Prevalence of Dietary Supplement Use in Patients with Proven or Suspected Cardiovascular Disease

Table 2

Comparison of results in studies of dietary supplement use in cardiac patients.

Study	Setting	Clinical characteristics of sample	Mean age of sample (SD; range)	% female	Ethnic composition	Prevalence of supplement use	Associations between cardiovascular health, medication and supplement use	Reasons for use	Physician awareness
Ackman et al. (1999) [7]	Hospital clinic	Diagnosed congestive heart failure	69 (−)	37%	—	Vitamins/minerals 59%; Nutritional supplements 17%; Health food/herbal products 38%	Use unrelated to CHF severity	—	—
Ai and Bolling (2002) [8]	Cardiac clinic	Admitted for non-emergency/non-transplant surgery	62.4 (36–84)	44%	—	Megavitamins 13%; Herbs and folk remedies 12%; Homeopathy 4%	—	—	—
Albert et al. (2009) [9]	Hospitals and cardiology practices	Diagnosed heart failure	69.6 (±13.1; 31–98)	37%	81% Caucasian	Multivitamins/minerals 36%; Herbal therapy 12%; 60% users take with prescription medication	Users more likely than nonusers to be under cardiologist care, have high cholesterol, diabetes but not significantly different ejection fraction	Promote or maintain good health 45%–47%; Overall wellbeing 30%–42%; Energy/decrease fatigue 13%–25%	—
Amira and Okubadejo (2007) [10]	Hypertension clinic	Diagnosed hypertension	55.1 (±12.4)	60%	—	Dietary supplements and herbs 97%	Users had higher BMI (29 versus 27) but no different on blood pressure readings or duration of hypertension. Users no different on medication compliance and blood pressure control	—	—
Artz et al. (2006) [11]	Community	Taking nonprescription medication for cardiac reason	—	69%	—	Vitamin/mineral supplement 38%; Nonvitamin/mineral supplement 21%	36% vitamin/mineral supplement users and 16% other supplement users also take prescription cardiac medication	—	—
Barraco et al. (2005) [12]	Hospital cardiology unit	Suspected acute coronary syndrome	66.2 (±13.4)	39%	79% Caucasian, 13% African-American	Herbals 5%; Anti-oxidants 4%; Minerals 3%	—	—	—
Buettner et al. (2007) [13]#	Community	Self-reported CAD/stroke or hypertension/high cholesterol	CAD/stroke 66 (−); hypertension/high cholesterol 58 (−)	46%/57%	80%/78% White, 10%/10% Black, 3%/4% Mexican-American	Multivitamin 36%–40%; Minerals 9%–11%; Herbs 7%–10%; Other supplements 6%-7%; Of cardiac medication users: Multivitamin 36%–40%; Minerals 25%–30%; Herbs 6%–9%; Other supplements 6%-7%	Of those taking medication for cardiovascular disease, 63% of those with previous CAD/stroke and 64% of those with hypertension/high cholesterol also used a supplement; CAD/stroke group more likely to use vitamin E, B vitamins and less likely to use fish oil; hypertension/high cholesterol group more likely to use garlic and ginseng	—	—
Chagan et al. (2005) [14]	Hospital clinic	Diagnosed cardiovascular disease	users 61.4 (±16.7); nonusers 58.7 (±16.3)	40%	50% White, 23% African-American, 15% Hispanic, 12% other	“Biological-based therapy”: ever used 48%, used in last 12 months 42%	No difference in users and nonusers in number of cardiovascular diseases. Average of 2 supplements and 7 prescription medications used per patient.; 42 potential interactions identified, most commonly aspirin and vitamin E in 16 patients	18 of 42 supplements taken for a cardiac reason; 75% users perceive safe, 70% effective, 45% believe cause fewer side effects than prescription medication	40% physicians unaware; 67% of users were not asked by physicians about use
Dal Corso et al. (2007) [15]	Outpatient heart failure clinic	Clinic patients	65.7 (±10)	11%	—	Vitamins/minerals 21%; Herbal medicine 9%	Only 1 patient from 153 reduced and interrupted heart failure tablets	—	39% did not report herbal use to doctors; 44% did not report vitamin/mineral use
