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Pharmacologic management of heart failure among older adults by office-based physicians in the United States.

Heart failure is a major health problem among older adults. (1) Traditional therapeutic approaches involve counteracting compensatory mechanisms of the pathophysiology of heart failure rather than reversing specific defects in dysfunctional myocardium. (2,3) Although information is available regarding recent trends in the pharmacologic management of hypertension (4-7) and myocardial infarction, (8-10) little is known about drug utilization patterns for heart failure in the United States. For several decades, heart failure research has focused on the therapeutic benefits of vasodilators. (11,12) In 1986, Hlatky et al (13) assessed whether changes in the understanding and treatment of heart failure had been accepted into clinical practice. Survey results showed that most physicians considered diuretics to be first-line therapy for heart failure. Furthermore, physicians reported using vasodilatots in addition to digitalis and diuretics as therapeutic options for heart failure; the most commonly used vasodilators, in order of physician preference, were nitrates, captopril, hydralazine, and prazosin. (13)

Clinical trials conducted during the past decade assessed the impact of various drug treatments on the management of heart failure among patients with a left-ventricular ejection fraction [less than or equal to] 45%. (14,15) The clinical trials demonstrated improved survival with therapies that included angiotensin-converting enzyme (ACE) inhibitors, hydralazine, and isosorbide dinitrate. (16,19) Several studies found, however, that other treatment strategies for patients with advanced symptoms provided symptomatic benefit but may have impaired survival. (20-22)

Little is known about the actual pharmacologic management practices for heart failure at the time that these clinical trial results were published. The National Ambulatory Medical Care Survey (NAMCS) is the only national surveillance system that examines the drug-prescribing patterns of office-based physicians. Survey years 1991 and 1992 represent the most recent data available for analysis of these patterns. Thus, the NAMCS affords the opportunity to expand our understanding of physician drug utilization patterns during and immediately following initial publications of clinical trial results. This study also provides insight into the characteristics of physician encounters with older patients who have heart failure.

METHODS

The NAMCS is designed and conducted by the National Center for Health Statistics, Centers for Disease Control and Prevention; data are collected by the US Bureau of the Census. The three-stage probability sampling procedure, sampling variance, and estimation procedures for the NAMCS have been described elsewhere. (23-26) The basic sampling unit is the physician-patient encounter. In brief, names of office-based physicians (defined as nonfederally employed physicians principally engaged in patient care activities in the office) were selected in 1991 (2540 physicians) and 1992 (3000 physicians) from master tiles of the American Medical Association and American Osteopathic Association in 112 primary sampling units (ie, counties, groups of counties, townships, or standard metropolitan statistical areas). Physicians were excluded for retirement, death, or employment in teaching, research, or administration. The total physician sample was divided into 52 random subsamples and randomly assigned to 1 week in the survey year. During the assigned week, the physician selected a systematic random sample of patient visits to assess for the survey.

There were 33,795 patient records completed by 1354 (72%) of 1887 eligible physicians in 1991, and 34,606 records completed by 1558 (73%) of 2142 eligible physicians in 1992. This study is limited to 16,968 office visits of patients aged [greater than or equal to] 65 years. Physician specialities were grouped as cardiology (n=1273 visits), which included cardiovascular disease surgeons; internal medicine (n=2004); general and family practice (n=2522); and all other specialists and surgeons (n=11,169).

After receiving instructions from a field representative, the physician and office staff recorded information on patient characteristics (date of birth, sex, and race); expected sources of payment; up to three reasons, complaints, or symptoms given by the patient for the visit; a subjective assessment of depression, hypertension, hypercholesterolemia, or obesity; a maximum of three diagnoses; the provision of selected diagnostic or screening procedures, selected patient education, counseling or other therapeutic services; and a maximum of five medications.

Physicians were instructed to record specific brand or generic names for all new and continued medications that they prescribed, injected, administered, or provided during the visit. Both brand and generic code numbers were assigned from the National Drug Code Directory, 1982 edition. (27) Drugs were grouped into classes of antihypertensive agents in the manner described by Manolio et al (4): diuretics, ACE inhibitors, beta blockers, and calcium antagonists. A fifth category for other antihypertensives included hydralazine, reserpine, other vasodilators, and central-acting agents. We also defined specific classes of drugs to include other medications commonly used for heart failure, including digitalis compounds, nitrates, and aspirin. The generic drugs included in these classes are described by Konstam et al. (28) For some analyses, diuretics were further classified as thiazide, loop, and potassium-sparing. A maximum of five ingredients were coded for each combination drug. We counted combination drugs once for each drug class (eg, a combination drug containing both captopril and hydrochlorothiazide as ingredients was counted as both an ACE inhibitor and a diuretic).

