Prevalence and quality of warfarin use for patients with atrial fibrillation in the long-term care setting.

BACKGROUND: Evidence-based clinical practice guidelines recommend the use of warfarin sodium for stroke prevention in most patients with atrial fibrillation (AF) who do not have risk factors for hemorrhagic complications, irrespective of age. METHODS: The medical records of all residents of a convenience sample of long-term care facilities in Connecticut (n = 21) were reviewed. The percentages of all patients with AF (AF patients) and ideal candidates for warfarin therapy (ie, AF patients with no risk factors for hemorrhage) who received warfarin were determined; for patients receiving warfarin, the percentage of days spent in the therapeutic range of international normalized ratio (INR) values (2.0-3.0) was also assessed. The relationship between receipt of warfarin and the presence of stroke and bleeding risk factors was assessed in multivariate models. RESULTS: Atrial fibrillation was present in 429 (17%) of the 2587 long-term care residents. Overall, 42% of AF patients were receiving warfarin. However, only 44 (53%) of 83 ideal candidates were receiving this therapy. In residents who received warfarin therapy, the therapeutic range of INR values was maintained only 51% of the time. The odds of receiving warfarin in the study sample decreased with increasing number of risk factors for bleeding and increased (nonsignificant trend) with increasing number of stroke risk factors present. CONCLUSIONS: Atrial fibrillation is very common among residents of long-term care facilities. Even among apparently ideal candidates, warfarin therapy is underused for stroke prevention in patients with AF. Prescribing decisions and monitoring related to warfarin therapy in the long-term care setting warrant improvement.

The treating physician as active gatekeeper in the recruitment of research subjects.

BACKGROUND: Institutional Review Boards vary in regard to the conditions imposed on investigators concerning contacting potential subjects to participate in health-services research studies. OBJECTIVE: The impact of more active involvement of the treating physician was examined in the approval process for recruiting study subjects. DESIGN: In recruiting subjects for a Massachusetts-based, multihospital (n = 17), health-services research study of treatment patterns for early stage breast cancer that required patient interviews, four hospitals stipulated that the treating surgeon provide written permission to the investigators to allow any contact with a potential study subject for the purpose of recruitment (active physician involvement group); the remaining 13 hospitals stipulated that the treating surgeon need only respond to the investigators if contact with a potential subject was forbidden (passive physician involvement group). SUBJECTS: Of the 1401 potential subjects treated for early stage breast cancer, 697 were in the active physician involvement group and 704 were in the passive physician involvement group. MEASURES: The percentages of patients for whom contact was allowed for recruitment purposes and who enrolled in the study were determined for the active physician involvement group and the passive physician involvement group, respectively. Logistic regression models were used to assess the independent effect of physician involvement on study enrollment. RESULTS: Of the 697 patients in the active physician involvement group, contact was approved by the treating surgeon for 72% (n = 505), compared with 91% (n = 638) of the passive physician involvement group (P <0.001). After adjustment for a variety of patient, physician, and hospital-level variables, patients in the passive physician involvement group were found to be significantly more likely to be enrolled in the study (adjusted OR 2.61; 95% CI, 1.53-4.45). However, among those patients approved for investigator contact, there were no significant differences between patients who were enrolled and patients who were not enrolled in the study with regard to physician involvement in the recruitment process (adjusted OR 1.13; 95% CI, 0.70-1.81). CONCLUSION: Our findings demonstrate that more stringent IRB requirements on health services researchers to verify permission from the treating physician to access patients for recruitment purposes adversely impact on the enrollment of patients even in noninterventional research studies. Current procedures for involving the treating physician as a gatekeeper in the recruitment of research subjects may limit access to patient participation in research studies from the perspectives of both researchers and potential subjects.

Risk factors for adverse drug events among nursing home residents.

