Use of Complementary Therapies in Cardiovascular Disease

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1 Use of Complementary Therapies in Cardiovascular Disease Kavita Prasad, MD a, *, Varun Sharma, MD a, Kandace Lackore, BS b, Sarah M. Jenkins, MS b, Abhiram Prasad, MD c, and Amit Sood, MD a The aim of the present study was to assess the use of complementary and alternative medicine (CAM) treatments in outpatients with cardiovascular disease and their interest in future use. The increasing popularity of CAM therapies highlights the need to explore their use among patients with cardiovascular disease. Data were collected with a prospective, point-of-care, anonymous, 17-question survey about basic medical information and previous use and interest in the future use of dietary supplements and other CAM interventions among patients undergoing outpatient cardiology evaluation at a Midwestern tertiary care center. The survey was completed by 1,055 patients (655 men, 351 women; mean age 63.5 years) of whom 98.1% were white. Of these, 36.8% had cardiac symptoms for >10 years, 48.2% had coronary artery disease, and 82.5% reported use of CAM therapies. Of these patients, 75.4% reported using dietary supplements, 31.5% chiropractic therapy, 23.9% mind-body therapies, and 19.2% massage. Only 14.4% had discussed the use of CAM treatments with their physicians. The top 4 treatments used for cardiac symptoms were relaxation techniques, stress management, meditation, and guided imagery. Also, 48.6% were interested in participating in a future clinical trial of an alternative treatment. The great majority of patients seen in current practice use CAM therapies, and a large proportion expressed an interest in participating in research with CAM therapies. In conclusion, research directed with an integrative approach to cardiovascular care might prove beneficial when designing future studies. Ó 2013 Elsevier Inc. All rights reserved. (Am J Cardiol 2013;111:339e345) The definition of complementary and alternative medicine (CAM) has continued to evolve. As defined by the National Center of Complementary and Alternative Medicine, CAM is a group of diverse medical and healthcare systems, practices, and products that are not generally considered part of conventional medicine. 1 The 5 categories or domains of CAM as classified by the National Center of Complementary and Alternative Medicine are whole medical systems (e.g., homeopathy, ayurvedic medicine), mind-body interventions (e.g., yoga, tai chi, meditation, qigong, biofeedback, hypnotherapy), biologically based therapies (e.g., herbal treatments, megadose vitamins), manipulative and bodybased methods (e.g., chiropractic therapy), and energy therapies (e.g. Reiki, magnetic therapy). CAM has become increasingly popular in the United States during the past few years. According to a Centers for Disease Control survey in 2007 involving >31,000 patients, almost 40% of adults had used CAM therapies in the previous 12 months. 2 Increasingly, dietary supplements and other CAM treatments are marketed over the counter to reduce the risks and symptoms of cardiovascular disease (CVD). In addition, patients with CVD might be more likely a Division of General Internal Medicine, Mayo Clinic, Rochester, Minnesota; b Division of Biomedical Statistics and Informatics, Mayo Clinic, Rochester, Minnesota; and c Division of Cardiovascular Diseases, Mayo Clinic, Rochester, Minnesota. Manuscript received July 30, 2012; revised manuscript received and accepted October 11, See page 344 for disclosure information. *Corresponding author: Tel: (507) ; fax: (507) address: prasad.kavita@mayo.edu (K. Prasad). to seek CAM treatments to decrease the psychological stress associated with this condition. The proportion of patients with CVD using these treatments has been reported in several studies. 3e8 However, the data are often reported only for a specific subset of patients (e.g., patients with acute coronary syndrome) 4,5,9 or specific interventions (e.g., patients with coronary artery disease practicing mind-body interventions). 5 Furthermore, the proportion of patients with CVD interested in the future use of CAM treatments and the type of interventions preferred by these patients is not yet known. The present study explored, in a point-of-care survey, the proportion of patients with CVD reporting current and/or previous use of CAM treatments. We also evaluated patients attitudes toward the future use of CAM treatments. Methods The present cross-sectional, point-of-care survey was conducted with patients attending the Cardiology Outpatient Clinic at Mayo Clinic in Rochester, Minnesota, from March 2009 to October The survey was administered before the clinic consultation. Because the survey did not collect any personal identifiers, no informed consent was obtained. Consent was considered implied by the participant s completion and return of the survey. The Mayo Clinic institutional review board approved the study protocol. Patients were included if they were attending an outpatient cardiology appointment; willing and able to participate in the survey; and able to speak, read, and understand the English language. No specific exclusions were used /12/$ - see front matter Ó 2013 Elsevier Inc. All rights reserved.