The International Classification of Diseases, Ninth Revision, Clinical Modification (ICD-9-CM), Third Edition (29) was used to code diagnoses. Heart failure was defined if the record included ICD-9-CM diagnosis codes 428-428.9, 402.01, 402.11, 402.91, 404.01, 404.03, 404.11, 404.13, 404.91, or 404.93. To ascertain whether physicians were prescribing the selected antihypertensive medications to anyone during this period, we included as another comparison group adults with hypertension but no evidence of heart failure. Hypertension was defined if it was reported as part of the assessment, as one of the symptoms of reasons for the office visit, or as an ICD-9-CM diagnosis code 401.0-405.99. Thus, all office visits were classified as either (1) heart failure regardless of hypertension status, (2) hypertension with no diagnosis of heart failure, of (3) no report of either disease.

Frequencies of characteristics and drug classes by heart failure status and physician specialty were weighted to take into account selection probability, nonresponse, and the physician-population weighting ratio adjustment. The National Center for Health Statistics considers an estimate to be unreliable if the relative standard error exceeds 30% (23,24); these unstable national estimates are indicated by asterisks on the tables and figures.

RESULTS

Patients aged 65 years of older made an estimated 323,837,039 office visits in 1991-1992. Among these office visits, 2.6% had diagnosis codes for heart failure. This yields a national estimate of 8,341,886 office visits of older patients with heart failure during the 2-year period. The prevalence of heart failure cases encountered during office visits with older patients varied according to physician specialty: 9.3% among cardiologists, 4.3% among internists, 3.5% among general and family physicians, and 0.6% among other physicians. Among office visit records that had a diagnosis code for heart failure, 38.2% also mentioned hypertension. Hypertension without evidence of heart failure was reported for 31.8% of office visits involving older patients (43.8% of visits to cardiologists, 46.2% to internists, 43.0% to general and family physicians, and 18.7% to other physicians).

Patient characteristics varied according to their heart failure and hypertension status (Table 1). Patients with heart failure comprised a much higher percentage of people who were aged 85 years of older than either patients with hypertension only or patients with no mention of either condition. Patients with heart failure were also somewhat more likely to be assessed as depressed by the physician. Among patients with heart failure and patients with hypertension only, there were greater percentages of women and higher prevalences of obesity and hypercholesterolemia than among patients without evidence of either condition.

Characteristics of the physician-patient encounter also varied with heart failure and hypertension status (Table 2). Patients with heart failure were less likely to have been referred by another physician and were more likely to have seen their physician previously, especially for the same diagnosis. The government was more likely to be expected to be the source of payment for patients with heart failure than for those patients with hypertension only or those with no evidence of either condition. Visits of patients with heart failure and patients with hypertension only were more likely to include patient education or counseling concerning cholesterol reduction, diet, exercise, and weight reduction. Few of these older patients received counseling regarding smoking cessation.

As expected, the rate of prescription of most medication classes commonly used to treat hypertension or heart failure or both was higher for visits of patients with heart failure in contrast to visits that indicated hypertension with no evidence of heart failure and visits with no evidence of either condition on the record form (Figure 1). Among visits of patients with a diagnosis of heart failure, diuretics were mentioned in 69.4% of visits, digitalis compounds in 45.8%, ACE inhibitors in 29.6%, nitrates in 19.3%, calcium antagonists in 16.1%, beta blockers in 6.8%, and other antihypertensive medications in 2.3%. Aspirin was indicated on the patient record for 5.5% of visits by patients with heart failure; there was evidence that aspirin was prescribed for arthritis pain relief in only two cases. Among visits of patients with a diagnosis of heart failure, fewer than 10% included new prescriptions. There was no mention of any antihypertensive medication (diuretics, ACE inhibitors, beta blockers, calcium antagonists, and other antihypertensive drugs) for 20.4% of the patients with heart failure, 45.4% of the patients with hypertension and no diagnosis of heart failure, and 86.7% of the patients who had neither condition.

