A Systematic Approach to Improve Lipids in Coronary Artery Disease Patients Participating in a Cardiac Rehabilitation Program

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1 c e... A Systematic Approach to Improve Lipids in Coronary Artery Disease Patients Participating in a Cardiac Rehabilitation Program Sophia Boudoulas Meis, DO; Richard Snow, DO; Michelle LaLonde, MS; James Falko, MD; Teresa Caulin-Glaser, MD, FACC... h PURPOSE: To determine the effectiveness of an intervention, directed toward the primary care physician (PCP), to improve the number of patients treated to low-density lipoprotein cholesterol (LDL-C) goal in a cardiac rehabilitation (CR) population. h METHODS: A pre-post intervention cohort comparison using data collected from participants in a CR program with LDL-C Q100 mg/dl at entry. The control cohort participated in CR between 1/00 and 10/02, 41.5% (n = 178) had an entry LDL-C Q100 mg/dl. The intervention cohort participated in CR between 10/03 and 1/05, 26.4% (n = 67) had an entry LDL-C Q100 mg/dl. The intervention group had identical treatment as the control group as well as the following: each participant with an LDL-C Q100 mg/dl in the intervention cohort had an entry letter sent to his or her cardiologist and PCP from the programs Cardiology Medical Director, detailing the lipid goals and therapeutic options. In addition, monthly faxes on progress toward lipid goals were sent to the PCP. h RESULTS: The control cohort was less likely to achieve LDL-C goal compared with the intervention cohort (43% vs 67%, respectively; P =.001). A patient was also less likely to have a lipid medication change during CR in the control group compared with the intervention group (29% vs 42%, respectively; P =.05). h CONCLUSION: Use of systematic reminders directed at the PCP during CR can substantially increase the percentage of patients achieving nationally recognized LDL-C goals.. K E Y W O R D S cardiac rehabilitation LDL-cholesterol primary care physician From the McConnell Heart Health Center and Riverside Methodist Hospital, OhioHealth, Columbus. Address correspondence to: Teresa Caulin-Glaser, MD, FACC, 3773 Olentangy River Road, Columbus, Ohio ( tcauling@ ohiohealth.com). INTRODUCTION Reduction of cholesterol to The National Cholesterol Education Program (NCEP) goals has been demonstrated to prevent cardiovascular events in patients with existing coronary artery disease (CAD). 1 A meta-analysis of 38 primary and secondary prevention trials found that for every 10% reduction in serum cholesterol, coronary heart disease mortality was reduced by 15% and total mortality risk by 11%. 2 As shown in the Cholesterol and Recurrent Events Trial, cholesterol lowering also reduces coronary events and mortality in those without significantly elevated cholesterol levels, the mean total cholesterol (TC) was 209 mg/dl and mean low density lipoprotein cholesterol (LDL-C) was 139 mg/dl. 3 Unfortunately, many individuals with CAD do not presently reach the LDL-C goal, which is recommended by the NCEP, the American College of Cardiology, the American Heart Association, and the American Diabetes Association. 4Y8 Lipid-altering agents (LAAs), in conjunction with diet and exercise, have been established as key elements in improving lipid profiles in patients who have CAD. 1 Numerous studies have shown that regular exercise Systematic Approach to Improve Lipids / 355

2 results in a significant increase in high-density lipoprotein cholesterol (HDL-C) and an improvement in TC, triglycerides, and LDL-C in individuals with CAD. 9Y12 Overall, therapeutic lifestyle modifications are associated with a 3% to 4% reduction in the risk of coronary heart disease and a 1% decrease in total serum cholesterol. 13 Despite data demonstrating that treatment to NCEP goals reduces subsequent cardiac events, there is growing evidence that one of the barriers to achieving optimum cholesterol levels resides at the physician level. A recent study examining the response to elevated cholesterol in patients with diabetes at 44 separate clinical practices, including primary care delivery sites and specialty practices (diabetes/endocrinology), in the United States from 2000 to 2002 revealed that 55.9% of patients with LDL-C 9100 mg/dl were not on LAA, and of those not receiving treatment, only 5.6% were started on an LAA during the clinic visit. 