2 340 The American Journal of Cardiology ( Table 1 Baseline clinical characteristics Characteristic Overall (n ¼ 1,055) Men (n ¼ 655) Women (n ¼ 351)* p Value Age (yrs) 0.09 Mean SD Range 5.0e e e99.0 Race 0.35 White 972 (98.1%) 632 (98.3%) 337 (97.7%) Black 3 (0.3%) 3 (0.5%) 0 American Indian/Alaskan native 9 (0.9%) 5 (0.8%) 4 (1.2%) Asian 6 (0.6%) 3 (0.5%) 3 (0.9%) Native Hawaiian/other Pacific Islander 1 (0.1%) 0 1 (0.3%) Heart-related symptom duration (yrs) 0.02 <1 175 (17.6%) 118 (18.8%) 51 (15.7%) 1e3 185 (18.6%) 105 (16.7%) 68 (20.9%) 4e5 105 (10.5%) 58 (9.2%) 41 (12.6%) 6e (16.5%) 97 (15.4%) 62 (19.1%) > (36.8%) 251 (39.9%) 103 (31.7%) Angina pectoris 163 (16.2%) 94 (14.8%) 63 (19.2%) 0.02 Sublingual nitroglycerin tablet use 164 (16.2%) 105 (16.7%) 55 (16.3%) 0.98 Previous coronary angiography 465 (46.4%) 312 (49.4%) 129 (39.1%) Angioplasty or heart stents placed 271 (58.3%) 198 (63.5%) 60 (46.5%) Previous heart bypass surgery 197 (20.2%) 154 (24.9%) 34 (10.8%) <0.001 Coronary artery disease 507 (48.2%) 341 (52.1%) 139 (39.8%) <0.001 Currently smoke cigarettes 43 (4.3%) 27 (4.1%) 16 (4.6%) 0.74 Discussed use of alternative treatments with physician 135 (14.4%) 78 (12.7%) 57 (17.6%) 0.04 Interested in participating in clinical trial 471 (48.6%) 302 (47.3%) 166 (50.9%) 0.28 Diagnosed medical conditions (most to least common overall) High blood pressure 606 (57.4%) 374 (57.1%) 199 (56.7%) 0.90 High cholesterol 544 (51.6%) 343 (52.4%) 173 (49.3%) 0.35 Acid reflux 301 (28.5%) 176 (26.9%) 114 (32.5%) 0.06 Heart attack 241 (22.8%) 174 (26.6%) 53 (15.1%) <0.001 Diabetes 187 (17.7%) 120 (18.3%) 59 (16.8%) 0.55 Heart failure 175 (16.6%) 116 (17.7%) 53 (15.1%) 0.29 Angina pectoris 166 (15.7%) 114 (17.4%) 47 (13.4%) 0.10 Stroke 95 (9.0%) 61 (9.3%) 33 (9.4%) 0.96 Lung disease 92 (8.7%) 58 (8.9%) 33 (9.4%) 0.77 Coronary spasm 45 (4.3%) 25 (3.8%) 19 (5.4%) 0.24 Total diagnosed conditions (n) Median (IQR) 2 (1e3) 2 (1e3) 2 (1e3) Range 0e9 0e9 0e8 IQR ¼ interquartile range. * Data not provided by 49 participants for gender. Men versus women. A diagnosis of coronary artery disease was implied if 1 of the following 5 questions were checked: 1. Do you suffer from angina pectoris? 2. Have you had an angioplasty? 3. Have you had heart stents placed? 4. Do you have chest pain for which you take nitroglycerin tablets under your tongue? 5. Have you ever had heart bypass surgery? The study questionnaire was developed in collaboration with the Survey Research Center at the Mayo Clinic. This was a 17-question, paper-and-pencil survey distributed by the desk staff as patients checked in for their cardiology appointment. The participants were given the survey form while waiting for their appointment and were instructed to complete it and return it to the receptionist any time before leaving the clinic. The anonymous, consecutive survey obtained information on demographic characteristics, CVD history, current CAM use, and attitudes toward the future use of CAM therapies for heart-related symptoms. CAM use was stratified into dietary supplements and other CAM modalities. The survey instrument required approximately 15 to 20 minutes to complete. The response categories varied, depending on the specific question asked. The data were summarized using frequency distribution tables stratified by gender for all categorical variables. The Fisher exact test or chi-square test was used to compare the categorical data between the 2 groups. p Values <0.05 were considered statistically significant. Results Of the 1,055 patients surveyed, 655 (65%) were men and 351 (35%) were women (Table 1). No difference was seen in age of the men and women who completed the survey. Virtually all the participants (98.1%) were white. Of those