[FIGURE 1 OMITTED]

Drug utilization for patients with heart failure varied by clinical specialty (Figure 2). Because of the small numbers of patients with heart failure in the survey sample, many national estimates that may be unstable are indicated on the figure. Cardiologists reported a higher prevalence of use of digitalis compounds, ACE inhibitors, and loop diuretics in patients with heart failure than did internists and general or family physicians. While there was an overall prevalence of 30% for use of ACE inhibitors among all physician visits that involved older adults with heart failure, this drug was mentioned during at least 55% of the visits to cardiologists by patients with heart failure.

[FIGURE 2 OMITTED]

DISCUSSION

In 1994, the Agency for Health Care Policy and Research (AHCPR) sponsored the development of clinical practice guidelines for the evaluation and care of patients with heart failure with left-ventricular systolic dysfunction (Table 3). (28,30) The AHCPR guidelines recommended that ACE inhibitors be given to all patients with heart failure with left-ventricular systolic dysfunction unless specific contraindications existed. (28,30) Patients with heart failure with signs of significant volume overload should be started with a diuretic: thiazide diuretics for mild overload and loop diuretics for severe overload. The continuum of recommended therapy ranges from the use of an ACE inhibitor alone for mild manifestations, to the use of an ACE inhibitor, digoxin, a combination of diuretics, and hydralazine hydrochloride or isosorbide dinitrate for patients with heart failure with more severe manifestions. (30) Long-acting nitrates and aspirin are among the recommended treatments for patients who have persistent heart failure and angina but who are not revascularization candidates. Finally, the guidelines cautioned that beta blockers and first-generation calcium antagonists may have negative inotropic effects. (28,30) Similar heart failure guidelines were released in 1995 by a joint task force of the American College of Cardiology and the American Heart Association (ACC/AHA). (31) The NAMCS data for 1991-1992 show that US physicians were already using many of these drugs before publication of these guidelines.

To our knowledge, there were no national clinical practice guidelines for the treatment of heart failure before 1994. Table 4 presents an outline of the drug classes that were recommended in 1987 for the pharmacologic management of congestive heart failure in clinical practice. (32) Depending on the severity in any individual patient, the treatment of the heart failure state was often divided into three categories: (1) enhancement of myocardial contractility with digitalis compounds; (2) control of excessive salt and water retention with diuretics; and (3) reduction of cardiac workload, including afterload with vasodilators. (32) Although vasodilators such as hydralazine, minoxidil, captopril, enalapril, alpha blockers, and nitrates were demonstrated to be useful by 1987, only captopril had been approved for treatment of heart failure in the United States. (32)

Three important differences distinguish current guidelines from earlier conventional practice. First, "congestive" has been dropped from the diagnostic term in recognition that asymptomatic patients with left-ventricular dysfunction will also benefit from therapeutic management. (15) Second, diagnosis and treatment of heart failure is based on measurements of the ejection fraction rather than traditional signs and symptoms. (15,28,30,31) AHCPR heart failure guidelines address treatment only in patients with left-ventricular systolic dysfunction (ie, an ejection fraction [less than or equal to] 40%). (28,30) ACC/AHA guidelines, (31) however, also describe important differences in the drug therapy for patients with left-ventricular diastolic dysfunction (ie, a normal ejection fraction but clinical evidence of pulmonary venous hypertension and congestion). Finally, the new guidelines are distinguished by the emergence of ACE inhibitors as the preferred initial therapy for the pharmacologic management of heart failure in clinical practice. (11)

The current results demonstrate that US physicians in 1991-1992 regarded diuretics as the major therapy for heart failure. During office visits with patients with heart failure, the most frequently prescribed heart failure medications were diuretics (69%), digitalis compounds (46%), and ACE inhibitors (30%). These results ate similar to findings of Hlatky et al, (13) who reported in 1986 that physicians preferred diuretics (83%), digitalis (37%), and any vasodilating agent (9%) as part of the initial therapy for their patients with heart failure. The much greater prevalence of ACE inhibitors in 1991-1992 than in the study by Hlatky et al probably reflects not only the greater availability of this class of drugs during the last decade but also overall changes in the use of specific anti-hypertensive medications.

