persistent separation of the event curves) among long-term rofecoxib users at low or high baseline cardiovascular risk. CONCLUSION: We found an increased cardiovascular event rate among users of rofecoxib, and a decreased rate with naproxen use. Other coxibs and NSAIDs did not appear to be associated with a difference in event rate compared with users of other drugs. The increase in rate associated with rofecoxib was seen within the first 60 days and persisted. There was no important modification of the event rate based on the patient's baseline cardiovascular risk.

Aged↗
PubMed2006

Tumor necrosis factor alpha antagonist use and cancer in patients with rheumatoid arthritis.

OBJECTIVE: Concerns persist about a possible association between tumor necrosis factor alpha (TNFalpha) antagonist treatment and development of cancers in patients with rheumatoid arthritis (RA). This study was undertaken to estimate the association between treatment with biologic disease-modifying antirheumatic drugs (DMARDs) and development of cancer in patients with RA. METHODS: We conducted a cohort study pooling administrative databases from 2 US states and 1 Canadian province. A cohort of patients who had received a diagnosis of RA on > or =1 occasion and had been prescribed DMARDs was identified. We categorized patients with a prescription for a biologic DMARD as biologic DMARD users, and those with a prescription for methotrexate (MTX) but no biologic DMARD as MTX users. We used time-varying propensity scores to adjust for the large number of possible confounders and stratified proportional hazards regression to estimate the effects of biologic DMARDs on cancer. The primary end points were hematologic malignancies (lymphoma, multiple myeloma, and leukemia) and common solid tumors (colorectal, lung, stomach, breast, prostate, uterine, ovarian, urinary tract/bladder, and melanoma). RESULTS: The pooled cohort included 1,152 biologic DMARD users and 7,306 MTX users. We identified 11 hematologic malignancies and 46 solid tumors during 2,940 person-years of biologic DMARD use, and 88 hematologic malignancies and 558 solid tumors during 30,300 person-years of MTX use. Comparing biologic DMARD users with MTX users, the propensity score-adjusted pooled hazard ratio was 1.37 (95% confidence interval 0.71-2.65) for hematologic malignancies and 0.91 (95% confidence interval 0.65-1.26) for solid tumors. CONCLUSION: Our results indicate that users of biologic agents are unlikely to have a substantial increase in the risk of hematologic malignancies and solid tumors as compared with MTX users. Despite the use of large combined data sets, studying the effect of an infrequent exposure (biologic DMARDs) on rare diseases (hematologic malignancies) remains a challenge.

Aged↗
PubMed2006

Immunosuppressive medications and hospitalization for cardiovascular events in patients with rheumatoid arthritis.

OBJECTIVE: The risk of cardiovascular disease (CVD) is increased in patients with rheumatoid arthritis (RA), most likely because of increased systemic inflammation. Prior research suggests that immunosuppressive medications may reduce the risk of CVD among RA patients. This study was undertaken to investigate the effects of various immunosuppressive medications on the risk of cardiovascular events among a group of older patients with RA. METHODS: In this nested case-control study, the source cohort was derived from Medicare beneficiaries receiving a drug benefit from the state of Pennsylvania. These individuals were required to have been diagnosed as having RA on at least 2 visits and to have filled a prescription for an immunosuppressive agent. Cases were defined as those patients who were hospitalized for a cardiovascular event such as myocardial infarction or stroke, and 10 control subjects were matched to each case by age, sex, and calendar year of the index date (the time of the first cardiovascular event in each case). Current use of an immunosuppressive medication was defined as having filled a prescription for these agents within the 90 days prior to the index date. Multivariate logistic regression models that included important covariates were assessed to determine the risk of cardiovascular events associated with immunosuppressive agents and their combinations. RESULTS: Among the study cohort, we identified 3,501 RA patients who fulfilled our eligibility criteria. During followup of this cohort, 946 patients were hospitalized for a cardiovascular event. Although the 95% confidence intervals (95% CIs) were wide in adjusted risk regression models with methotrexate (MTX) monotherapy as the reference group, biologic immunosuppressive agents showed neither protective nor deleterious effects (with biologics monotherapy, odds ratio [OR] 1.0, 95% CI 0.5-1.9; with biologics plus MTX combination therapy, OR 0.8, 95% CI 0.3-2.0; and with biologics plus other immunosuppressive agents, OR 1.2, 95% CI 0.7-2.2). Monotherapy with oral glucocorticoids was associated with an increased risk of cardiovascular events (OR 1.5, 95% CI 1.1-2.1), and a similar trend in the direction of risk was seen with glucocorticoid combination therapy (OR 1.3, 95% CI 0.8-2.0). Cytotoxic immunosuppressive agents other than MTX (azathioprine, cyclosporine, and leflunomide) were also associated with an increased risk of cardiovascular events (with both monotherapy and combination treatment, OR 1.8, 95% CI 1.1-3.0). CONCLUSION: When compared with RA patients receiving MTX monotherapy, those receiving biologic immunosuppressive agents had neither an increased nor decreased risk of experiencing a cardiovascular event, whereas use of oral glucocorticoids and cytotoxic immunosuppressive agents was associated with significant increases in the risk of cardiovascular events.

Aged, 80 and over↗
PubMed2006

A therapeutic substitution policy for proton pump inhibitors: clinical and economic consequences.

OBJECTIVE: With the growing need to provide prescription drug benefits to older patients and to contain costs, it will be necessary to direct that coverage so as to make expenditures as efficient as possible. We evaluated the clinical and economic consequences of coverage restriction for 3 leading proton pump inhibitors (PPIs) in a large-scale natural experiment. METHODS: The study design was a time-trend analysis in the setting of a provincial drug benefits program in British Columbia, Canada. We studied all British Columbia residents aged 66 or older (N = 501,104) using linked data on all prescription drug dispensings, physician services, and hospitalizations between January 2002 and June 2004. The new policy restricted coverage to rabeprazole and required treatment failure with a histamine H2 blocker. More widely used PPIs (omeprazole, pantoprazole, and lansoprazole) had to be paid for out of pocket, unless the physician requested an exemption. The main outcome measures were utilization of PPIs, drug discontinuation rates, gastrointestinal hemorrhage rates, and drug expenditures. RESULTS: Utilization of the restricted PPIs declined sharply after the policy change (-14,850 daily doses per month per 10,000 residents, P < .0001), whereas use of the covered PPI increased sharply (+19,300, P < .0001), with 45% of all PPI users switching to the covered agent within 6 months. We found no increased use of H2 blockers or stopping of gastroprotective drugs. There was no increase in the monthly rate of hospitalization for gastrointestinal hemorrhage after the PPI restriction (P = .35) even though the study had the power to detect increases of 24 events per 10,000 residents with 95% confidence. There was a slight increase in physician visits 3 months after the policy change (P = .01) for a 2-month period when 9% of new rabeprazole users were switched back to a restricted PPI. In the first 6 months of the policy change, the provincial health plan saved at least 2.9 million Canadian dollars as a result of the policy change. CONCLUSIONS: Coverage restriction of 3 leading PPIs led to substantial utilization changes and savings, without increased noncompliance or clinical complication.

2-Pyridinylmethylsulfinylbenzimidazoles↗