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Essy Mozaffari

Publications and source records attributed to Essy Mozaffari.

At least 19 recordsLinked to original sources

Persistence and adherence with topical glaucoma therapy.

PURPOSE: The present study describes the patterns and predictors of treatment persistence and adherence among patients who are diagnosed with glaucoma or as glaucoma suspects (based on claims codes). DESIGN: A retrospective cohort study using health insurance claims data. METHODS: Newly treated individuals with diagnosed glaucoma (n = 3623) and suspect glaucoma (n = 1677) were obtained from healthcare claims data in the Ingenix Research Database. For each of these two diagnostic groups, we calculated the duration of continuous treatment with the initially prescribed medication (persistence) and the prevalence of use of the initial medication at various time points (adherence). Four drug classes were included: beta-blockers, alpha-agonists, carbonic anhydrase inhibitors, and prostaglandin analogs. RESULTS: Nearly one half of the individuals who had filled a glaucoma prescription discontinued all topical ocular hypotensive therapy within six months, and just 37% of these individuals recently had refilled their initial medication at three years after the first dispensing. Prostaglandins were associated with better persistence than any other drug class, which was indicated by hazard ratios for discontinuation of prostaglandins compared with beta-blockers of 0.40 (95% confidence interval, 0.35-0.44) for diagnosed patients and 0.44 (95% confidence interval, 0.37-0.52) for patients with suspect glaucoma. Prostaglandins showed a similar advantage in adherence. Furthermore, patients with diagnosed glaucoma were more likely to adhere to therapy than patients with suspect glaucoma (relative risk = 1.11; 95% confidence interval, 1.05-1.18). CONCLUSION: Persistence and adherence were substantially better with prostaglandins than with other drug classes, and patients with diagnosed open-angle glaucoma were more likely to adhere to treatment than suspected glaucoma.

Administration, Topical↗

Variations in treatment among adult-onset open-angle glaucoma patients.

OBJECTIVE: To determine the predictors of treatment for glaucoma and suspect glaucoma in a nationally representative sample of diagnosed persons. DESIGN: Retrospective cohort study of persons enrolled in a large managed care organization. PARTICIPANTS: Thirty-five thousand seven hundred fifty-four diagnosed suspects, 5265 diagnosed glaucoma persons, and 2633 individuals coded as having cupping of the optic disc. METHODS: Linked pharmacy and patient care information were used to examine the predictors of initiating glaucoma treatment in this cohort of persons insured by a single managed care organization. Predictors entered into logistic regression models included diagnostic group (suspect vs. diagnosed), age group, gender, region of the country, provider type at the initial visit (optometrist or ophthalmologist), diagnosis index date divided into 2 periods (1995-1998 and 1999-2001), and health plan enrollment duration after the initial diagnosis. MAIN OUTCOME MEASURES: Occurrence of and factors associated with treatment for glaucoma (argon laser trabeculoplasty [ALT], surgery, or topical ocular hypotensives). RESULTS: A logistic regression model adjusting for glaucoma status, age, region, clinician seen at initial visit, and index date found that women were less likely to undergo treatment (topical ocular hypotensives, ALT, or surgery) than men (odds ratio, 0.76; 95% confidence interval, 0.71-0.80). Factors other than gender that were associated with greater likelihood of treatment were glaucoma diagnosis, older age, region, and longer follow-up. CONCLUSIONS: We have documented wide variation in treatment among individuals diagnosed as having glaucoma or as glaucoma suspects. Women were 24% less likely to be treated than men, and younger individuals were far less likely to be treated than older ones. Furthermore, treatment varied by region of the country. Understanding the sources of these variations will help in determining how to arrive at better management strategies for individuals with glaucoma and suspect glaucoma.

Adult↗

Glaucoma management among individuals enrolled in a single comprehensive insurance plan.