The 1988 Joint National Committee on Detection, Evaluation, and Treatment of High Blood Pressure (JNC IV) (33) recommended using either a diuretic, beta blocker, calcium antagonist, or ACE inhibitor as the first step of pharmacologic therapy for hypertension. Trends in hypertension management demonstrate that use of ACE inhibitors and calcium antagonists increased dramatically during the last decade with a concomitant decrease in the use of less expensive diuretics, beta blockers, and vasodilators. (4,5) Psaty et al (5) speculated that these trends reflected the influence of the major hypertension clinical trial results on clinical practice; however, during that time only diuretics and beta blockers had been shown to reduce cardiovascular disease morbidity and mortality in hypertension clinical trials. (34) Indeed, recent JNC V recommendations suggest thiazide diuretics and beta blockers as the two classes of drugs preferred for the initial drug therapy for hypertension. (35)

While patients with heart failure in the NAMCS shared many similarities with older patients who had hypertension only, there were several differences between the two groups. More than one fourth of patients with heart failure, compared with 8% of patients with hypertension, were aged 85 years or older. While this proportion of very elderly patients with heart failure may seem high in contrast to clinical trial study populations, this national estimate is similar to the proportions of adults aged 85 years or older among Medicare patients with an initial hospitalization for heart failure in 1993 (22% of 67,700 black patients with heart failure and 27% of 735,806 white patients with heart failure). (36) Unlike results often reported for study populations in the literature, these national estimates demonstrate the heterogeneity of characteristics among patients with heart failure seen in actual clinical practice in contrast to the homogeneous characteristics of patients selected for heart failure clinical trials. Possibly reflecting this greater proportion of much older ages in the heart failure group and the likelihood that fewer private resources remained for this older group, the government was expected to be the source of payment for almost 90% of office visits of patients with heart failure in contrast to 84% of hypertensive patients with no mention of heart failure.

Because the physician had seen the patient before for the same diagnosis in almost 86% of encounters with patients with heart failure, these results also demonstrate that the office visits of patients with heart failure are substantially more likely to represent a continuity of care than the office visits of older patients who have neither hypertension nor heart failure. Furthermore, there were new antihypertension prescriptions in fewer than 10% of the visits of patients with heart failure.

ACE inhibitors were also more likely to be prescribed for patients with heart failure than for patients with hypertension only. Given the potential benefits of ACE inhibitors in the pharmacologic management of heart failure, however, the prevalence of ACE inhibitor use in 1991-1992 was low. Nevertheless, prevalences of ACE inhibitor use among 30% of patients with heart failure and among 15% of patients with hypertension but with no evidence of heart failure in the 1991-1992 NAMCS are consistent with trends for management of myocardial infarction and hypertension. Regional prevalences of ACE inhibitor use ranged between 18% and 23% in 1990-1993 among patients hospitalized for acute myocardial infarction in 6306 US hospitals. (10) Trends based on data from the National Disease and Therapeutic Index show that ACE inhibitors accounted for 0.8% of all hypertensive drug mentions in 1982 and increased to 24% by 1993. (4) In a cohort of adults aged [greater than or equal to] 65 years who were selected from four US communities, about 14% of those who had a reported history of hypertension were taking ACE inhibitors in 1990 (6); the prevalence of ACE inhibitor use among persons beginning to take antihypertensive medications ranged between 23% and 26% during 1989-1992 in this cohort. (5) Use of ACE inhibitors was high among NAMCS cardiologists treating patients with heart failure (55%); this is similar to ACE inhibitor use by 58% of patients with heart failure in a 1993 cardiology clinic-based study. (37)

The NAMCS results show that an estimated 4 million office visits of patients with heart failure occurred each year. Cardiologists, internists, general practitioners, and family physicians were more likely than other physicians to encounter older adults with heart failure during office visits. It has been estimated that primary care physicians account for 78% of the clinic visits of patients with heart failure, while cardiologists represent only 18% of these visits. (38) The use of ACE inhibitors, digitalis compounds, and loop diuretics was lower among internists and general and family physicians than among cardiologists.

