Impact of Statin Use on Outcomes After Coronary Artery Bypass Graft Surgery

Background— The benefits of statins have been demonstrated for patients with a remote history of coronary artery bypass grafting (CABG); however, no investigation to date has evaluated whether initiation of statin therapy in the early months after surgery improves clinical outcomes.

Methods and Results— A retrospective cohort of 7503 Medicare patients ≥65 years of age who underwent CABG (1995–2003) was assembled by use of linked hospital and pharmacy claims data. Rates of all-cause mortality and major adverse cardiovascular events were compared between patients who were (n=1745) and were not (n=5788) prescribed statins within 1 month of CABG discharge. Additional analyses evaluated the impact of statin initiation between 1 and 6 months after surgery. Multivariable and propensity score analysis demonstrated that statin use within 1 month of CABG discharge independently reduced the risk of all-cause mortality (adjusted hazard ratio 0.82, 95% confidence interval 0.72 to 0.94) compared with no statin use. Similarly, statin use within 1 month of CABG discharge independently reduced the risk of major adverse cardiovascular events (adjusted hazard ratio 0.89, 95% confidence interval 0.81 to 0.98). Initiation of statin therapy between 1 and 6 months after CABG discharge was also associated with reductions in major adverse cardiovascular events and mortality; however, outcome rates between early (≤1 month after CABG) and delayed (1 to 6 months after CABG) statin initiation were not significantly different.

Conclusions— Statin therapy initiated in the early months after hospital discharge independently reduces all-cause mortality and major adverse cardiovascular events after CABG. These findings validate the widespread practice of prescribing long-term statin therapy after CABG.

Comparison of the Impact of the Atrial Fibrillation Follow-Up Investigation of Rhythm Management Trial on Prescribing Patterns: A Time-Series Analysis

Background:

The AFFIRM (Atrial Fibrillation Follow-Up Investigation of Rhythm Management) trial demonstrated that rate control and rhythm control strategies result in similar survival and quality of life for patients with atrial fibrillation (AF). Because of superior safety and lower cost, rate control is now the recommended strategy (or the management of most elderly, high-risk AF patients.

Objective:

To determine the extent to which the AFFIRM trial results have been adopted into actual practice.

Methods:

We conducted a time-series analysis of 3 population-based cohorts of patients with AF who were 66 years of age or older in Pennsylvania and Ontario. We stratified patients in Ontario by socioeconomic status (SES) and examined changes in quarterly prescription rates for rate control and rhythm controlling medications as well as cardioversion procedures before and after publication of the AFFIRM trial.

Results:

The publication of the AFFIRM trial resulted in statistically significant reductions in the use of rhythm controlling medications in all 3 cohorts (p < 0.01). The magnitude of these changes in the non-low SES Canadian cohort was approximately 1% per quarter and was greater than the magnitude observed in the other cohorts (p < 0.001). The use of cardioversion procedures also decreased in all study regions (p < 0.01). In contrast, AFFIRM publication was also associated with a small increase in the use of rate controlling medications in Canada (p < 0.01) but not in the US (p = 0.23).

Conclusions:

Publication of the AFFIRM trial resulted in small but statistically significant changes in the care of patients with AF.

Associations of kidney function with cardiovascular medication use after myocardial infarction

BACKGROUND AND OBJECTIVES

It is unknown whether adherence to recommended medications after myocardial infarction (MI) differs by kidney function.

DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS

This was a retrospective cohort study of older patients who were discharged after MI in two Eastern states between 1995 and 2004. Patients were categorized as having ESRD, having chronic kidney disease (CKD), and being free from diagnosed CKD. Use of angiotensin-converting enzyme inhibitors or angiotensin receptor blockers (ACEI/ARB), beta blockers (BB), and statins was assessed within 30 d after discharge. Good adherence was defined as proportion of days covered >80% during the first year after discharge.

RESULTS

Compared with patients with no CKD, patients with CKD had 22% lower adjusted use of ACEI/ARB but similar rates of BB and statin use. Patients with ESRD experienced 43% lower ACEI/ARB and 17% lower statin use. Only 64% (BB), 57% (statins), and 54% (ACEI/ARB) of patients had good 1-yr adherence. Adherence was similar between patients with CKD and with no CKD for all study drugs. Fewer patients with ESRD had good adherence to BB.

CONCLUSIONS

With the exception of lower ACEI/ARB use in patients with CKD, we found no differences between patients with CKD and with no CKD in their use of and adherence to these cardiovascular medications after MI. Patients with ESRD experienced lower use of ACEI/ARB and statins and lower adherence to BB regimens. Postulated differences in medication use after MI across levels of kidney function are unlikely to explain the observed differences in long-term outcomes.