14 Primary care physicians (PCPs) are instrumental in monitoring and initiating appropriate therapy to achieve LDL-C goal in at risk CAD and CAD-equivalent patients. Health services research studies have been developed to better understand barriers to adequate care. The Cardiac Hospital Atherosclerosis Management Program (CHAMP), performed at a university-affiliated hospital setting, found that LDL-C levels improved after an intervention to initiate statin therapy before hospital discharge on post myocardial infarction (MI) patients with LDL-C Q100 mg/dl. 15 Their goal was to improve secondary prevention in these patients by initiating certain cardiac protective medications in patients known to have had an MI before hospital discharge. Primary care physicians were recommended to follow their patients post hospital discharge to ensure that an LDL-C e100 mg/dl was obtained. The results of this intervention demonstrated a significant increase in the number of patients placed on a statin (pre-champ 6% vs post- CHAMP 86%, P e.01) and achieving an LDL-C e100 mg/dl (pre-champ 6% vs post-champ 58%). Long-term follow-up of the intervention group at 1 year showed a significant decrease in the number of recurrent MIs (pre-champ 7.8% vs post-champ 3.1%, P e.05) as well as cardiac mortality (pre-champ 5.1% vs post-champ 2%, P e.05). In another study, investigators in Canada implemented a nurse-managed surveillance program, under physician supervision, in post MI patients after hospital discharge to improve lipid profiles. 16 These investigators were able to achieve appropriate LDL-C levels (G3.2 mmol/l) in 97% of patients 5 months post MI by sequential measurements of LDL-C levels and institution of treatment for elevated LDL-C through communication/education with the patients and their PCP. Although there have been several studies investigating the effect of systematic delivery system change, primarily with pharmacologic therapy, in improving the number of CAD patients achieving cholesterol goals, few have investigated the specific method of using an organized comprehensive cardiac rehabilitation (CR) program as the method of systematic intervention. The goal of our study was to determine the effectiveness of an intervention, directed toward the PCP, to improve the number of patients treated to LDL-C goal in a CR population. Cardiac rehabilitation programs provide an opportunity for modifications of medical therapies after a patient has been discharged from a cardiac-related hospitalization. We hypothesize that the number of patients at LDL-C goal would be higher after implementation of an intervention designed to increase PCP awareness of opportunity gaps in the treatment to NCEP goals. METHODS Study Design The study, approved by the institutional review board, was a pre-post intervention cohort comparison using data collected from patients in a large urban comprehensive CR program with LDL-C Q100 mg/dl at entry. The 2 cohorts consisted of a control group and an intervention group. The control and intervention cohorts participated in Q7 weeks of standard outpatient CR, including exercise training, education, and behavior modification therapy. Education and behavior modification therapy included training, education, and instruction on exercise; management of diet, cholesterol, blood pressure, stress, and glucose; smoking cessation; and weight loss strategies. Nutrition recommendations were based on the NCEP ATP III Therapeutic Lifestyle Changes Diet, 17 with the additional recommendation to include 2 g of plant sterols daily. The education and behavior modification components were implemented by cardiovascular nurses, registered dieticians, exercise physiologists, and a clinical social worker. The intervention group had identical treatment as the control group as well as the following: each participant with an LDL-C Q100 mg/dl in the intervention cohort had an entry letter sent to his or her cardiologist and PCP from the programs Cardiology Medical Director, detailing the lipid goals and therapeutic options. In addition, monthly faxes on progress toward lipid goals were sent to the PCP (Figure 1). Study Population A total of 429 participants in the control cohort participated in CR between 1/00 and 10/02, 41.5% (n = 178) had an entry LDL-C Q100 mg/dl. The intervention cohort included 254 participants who participated in 356 / Journal of Cardiopulmonary Rehabilitation 2006;26:355/360