BACKGROUND: In a prospective study of nursing home residents, we found adverse drug events (ADEs) to be common, serious, and often preventable. To direct prevention efforts at high-risk residents, information is needed on resident-level risk factors. METHODS: Case-control study nested within a prospective study of ADEs among residents in 18 nursing homes. For each ADE, we randomly selected a control from the same home. Data were abstracted from medical records on functional status, medical conditions, and medication use. RESULTS: Adverse drug events were identified in 410 nursing home residents. Independent risk factors included being a new resident (odds ratio [OR], 2.8; 95% confidence interval [CI], 1.5-5.2) and taking anti-infective medications (OR, 4.0; CI, 2.5-6.2), antipsychotics (OR, 3.2; CI, 2.1-4.9), or antidepressants (OR, 1.5; CI, 1.1-2.3). The number of regularly scheduled medications was associated with increased risk of ADEs; the OR associated with taking 5 to 6 medications was 2.0 (CI, 1.2-3.2); 7 to 8 medications, 2.8 (CI, 1.7-4.7); and 9 or more, 3.3 (CI, 1.9-5.6). Taking supplements or nutrients was associated with lower risk (OR, 0.42; CI, 0.27-0.63). Preventable ADEs occurred in 226 residents. Independent risk factors included taking opioid medications (OR, 6.6; CI, 2.3-19.3), antipsychotics (OR, 4.0; CI, 2.2-7.3), anti-infectives (OR, 3.0; CI, 1.6-5.8), antiepileptics (OR, 2.2; CI, 1.1-4.5), or antidepressants (OR, 2.0; CI, 1.1-3.5). Scores of 5 or higher on the Charlson Comorbidity Index were associated with increased risk of ADEs (OR, 2.6; CI, 1.1-6.0). The number of regularly scheduled medications was also a risk factor: the OR for 7 to 8 medications was 3.2 (CI, 1.4-6.9) and for 9 or more, 2.9 (CI, 1.3-6.8). Residents taking nutrients or supplements were at lower risk (OR, 0.27; CI, 0.14-0.50). CONCLUSIONS: It is possible to identify nursing home residents at high risk of having an ADE. Particular attention should be directed at new residents, those with multiple medical conditions, those taking multiple medications, and those taking psychoactive medications, opioids, or anti-infective drugs.

Influence of physician specialty on adoption and relinquishment of calcium channel blockers and other treatments for myocardial infarction.

OBJECTIVE: Recent reports have linked calcium channel blockers (CCBs) with an increased risk of acute myocardial infarction (AMI). We sought to determine to what extent physicians relinquished CCBs following these adverse reports and if there were differences in the use of CCBs and other AMI therapies across 3 levels of specialist involvement: generalist attendings, collaborative care (generalist with cardiologist consultation), and cardiologist attendings. DESIGN: We measured use of CCBs during hospitalization for AMI before (1992--1993) and after (1995--1996) the adverse CCB reports, controlling for hospital-, physician-, and patient-level variables. We also examined use of effective medications (aspirin, beta-blockers, thrombolytic therapy) and ineffective AMI treatments (lidocaine). SETTING: Thirty-seven community-based hospitals in Minnesota. PATIENTS: Population-based sample of 5,347 patients admitted with AMI. MEASUREMENTS: The primary outcome was prescription of a CCB at the time of discharge from hospital. Secondary outcomes included use of other effective and ineffective AMI therapies during hospitalization and at discharge. MAIN RESULTS: Compared with cardiologists, generalist attendings were less likely to use aspirin (37% vs 68%; adjusted odds ratio [OR], 0.58; 95% confidence interval [95% CI], 0.42 to 0.80) and thrombolytics (29% vs 64%; adjusted OR, 0.18; 95% CI, 0.13 to 0.25), but not beta-blockers (20% vs 46%; adjusted OR, 0.93; 95% CI, 0.66 to 1.31). From 1992--1993 to 1995--1996, the use of CCBs in patients with AMI decreased from 24% to 10%, the net result of physicians starting CCBs less often and discontinuing them more often. In multivariate models, the odds of CCB relinquishment after the adverse reports (adjusted OR, 0.33; 95% CI, 0.27 to 0.39) were independent of, and not modified by, the involvement of a cardiologist. CONCLUSIONS: Compared with cardiologists, generalist physicians were less likely to adopt some effective AMI therapies, particularly those associated with risk such as thrombolytic therapy. However, generalists were as likely as cardiologists to relinquish CCBs after the adverse reports. This pattern of practice may be the generalist physicians' response to an expanding, but increasingly risky and uncertain, pharmacopoeia.

Prevention of glucocorticoid-induced osteoporosis: experience in a managed care setting.