This study is limited by the sample size of office visits for heart failure in the NAMCS, which may be too small to provide stable estimates of the utilization of some drug classes by clinical specialty. A second limitation includes the lack of information regarding duration and severity of heart failure cases. Cardiologists may be more likely than other physicians to encounter more severe stages of heart failure that require more aggressive drug therapy. They may also be more familiar with recent literature on heart failure, clinical trial results, and clinical practice guidelines. Furthermore, noncardiologists may be more reluctant to use ACE inhibitors because two widely publicized studies in 1985 and 1986 reported renal dysfunction and severe hypotension with the use of large doses of ACE inhibitors among severely ill patients. (39-41) Although general practitioners and internists were undersampled in 1992, (25) specialty-specific prevalences did not differ between 1991 and 1992. Thus, differences among specialties cannot be explained by this undersampling.

It is possible that lower prescription prevalence estimates observed during the surveyed encounter among internists and general and family physicians reflect prescriptions at previous encounters if primary care physicians see patients with heart failure more frequently than do cardiologists. Furthermore, this limitation of the NAMCS study design may result in an overall underestimate of the total prescription prevalences of antihypertension medications. Nevertheless, these findings represent the only nationally representative data to examine differences between clinical specialties in the pharmacologic management of heart failure. Furthermore, this difference in prescribing patterns between specialties is supported by consumer research data. (38)

Other limitations of the NAMCS data should be considered in the interpretation of these results. Over 2.6% of all office visits of older patients and 3.5% of office visit encounters between older patients and a general of family physician involved heart failure. Unfortunately, because of the complex sampling design of the NAMCS, we cannot infer that these findings translate into a prevalence of 2.6% of all older adults being diagnosed with heart failure. This estimate is remarkably similar, however, to rates for an initial hospital admission with heart failure as a diagnosis among the 1993 Medicare population, aged [greater than or equal to] 65 years. (36) If physicians had poor reliability for recording chronic and recurring conditions seen on repeated visits, (42) cases of heart failure and hypertension may be underrepresented in this survey because the NAMCS relies on chart diagnoses rather than standardized measurements of left ventricular ejection fractions and blood pressure levels. Finally, the NAMCS provides no information regarding dosage, compliance, or history of adverse effects that might influence the physician's choice of drug class. (43)

Despite the potential limitations of this study, the results have important implications. First, it is apparent that the overall use of ACE inhibitors among patients with heart failure was low in 1991-1992, suggesting that the results of heart failure clinical trials may not yet have made an impact on physician practices. Nevertheless, these data provide important baseline levels for monitoring changes in physician response to the 1994 clinical guidelines, to the resulting professional education efforts, and to more recent clinical trial results. If these pre-guideline estimates ate not taken into account, an inflated estimate of the "effect size" is likely to occur for assessing the impact of these influences on changes in physician practices. (44) Second, these results suggest that physicians in different clinical specialties may use different classes of medications to treat heart failure. This suggests a need for further monitoring of physician practices. Educational initiatives are needed to ensure that clinical practice guidelines for the evaluation and care of patients with heart failure are followed appropriately by all physicians who encounter these patients and to ensure consistency in the pharmacologic management of this condition.
TABLE 1
Patient Characteristics Among Adults Aged [greater or equal to]
65 Years, Examined in Office-Based Visits, by Heart Failure and
Hypertension Status: National Ambulatory Medical Care Survey,
1991-1992

                                      Hypertension     No Report of
                                      with No          Hypertension
                          Heart       Diagnosis of     or Heart
Patient                 Failure, %    Heart Failure,   Failure, %
Characteristic           (n=352)       % (n=4590)      (n=12,026)

Aged [greater than or     26.8            8.8             8.5
   equal to] 85 years
Women                     60.6           65.6            57.1
White                     91.8           85.7            93.5
Black                      6.1 *         11.3             4.5
Other                      2.1 *          3.0             2.0
Hispanic origin            4.7 *          4.5             4.4
Depressed ([dagger])       8.6            7.8             6.2
Obese ([dagger])           9.8           16.8             5.8
Hypercholesterolemic      12.5           22.1             5.8
   ([dagger])

* Unstable estimates. Relative standard error is greater than 30%.

([dagger]) By physician assessment of the patient.