3 Coronary Artery Disease/CAM in Cardiovascular Disease 341 Table 2 Use of dietary supplements Dietary Supplement Any Use (n ¼ 1,055) Previously for Heart Symptoms (n ¼ 1,055) Currently for Heart Symptoms (n ¼ 1,055) Multivitamin 557 (52.8%) 54 (5.1%) 64 (6.1%) Fish oil 477 (45.2%) 158 (15.0%) 213 (20.2%) Vitamin C 381 (36.1%) 40 (3.8%) 28 (2.7%) Vitamin E 306 (29.0%) 53 (5.0%) 19 (1.8%) Fiber 286 (27.1%) 32 (3.0%) 43 (4.1%) Omega 3 fatty acids 244 (23.1%) 81 (7.7%) 72 (6.8%) Folic acid 193 (18.3%) 63 (6.0%) 47 (4.5%) Coenzyme Q (11.8%) 42 (4.0%) 40 (3.8%) Garlic 123 (11.7%) 31 (2.9%) 14 (1.3%) Soy 73 (6.9%) 13 (1.2%) 7 (0.7%) Gingko biloba 57 (5.4%) 7 (0.7%) 2 (0.2%) b Carotene 52 (4.9%) 16 (1.5%) 7 (0.7%) L-Arginine 40 (3.8%) 15 (1.4%) 7 (0.7%) Ginseng 39 (3.7%) 6 (0.6%) 2 (0.2%) Benecol 27 (2.6%) 11 (1.0%) 7 (0.7%) Hawthorn 13 (1.2%) 8 (0.8%) 2 (0.2%) Horse chestnut 4 (0.4%) 1 (0.1%) 0 Data are presented as number of patients (%). Figure 1. Use of dietary supplements. Frequency of use of 17 dietary supplements for heart-related symptoms among outpatients attending a cardiology clinic. surveyed, 367 (36.8%) had heart-related symptoms for >10 years, with 163 (16.2%) reporting current symptoms of angina pectoris requiring the use of sublingual nitroglycerin. A diagnosis of coronary artery disease was reported by 507 participants (48.2%), and 43 patients (4.3%) were current smokers. Of those surveyed, 57.4% of patients had coexisting hypertension, 51.6% had hyperlipidemia, and 28.5% had a diagnosis of gastroesophageal reflux disease. The duration of cardiac symptoms and a history of coronary artery disease, myocardial infarction, angiography, or revascularization were greater for the men. Overall, 863 patients (81.8%) reported previous use of CAM therapies. Of these, 466 participants (44.2%) reported the use of CAM therapies for heart-related symptoms. The use of dietary supplements was reported by 795 participants (75.4%), and the use of CAM approaches other than dietary supplements was reported by 550 (52.1%). Of those surveyed, 252 (23.9%) reported using mind-body therapy. The top 5 dietary supplements used were multivitamins (52.8%), fish oil (45.2%), vitamin C (36.1%), vitamin E (29.0%), and fiber (27.1%; Table 2). The top supplements used for heart-related conditions were fish oils, omega 3 fatty acids, multivitamins, folic acid, coenzyme Q10, and vitamin E (Figure 1). The top 4 CAM modalities other than dietary supplements were chiropractic therapy (31.5%), massage (19.2%), relaxation techniques (12.6%), and stress management

4 342 The American Journal of Cardiology ( Table 3 Use of alternative therapies Treatment Any Use (n ¼ 1,055) Previously for Heart Symptoms (n ¼ 1,055) Currently for Heart Symptoms (n ¼ 1,055) Chiropractic therapy 332 (31.5%) 10 (0.9%) 3 (0.3%) Massage 203 (19.2%) 4 (0.4%) 5 (0.5%) Relaxation 133 (12.6%) 34 (3.2%) 29 (2.7%) Stress management 108 (10.2%) 31 (2.9%) 28 (2.7%) Meditation 100 (9.5%) 28 (2.7%) 20 (1.9%) Acupuncture 96 (9.1%) 6 (0.6%) 5 (0.5%) Yoga 67 (6.4%) 4 (0.4%) 4 (0.4%) Guided imagery 58 (5.5%) 19 (1.8%) 5 (0.5%) Biofeedback 43 (4.1%) 3 (0.3%) 2 (0.2%) Hypnosis 38 (3.6%) 1 (0.1%) 0 Acupressure 32 (3.0%) 4 (0.4%) 3 (0.3%) Reflexology 32 (3.0%) 2 (0.2%) 2 (0.2%) Tai chi 32 (3.0%) 5 (0.5%) 5 (0.5%) Homeopathy 28 (2.7%) 5 (0.5%) 2 (0.2%) Magnetic therapy 21 (2.0%) 3 (0.3%) 0 Naturopathy 8 (0.8%) 1 (0.1%) 0 Ayurvedic treatment 7 (0.7%) 1 (0.1%) 2 (0.2%) Data are number of patients (%). Figure 2. Use of mind-body alternative treatments. Frequency of use of 8 mind-body therapies for any reason (Left) and heart-related symptoms (Right) among outpatients attending a cardiology clinic. techniques (10.2%; Table 3). For heart-related symptoms, the top 4 CAM treatments used were relaxation programs (4.5%), stress management (4.4%), meditation (3.1%), and guided imagery (2.2%). Among patients using mind-body therapies, the most popular approaches used were relaxation techniques (12.6%), stress management (10.2%), and meditation (9.5%; Figure 2). The most common heart-related symptoms for which patients reported using CAM treatments were shortness of breath, palpitations, chest pain, dizziness, and leg swelling. Of the patients using CAM therapy for heart-related symptoms, the greatest benefit was reported for palpitations (22.2%), sleep disturbance (21.8%), chest pain (20.0%), and leg swelling (19.4%; Table 4). Among patients with coronary artery disease, the greatest benefit was reported for chest pain (20.0%), sleep disturbance (17.9%), leg swelling (17.9%), and shortness of breath (13.9%). Among those without coronary artery disease, the greatest benefit was reported for palpitations (32.8%), sleep disturbance (26.3%), leg swelling (25.0%), and shortness of breath (24.1%). Only 135 of the respondents (14.4%) reported discussing the use of alternative treatments with their physician. Of the patients surveyed, 471 (48.6%) reported a future interest in participating in a clinical trial assessing alternative therapies in healthcare. The participants were most interested in trying massage, weight loss programs,

5 Coronary Artery Disease/CAM in Cardiovascular Disease 343 Table 4 Perceived efficacy of complementary and alternative medicine Patients (n) Improved Worsened No Change p Value* Chest pain 0.46 Overall (20.0%) 8 (7.0%) 84 (73.0%) Men (21.2%) 3 (4.5%) 49 (74.2%) Women 47 9 (19.1%) 5 (10.6%) 33 (70.2%) Shortness of breath 0.83 Overall (18.2%) 8 (5.8%) 104 (75.9%) Men (17.5%) 4 (5.0%) 62 (77.5%) Women (18.5%) 4 (7.4%) 40 (74.1%) Palpitations 0.03 Overall (22.2%) 6 (4.8%) 92 (73.0%) Men (16.4%) 1 (1.5%) 55 (82.1%) Women (29.3%) 5 (8.6%) 36 (62.1%) Dizziness 0.29 Overall (17.0%) 6 (5.4%) 87 (77.7%) Men 65 8 (12.3%) 4 (6.2%) 53 (81.5%) Women (23.4%) 2 (4.3%) 34 (72.3%) Symptoms of fainting 0.43 Overall (14.1%) 1 (1.4%) 60 (84.5%) Men 44 6 (13.6%) 0 38 (86.4%) Women 27 4 (14.8%) 1 (3.7%) 22 (81.5%) Leg swelling 0.60 Overall (19.4%) 0 75 (80.6%) Men (21.1%) 0 45 (78.9%) Women 36 6 (16.7%) 0 30 (83.3%) Sleep disturbance 0.20 Overall (21.8%) 2 (1.6%) 95 (76.6%) Men (20.5%) 0 58 (79.5%) Women (23.5%) 2 (3.9%) 37 (72.5%) Data are presented as n (%). * Men versus women. Figure 3. Future use of alternative treatments. Percentage of patients interested in using a variety of alternative therapies in the future. relaxation techniques, multivitamins, or stress management programs to help with heart-related symptoms (Figure 3). Discussion The major findings of the present study, a point-of-care survey of 1,055 patients attending an outpatient cardiology clinic, were that 81.8% of the respondents reported using CAM modalities, with 75.3% of the respondents reporting using dietary supplements and 23.9% reporting using mindbody therapies. Of these, nearly half were using CAM treatments for their heart-related symptoms. Nearly half of the patients interviewed reported a future interest in participating in a clinical trial assessing alternative therapies in healthcare.