Gohar et al. (2008) [16]	Outpatient hypertension clinic	Clinic patients	57.3 (±16)	46%	64% White European, 25% South Asian, 11% Afro-Caribbean	Any biological-based therapy 29%; Vitamin supplements 20%; Dietary supplements 11%; Herbal medicine 7%	—	—	—
Krasuski et al. (2006) [17]	Outpatient cardiology clinic	Returning clinic patients	66.2 (±11.6)	32%	—	Multivitamins 68%	No difference between users and nonusers on use of aspirin, betablockers, ACE-inhibitors, statins or Coumadin	Greater benefit than prescription 15%, safer than prescription 45%, no interactions 47%	50% did not inform cardiologists
Liu et al. (2000) [18]	Cardiothoracic surgery clinic	Patients attending clinic	41% aged 40–65,; 51% aged over 65	28%	76% White, 7% African American, 6% Hispanic, 6% Native American	Vitamins 54%; Herbs 10%; Homeopathy 3%	—	—	—
Pharand et al. (2003) [19]	Hospital ward, outpatient clinic and emergency room	Diagnosed with CHF or CAD for at least 6 months	66 (40% over 70)	41%	—	Multivitamin/mineral 23%; Single-entity; vitamin/mineral 38%; Herbal product 17%	—	—	—
Shafiq et al. (2003) [20]	Hospital hypertension clinic	Patients attending clinic	71% aged over 50,; 26% aged 36–50,; 3% aged 18–25	26%	—	Ayurveda 57%; Herbal medicine 14%; Homeopathy 8%	—	Adverse reactions of conventional therapy 59%; Recommended by family/friends 62%	5% informed; doctors about CAM
Stys et al. (2004) [21]	Preventive cardiology clinic	Patients attending clinic	61 (±14)	28%	—	Vitamins 53%; Herbs 21%; 1 or more supplements 57% Average of 3 supplements per user	Users more likely to have established CAD, family history of premature CAD, higher total cholesterol, higher HDL and use statins; Users and nonusers have similar blood pressure and HbA1c levels	—	—
Wong et al. (2003) [22]	Warfarin clinic	Patients attending clinic	Users 56.5 (±12.4); Nonusers 56.4 (±11.7)	59%	—	Herbal medicine 26%	INR for users lower than for nonusers; No difference between herbal users and nonusers in indication for Warfarin, duration of Warfarin therapy or Warfarin dosage	—	—
Wood et al. (2003) [23]	Registry of patients with cardiovascular disease	Previously hospitalised with ischaemic heart disease, CHF or AF	64.3 (±11.9)	35%	—	Megadose vitamins 35%; Herbal supplements 32%; Non-herbal supplements 22%	Of 24 patients taking warfarin, amiodarone, sotalol, or digoxin, 50% also used vitamin, 36% herbal, 36% non-herbal supplement	Potential improvement in condition 57%, proven benefit 28%, dissatisfied with conventional treatment 17%	—
Yeh et al. (2006) [6]	Community	Self-reported cardiovascular disease	35% aged 65 and over; 31% aged 50–64	53%	82% White, 13% Black, 5% other	High-dose vitamins 3%; Herbal therapies 18%	Similar rates of vitamin and herbal use in those with and without cardiovascular disease	80% herbal users perceived herbs to be helpful	56% did not disclose herbal use
Yilmaz et al. (2007) [24]	Outpatient cardiology clinic	Admitted to clinic	males 54.7 (±13.3),; females 56.2 (±14.7)	46%	—	Herbals 39%; Of users: 55% used daily with average duration of 39 months (±70 months)	Users and nonusers were similar on diabetes, smoking, prior MI and prior PCI	19% used for hypertension, 23% for high cholesterol	92% did not inform physicians
Zick et al. (2005) [25]	Heart failure clinic	Diagnosed congestive heart failure	57 (±10)	33%	—	Any supplement 33%	82% used supplement for cardiac problem: 62% for CHF, 13% angina, 6% for hypertension		—

Note: —: not reported, NA: not applicable, #Study examined CAD/stroke and hypertension/hypercholesterolaemia groups separately and 2 figures are presented, one for each group.