NOTE: The national estimate of numbers of office visits for heart
failure, 8,341,886; for hypertension with no diagnosis of heart
failure, 102,976,634; visits with no report of hypertension or
heart failure, 212,518,519.
TABLE 2
Characteristics of the Physician-Patient Encounter Among Adults
Aged [greater than or equal to] 65 Years, Examined in Office-Based
Visits, by Heart Failure and Hypertension Status: National
Ambulatory Medical Care Survey, 1991-1992

                                           Hyper-
                                           tension       No Report
                                           with No       of Hyper-
                                 Heart     Diagnosis      tension
                                Failure,    of Heart      or Heart
Characteristic                      %       Failure, %    Failure, %

Visit not a referral              98.5         96.1         92.4
Ever saw patient before           94.8         92.6         87.6
Ever saw patient before           85.5         77.4         72.3
   for same diagnosis
Government (including Medicare    88.7         84.0         80.7
   and Medicaid) expected to
   be source of payment
Patient counseling
   Diet                            28.5         23.3          7.7
   Exercise                        11.2         12.2          5.5
   Cholesterol reduction            6.6 *       10.3          2.3
   Weight reduction                 6.5 *        8.6          1.6
   Smoking cessation                1.1 *        2.0          1.4

* Unstable estimate. Relative standard error is greater than 30%.
TABLE 3
Agency for Health Care Policy and Research (1994) Clinical Practice
Guidelines for the Pharmacologic Management of Patients with Heart
Failure with Left-Ventricular Systolic Dysfunction

Symptoms          Initial Strategy           If Symptoms Not Resolved

Mild DOE, no      Initiate and titrate ACE   Add diuretic (if not
clinical volume   inhibitor; monitor it      resolved, follow next
overload          symptoms resolve           step)

Moderate DOE or   Inititate diuretic;        Add digoxin (if not
mild DOE with     initiate and titrate       resolved, follow next
clinical volume   ACE inhibitor; monitor     step)
overload

Severe DOE        Initiate diuretic,         Aggressive diuretic
                  ACE inhibitor,             therapy for persistent
                  and digoxin; monitor       volume overload

                                             Hydralazine and/or
                                             nitrates for persistent
                                             dyspnea

                                             Direct vasodilator or
                                             alpha blocker for
                                             persistent hypertension

                                             Nitrates and aspirin
                                             for concomitant angina

DOE denotes dyspnea on exertion.
TABLE 4
Drug Classes Recommended for the Pharmacologic Management of
Congestive Heart Failure Prior to Publication in 1994 of the
Agency for Health Care Policy and Research Clinical Practice
Guidelines

Treatment Strategies   Drug Classes Recommended *

Improve myocardial     Digitalis compounds
contractility

Control excessive      Thiazide diuretics
fluid retention        Metolazone (thiazide-related)
                       Loop diuretics
                       Potassium-sparing diuretics

Reduce afterload       Hydralazine ([dagger])
                       Minoxidil ([dagger])
                       ACE inhibitors (captopril,
                       enalapril) ([dagger])
                       Alpha blockers (prazosin,
                       phentolamine) ([dagger])
                       Nitrates (nitroglycerin, isosorbide
                       dinitrate) ([dagger])

* From Braunwald. (32)

([dagger]) Demonstrated to be useful, but only captopril had
been approved for heart failure treatment in the US prior to
publication if 1987. (32)


REFERENCES

(1.) May DS, Kelly JJ, Mendlein JM, Garbe PL. Surveillance of major causes of hospitalization among the elderly, 1988. In: CDC surveillance summaries, April 1991. MMWR 1991; 40(no. SS-1):7-21.

(2.) Parmley WW. Pathophysiology and current therapy of congestive heart failure. J Am Coll Cardiol 1989; 13:771-85.

(3.) Francis GS, Cohn JN. Heart failure: mechanisms of cardiac and vascular dysfunction and the rationale for pharmacologic intervention. FASEB J 1990; 4:3068-75.

(4.) Manolio TA, Cutler JA, Furberg CD, Psaty BM, Whelton PK, Applegate WB. Trends in pharmacologic management of hypertension in the United States. Arch Intern Med 1995; 155:829-37.

(5.) Psaty BM, Koepsell TD, Yanez ND, et al. Temporal patterns of antihypertensive medication use among older adults, 1989 through 1992. An effect of the major clinical trials on clinical practice? JAMA 1995; 273:1436-8.