OBJECTIVE: To determine the management patterns for glaucoma and suspect glaucoma in a nationally representative sample of newly treated persons. DESIGN: Retrospective cohort study of persons enrolled in a large managed care organization. PARTICIPANTS: One thousand seven hundred twelve diagnosed suspects and 3623 diagnosed glaucoma patients. METHODS: Linked pharmacy and patient care data were used to examine the glaucoma management and treatment patterns in this cohort of persons insured by a single managed care organization. Rates of monitoring and treatment were calculated for the 3 study groups. MAIN OUTCOME MEASURES: Probability of monitoring (return visits, visual fields [VFs], and optic nerve head imaging or photography) and treatment (argon laser trabeculoplasty [ALT] and surgery) for newly treated persons with suspect and glaucoma diagnoses. RESULTS: After a median follow-up of 440 days, 83% of treated diagnosed suspects had had a billed follow-up office visit to either an optometrist or an ophthalmologist at any time during follow-up, 46% had had at least one billed VF, and 13% had had some form of optic nerve head imaging. Rates were slightly higher for those with diagnosed glaucoma (P>0.05). Surgery and ALT were performed rarely in this treated population (1%-6% at 2 years). CONCLUSIONS: This study suggests that a large proportion of individuals felt to require treatment for glaucoma or suspect glaucoma are falling out of care and are being monitored at rates lower than expected from recommendations of published guidelines. More research is needed to confirm these findings and to determine the reasons for loss to follow-up and low monitoring rates.

Adult↗

Management of hypertension and hypercholesterolaemia in primary care in The Netherlands.

OBJECTIVE: Screening, treatment and monitoring guidelines for hypertension and hypercholesterolaemia have been developed to assist physicians in providing evidence-based health care. We conducted a retrospective study to assess the management of patients with these single or combined conditions. RESEARCH DESIGN AND METHODS: This was a retrospective cohort study conducted using data from the Integrated Primary Care Information (IPCI) project based in The Netherlands. Management of hypertension and hypercholesterolaemia was assessed from 2000-2003 by measuring the numbers of patients screened for these conditions, treated pharmacologically and monitored for treatment success. RESULTS: Approximately 11%, 3% and 10% of participants were eligible for screening for hypertension alone, hypercholesterolaemia alone and both conditions, respectively. Blood pressure screening was high in patients eligible for both blood pressure and cholesterol screening (> 86%), whereas cholesterol screening was low (< 56%). Among patients newly identified with hypertension or hypercholesterolaemia who were eligible for pharmacotherapy, 29% and 43% respectively were not treated within one year of diagnosis. Undertreatment was significantly lower in patients with both conditions (24% and 37% for antihypertensive and lipid-lowering treatment, respectively and 28% were not treated for both). Among newly treated patients, in the first year of treatment there was no record of a blood pressure or cholesterol assessment, for 35% and 72%, respectively. CONCLUSION: Management was sub-optimal in patients with hypertension or hypercholesterolaemia as well as in those with both of these conditions. The results of this study are likely to be widely applicable, particularly to other European and industrialised countries that have similar free-access health care systems to The Netherlands.

Adolescent↗

Observed time between prescription refills for newer ocular hypotensive agents: the effect of bottle size.

PURPOSE: To describe prescription refill patterns of ocular hypotensive therapies and to measure differences among refill rates across bottle sizes. DESIGN: Retrospective, population-based, cohort study. METHODS: This study included patients dispensed bimatoprost, brimonidine, dorzolamide/timolol, latanoprost, timolol gel (XE) 0.5%, or travoprost between January 1, 1996, and March 30, 2002. The initial fill date was identified for the cohort-defining ocular hypotensive, and the number of days between each subsequent refill was calculated. The analysis was repeated in patients with at least four refills to evaluate potential bias. Descriptive and survival analyses evaluated differences in refill rates across bottle sizes. RESULTS: In the 27,387 patients contributing up to four evaluable refill sequences, the amount of drug contained in bottles did not predict the number of days between fills. Patients dispensed larger bottles typically refilled sooner than drop-count studies would predict; results for patients with at least four refills (n = 12,976) confirmed these findings. Survival analysis demonstrated that the bottle size trend held across classes of therapy. Compared with 5.0-ml bottles, patients dispensed 10.0-ml and 15.0-ml bottles returned for refills at approximately 1.5 times the expected rate. When average wholesale prices were applied to refill intervals for selected agents, a 45% excess cost per month was found for the larger bottle sizes (10.0 ml vs 5.0 ml or 5.0 ml vs 2.5 ml). CONCLUSIONS: Expected refill patterns predicted by bottle size and mean number of drops do not reflect observed refill patterns. Patients dispensed larger bottle sizes return for refills much sooner than expected, regardless of the class of therapy.