BACKGROUND: Treatment with glucocorticoids is the leading cause of drug-induced osteoporosis. Currently available guidelines indicate that patients receiving long-term glucocorticoid therapy should receive measures to prevent osteoporosis. OBJECTIVES: To examine whether patients receiving long-term glucocorticoid therapy in a managed care setting received preventive therapy or prescribed medications for osteoporosis and to identify patient and provider characteristics associated with treatment. SUBJECTS AND METHODS: A cohort of 224 health plan enrollees 20 years and older who were dispensed at least 1 oral glucocorticoid prescription per quarter during the period October 1997 through September 1998 was identified from administrative data. Medical charts and administrative data were reviewed to determine use of preventive therapy and prescribed medications for osteoporosis. RESULTS: Of the 224 patients, 62% had at least 1 documented intervention aimed at osteoporosis prevention (counseling about calcium or vitamin D or weight-bearing exercise; prescription for estrogen, calcitonin, or bisphosphonate; or a bone mineral density study). Women were more likely than men to receive intervention (76% vs 44%; prevalence odds ratio, 4.41; 95% confidence interval, 2.17-9.10). Patients receiving a mean daily prednisone dose of 10 mg or more or 5 to less than 10 mg were no more likely to receive intervention than those receiving 5 mg or less prednisone daily. Sixty-two (90%) of 69 patients who were prescribed glucocorticoid therapy by rheumatologists had at least 1 intervention documented compared with 29 (48%) of 60 for internists, 26 (55%) of 47 for pulmonologists, and 22 (46%) of 48 for all other physicians. In a multiple logistic regression model, including patient age, sex, mean daily glucocorticoid dose, and physician specialty, women and patients prescribed glucocorticoids by a rheumatologist were significantly more likely to receive intervention aimed at osteoporosis prevention. CONCLUSIONS: A substantial proportion of patients receiving long-term glucocorticoid therapy do not receive preventive therapy for osteoporosis. Efforts should be made to reduce barriers to such treatment and increase the proportion of patients given preventive therapy.

Death or nonfatal stroke in patients with acute myocardial infarction treated with tissue plasminogen activator. Participants in the National Registry of Myocardial Infarction 2.

In a retrospective cohort of patients treated in community hospitals, tissue plasminogen activator (t-PA) was associated with decreased odds of in-hospital death or nonfatal stroke. However, the relative benefit was less evident in older patients and women, and some older subgroups did not benefit from treatment.

Recent magnitude of and temporal trends (1994-1997) in the incidence and hospital death rates of cardiogenic shock complicating acute myocardial infarction: the second national registry of myocardial infarction.

BACKGROUND: Limited recent data are available to describe the magnitude of, and temporal trends in, the incidence and case-fatality rates associated with cardiogenic shock complicating acute myocardial infarction. The purpose of this study was to examine recent (1994-1997) trends in the incidence of, and hospital death rates from, cardiogenic shock complicating acute myocardial infarction from a large, multihospital national perspective. METHODS: An observational study was performed of 426,253 patients hospitalized with acute myocardial infarction in 1662 hospitals throughout the United States between 1994 and 1997. RESULTS: The incidence rates of cardiogenic shock averaged 6.2%. There was evidence for a slight decline in these rates between 1994 (6.6%) and 1997 (6.0%). Results of a multivariable regression analysis controlling for factors that might affect the risk of development of cardiogenic shock indicated that patients hospitalized in more recent years were at significantly lower risk for shock. Patients with shock had a markedly increased risk for dying during hospitalization compared with patients not having shock (74% vs 10%). Significant, albeit small, absolute differences were observed in the risk of dying after cardiogenic shock over time (76% dying in 1997, 72% dying in 1994). These improving trends were magnified, however, after potentially confounding prognostic factors were controlled: patients having shock in 1997 were at approximately one fifth lower risk of dying (odds ratio 0.79, 95% confidence interval 0.71-0.87) than those hospitalized in 1994. CONCLUSIONS: Our findings indicate a slight decline in the incidence rates of cardiogenic shock and improving trends in the hospital survival of patients with shock. Despite these trends, it remains of considerable importance to prevent this clinical syndrome, given its high lethality.

Multicenter epidemiologic and health services research on therapeutics in the HMO Research Network Center for Education and Research on Therapeutics.