The economic consequences of non-evidence-based clopidogrel use

BACKGROUND

Clinical trials have helped clarify the efficacy of clopidogrel for the treatment and prevention of vascular disease. Costs for its use exceeded $5.9 billion in 2005, making it the second greatest source of drug expenditure in the world. However, little is known about the appropriateness of that use. Overuse of clopidogrel could have important implications for health care quality and drug expenditures.

METHODS

We conducted a retrospective cohort study linking all filled prescriptions to all clinical encounter data for Medicare beneficiaries enrolled in a large state-wide pharmacy assistance program. We identified all patients newly prescribed clopidogrel during a recent 2-year period and determined the proportion who had indications for clopidogrel, the mean number of tablets filled by patients with and without apparent indications in the year after starting therapy, and the costs associated with the observed patterns of clopidogrel use.

RESULTS

We identified 4977 patients who were newly prescribed clopidogrel. Of these patients, only 47% had > or = 1 documented indications for clopidogrel according to clinical trial findings. Using looser criteria, the number of patients with appropriate indications was 56%. During the first year of therapy, 43% ($2.05 million) of total clopidogrel expenditures for the patients studied was spent on patients without an indication that this agent was required, using the extended criteria for evidence-based use.

CONCLUSIONS

More than 40% of the clopidogrel used in this population appears to have been prescribed to patients for whom the drug had no documented advantage over aspirin or no antiplatelet therapy. If the same proportion applies nationally, in 2005, it would represent almost $1.5 billion of potentially unnecessary health care expenditure.

Trends in drug prescribing for osteoporosis after hip fracture, 1995-2004

OBJECTIVE

To examine trends in osteoporosis drug prescribing after hip fracture from 1995 to 2004.

METHODS

We conducted a population-based study of enrollees in the Pennsylvania Pharmaceutical Assistance Contract for the Elderly. Hip fractures were identified using Medicare hospital claims between January 1, 1995, and June 30, 2004. Osteoporosis treatment comprised oral bisphosphonates, calcitonin, hormone therapy, raloxifene, and/or teriparatide. Kaplan-Meier methods were used to estimate the probability of treatment within 6 months of fracture, censoring patients on their date of death or 6 months postfracture.

RESULTS

Treatment within 6 months after hip fracture improved from 7% in 1995 to 31% in 2002, and then remained stable through 2004. Similar patterns were observed among new users, with treatment increasing from 4% in 1995 to 17% in 2002, with no subsequent increase through 2004. Bisphosphonates led other treatments in the frequency of prescribing, except during 1997-99, when calcitonin was the most common. Among women, hormone therapy prescribing decreased from 22% of those treated in 1995 to 4% in 2004, and raloxifene prescribing remained relatively constant (4%-10%) since its introduction (p for trend = 0.15). Of patients treated before and after hip fracture, 18% changed therapy postfracture. Significantly more patients changed therapy following fracture if a different physician prescribed treatment (26%) compared to those treated by the same physician pre- and postfracture (13%; p < 0.0001).

CONCLUSION

Prescribing practices changed substantially over the 10 years of study. The proportion of hip fracture patients treated with osteoporosis drugs has increased, but remains low, with fewer than one-third receiving pharmacotherapy.

Improving women's health through modernization of our bioinformatics infrastructure

Our nationwide bioinformatics infrastructure used to detect important sex differences associated with medical product use is antiquated. The Food and Drug Administration (FDA) has embarked on an ambitious bioinformatics modernization effort that will improve our ability to assess the safety and effectiveness of new medical products. This, in turn, will improve our ability to detect important sex differences.

Long-term trends of angiotensin-converting enzyme inhibitor and angiotensin-receptor blocker use after heart failure hospitalization in community-dwelling seniors

BACKGROUND

Despite multiple trials demonstrating the benefit of angiotensin-converting enzyme inhibitors (ACEIs) and angiotensin-receptor blockers (ARBs) for heart failure (HF) patients with systolic dysfunction, studies have reported underuse of these drugs. Little is known about recent trends in the use of ACEI/ARB in community-dwelling seniors.

METHODS

Using administrative data from pharmacy assistance programs and Medicare in two states, we identified all patients hospitalized for HF between 1995 and 2004 who survived >or=90 days after discharge. The study outcomes were filled prescriptions for an ACEI or ARB within 90 days after discharge. We assessed age, gender, race, and comorbidities. Multivariate modified Poisson regression was used to analyze temporal trends.