6 344 The American Journal of Cardiology ( Several previous studies have evaluated the prevalence of use of CAM interventions in patients with CVD. A crosssectional survey of 3,128 adults showed that 10% of subjects self-reported taking 1 nonprescription medications for a perceived cardiovascular health purpose. 3 In a smaller study involving a telephone survey of 107 patients with CVD, 64% of patients reported the use of CAM products for a cardiovascular condition. 7 The 2002 National Health Interview Survey followed up 10,572 patients with CVD and found CAM use was 36% in this subset of patients. 8 Using data from the National Health Interview Survey, adults with CVD reported CAM use to be 46.4%, similar to that found in our study. 6 In a study involving patients with acute coronary syndrome, 35% of patients had practiced mind-body therapies in their lifetime, with 25.4% currently practicing. 5 A 19% prevalence of CAM use in patients with coronary artery disease was observed in hospitalized patients with acute coronary syndromes. 4 The greater prevalence of CAM use in our study could be reflective of more advanced disease and a greater complexity of underlying illness among patients seen at a tertiary care center. Our finding is consistent with previous surveys at our institution reporting greater CAM use in our patients compared to the national average. 10,11 Moreover, the survey findings are consistent with previous studies that dietary supplements are among the most commonly used CAM modalities in patients with CVD. 8,9 The products that have been tested for cardiovascular indications and are commonly used by these patients include fish oil, coenzyme Q10, garlic, Gingko biloba, hawthorn (Cratageus), guggulipid (guggul gum), horse chestnut (Aesculus hippocastanum), L-carnitine, L-arginine, oleander (Nerium oleander/thevetia peruviana), red yeast rice (Monascus purpureas), and policosanol. We found the use of multivitamins, fish oils, vitamin C, and vitamin E to be the greatest in this group of patients. Fish oil supplements have become largely accepted as a part of the treatment regimen for elevated serum triglycerides and the maintenance of vascular wall health. This was supported by our survey result of 30% of respondents reporting fish oil use as a part of therapy for CVD. However, not all supplement use has been supported by evidence. For example, the efficacy of vitamin E, used by 29% of our patients, has not been supported by evidence, with meta-analyses concluding that high-dose vitamin E supplementation might increase morbidity and all-cause mortality. The high proportion of patients reporting the use of dietary supplements in our study, combined with the very small proportion self-reporting their use of CAM to their physicians, argues in favor of a careful review of dietary supplements during cardiology consultations because of the potential for interactions between the dietary supplements and common cardiac medications. 