Research and education programs in therapeutics that combine the data, organizational capabilities, and expertise of several managed care organizations working in concert can serve an important role when a single organization is not large enough to address a question of interest, when diversity in populations or delivery systems is required, and when it is necessary to establish consistency of results in different settings. Nine members of the HMO Research Network, a consortium of health maintenance organizations (HMOs) that perform public domain research, have formed a Center for Education and Research on Therapeutics (CERT), sponsored by the Agency for Healthcare Research and Quality, to conduct multicenter research in therapeutics. The CERT uses a distributed organizational model with shared leadership, in which data reside at the originating organization until they are needed to support a specific study. Extraction of data from the host computer systems, and some manipulation of data, is typically accomplished through computer programs that are developed centrally, then modified for use at each site. For complex studies, pooled analysis files are created by a coordinating center, and then analysed by investigators throughout the HMOs. It is also possible to contact HMO members when necessary. This multicenter environment has several benefits, addressing: (1) a wide array of questions about the safety and effectiveness of therapeutics, (2) the impact of efforts to change clinicians' and patients' behavior, and (3) pharmacoeconomic and pharmacogenetic questions.

The diffusion of a novel therapy into clinical practice: the case of sildenafil.

BACKGROUND: Erectile dysfunction is a common condition, yet in the past most affected men did not seek medical treatment. OBJECTIVE: To examine how sildenafil (Viagra), a new medication for the treatment of erectile dysfunction, has been incorporated into general medical practice. SUBJECTS AND METHODS: The study population consisted of all male members of a group-model Massachusetts health maintenance organization (HMO) whose first prescription for sildenafil was dispensed during the first 24 weeks of its availability through the HMO as a plan benefit (April 24, 1998, through October 8, 1998). Data collected on each member in the study population included age, specialty of the prescribing physician, initial dose, use of prior treatments for erectile dysfunction, receipt of medications known to predispose to impotence, filling of a second prescription for sildenafil, and concomitant medical conditions (including hypertension, ischemic heart disease, hyperlipidemia, diabetes mellitus, and history of radical prostatectomy). Cross tabulations and logistic regression models were constructed to evaluate the potential associations between filling a second prescription for sildenafil and other characteristics of sildenafil users. RESULTS: We identified 899 members who filled a first-time sildenafil prescription in the 24-week period of interest. The majority of sildenafil prescriptions that were filled for the first time (85%) occurred in the first 12 weeks of its availability. Most sildenafil users (84%) were between 45 and 74 years of age (average age, 61 years; age range, 23 to 90 years), and approximately 40% had documentation of prior treatment for erectile dysfunction. Use was highest among those aged 55 to 64 years, with almost 5% of all male HMO members in that age group having received at least 1 sildenafil prescription. Our cohort of sildenafil users was significantly more likely to have hypertension (P<.01), hyperlipidemia (P<.01), and diabetes mellitus (P<.01) than persons who participated in a widely publicized clinical trial of the medication. Prescribing physicians were predominantly primary care physicians (78% were internists, and 11% were family practitioners). More than 60% of sildenafil users filled a second prescription within 3 months of the first prescription; in multivariate analyses, factors associated with filling a second prescription included younger age and prior treatment for erectile dysfunction. CONCLUSIONS: Sildenafil was rapidly adopted into the clinical practice of primary care physicians for the treatment of erectile dysfunction in the managed care setting. The patients for whom the drug was prescribed in the general practice setting differed across many medical characteristics from study subjects who participated in clinical trials of the drug. Arch Intern Med. 2000;160:3401-3405.

Intracranial hemorrhage rates and effect of immediate beta-blocker use in patients with acute myocardial infarction treated with tissue plasminogen activator. Participants in the National Registry of Myocardial Infarction-2.

In acute myocardial infarction (AMI), immediate beta-blocker therapy reduces the incidence of reinfarction and recurrent chest pain in patients receiving tissue plasminogen activator (t-PA). Data from the Thrombolysis in Myocardial Infarction (TIMI)-2 trial also raises the possibility that such therapy may reduce the rate of intracranial hemorrhage (ICH). We reviewed data obtained from 60,329 patients treated with t-PA who were enrolled in the National Registry of Myocardial Infarction 2. Of the 60,329 in the study cohort, 23,749 patients (39.4%) were treated with immediate beta-blocker therapy and 542 patients (0.9%) developed an ICH. In a multivariate model that included all covariates known to be associated with the development of ICH, immediate beta-blocker therapy was associated with a 31% reduction in the ICH rate (odds ratio 0.69, 95% confidence intervals 0.57 to 0.84). Thus, in the present study, the use of immediate beta-blocker therapy in patients with AMI treated with t-PA was associated with a significant reduction in ICH. This finding supports the observations made in the TIMI 2 trial and serves to reinforce the recommendations made by the American College of Cardiology/American Heart Association task force that immediate beta-blocker therapy should be administered to all patients with AMI who do not have contraindications to this therapy.