RESULTS

Of 54,453 patients identified, 26,166 (48%) filled prescriptions for ACEIs/ARBs within 90 days after discharge from HF, but utilization of these drugs did not increase during the decade studied. Among those who were on ACEI/ARB before the index hospitalization, 74% filled at least one ACEI/ARB prescription within 90 days after the hospitalization. These results were similar among the subgroup of HF patients with prior MI.

CONCLUSIONS

Use of ACEI/ARB after discharge from HF hospitalization in seniors did not increase over the decade of observation and may still be inadequate.

Ten-year trends of cardiovascular drug use after myocardial infarction among community-dwelling persons > or =65 years of age

Guidelines for post-myocardial infarction (MI) management emphasize treatment with statins, beta blockers (BBs), and angiotensin-converting enzyme inhibitors (ACEIs) or angiotensin II receptor blockers (ARBs). Little is known about the temporal trends and racial differences in such use after discharge. This study assessed temporal trends and racial differences in the use of statins, BBs, and ACEIs or ARBs after MI discharge in community-dwelling seniors. Administrative data from pharmacy assistance programs and Medicare in 2 states (1995 to 2004) were used to identify all patients hospitalized for MI who survived > or =90 days after discharge. Age, gender, race, co-morbidities, and MI-specific procedures during hospitalization were assessed. The study outcomes were filled prescriptions for any statin, BB, or ACEI or ARB <90 days after discharge. Multivariate regression was used for trend and racial difference analyses. Of 19,368 patients identified, 6,577 (34.0%) filled prescriptions for statins, 12,387 (64.0%) for BBs, and 9,934 (51.3%) for ACEIs or ARBs <90 days after MI discharge. The use of these drugs increased from 1995 to 2004, most steeply for statins (11% to 61%), less so for BBs (47% to 80%), and least for ACEIs or ARBs (46% to 58%) (all p for trend <0.001). Black patients were 14% and 5% less likely to receive statins and BBs, respectively (all p <0.05). No evidence of an interaction between race and time trend was found. In conclusion, the use of cardiovascular medications after discharge from MI hospitalization in older patients may still be inadequate but has increased over time. The underuse of statins and BBs was marked in black patients and did not improve over time.

Patterns and predictors of statin use after coronary artery bypass graft surgery

OBJECTIVES

The benefits of statin therapy for patients with coronary artery disease have been well documented, including those occurring after coronary artery bypass graft surgery. The purposes of this study were to assess statin prescription rates in patients who have undergone coronary artery bypass graft surgery and to identify the determinants of postoperative statin administration.

METHODS

A retrospective cohort of 9284 Medicare patients aged 65 years or older who underwent coronary artery bypass graft surgery (1995-2004) was assembled by using linked hospital and pharmacy claims data. Rates of statin use after hospital discharge were calculated, and predictors of postoperative statin use were identified by using generalized estimating equations.

RESULTS

Overall, 35.9% of patients received statins within 90 days of coronary artery bypass graft surgery discharge. Use of statins within 90 days after coronary artery bypass graft surgery steadily improved during the study period, from 13.1% in 1995 to 60.9% in 2004. Patient factors independently associated with an increase in postoperative statin therapy included preoperative statin use (odds ratio, 7.69), later year of operation (odds ratio, 1.22 per additional year), and additional postoperative medications (odds ratio, 1.16 per additional medication). Factors independently associated with a decrease in postoperative statin therapy included peripheral vascular disease (odds ratio, 0.60), diabetes mellitus (odds ratio, 0.67), stroke (odds ratio, 0.77), and older age (odds ratio, 0.96 per additional year). Surgeon and hospital characteristics were not independently associated with postoperative statin use.

CONCLUSIONS

Statins are considerably underused after coronary artery bypass graft surgery, although recent prescription rates are increasing. Patterns of use do not appear to correlate with coronary artery disease risk. These findings highlight the need for targeted quality improvement initiatives to increase the rate of statin administration to this at-risk population.

Uric acid lowering therapy: prescribing patterns in a large cohort of older adults

BACKGROUND

Uric acid lowering therapy (UALT) is considered a chronic treatment for gout. Relatively little is known about adherence to UALT.

METHODS

We assessed adherence with UALT over a 1-year study period among 9823 older adults enrolled in a pharmacy benefit program. Two adherence measures were calculated, the percentage of days covered (PDC) and the time until an extended break (at least 60 days) in treatment. A PDC <80% was considered poor adherence and its predictors were examined in multivariable logistic models.