Aged↗

Persistency with latanoprost or timolol in primary open-angle glaucoma suspects.

PURPOSE: To evaluate persistency of pharmacotherapy in primary open-angle glaucoma suspects (glaucoma suspects) treated with latanoprost and timolol. DESIGN: Retrospective, cohort study using the Protocare Sciences managed care database; approximately 3 million members in commercial health maintenance organizations and preferred provider organizations and in Medicare risk plans. METHODS: Patients 20 years of age or older beginning therapy between January 1, 1997, and June 30, 2002, with latanoprost or timolol monotherapy were included. Patients must have been continuously enrolled and not undergone glaucoma surgery in the year preceding the index prescription fill and had glaucoma suspect diagnoses before and after the index date. Prescription refill records for all ocular hypotensives were extracted through June 30, 2002. The two outcome measures were (1) discontinuation of index drug, and (2) either discontinuation or change in index drug. Changing therapy was defined as switching to or adding another ocular hypotensive. Rates of discontinuation and discontinuation/change were compared using Cox regression models. RESULTS: In all, 1,474 patients met the inclusion criteria. Latanoprost was prescribed for 583 patients (40%) and timolol for 891 (60%). Compared with latanoprost, those treated with timolol were 39% more likely to discontinue and 27% more likely to discontinue/change therapy (P <.001 for both comparisons). At 12 months, 39% of patients receiving latanoprost and 25% of those treated with timolol had not discontinued therapy; no discontinuation or change in therapy was seen in 30% and 18%, respectively. CONCLUSIONS: Latanoprost-treated glaucoma suspects demonstrated significantly greater persistency than did patients treated with timolol. The reasons for this difference and its impact on intraocular pressure control and disease progression require further research.

Adult↗

Patient persistency with topical ocular hypotensive therapy in a managed care population.

PURPOSE: To evaluate persistency with topical ocular hypotensive therapies in patients new to pharmacological management of elevated intraocular pressure (IOP). DESIGN: Retrospective, cohort study; Protocare Sciences managed care database; approximately 3 million members in commercial health maintenance organizations and preferred provider organizations and in Medicare risk plans. METHODS: Patients were at least 20 years of age initiating therapy between July 1, 1996, and June 30, 2002, with betaxolol, bimatoprost, brimonidine, dorzolamide, latanoprost, timolol, or travoprost as monotherapy. Patients must have been continuously enrolled and not have received glaucoma surgery in the 180 days before the index prescription fill. Prescription refill records for all ocular hypotensive drugs were extracted through June 30, 2002. Outcome measures were (1) discontinuation of index drug, and (2) either discontinuation or change in index drug. Changing therapy was defined as switching to or adding another ocular hypotensive. Rates of discontinuation and discontinuation/change were compared using Cox regression models. RESULTS: In all, 28,741 patients met the inclusion criteria. Compared with latanoprost, those treated with other drugs were from 37% (timolol) to 72% (bimatoprost) more likely to discontinue and from 20% (timolol) to 58% (dorzolamide) more likely to discontinue/change therapy (P <.001 for all comparisons). At 12 months, 33% of patients treated with latanoprost and 19% of those receiving other ocular hypotensives had not discontinued therapy; 23% and 13%, respectively, had not discontinued or changed therapy. Compared with latanoprost, significantly higher percentages of patients treated with each alternate agent had only one fill of their index drugs (P <.001). CONCLUSIONS: Although persistency rates were low across agents, latanoprost-treated patients demonstrated significantly greater persistency than did those treated with other topical ocular hypotensive therapies.