Incidence and preventability of adverse drug events in nursing homes.

PURPOSE: Adverse drug events, especially those that may have been preventable, are among the most serious concerns about medication use in nursing homes. We studied the incidence and preventability of adverse drug events and potential adverse drug events in nursing homes. METHODS: We performed a cohort study of all long-term care residents of 18 community-based nursing homes in Massachusetts during a 12-month observation period. Potential drug-related incidents were detected by stimulated self-report by nursing home staff and by periodic review of the records of nursing home residents by trained nurse and pharmacist investigators. Each incident was classified by 2 independent physician-reviewers, using a structured implicit review process, by whether or not it constituted an adverse drug event or potential adverse drug event (those that may have caused harm, but did not because of chance or because they were detected), by the severity of the event (significant, serious, life-threatening, or fatal), and by whether it was preventable. Examples of significant events included nonurticarial rashes, falls without associated fracture, hemorrhage not requiring transfusion or hospitalization, and oversedation; examples of serious events included urticaria, falls with fracture, hemorrhage requiring transfusion or hospitalization, and delirium. RESULTS: During 28,839 nursing home resident-months of observation in the 18 participating nursing homes, 546 adverse drug events (1.89 per 100 resident-months) and 188 potential adverse drug events (0.65 per 100 resident-months) were identified. Of the adverse drug events, 1 was fatal, 31 (6%) were life-threatening, 206 (38%) were serious, and 308 (56%) were significant. Overall, 51% of the adverse drug events were judged to be preventable, including 171 (72%) of the 238 fatal, life-threatening, or serious events and 105 (34%) of the 308 significant events (P < 0.001). Errors resulting in preventable adverse drug events occurred most often at the stages of ordering and monitoring; errors in transcription, dispensing, and administration were less commonly identified. Psychoactive medications (antipsychotics, antidepressants, and sedatives/hypnotics) and anticoagulants were the most common medications associated with preventable adverse drug events. Neuropsychiatric events were the most common types of preventable adverse drug events. CONCLUSIONS: Adverse drug events are common and often preventable in nursing homes. More serious adverse drug events are more likely to be preventable. Prevention strategies should target the ordering and monitoring stages of pharmaceutical care.

Rate of heart failure and 1-year survival for older people receiving low-dose beta-blocker therapy after myocardial infarction.

BACKGROUND: Many older people do not receive beta-blocker therapy after myocardial infarction or receive doses lower than those tested in trials, perhaps because physicians fear that beta-blockers may precipitate heart failure. We examined the relation between use of beta-blockers, the dose used, and hospital admission for heart failure and 1-year survival in a cohort of all older patients surviving myocardial infarction in Ontario, Canada. METHODS: We collected data on a cohort of 13,623 patients aged 66 years or older who were discharged from hospital after a myocardial infarction and who did not receive beta-blocker therapy or received low, standard, or high doses. We used Cox's proportional-hazards models to study the association of dose with admission for heart failure and survival with adjustment for factors including age, sex, and comorbidity. FINDINGS: Among 8232 patients with no previous history of heart failure, dispensing of beta-blocker therapy was associated with a 43% reduction in subsequent admission for heart failure (adjusted risk ratio 0.57 [95% CI 0.48-0.69]) compared with patients not dispensed this therapy. Among the 4681 patients prescribed beta-blockers, the risk of admission was greater in the high-dose than in the low-dose group (1.53 [1.01-2.31]). Among all 13,623 patients in the cohort, 2326 (17.1%) died by 1 year. Compared with those not dispensed beta-blocker therapy, the adjusted risk ratio for mortality was lower for all three doses (low 0.40 [0.34-0.47], standard 0.36 [0.31-0.42], high 0.43 [0.33-0.56]). INTERPRETATION: Compared with high-dose beta-blocker therapy, low-dose treatment is associated with a lower rate of hospital admission for heart failure and has a similar 1-year survival benefit. Our findings support the need for a randomised controlled trial comparing doses of beta-blocker therapy in elderly patients.