RESULTS

The mean (SD) PDC was 54% (36%) with 64% of patients considered poorly compliant over the study period. A total of 56% had experienced an extended break in UALT. Predictors of poor adherence included younger age (odds ratio (OR) 1.50, 95% CI 1.33-1.69 for ages 65-74 compared with 85 and above) and African-American race (OR 1.86, 95% CI 1.52-2.27 compared with Caucasian race). Most patients (93%) received their initial UALT prescription from a non-specialist and this also predicted poor adherence (OR 1.15, 95% CI 0.96-1.38 compared with rheumatologists or nephrologists).

CONCLUSION

Adherence with UALT is poor. While uric acid levels were not measured in this study, poor adherence with UALT is likely to reduce attainment of goal uric acid levels.

Anti-tumor necrosis factor alpha therapy and the risk of serious bacterial infections in elderly patients with rheumatoid arthritis

OBJECTIVE

To assess the association between the initiation of anti-tumor necrosis factor alpha (anti-TNFalpha) therapy and the risk of serious bacterial infections in routine care.

METHODS

This was a cohort study of patients with rheumatoid arthritis (RA) in whom specific disease-modifying antirheumatic drugs (DMARDs) were initiated. Patients were Medicare beneficiaries ages 65 years and older (mean age 76.5 years) who were concurrently enrolled in the Pharmaceutical Assistance Contract for the Elderly provided by the state of Pennsylvania. A total of 15,597 RA patients in whom a DMARD was initiated between January 1, 1995 and December 31, 2003 were identified using linked data on all prescription drug dispensings, physician services, and hospitalizations. Initiation of anti-TNFalpha therapy, cytotoxic agents other than methotrexate (MTX), noncytotoxic agents, and glucocorticoids was compared with initiation of MTX. The main outcome measure was serious bacterial infections that required hospitalization.

RESULTS

The incidence of serious bacterial infections was, on average, 2.2 per 100 patient-years in this population (95% confidence interval [95% CI] 2.0-2.4). Glucocorticoid use doubled the rate of serious bacterial infections as compared with MTX use, independent of previous DMARD use (rate ratio [RR] 2.1 [95% CI 1.5-3.1]), with a clear dose-response relationship for dosages >5 mg/day (for < or = 5 mg/day, RR 1.34; for 6-9 mg/day, RR 1.53; for 10-19 mg/day, RR 2.97; and for > or = 20 mg/day, RR 5.48 [P for trend < 0.0001]). Adjusted models showed no increase in the rate of serious infections among initiators of anti-TNFalpha therapy (RR 1.0 [95% CI 0.6-1.7]) or other DMARDs as compared with initiators of MTX.

CONCLUSION

In a large cohort of patients with RA, we found no increase in serious bacterial infections among users of anti-TNFalpha therapy compared with users of MTX. Glucocorticoid use was associated with a dose-dependent increase in such infections.

Agreement of diagnosis and its date for hematologic malignancies and solid tumors between medicare claims and cancer registry data

PURPOSE

Claims data may be a suitable source studying associations between drugs and cancer. However, linkage between cancer registry and claims data including pharmacy-dispensing information is not always available. We examined the accuracy of claims-based definitions of incident cancers and their date of diagnosis.

METHODS

Four claims-based definitions were developed to identify incident leukemia, lymphoma, lung, colorectal, stomach, and breast cancer. We identified a cohort of subjects aged >or=65 (1997-2000) from Pennsylvania Medicare and drug benefit program data linked with the state cancer registry. We calculated sensitivity, specificity, and positive predictive values of the claims-based definitions using registry as the gold standard. We further assessed the agreement between diagnosis dates from two data sources.

RESULTS

All definitions had very high specificity (>or=98%), while sensitivity varied between 40% and 90%. Test characteristics did not vary systematically by age groups. The date of first diagnosis according to Medicare data tended to be later than the date recorded in the registry data except for breast cancer. The differences in dates of first diagnosis were within 14 days for 75% to 88% of the cases. Bias due to outcome misclassification of our claims-based definition of cancer was minimal in our example of a cohort study.

CONCLUSIONS

Claims data can identify incident hematologic malignancies and solid tumors with very high specificity with sufficient agreement in the date of first diagnosis. The impact of bias due to outcome misclassification and thus the usefulness of claims-based cancer definitions as cancer outcome markers in etiologic studies need to be assessed for each study setting.

Statins in elderly patients with acute coronary syndrome: an analysis of dose and class effects in typical practice

OBJECTIVE

To compare the effectiveness of statins of different treatment intensity used to treat elderly patients with acute coronary syndrome (ACS) in typical care settings.

DESIGN

Retrospective cohort study using linked hospital and pharmacy claims data.

SETTING

Statewide pharmacy benefits programmes in Pennsylvania and New Jersey.