Administration, Topical↗

An economic evaluation of a European cohort from a multinational trial of linezolid versus teicoplanin in serious Gram-positive bacterial infections: the importance of treatment setting in evaluating treatment effects.

In a recent multinational trial, hospital resource use and total cost of treatment were compared between linezolid and teicoplanin for severe Gram-positive bacterial infections among 227 European hospitalised patients. The results show that the linezolid group had a 3.2-day (6.3 for linezolid versus 9.5 for teicoplanin groups) shorter mean intravenous antibiotic treatment duration. Certain baseline variables, particularly the inpatient location at enrolment and the presence of outpatient/home parenteral antibiotic therapy (OHPAT), had substantial effects on length of stay (LOS) and cost of treatment. After adjusting for the between-treatment difference in these two variables and other baseline variables, the results showed non-significant shorter LOS and lower mean total cost of treatment for the linezolid group among patients with no access to OHPAT.

Acetamides↗

Reference group choice and antibiotic resistance outcomes.

Two types of cohort studies examining patients infected with methicillin-resistant Staphylococcus aureus (MRSA) and vancomycin-resistant enterococci (VRE) were contrasted, using different reference groups. Cases were compared to uninfected patients and patients infected with the corresponding, susceptible organism. VRE and MRSA were associated with adverse outcomes. The effect was greater when uninfected control patients were used.

Cohort Studies↗

A new measure of patient satisfaction with ocular hypotensive medications: the Treatment Satisfaction Survey for Intraocular Pressure (TSS-IOP).

PURPOSE: To validate the treatment-specific Treatment Satisfaction Survey for Intraocular Pressure (TSS-IOP). METHODS: Item content was developed by 4 heterogeneous patient focus groups (n = 32). Instrument validation involved 250 patients on ocular hypotensive medications recruited from ophthalmology practices in the Southern USA. Participants responded to demographic and test questions during a clinic visit. Standard psychometric analyses were performed on the resulting data. SAMPLE: Of the 412 patients screened, 253 consented to participate, and 250 provided complete datasets. The sample included 44% male (n = 109), 44% Black (n = 109) and 57% brown eyed (n = 142) participants, with a mean age of 64.6 years (SD 13.1) and a history of elevated IOP for an average of 8.4 yrs (SD 7.8). A majority was receiving monotherapy (60%, n = 151). RESULTS: A PC Factor analysis (w/ varimax rotation) of the 31 items yielded 5 factors (Eigenvalues > 1.0) explaining 70% of the total variance. Weaker and conceptually redundant items were removed and the remaining 15 items reanalyzed. The satisfaction factors were; Eye Irritation (EI; 4 items), Convenience of Use (CofU; 3 items), Ease of Use (EofU; 3 items), Hyperemia (HYP; 3 items), and Medication Effectiveness (EFF; 2 items). Chronbach's Alphas ranged from.80 to.86. Greater distributional skew was found for less common experiences (i.e., HYP & EI with 65% & 48.4% ceilings) than for more common experiences (i.e., EofU, CofU, EFF with 10.8%, 20.8% & 15.9% ceilings). TSS-IOP scales converged with conceptually related scales on a previously validated measure of treatment satisfaction, the TSQM (r =.36 to.77). Evidence of concurrent criterion-related validity was found. Patients' symptomatic ratings of eye irritation, hyperemia and difficulties using the medication correlated with satisfaction on these dimensions (r =.30-.56, all p <.001). Clinicians' ratings of IOP control, severity of side effects and problematic medication use correlated with patients' satisfaction scores on these dimensions (r =.13-.26, all p <.01). CONCLUSIONS: This study provides initial evidence that the TSS-IOP is a reliable and valid measure, assessing patients' satisfaction with ocular hypotensive medications.