(6.) Psaty BM, Lee M, Savage PJ, Rutan GH, German PS. Lyles M (for the Cardiovascular Health Study Collaborative Research Group). Assessing the use of medications in the elderly: methods and initial experience in the cardiovascular health study. J Clin Epidemiol 1992; 45:683-92.

(7.) Glynn RJ, Brock DB, Harris T, et al. Use of antihypertensive drugs and trends in blood pressure in the elderly. Arch Intern Med 1995; 155:1855-60.

(8.) Hlatky MA, Cotugno HE, Mark DB, O'Connor C, Califf RM, Pryor DB. Trends in physician management of uncomplicated acute myocardial infarction, 1970 to 1987. Am J Cardiol 1988; 61: 515-18.

(9.) Pashos CL, Normand ST, Garfinkle JB, Newhouse JP, Epstein AM, McNeil BJ. Trends in the use of drug therapies in patients with acute myocardial infarction: 1988 to 1992. J Am Coll Cardiol 1994; 23:1023-30.

(10.) Pilote L, Califf RM, Sapp S, et al. Regional variation across the United States in the management of acute myocardial infarction. N Engl J Med 1995; 333:565-72.

(11.) Chatterjee K. Heart failure therapy in evolution [editorial]. Circulation 1996; 94:2689-93.

(12.) Groden DL. Vasodilator therapy for congestive heart failure: lessons from mortality trials. Arch Intern Med 1993; 153:445-54.

(13.) Hlatky MA, Fleg JL, Hinton PC, et al. Physician practice in the management of congestive heart failure. J Am Coll Cardiol 1986; 8:966-70.

(14.) Armstrong PW, Moe GW. Medical advances in the treatment of congestive heart failure. Circulation 1994; 88:2941-52.

(15.) Gaasch WH. Diagnosis and treatment of heart, failure based on left ventricular systolic or diastolic dysfunction. JAMA 1994; 271:1276-80.

(16.) Cohn JN, Archibald DG, Ziesche S, et al. Effect of vasodilator therapy on mortality in chronic congestive heart failure. N Engl J Med 1986; 314:1547-52.

(17.) The CONSENSUS Trial Study Group. Effects of enalapril on mortality in severe congestive heart failure: results of the Cooperative North Scandinavian Enalapril Survival Study (CONSENSUS). N Engl J Med 1987; 316:1429-35.

(18.) The SOLVD Investigators. Effect of enalapril on survival in patients with reduced left ventricular ejection fractions and congestive heart failure. N Engl J Med 1991; 325:293-302.

(19.) Cohn JN, Johnson G, Ziesche S, et al. A comparison of enalapril with hydralazine-isosorbide dinitrate in the treatment of chronic congestive heart failure. N Engl J Med 1991; 325:303-10.

(20.) Uretsky BF, Jessup M, Konstam MA, et al. Multicenter trial of oral enoximone in patients with moderate to moderately severe congestive heart failure: lack of benefit compared to placebo. Circulation 1990; 82:774-80.

(21.) Xamoterol in Severe Heart Failure Study Group. Xamoterol in severe heart failure. Lancet 1990; 336:116.

(22.) Packer M, Carver JR, Rodeheffer RJ, et al. Effect of oral milrinone on mortality in severe chronic heart failure. N Engl J Med 1991; 325:1468-75.

(23.) Bryant E, Shimizu I. Sample design, sampling variance, and estimation procedures for the National Ambulatory Medical Care Survey. National Center for Health Statistics, Vital and Health Statistics 1988, series 2, No. 108. DHHS publication No. (PHS) 88-1382.

(24.) Schappert SM. National Ambulatory Medical Care Survey, 1991 summary. Vital and Health Statistics 1994, series 13, No. 116. DHHS publication No. (PHS) 94-1777.

(25.) Schappert SM. National Ambulatory Medical Care Survey, 1992 summary. Advance data from Vital and Health Statistics, No. 253. Hyattsville, Md: National Center for Health Statistics, 1994. DHHS publication No. (PHS) 95-1885.

(26.) McCaig LF, Hughes JM. Trends in antimicrobial drug prescribing among office-based physicians in the United States. JAMA 1995; 273:214-19.

(27.) Food and Drug Administration. National drug code directory, 1982 edition. Washington, DC: Public Health Service, 1982.