PARTICIPANTS

18,311 Medicare patients discharged alive after ACS who received a prescription for a statin within 90 days of hospital discharge.

MAIN OUTCOME MEASURES

Using multivariable and propensity-matched Cox proportional hazards regression models, patients who were prescribed high-intensity and moderate-intensity statins were compared based on the drug-dose combination that they initially received. Individual drug-dose combinations were also compared. Our primary outcome was the composite of all-cause death or recurrent ACS.

RESULTS

Patients who received moderate-intensity statins were as likely to experience a primary outcome as patients treated with high-intensity statins (adjusted HR 1.02, 95% CI 0.96 to 1.08). Propensity matching did not change the results. Individually, all moderate-intensity statins were as effective as high-intensity atorvastatin with the exception of lovastatin (adjusted HR 1.22, 95% CI 1.09 to 1.36). Similarly, all high-intensity statins seem as effective as high-intensity atorvastatin but the CIs surrounding these estimates were wide.

CONCLUSIONS

This analysis of elderly patients with ACS treated in typical care settings does not demonstrate the superiority of high-intensity over moderate-intensity statin treatment or significant differences among individual statins.

Treatment of older adult patients diagnosed with rheumatoid arthritis: Improved but not optimal

OBJECTIVE

The National Committee on Quality Assurance has determined that all patients with rheumatoid arthritis (RA) should be treated with disease-modifying antirheumatic drugs (DMARDs). Our objective was to determine the rate and predictors of DMARD use in a cohort of elderly patients with RA.

METHODS

We analyzed health care utilization data for 5,864 Medicare beneficiaries with RA who also participated in a state-run pharmaceutical benefit program in Pennsylvania. Patients with RA were defined as those with at least 3 diagnoses of RA (International Classification of Diseases, Ninth Revision code 714.xx) at least 1 week apart who were enrolled in these programs for at least 12 months during 1995-2004. Multivariate logistic regression was used to assess predictors of synthetic or biologic DMARD use in the 12 months after cohort entry.

RESULTS

Thirty percent of patients filled a DMARD prescription during 12 months of followup. Frequency of DMARD use increased steadily over time: 24% received DMARDs in 1996 compared with 43% in 2003 (P for trend <0.001). Of patients with at least 1 rheumatologist visit, 41% received a DMARD in 1996 compared with 70% in 2003 (P < 0.001). After the introduction of biologic DMARDs in 1998, 6% of all patients with RA received a biologic, including 12% who saw a rheumatologist. Patients ages 75-84 were 52% less likely to receive DMARDs (95% confidence interval [95% CI] 46-58%) and patients ages >or=85 were 74% less likely (95% CI 69-79%) compared with patients ages 65-74.

CONCLUSION

In this cohort of patients in the community with full prescription drug coverage, most patients diagnosed with RA did not receive a DMARD during the 12 months after cohort entry. Older patients and those not seeing a rheumatologist were less likely to receive a DMARD and may provide a target for quality improvement interventions.

Angiotensin inhibition after myocardial infarction: does drug class matter?

BACKGROUND

Angiotensin converting enzyme-inhibitors (ACEI) and angiotensin-II-receptor blockers (ARB) are equally efficacious in reducing mortality after MI, although the latter are far more costly. Little is known about their relative use after MI in typical care settings, and about their relative effectiveness outside the clinical trial setting.

OBJECTIVES

To assess temporal trends in the relative use of ACEI and ARB after myocardial infarction, and to test for differences in 1-year survival between users of these drug classes.

DESIGN

Retrospective closed cohort study.

PATIENTS

Medicare beneficiaries who survived >90 days after myocardial infarction, had full prescription drug coverage, and who filled a prescription for either ACEI or ARB within 90 days of myocardial infarction.

MEASUREMENTS

Relative use of ACEI versus ARB over time. Adjusted relative 1-year mortality between ACEI and ARB users.

RESULTS

Between 1995 and 2004, 14,190 patients met inclusion criteria. Mean age was 80 years, 75% were female, and 90% were white. Overall, 88% received an ACEI, and 12% an ARB, with the proportion receiving an ARB increasing from 2% (1995) to 25% (2004; P<.001). Multivariate-adjusted 1-year mortality did not differ between ARB and ACEI users (HR: 1.04; 95% confidence interval: 0.88 to 1.22). The findings were similar for new users of ACEI/ARB, and for those with preexisting heart failure.

CONCLUSIONS

ARB users had the same 1-year mortality after myocardial infarction as ACEI users in routine care. Use of more costly ARB has increased dramatically over time, to a quarter of ACEI/ARB users, despite the lack of a therapeutic advantage for most patients.