12 In contrast to dietary supplements, mind-body approaches, which have minimal side effects, were used by only 24% of the participants. Relaxation, stress management, and meditation use ranged from 9% to 12% of survey respondents for any disease; for CVD specifically, only 3% to 5% of the respondents used these treatments. This might reflect the lack of availability of these services and that our study had a greater proportion of men, who tend to use less CAM overall, especially mind-body therapies. For example, yoga has been shown to lower blood pressure, improve physical fitness, and increase absolute and relative maximum oxygen uptake by 7% and 6%, respectively, after 8 weeks in a controlled setting. 13,14 Qigong, an energybased modality, improved the respiratory rate and heart rate in 76 patients after myocardial infarction. 15 In another study testing qigong, hospitalization was reduced in post myocardial infarction patients learning qigong relaxation techniques. 13 Several styles of meditation have been tested and found to reduce blood pressure, improve heart rate variability, slow the respiratory rate, and, even, provide survival benefit. 16e25 A perceived improvement was reported by approximately 1 in 5 patients for symptoms, including chest pain, shortness of breath, palpitations, leg swelling, and sleep disturbances (Table 4). These are common cardiac symptoms that can be a challenge to manage if they persist despite maximum medical therapy and CVD intervention. This is where CAM modalities might complement the treatment of CVD symptoms refractory to standard medical therapy or in cases in which drug side effects are not tolerable. Additional studies of CAM treatment are needed to explore their efficacy for the management of chronic symptoms related to CVD. Nearly half of the survey respondents indicated an interest in participating in a future CAM clinical trial related to their heart disease. Many respondents also indicated they would like to incorporate CAM therapy as a part of their current CVD treatment regimen. The greatest interest was observed for massage, weight loss programs, relaxation techniques, multivitamins, and stress management programs (Figure 3). Efforts to educate healthcare providers about the availability of low-cost, relatively safe, and efficacious CAM modalities might help better serve the needs of patients. The strengths of the present study included the large sample size and a relatively homogeneous population. Because the survey was given to patients from a tertiary care center, excluding community-based practices, the generalizability of our findings might be limited. Nevertheless, the results of the present study can be extrapolated to patients with CVD seeking care at a tertiary care center. Supplementary data Supplementary data related to this article can be found at Disclosures The authors have no conflicts of interest to disclose. 1. National Center for Complementary and Alternative Medicine. What is complementary and alternative medicine? Available at: nih.gov/health/whatiscam. Accessed February 6, Barnes PM, Powell-Griner E, McFann K, Nahin RL. Complementary and alternative medicine use among adults: United States, Adv Data 2004:1e Artz MB, Harnack LJ, Duval SJ, Armstrong C, Arnett DK, Luepker RV. Use of nonprescription medications for perceived cardiovascular health. 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