(28.) Konstam MA, Dracup K, Baker DW, et al. Heart failure: evaluation and care of patients with left-ventricular systolic dysfunction. Clinical practice guideline No. 11. Rockville, Md: Agency for Health Care Policy and Research, Public Health Service, US Department of Health and Human Services, June 1994. AHCPR publication No. 94-0612.

(29.) Public Health Service and Health Care Financing Administration. International classification of diseases, ninth revision, clinical modification. Washington, DC: Public Health Service, 1980.

(30.) Baker DW, Konstam MA, Bottorff M, Pitt B. Management of heart failure. I. Pharmacologic treatment. JAMA 1994; 272: 1361-6.

(31.) ACC/AHA task force report: guidelines for the evaluation mad management of heart failure: report of the American College of Cardiology/American Heart Association Task Force on Practice Guidelines (committee on evaluation mad management of heart failure). J Am Coll Cardiol 1995; 26:1376-98.

(32.) Braunwald E. Heart failure. In: Braunwald E, Isselbacher KJ, Petersdorf RG, Wilson JD, Martin JB, Fauci AS. Harrison's principles of internal medicine, 11th ed. New York, NY: McGraw-Hill, 1987:905-16.

(33.) 1988 Joint National Committee. The 1988 report of the Joint National Committee on Detection, Evaluation, and Treatment of High Blood Pressure. Arch Intern Med 1988; 148:1023-38.

(34.) Alderman MH. Which antihypertensive drugs first--and why! JAMA 1992; 267:2786-7.

(35.) Joint National Committee on Detection, Evaluation, and Treatment of High Blood Pressure. The fifth report of the Joint National Committee on Detection, Evaluation, and Treatment of High Blood Pressure (JNC V). Arch Intern Med 1993; 153:154-83.

(36.) Croft JB, Giles WH, Pollard RA, Casper ML, Anda RF, Livengood JR. National trends in the initial hospitalization for heart failure. J Am Geriatr Soc 1997. In press.

(37.) Oka RK, Stotts NA, Dae MW, Hasken WL, Gortner SR. Dally physical activity levels in congestive heart failure. Am J Cardiol 1993; 71:921-5.

(38.) Rajfer SI. Perspective of the pharmaceutical industry on the development of new drugs for heart failure. J Am Coll Cardiol 1993; 22(suppl A): 198A-200A.

(39.) Failure to treat heart failure [editorial]. Lancet 1992; 339:278-9.

(40.) Packer M, Lee WH, Yoshak M, Medina N. Comparison of captopril and enalapril in patients with severe chronic heart failure. N Engl J Med 1986; 315:847-53.

(41.) Cleland JGF, Dargie HJ, McAlpine H, et al. Severe hypotension after first, dose enalapril in heart failure. Br Med J 1985; 291:1309-12.

(42.) Broadhead WE, Larson DB, Yarnall KSH, Blazer DG, Tse C-KJ. Tricyelic antidepressant prescribing for nonpsychiatric disorders: an analysis based on data from the 1985 National Ambulatory Medical Care Survey. J Fam Pract 1991; 33:24-32.

(43.) Hohmann AA, Larson DB, Thompson JW, Beardsley RS. Psychotropic medication prescription in US ambulatory care. DICP Ann Pharmacother 1991; 25:85-9.

(44.) Pippalla RS, Riley DA, Chinburapa V. Influencing the prescribing behavior of physicians: a meta-evaluation. J Clin Pharm Ther 1995; 20:189-98.

Janet B. Croft, PhD; Wayne H. Giles, MD, MS; Russell H. Roegner, PhD; F. Anda, MD, MS; Michele L. Casper, PhD; and John R. Livengood, MD

Submitted, revised, January 17, 1997.

From the National Center for Chronic Disease Prevention and Health Promotion, Centers for Disease Control and Prevention, Atlanta, Georgia. Requests for reprints should be addressed to Janet B. Croft, PhD, Cardiovascular Health Studies Branch, Mailstop K-47, Centers for Disease Control and Prevention, 4770 Buford Hwy NE, Atlanta, GA 30341-3724.
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Author:Croft, Janet B.; Giles, Wayne H.; Roegner, Russell H.; Anda, Robert F.; Casper, Michelle L.; Livengo
Publication:Journal of Family Practice
Date:Apr 1, 1997
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