Assessing health state utilities in elderly patients at cardiovascular risk

BACKGROUND

Health state preferences can be a crucial component of cost-effectiveness analyses, but off-the-shelf health state utilities specifically for older people are not available.

OBJECTIVES

Among participants in PROSPER, a trial of pravastatin in patients>70 years, the authors assessed utilities for the health states that were relevant for the trial's cost-utility analysis.

SUBJECTS AND METHODS

The authors cross-sectionally administered the Health Utilities Index, Mark 3 (HUI) to all PROSPER participants to assess each patient's health state at the time of interview; they then used the scale's multiattribute utility function to estimate the resulting utilities. The population was then stratified into 3 health states, and the mean utility function for each was calculated: recent myocardial infarction (MI, within 3 months), previous MI (>3 months), or no prior MI. Linear and logistic regression were used to control for potential demographic and clinical characteristics.

RESULTS

Of the 5804 patients enrolled in the trial, 4677 were administered the HUI instrument. The likelihood of having a complete HUI response set decreased with higher age (P<0.001) but not with the other variables studied. A complete utility score could be calculated for 3390 participants. Of these, 2755 (81.3%) had no history of MI, 546 (16.1%) had an MI>3 months previously, and 89 (2.6%) had an MI within 3 months. The mean (median) utilities were virtually identical for these states: 0.75 (0.84), 0.74 (0.84), and 0.74 (0.84), respectively. From multivariate analyses, utilities decreased with higher age and the presence of several other comorbidities (diabetes, stroke, peripheral vascular disease); women had lower utilities than men (all P<0.01).

CONCLUSIONS

In this large implementation of the HUI in elderly patients, the instrument did not detect any differences in estimated utilities related to having a MI. Potential causes of nondiscrimination for MI include the possibility that competing comorbidities may reduce the impact of MI on quality of life in this age group, as well as the possibility that a standard instrument derived from and validated in younger populations may not perform as well in elderly people.

Kidney Function and Use of Recommended Medications after Myocardial Infarction in Elderly Patients

Several studies have found reduced use of recommended medications after myocardial infarction (MI) in patients with impaired kidney function. However, the reasons for such undertreatment are not well understood. A total of 1380 Medicare patients who survived at least 90 d after MI and had prescription drug coverage through Pennsylvania's medication assistance program for the elderly were studied. Filled prescriptions were used to assess use of angiotensin-converting enzyme inhibitors (ACEI), angiotensin receptor blockers (ARB), beta blockers, and statins within 90 d of MI. Patients' demographics, comorbidities, and health care utilization before MI also were ascertained. We used logistic regression to test the association between kidney function and postdischarge use of each medication. Overall, 619 (45%) patients filled a prescription for a beta blocker, 675 (49%) received an ACEI or ARB, and 406 (29%) received a statin after discharge but within 90 d after their admission for MI. Reduced kidney function was associated with both lower beta blocker and statin use (P = 0.01 and P = 0.002, respectively), but after multivariate adjustment, these associations disappeared (P = 0.23 and P = 0.62, respectively). Use of ACEI or ARB was nearly half in patients with estimated GFR <30 ml/min compared with patients with better kidney function in univariate and multivariate analyses (P < 0.001). Analyses using serum creatinine measurements rather than estimations of GFR yielded similar results. Differences in other characteristics such as age, rather than kidney function, may be responsible for much or all the reported reduction in use of preventive medications after MI seen in patients with chronic kidney disease.

Drug-induced home cage conspecifics' behavior can potentiate behavioral sensitization in mice

The effect of home cage conspecifics' behavior on locomotor sensitization to amphetamine (AMP) or ethanol (ETOH) were investigated. Female mice were repeatedly treated with saline or AMP (2.0 mg/kg for 13 days--Experiment 1) or saline or ETOH (1.8 g/kg for 21 days--Experiment 2) in home cages where all the animals had the same treatment (homogeneous home cages--HOM-HC) or in home cages where half of the animals were drug-treated and half of them were saline-treated (heterogeneous home cages--HET-HC). Behavioral sensitization was evaluated by the quantification of open-field locomotor activity after AMP or ETOH challenge injection, respectively. In both experiments, behavioral sensitization was potentiated in HOM-HC maintained animals. These results suggest that the behavioral sensitization phenomenon can be modified by home cage conspecifics' behavior.

Poor short-term survival and low use of cardiovascular medications in elderly dialysis patients after acute myocardial infarction

BACKGROUND

Beta-blockers, statins, angiotensin-converting enzyme (ACE) inhibitors, and angiotensin receptor blockers (ARBs) are standard therapies after myocardial infarction (MI) in the general population. Their use and association with mortality in elderly dialysis patients after MI have not been studied sufficiently.