Adult↗

Patient persistency with ocular prostaglandin therapy: a population-based, retrospective study.

BACKGROUND: Open-angle glaucoma affects an estimated 33 million individuals worldwide. An intraocular pressure >21 mm Hg in individuals with no evidence of optic nerve damage is termed ocular hypertension, a risk factor for glaucoma that has been estimated to affect as many as 10% of individuals 40 years of age or older. OBJECTIVE: The purpose of this research was to assess persistency (time on therapy) with prostaglandin analogues in the treatment of glaucoma or ocular hypertension. METHODS: This population-based, retrospective cohort study used the Protocare Sciences managed care database, which includes prescription and medical claims data from multiple managed care organizations. Patients 20 years of age or older who initiated therapy with latanoprost, bimatoprost, or travoprost (index drugs) between April 2001 and June 2002 were included. Patients were required to be continuously enrolled in the same plan for the 180 days preceding index prescription fill. Follow-up continued through June 30, 2002. Two outcome measures were analyzed: (1) discontinuation of the index prostaglandin and (2) either discontinuation or change in the index prostaglandin regimen. Changing therapy was defined as switching to or adding another ocular hypotensive agent. Cox regression models were used to compare rate ratios of discontinuation and discontinuation/change. Patient data were censored on termination of insurance coverage or at the end of the study period. RESULTS: Overall, 7527 patients were prescribed a prostaglandin analogue; 4356 patients met the inclusion criteria (n = 2376, 993, and 987 for latanoprost, bimatoprost, and travoprost, respectively). A total of 58% of patients were women, and 74% were 65 years of age or older. Compared with latanoprost, those treated with bimatoprost were 38% more likely to discontinue and 31% more likely to discontinue/change therapy, and patients treated with travoprost were 36% more likely to discontinue and 29% more likely to discontinue/change therapy (P < 0.001 for each comparison). CONCLUSION: Latanoprost-treated patients demonstrated significantly (P < 0.001) greater persistency than did those treated with either bimatoprost or travoprost.

Administration, Topical↗

Hospital resource use and cost of treatment with linezolid versus teicoplanin for treatment of serious gram-positive bacterial infections among hospitalized patients from South America and Mexico: results from a multicenter trial.

BACKGROUND: Linezolid is a novel oxazolidinone antibiotic that is effective for the treatment of gram-positive bacterial infections. The oral formulation has the potential to reduce length of stay (LOS) when used as a substitute for parenteral glycopeptide antibiotics. In a recent multinational trial comparing linezolid (i.v. followed by oral administration) with teicoplanin (i.v. alone or switched to i.m. administration), linezolid was found to have better efficacy (P = 0.005) and similar safety for treating serious gram-positive infections. OBJECTIVE: The purpose of this study was to compare hospital resource use (primarily LOS) and cost of treatment between linezolid and teicoplanin for hospitalized patients with serious gram-positive infections in South America and Mexico using data from the multinational trial. METHODS: In a multinational, Phase IIIb, open-label, comparator-controlled trial, data were collected from hospitalized patients in centers in 6 South America can countries and Mexico with suspected or confirmed serious gram-positive infections. Patients were randomly assigned to receive i.v. linezolid 600 mg BID (for the entire treatment period [7-28 days] or switched to oral linezolid 600 mg BID) or i.v. teicoplanin (for the entire treatment period or switched to i.m. teicoplanin) dosed per approved prescription information. Data on direct medical resource utilization were collected for each patient, including duration and doses of study medication, location of hospitalization and LOS, comedications, tests and procedures, and outpatient service usage. Unit costs for the medical resources were obtained from secondary sources. RESULTS: A total of 203 patients (97 treated with linezolid and 106 treated with teicoplanin) were enrolled from these 7 countries. The unadjusted results showed that compared with teicoplanin, patients treated with linezolid had a 3.1-day shorter mean i.v. antibiotic treatment duration (P < 0.001), a 2.0- to 2.2-day shorter median and mean LOS (P = 0.03), and a 311 US dollars lower mean total cost of treatment (P = NS). After controlling for age, race, sex, site of infection, inpatient location when the antibiotic treatment started, number of historical and current comorbidities, and whether the patient had a diagnosis of systemic inflammatory response syndrome or sepsis, the multivariate adjusted results were similar to the unadjusted results. The linezolid group had a 1.6-day shorter adjusted LOS or 66% greater odds of early discharge (P = 0.049) and a 335 US dollars lower adjusted mean total cost of treatment (P = NS). CONCLUSION: Linezolid was associated with shorter LOS and duration of IV antibiotic treatment than teicoplanin for serious gram-positive infections in the population studied. Linezolid therapy has the potential to reduce the total cost of treatment.