3 Figure 1. Outline of intervention to improve LDL-C levels. CR between 10/03 and 1/05, 26.4% (n = 67) and had an entry LDL-C Q100 mg/dl. Data Collection All laboratory data were measured in the hospital s central laboratory in accordance with appropriate accredited standards. Demographic, comorbidity, and laboratory information were routinely collected at patient enrollment and at matriculation from the program. with the diagnosis of CAD or cardiac revascularizations were analyzed. Only those participants with LDL-C Q100 mg/dl at the entry of CR were studied. Descriptive statistics were developed and comparisons were made within and between groups using chisquare for dichotomous variables (percentage of patients achieving lipid goals) and t test for continuous variables (absolute changes in lipid levels). A probability (P) value of less than.05 was considered statistically significant. Data Analysis Treatment to goal was defined according to the NCEP ATP III guidelines (LDL-C G100. Patients were included in the analysis if they had pre and post lipid panel. Patients were considered to be on a LAA if they were on any of the following classes of medication at enrollment: statins, fibrates, niacin, bile acid sequestrants, or ezetimibe. A change in LAA was assigned to participants if a new LAA class was added, if there was an increase of a current LAA, or if there was a conversion from one LAA to another. Only participants RESULTS All patients included in the analysis for this study had LDL-C levels Q100 mg/dl at entry to CR. Shown in Table 1 are the demographic and clinical characteristics of the control and intervention cohorts. Both cohorts were primarily male Caucasians referred to CR after either surgical or percutaneous revascularization procedures. There were no significant differences in risk factors between the 2 groups (hypertension, P =.07; diabetes, P =.21; BMI 930, P =.35; tobacco, P =.38). The mean time in CR program was similar for both Systematic Approach to Improve Lipids / 357

4 Table 1 & DEMOGRAPHIC, COMORBID, AND CR INDICATIONS IN CONTROL AND INTERVENTION COHORTS WITH LDL-C LEVELS Q100 mg/dl AT ENTRY TO CARDIAC REHABILITATION Variable Age (years), mean (SD) Control (n = 178) Intervention (n = 67) P 65 (11.5) 66.6 (11).33 Male (%) 128 (71.9) 55 (82).10 Female (%) 50 (28.1) 12 (17.9).06 Diabetes (%) 30 (16.9) 16 (23.9).21 Hypertension (%) 128 (71.9) 40 (59.7).07 BMI Q30 (%) 68 (38.2) 30 (44.8).35 Tobacco (%) 20 (11.2) 5 (7.5).38 Caucasian (%) 156 (87.6) 59 (88.1).93 CABG (%) 92 (51.7) 34 (50.8).89 PTCA (%) 66 (37) 30 (44.8).27 MI (%) 7 (3.9) 1 (1.5).34 CAD (%) 13 (7.3) 2 (3).21 BMI (kg/m 2 ) indicates body mass index; CABG, coronary artery bypass grafting; PTCA, percutaneous transluminal coronary angioplasty; MI, myocardial infarction; CAD, coronary artery disease. cohorts (control: 10.9 T 0.95 weeks vs intervention: 10.8 T 1.1 weeks, P =.61). The average age for the control cohort was 65 years T 12 and 66.6 years T 11 for the intervention cohort (P =.33). Table 2 compares medications at the start of CR for both cohorts. There was no significance difference at entry to CR for angiotensin-converting enzyme inhibitors/angiotensin receptor blockers, aspirin, and coumadin between the 2 groups. There was, however, a statistical difference for beta blockers, plavix, and LAA when comparing the control and intervention cohorts (beta blockers 64.6% vs 82.1%, P =.008; plavix 26.3% vs 50.8%, P =.003; LAA 73.1% vs 85.1%, P =.05). These trends may be due to hospital-based quality improvement programs implemented between control and intervention cohorts. Table 2 & MEDICATIONS ON ENTRY TO CARDIAC REHABILITATION Medication Control (n = 178) Intervention (n = 67) P ACE-I or ARB (%) 94 (53.7) 38 (56.7).67 Beta Blocker (%) 113 (64.6) 55 (82.1).008 LAA (%) 128 (73.1) 57 (85.1).05 Aspirin (%) 146 (83.4) 62 (92.5).07 Plavix (%) 46 (26.3) 34 (50.8).0003 Coumadin (%) 30 (17.1) 12 (17.9).88 ACE-I indicates angiotensin-converting enzyme inhibitors; ARB, angiotensin II receptor blockers; LAA, lipid-altering agent. Table 3 & CONTROL AND INTERVENTION COHORTS: CLINICAL VARIABLES AT ENTRY TO CARDIAC REHABILITATION Variable Control Intervention P (t test) TC (mean T SD, LDL-C (mean T SD, HDL-C (mean T SD, TG (mean T SD, T T T T T T T T BMI (mean T SD) 29.6 T T MET* (mean T SD) 6.4 T T SD indicates standard deviation; TC, total cholesterol; LDL-C, low-density lipoprotein cholesterol; HDL-C, high-density lipoprotein cholesterol; TG, triglycerides; MET, metabolic equivalent time. *Control, n = 164; Intervention, n = 65. Table 3 depicts the clinical variables at entry to the CR program for the 2 cohorts. The only significant difference between the cohorts at entry to the program was the LDL-C level (control T 21.7 vs intervention T 18.5, P =.04) and MET level (control 6.4 T 2.4 vs intervention 5.5T2.3, P =.01). As shown in Table 4, both cohorts had improvements in all their lipid parameters at exit from CR. However, the intervention cohort had significantly greater improvements in TC and LDL-C. There was no significant difference in the change in MET level between the 2 cohorts before and after CR (P =.98). However, within each group, there was an improvement in MET level before and after CR (control: 6.38 T 2.4 to 8.24 T 2.78, P e.0001; intervention, 5.44 T 2.32 to 7.40 T 2.56, P e.0001). Figure 2 shows the percentage of CR patients at goal on exit from CR in the control and intervention cohorts for LDL-C, HDL-C, TC, and triglyceride levels with the associated statistical significance between the cohorts. Participants in the control cohort were significantly less likely to achieve exit LDL-C goal compared with the intervention cohort (43% vs 67%, P =.001). As shown in Table 4, the control cohort had less decrease in mean LDL-C compared with the intervention cohort (j18.4 mg/dl vs j30.9 mg/dl, P =.004). A patient was also less likely to have a lipid medication change during CR in the control cohort compared with the intervention cohort (29% vs 42%, P =.05, data not shown). There was no significant difference between gender and age (e65 years vs 965 years) in relation to medication changes. However, patients with diabetes were less likely to have a medication change in the control cohort compared with the intervention cohort (11.8% vs 32.1%, P =.03, data not shown). No significant difference was observed 358 / Journal of Cardiopulmonary Rehabilitation 2006;26:355/360

5 Table 4 & CONTROL AND INTERVENTION COHORT: DIFFERENCE IN CLINICAL VARIABLES POST CARDIAC REHABILITATION Variable Control Intervention P (t test) TC (mean % T SD, LDL-C (mean % T SD, HDL-C (mean % T SD, TG (mean % T SD, j21.3 T 36.6 j36.3 T j18.4 T 29.8 j30.9 T T T j21.4 T 90.4 j34.1 T BMI (mean T SD) 29.2 T T MET* (mean % T SD) 1.9 T T *Control, n = 164; Intervention, n = 65. between age (e65 years vs 965 years), gender, or presence of diabetes and achieving an exit LDL-C e100 mg/dl when comparing the 2 groups (data not shown). DISCUSSION Effective control of LDL-C to levels less than 100 mg/dl in patients with preexisting CAD has been demonstrated to reduce subsequent cardiac events through randomized clinical trials. 18,19 Methods of achieving similar rates of control in community settings are of increasing interest. Direct recommendations to PCPs in the CHAMP study resulted in 58% of post MI patients achieving an LDL-C level of less than 100 mg/dl; nursing-driven management of post MI patients demonstrated an increase to 97% in those patients having an LDL-C G3.2 mmol/l. 7,8 We have demonstrated that a fairly simple, physician-directed intervention in a CR population with CAD was associated with a 55.8% relative increase in the percentage of CR participants achieving LDL-C goal on CR exit. This improvement is greater than the response to elevated cholesterol in diabetic patients at 44 separate clinical practices in the United States from 2000 to 2002, where it was noted that 55.9% of patients with LDL-C 9100 mg/dl were not on lipid-altering therapy, and of those not receiving treatment, only 5.6% were started on an LAA during the clinic visit. 