Evaluation of a formulary switch from conjugated to esterified estrogens in a managed care setting.

BACKGROUND: Formulary switches between agents in the same therapeutic class have become commonplace in the managed care setting as a strategy to reduce costs. OBJECTIVES: We evaluated the impact of a formulary switch from conjugated to esterified estrogen tablets at the Fallon Community Health Plan, a mixed-model health maintenance organization. DESIGN: A retrospective study was conducted with the use of the automated database of the health plan. SUBJECTS: Study subjects were members of the health plan during the period from May 1, 1995, to December 31, 1997, who were dispensed > or =1 estrogen replacement product. From this population, a cohort of users of conjugated estrogens during the period from May 1, 1995, to October 31, 1995, was selected. MEASURES: The cumulative incidence of switching from conjugated to esterified estrogen tablets and subsequent discontinuations of esterified estrogens was evaluated. The frequencies of ambulatory encounters during the 6 months before and after a switch or discontinuation were compared. RESULTS: During the period after promotion of the formulary switch, 2,149 of 2,984 patients (72%) originally dispensed conjugated estrogen tablets switched to esterified estrogen tablets. Among those patients switching to esterified estrogens, an excess of 20 office visits per 100 patients was noted in the postswitch period (P = 0.005). The risk of switching back to conjugated estrogen tablets was 15% by 2 years. CONCLUSIONS: The findings of this study suggest that plan efforts were successful in switching most users of conjugated estrogens to esterified estrogens. The switch was associated with an increase in utilization of health care services.

Intracranial hemorrhage associated with thrombolytic therapy for elderly patients with acute myocardial infarction: results from the Cooperative Cardiovascular Project.

BACKGROUND AND PURPOSE: Intracranial hemorrhage is a serious complication of thrombolytic therapy for acute myocardial infarction, especially among the elderly, but little information exists on estimating risk. Better estimation of risk in individual patients may allow for withholding or using alternate therapies among those at highest risk. METHODS: To quantify the risk and identify predictors of intracranial hemorrhage associated with thrombolytic therapy, we performed a retrospective cohort study using data from medical charts. The study involved nearly all acute-care hospitals in the United States. All Medicare patients discharged with a principal diagnosis of acute myocardial infarction during a 9-month period in 1994 to 1995 were included. The main outcome measure was intracranial hemorrhage among those treated with thrombolytic therapy. RESULTS: The rate of intracranial hemorrhage was 1.43% (455 of 31 732). In a logistic model, age > or =75 years, female, black race, prior stroke, blood pressure > or =160 mm Hg, tissue plasminogen activator (versus other thrombolytic agent), excessive anticoagulation (international normalized ratio > or =4 or prothrombin time > or =24), and below median weight (< or =65 kg for women; < or =80 kg for men) were independent predictors. A risk stratification scale was developed on the basis of these factors: with none or 1 of the factors (n=6651), the rate of intracranial hemorrhage was 0.69%; with 2 factors (n=10 509), 1.02%; with 3 factors (n=9074), 1.63%; with 4 factors (n=4298), 2.49%; and with > or =5 factors (n=1071), 4. 11% (Mantel-Haenszel; P<0.001). CONCLUSIONS: The rate of intracranial hemorrhage in older patients after treatment with thrombolytic therapy exceeds 1%. Readily available factors can identify elderly patients with acute myocardial infarction at high and low risk for intracranial hemorrhage associated with thrombolytic therapy.

Improving discussion of surgical treatment options for patients with breast cancer: local medical opinion leaders versus audit and performance feedback.

We studied whether a hospital intervention utilizing medical opinion leaders and performance feedback reduced the proportion of women who reported that surgeons did not discuss options prior to surgery for early stage breast cancer. Opinion leaders provided clinical education to their peers using a variety of strategies and were selected for their ability to influence their peers. Performance feedback involved distributing performance reports that contained data on the outcomes of interest as well as on other treatment patterns. Twenty-eight hospitals in Minnesota were randomized to the intervention or to a control group that received performance feedback only. The proportion of patients at intervention hospitals who said that their surgeon did not discuss options decreased significantly (p < 0.001) from 33% to 17%, but a similar decrease was observed among control hospitals. Using medical opinion leaders to intervene in hospitals appeared as effective as performance feedback.