Acetamides↗

Health care resource utilization associated with treatment of penicillin-susceptible and -nonsusceptible isolates of Streptococcus pneumoniae.

Despite failure to correlate in vitro susceptibility with clinical outcomes for respiratory tract infections and bacteremia, resistance affects management of patients with pneumococcal infections. The economic impact of resistance among pneumococci has not been evaluated. We conducted a single-center, retrospective, observational, cohort study of hospitalized patients infected with Streptococcus pneumoniae isolated from blood or a respiratory source between January 1, 1995, and December 31, 1998. Data were collected for 36 days surrounding the day that the first positive culture was collected. Patients were grouped according to isolate penicillin-susceptibility profile [susceptible minimum inhibitory concentration (MIC) < or = 0.06 microg/ml, nonsusceptible MIC > or = 0.125 microg/ml), and data were analyzed with respect to health care resource utilization patterns. Of 231 patients identified, 142 and 89 had susceptible and nonsusceptible isolates, respectively. Groups were similar with respect to demographics and comorbidities, except that patients infected with a nonsusceptible isolate were more likely to have the isolate obtained from a respiratory source and to have a history of recent antibiotic therapy. No difference was noted with respect to clinical outcome; however, patients infected with a nonsusceptible isolate had a longer median stay (14 vs 10 days, p<0.05). They also had significantly higher total median costs (1600 dollars, 95% confidence interval 257-2943 dollars) due to room and nursing services. Infections caused by penicillin-nonsusceptible pneumococci were not associated with a worse outcome in hospitalized patients but were associated with increased cost of care.

Adult↗

Health and economic outcomes of vancomycin-resistant enterococci.

BACKGROUND: The health and economic impact of vancomycin-resistant enterococci has not been quantified. METHODS: A retrospective matched cohort study was conducted comparing the outcomes of patients with vancomycin-resistant enterococci (cases) with those of control subjects matched for length of hospital stay until inclusion in the cohort, hospital location, and calendar date. The propensity to be a vancomycin-resistant enterococci case was modeled based on patient characteristics, and included in multivariable models to adjust for confounding. Analyses included the following: (1) conditional logistic regression for mortality, surgery, intensive care unit admission, and discharge to long-term care; (2) linear regression for the logarithm of cost; and (3) accelerated failure time model for length of stay. RESULTS: A total of 233 cases were compared with 647 controls. Groups were similar in age (mean, 62 years), sex (female, 47%), and length of stay before inclusion in the cohort (mean, 8.1 days), but differed in primary diagnosis and comorbidities, past infection or colonization with methicillin sodium-resistant Staphylococcus aureus or Clostridium difficile, and treatment with cephalosporins or metronidazole. These variables were included in the propensity score, which had good to excellent prediction. Outcomes for cases vs controls and adjusted risks (relative risks [RRs]) were as follows: (1) case fatality rate, 17% vs 6% (RR, 2.13; P =.04); (2) length of stay after inclusion in the cohort, 15.1 vs 8.5 days (RR, 1.73; P<.001); (3) hospital costs, $52 449 vs $31 915 (RR, 1.40; P<.001); (4) surgery after inclusion in the cohort, 18% vs 10% (RR, 2.74; P =.001); (5) intensive care unit admission after inclusion in the cohort, 25% vs 14% (RR, 3.47; P<.001); and (6) transfer to an institution, 51% vs 35% (RR, 2.01; P =.001). CONCLUSION: Compared with a matched hospital population, a population with vancomycin-resistant enterococci was associated with severe adverse outcomes: increased mortality, morbidity, and costs.