METHODS

Claims records from Medicare and Medicaid patients aged 65 years and older who participated in prescription benefit plans of 2 eastern states were used to identify dialysis patients with MI between 1995 and 2003. Study outcomes were outpatient use of beta-blockers, statins, and ACE inhibitors and/or ARBs within 90 days after MI. We used multivariate logistic regression to assess predictors of such use. Multivariate Cox regression was applied to test for associations between beta-blocker, statin, and ACE-inhibitor and/or ARB use and 1-year mortality.

RESULTS

We identified 902 dialysis patients who were hospitalized with MI. Of these, 39.5% died within 90 days and 63.6% died within 1 year after MI. Of 494 patients who were discharged within 21 days or less and survived longer than 90 days, 31.0% were administered an ACE inhibitor and/or ARB; 19.4%, a statin; and 34.2%, a beta-blocker after discharge. Use of ACE inhibitors and/or ARBs was associated with a 30% reduction in 1-year mortality (hazard ratio [HR], 0.70; 95% confidence interval [CI], 0.50 to 0.98), whereas statin (HR, 0.97; 95% CI, 0.65 to 1.45) and beta-blocker use (HR, 1.05; 95% CI, 0.78 to 1.43) were not.

CONCLUSION

Elderly dialysis patients have excessively high mortality and low use of standard therapies after MI. Only ACE inhibitors and/or ARBs were associated with a reduced risk for death at 1 year in this population. Whether the high mortality rate in this population is attributable to such low use of preventive cardiovascular medications remains uncertain.

Underuse of ACE inhibitors and angiotensin II receptor blockers in elderly patients with diabetes

BACKGROUND

National guidelines recommend angiotensin-converting enzyme (ACE)-inhibitor or angiotensin receptor blocker (ARB) therapy in patients with diabetes who also have hypertension and/or proteinuria to retard the progression of renal damage. However, little is known about the adequacy of adherence to these guidelines in elderly patients with diabetes and predictors of such appropriate ACE-inhibitor or ARB use.

METHODS

Using linked medical claims from Medicare and the Pennsylvania Pharmaceutical Assistance Contract for the Elderly program, we studied a cohort of patients older than 65 years with diabetes. Baseline variables ascertained included age, sex, race, income, and several specific comorbid conditions. The outcome measure was at least 1 filled prescription for any ACE inhibitor or ARB during the quarter after the baseline year. We used multivariate logistic regression to measure predictors of use of the agents studied.

RESULTS

Of 30,750 patients with diabetes studied, 21,138 patients (68.7%) also had hypertension and/or proteinuria. Of these, only 50.7% (95% confidence interval, 50.0 to 51.4) were administered an ACE inhibitor or ARB in the quarter studied. In multivariate analyses, failure to be administered either agent was associated significantly with older age, male sex, chronic lung disease, depression, dementia, and other mental illness. Greater rates of ACE-inhibitor or ARB use were found in patients with coronary artery disease or congestive heart failure.

CONCLUSION

Only half the elderly patients with diabetes studied received recommended treatment with ACE inhibitors or ARBs. This shortfall could provide an opportunity for quality-improvement interventions that could result in important benefits in clinical outcomes for these high-risk patients.

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.

First Report of Meloidogyne partityla on Pecan in Florida

Pecan (Carya illinoensis (Wagenh.) K. Koch) is an important tree in the southern United States for commercial nut production and residential use. Meloidogyne partityla (pecan root-knot nematode) is only known to parasitize trees in the Juglandaceae including pecan, walnut, and hickory. In the United States, it has been reported on pecan in Texas, New Mexico, and Georgia and internationally in South Africa. Portions of a large pecan nursery in Madison County, Florida were infested with an unknown species of root-knot nematode. The pecan trees at this nursery are grafted onto rootstock and grown in the field until the trees are large enough to sell as bare-root transplant stock in several states including and adjoining Florida. Trees infected by the root-knot nematodes were stunted, had extensive galling and rotting of the root system, and pulled from the ground relatively easily compared with noninfected trees. Attempts to rear these nematodes on tomato in the greenhouse were unsuccessful. Young egg-laying females were isolated directly from pecan roots for speciation. Enzymes extracted from females were resolved with polyacrylamide gel electrophoresis [4% stacking (pH 6.8) and 8% separating gel (pH 8.8) with Tris-glycine buffer]. The esterase (Est) and malate dehydrogenase (Mdh) phenotypes of the unknown Meloidogyne sp. were consistent with those reported for M. partityla. In addition, specimens of M. partityla maintained by the USDA Southeastern Fruit and Tree Nut Research Laboratory in Byron, GA were obtained and their Est and Mdh phenotypes compared with the unknown Meloidogyne sp. under identical electrophoretic and enzyme staining protocols. The Est and Mdh phenotypes of the two isolates were identical. Therefore, we conclude that the root-knot nematodes infesting the pecan nursery in Florida are M. partityla. To our knowledge, this is the first report of this nematode in Florida and also the first report of this nematode from infected nursery stock. It is unknown how long the field has been infested but clearly, there is potential for spread of M. partityla to locations around Florida and bordering states. This nematode may be widespread throughout pecan-growing regions of the United States. References: (1) K. P. N. Kleynhans. Phytophylactica 18:103, 1986. (2) A. P. Nyczepir et al. Plant Dis. 86:441, 2002. (3) J. L. Starr et al. J. Nematol. 28:565, 1996. (4) S. H. Thomas et al. Plant Dis. 85:1030, 2001.