Evaluating the predictive value of osteoarthritis diagnoses in an administrative database.

OBJECTIVE: To assess the positive and negative predictive values of osteoarthritis (OA) diagnoses contained in an administrative database. METHODS: We identified all members (> or =18 years of age) of a Massachusetts health maintenance organization with documentation of at least one health care encounter associated with an OA diagnosis during the period 1994-1996. From this population, we randomly selected 350 subjects. In addition, we randomly selected 250 enrollees (proportionally by the age and sex of the 350 subjects) who did not have a health care encounter associated with an OA diagnosis. Trained nurse reviewers abstracted OA-related clinical, laboratory, and radiologic data from the medical records of both study groups (all but 1 chart was available for review). Pairs of physician reviewers evaluated the abstracted information for both groups of subjects and rated the evidence for the presence of OA according to 3 levels: definite, possible, and unlikely. RESULTS: Among the group of patients with an administrative diagnosis of OA, 215 (62%) were rated as having definite OA, 36 (10%) possible OA, and 98 (28%) unlikely OA, according to information contained in the medical record. The positive predictive value of an OA diagnosis was 62%. In those without an administrative OA diagnosis, 44 (18%) were assigned a rating of definite OA. The negative predictive value of the absence of an administrative OA diagnosis was 78%. CONCLUSION: Use of administrative data in epidemiologic and health services research on OA may lead to both case misclassification and under ascertainment.

Inhibitors of hydroxymethylglutaryl-coenzyme A reductase and risk of fracture among older women.

BACKGROUND: Inhibitors of hydroxymethylglutaryl-coenzyme A reductase (statins) increase new bone formation in rodents and in human cells in vitro. Statin use is associated with increased bone mineral density of the femoral neck. We undertook a population-based case-control study at six health-maintenance organisations in the USA to investigate further the relation between statin use and fracture risk among older women. METHODS: We investigated women aged 60 years or older. Exposure, outcome, and confounder information was obtained from automated claims and pharmacy data from October, 1994, to September, 1997. Cases had an incident diagnosis of non-pathological fracture of the hip, humerus, distal tibia, wrist, or vertebrae between October, 1996, and September, 1997. Controls had no fracture during this period. We excluded women with records of dispensing of drugs to treat osteoporosis. FINDINGS: There were 928 cases and 2747 controls. Compared with women who had no record of statin dispensing during the previous 2 years, women with 13 or more statin dispensings during this period had a decreased risk of non-pathological fracture (odds ratio 0.48 [95% CI 0.27-0.83]) after adjustment for age, number of hospital admissions during the previous year, chronic disease score, and use of non-statin lipid-lowering drugs. No association was found between fracture risk and fewer than 13 dispensings of statins or between fracture risk and use of non-statin lipid-lowering drugs. INTERPRETATION: Statins seem to be protective against non-pathological fracture among older women. These findings are compatible with the hypothesis that statins increase bone mineral density in human beings and thereby decrease the risk of osteoporotic fractures.

Which patients are treated for glaucoma? An observational analysis.

PURPOSE: More than one million patients in the United States are treated for glaucoma, although little is known about the typical clinical characteristics of this group of patients and the type of therapy they receive. This study was conducted to describe the demographic and diagnostic characteristics of patients beginning long-term drug therapy for glaucoma. METHODS: This cross-sectional study included 544 patients beginning topical glaucoma medication regimens who received care at a group model health-maintenance organization (HMO) located in central Massachusetts. The primary medical records of 544 patients beginning topical glaucoma medication between 1987 and 1990 were reviewed to ascertain the presence of three clinical findings: intraocular pressure (IOP) > or = 22 mmHg; optic disc changes including cup-to-disc ratio > or = 0.8, cup-to-disc asymmetry > or = 0.2, or morphologic disc changes consistent with glaucomatous optic neuropathy; and visual field defect consistent with glaucoma. RESULTS: A majority of the 544 patients (86%) were diagnosed as having primary open-angle glaucoma (POAG) by their physicians. Almost half (44.7%) of these patients had only an elevation in IOP without other clinical findings, and 9% met none of the above criteria for glaucoma according to information in the medical record. CONCLUSION: In this setting, most patients who were prescribed drug therapy for POAG were treated for an elevation in IOP alone in the absence of other ophthalmologic characteristics of glaucoma.