14 Use of systematic reminders directed at the PCP during CR can substantially increase the percentage of patients achieving nationally recognized goals. Development of systematic interventions, such as goal-oriented reminders to the PCP, can be deployed in a community setting in a nonthreatening manner. Cardiac rehabilitation programs should be viewed as an ideal time for evaluation and reinforcement of secondary prevention and can serve to function as the coordinator of this care. The objectives of CR/secondary prevention are to prevent disability resulting from coronary disease, limit subsequent coronary events and death, and improve physical, functional, and psychological status. Consistent with this model, a recent review for the AHA/AACVPR has revised the medical directors responsibility in achieving goals in outpatient CR programs. 20 Previous reports have shown barriers to achieving LDL-C goals in a population of patients with significant risk factors for cardiovascular events. 6 These barriers to therapy have included, but are not limited to, time limitations at PCP office visits and high cost of medication with comorbid conditions. In a comprehensive CR program, patients participate 3 times a week for approximately 12 weeks and are followed by an interdisciplinary team. This type of program allows expanded time for patient education on coronary heart disease and risk factors, review of indications for medications, and risk/benefits of compliance and noncompliance. Further research on teamoriented systematic approaches to eliminating these barriers should be designed to assess the impact on both short-term and long-term cardiovascular events. A CR program, monitoring lipid levels and assessing proper response with LAA, can be a way to capture those participants who may not have started an LAA before hospital discharge or are in need of titration to adequate control by their PCP. It is important to initiate CR soon after discharge from the hospital to achieve maximum benefit from the program to initiate the lipid altering intervention. The advantages of this study are that it represents clinical outcomes from a community-based CR program that is generalizable to similar settings; it provides information on the effect of structured intervention focused on improving lipid control in a CR population; and by using an observational design, is cost efficient and timely in a environment requiring increased information about how to affect outcomes in healthcare Figure 2. The percentage of CR patients at goal on exit from CR in the control and intervention cohorts for LDL-C, HDL-C, TC, and triglyceride levels with the associated statistical significance between the cohorts. Systematic Approach to Improve Lipids / 359

6 delivery. The potential weaknesses of this study include the bias introduced by underlying temporal trends in improved lipid control and that observational studies are better at determining association versus cause and effect. The absolute 24% change of patients at LDL-C goal in the intervention group is much higher than trends observed in unaffected populations, lending support to the conclusion that temporal trends alone are not responsible for the increased percentage of patients at goal. A randomized study would more directly link the described intervention and improvement to lipid control. However, the ethical implications of not providing the intervention with the knowledge that only a percentage of patients were at LDL-C goal prior to the intervention, along with the cost, impact the benefits of completing a randomized clinical trial. It is important to note that the analysis presented is based on a large patient population in terms of CR programs and the treatment administered to the cohort was standardized based on the clinical guidelines outlined in our Methods section. Despite these limitations, we believe a successful CR program with a dedicated medical director, along with an interdisciplinary team approach, is important to produce optimal outcomes in these patients. Additional research is indicated to assess whether further improvement in the number of patients to LDL-C goal can be obtained with direct management of lipid-lowering agents by the CR medical directors. References 1. Expert panel on detection, evaluation, and treatment of high blood cholesterol in adults. Summary of the second report of the National Cholesterol Education Program (NCEP) expert panel on detection, evaluation, and treatment of high blood cholesterol in adults (Adult Treatment Panel II). 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