Nonsteroidal antiinflammatory drugs and nonunion of humeral shaft fractures

OBJECTIVE

To analyze the relationship between nonunion of humeral shaft fractures and nonsteroidal antiinflammatory drug (NSAID) exposure in older adults.

METHODS

A cohort of 9,995 patients with humeral shaft fractures was identified using diagnosis and procedure codes from a Medicare database of >500,000 patients. Prescription NSAID as well as prescription opioid use was assessed from pharmacy claims data for 3 30-day periods immediately after the initial fracture. Nonunion was defined by the presence of procedure codes for repair of nonunion 90-365 days after the index fracture. We examined the association between NSAIDs and nonunion using multivariate Cox proportional hazards models.

RESULTS

Of the 9,995 humeral shaft fractures, 105 patients developed nonunions (1.1%), and 1,032 (10.3%) were exposed to NSAIDs in the 90 days after fracture. NSAID exposure within the first 90 days was significantly associated with nonunion (relative risk [RR] 3.7, 95% confidence interval [95% CI] 2.4-5.6). When indicators for exposure to NSAIDs during each of the 3 30-day windows were placed into the same multivariate model, only the period 61-90 days post-fracture was significantly associated with nonunion (RR 3.9, 95% CI 2.0-6.2). We observed a similar association between opioids and nonunion, with exposure to opioids between 61 and 90 days associated with nonunion (RR 2.7, 95% CI 1.5-5.2), but exposure to opioids during neither of the 2 earlier 30-day periods significantly associated with nonunion.

CONCLUSION

We found that exposure to nonselective NSAIDs or opioids in the period 61-90 days after a humeral shaft fracture was associated with nonunion. Although these associations may be causal, they are more likely to reflect the use of analgesics by patients with painful nonhealing fractures.

Sudden Uncontrollable Somnolence and Medication Use in Parkinson Disease

BACKGROUND

Episodes of sudden uncontrollable somnolence have been reported in patients with Parkinson disease (PD) receiving dopamine agonists, including pramipexole and ropinirole, but controversy persists concerning their nature, severity, and frequency.

OBJECTIVES

To quantify the risk of sudden uncontrollable somnolence in patients taking specific PD medications and to define its predictors.

METHODS

We contacted 929 patients with PD and administered a 45- to 60-minute interview addressing medication use, adverse events, and the patient's clinical status in the preceding 6 months. Their physicians completed record reviews detailing their clinical histories and drug regimens. The outcome of interest in this case-control study was an episode of somnolence that was uncontrollable, severe, and inappropriate, such as while driving or engaged in social activity. For multiple events, the first was chosen as the index event. For each case, we sampled control time from all respondents who had no event as of the index time for that case. Multiple logistic regression was used to adjust for potential confounders.

RESULTS

Episodes of uncontrollable somnolence were reported by 22% of all respondents. After controlling for age, sex, PD duration and severity, frailty, and other medication use, we found that patients receiving a dopamine agonist (pramipexole, ropinirole, or pergolide) were nearly 3-fold as likely to have episodes of sudden uncontrollable somnolence (odds ratio, 2.8; 95% confidence interval, 1.8-4.2) compared with all other PD medication users. Similar risks were seen for the 3 agents, pramipexole, ropinirole, and pergolide, each compared with levodopa alone (odds ratio, 2.2, 1.8, and 2.1, respectively), with a clear dose-response relationship for each. No increase in risk was seen with any other drugs studied.

CONCLUSIONS

Dopamine agonists widely used for the management of PD significantly increase the risk of sudden uncontrollable somnolence in a dose-related manner. Greater attention to this potentially serious adverse effect will be necessary to improve the safety of use of this important category of PD drugs.