Cohort Studies↗

Use of insurance claims data to assess outpatient antimicrobial therapy for gram-positive infections.

With the increasing frequency of antibiotic-resistant gram-positive infections in the United States, many patients are being treated outside the hospital setting. The majority of studies on the cost of outpatient antimicrobial therapy involve retrospective medical record review or prospective data collection. These methods tend to be expensive and time consuming, and often fail to produce a sufficiently large sample size. Analysis of insurance claims data offers a convenient approach for studying the costs associated with outpatient therapy for gram-positive infections. To demonstrate this approach, a study of the cost of intravenous vancomycin home care therapy was conducted using claims data from a large insurance company.

Adolescent↗

Cost perspectives for outpatient intravenous antimicrobial therapy.

Intravenous antimicrobial therapy often continues after a patient is discharged from the hospital or it begins in the outpatient setting. Reimbursement for this therapy varies by payer. The United States Outpatient Parenteral Antibiotic Therapy (OPAT) Outcomes Registry is a valuable resource for quantifying cost by payer, as well as for describing practice patterns and adverse events related to intravenous antimicrobial therapy. To describe the reimbursement structure and cost of intravenous vancomycin home care therapy for four different types of payers, a survey of home infusion companies was done. Also surveyed were infusion programs participating in the OPAT Outcomes Registry, representing four different types of payers, to determine the cost of outpatient intravenous therapy. A retrospective cohort study of these infusion programs was conducted to describe practice patterns and to identify adverse events that resulted from intravenous vancomycin. We found that the cost of outpatient therapy was substantial, although nonuniform, across payer types. Alternative outpatient therapies associated with lower risks for adverse events and lower costs should be considered.

Anti-Bacterial Agents↗

Measuring patient persistency with drug therapy using methods for the design and analysis of natural history studies.

The same methodologic rigor should be applied in measuring both patient persistency with drug therapy and the natural history of disease: Investigators should design natural history cohort studies and evaluate the resulting data using survival analysis. Although simpler analyses, such as those based on the medication possession ratio, may allow identification of obvious drug therapy patterns, results of survival analyses allow more refined interpretations that may help decision makers improve disease management in the population-based setting. This paper explains how to design persistency studies as natural history studies whose outcomes can be analyzed using survival analysis.

Cohort Studies↗

Population-based persistency rates for topical glaucoma medications measured with pharmacy claims data.

BACKGROUND: Persistency with drug therapy reflects a number of factors, including patient tolerability of adverse events resulting from therapy and clinician satisfaction with the medication's effectiveness in reducing intraocular pressure. OBJECTIVE: This study assesses persistency with topical glaucoma medications administered as initial therapy by evaluating rates of discontinuation and change in therapy. METHODS: A retrospective cohort study was conducted using pharmacy claims data from 3 geographically diverse healthcare plans. Newly treated glaucoma patients younger than 65 years of age were selected based on an initial glaucoma medication fill during a 12-month period. Patients were followed for persistency, defined as discontinuation or change (switch or add-on) of initial glaucoma therapy; discontinuation of therapy was also evaluated as a separate end point. RESULTS: In all, 1330 patients (followed for 1126 person-years) met the eligibility criteria. Compared with latanoprost users, patients initiated on other topical monotherapies were more likely to discontinue or change therapy, and patients initiated on other topical monotherapies were more likely than latanoprost users to discontinue therapy. CONCLUSION: Population-based data indicate that latanoprost offers superior persistency compared to agents from other popular classes of topical ocular hypotensives.

Administration, Topical↗