Natural Health Product Utilization in Warfarinized Children;Prevalence and Knowledge

Abstract

Background:

The need for long-term thromboprophylaxis in children using warfarin therapy is increasing. Natural health products (NHPs) are administered to children by parents who perceive them to be useful and acceptable adjuncts or alternatives to conventional therapies. Interactions of NHPs with prescribed therapies may result in serious adverse events. NHP usage is underevaluated in children and there are no studies evaluating NHP usage in warfarinized children.

Objectives:

To explore NHP use in warfarinized children and their siblings to determine the prevalence, varieties, and reasons for NHP usage, as well as the potential effect on warfarinization (eg, time in therapeutic range [TTR]).

Methods:

This is a 3-phase cross-sectional cohort study that includes the (1) prevalence (2) NHP education and knowledge assessment, and (3) the follow-up NHP utilization phase.

Results:

Forty-six percent of warfarinized children consumed NHPs, with time in therapeutic range of 74%. The mean score for baseline knowledge of NHPs and warfarin following the education phase was 67%. Follow-up NHP use was 30%, and increased consistency of utilization with TTR was 83% (p < 0.05), consistent with education provided.

Conclusions:

The consistent prevalence rates over time of NHP usage in warfarinized children indicate the need for future studies. Education remains vital to combat the potential risks of NHP-warfarin interaction, encouraging patient disclosure and consistency.

References

Monagle

Chan

AKC

Goldenberg

. Antithrombotic therapy in neonates and children: Antithrombotic therapy and prevention of thrombosis, 9th ed.: American College of Chest Physicians Evidence-Based Clinical Practice Guidelines. Chest 2012; 141 (2 suppl): e737S–801S.

Streif

Andrew

Marzinotto

. Analysis of warfarin therapy in pediatric patients: A prospective cohort study of 319 patients. Blood 1999; 94: 3007–14.

Newall

Monagle

Johnston

. Home INR monitoring of oral anticoagulant therapy in children using the CoaguChek, S point-of-care monitor and a robust education program. Thromb Res 2006; 118: 587–93.

Phillips

Ansell

. Outpatient management of oral vitamin K antagonist therapy: Defining and measuring high-quality management. Expert Rev Cardiovasc Ther 2008; 6: 57–70.

Schmitt

Speckman

Ansell

. Quality assessment of anticoagulation dose management: Comparative evaluation of measures of time-in-therapeutic range. J Thromb Thrombolysis 2003; 15: 213–6.

Jean

Cyr

. Use of complementary and alternative medicine in a general pediatric clinic. Pediatrics 2007; 120: e138–e141.

Ernst

. Complementary medicine: Common misconceptions. J R Soc Med 1995; 88: 244–7.

Goldman

Rogovik

Lai

Vohra

. Potential interactions of drug-natural health products and natural health products-natural health products among children. J Pediatr 2008; 152: 521–6. e524.

Cuzzolin

Zaffani

Murgia

. Patterns and perceptions of complementary/alternative medicine among paediatricians and patients' mothers: A review of the literature. Eur J Pediatr 2003; 162: 820–7.

10.

Foster

Arnason

Briggs

. Natural health products and drug disposition. Annu Rev Pharmacol Toxicol 2005; 45: 203–26.

11.

Foster

Vandenhoek

Tang

Budzinski

Krantis

. Effect of several Chinese natural health products of human cytochrome P450 metabolism. J Pharm Pharm Sci 2002: 5:185–185.

12.

Lee

Andrade

ASA

Flexner

. Interactions between natural health products and antiretroviral drugs: Pharmacokinetic and pharmacodynamic effects. Clin Infect Dis 2006; 43: 1052–9.

13.

Singh

Levine

MAH

. Potential interactions between pharmaceuticals and natural health products in Canada. J Clin Pharmacol 2007; 47: 249–58.

14.

Vohra

Cohen

. Ethics of complementary and alternative medicine use in children. Pediatr Clin North Am 2007; 54: 875–84;x.

15.

Vohra

Moher

. Complementary and alternative medicine in Canadian children: A call for action. Paediatr Child Health 2005; 10: 154–6.

16.

Ansell

McDonough

Zhao

Harmatz

Greenblatt

. The absence of an interaction between warfarin and cranberry juice: A randomized, double-blind trial. J Clin Pharmacol 2009; 49: 824–30.

17.

Vohra

Brulotte

Charrois

Laeeque

. Adverse events associated with paediatric use of complementary and alternative medicine: Results of a Canadian paediatric surveillance program survey. Paediatr Child Health 2009; 14: 385–7.

18.

Wittkowsky

Sekreta

Nutescu

Ansell

. Barriers to patient self-testing of prothrombin time: National survey of anticoagulation practitioners. Pharmacotherapy 2005; 25: 265–9.

19.

Jiang

Blair

EYL

McLachlan

. Investigation of the effects of herbal medicines on warfarin response in healthy subjects: A population pharmacokinetic-pharmacodynamic modeling approach. J Clin Pharmacol 2006; 46: 1370–8.

20.

Smith

LFP

Ernst

Ewings

Myers

Smith

. Co-ingestion of herbal medicines and warfarin. Br J Gen Pract 2004; 54: 439–41.

21.

Shalansky

Lynd

Richardson

Ingaszewski

Kerr

. Risk of warfarin-related bleeding events and supratherapeutic international normalized ratios associated with complementary and alternative medicine: A longitudinal analysis. Pharmacotherapy 2007; 27: 1237–47.

22.

Ansell

. Effects of dietary supplements on hemostasis. Thromb Res 2005; 117: 45–7; discussion 65–7.

23.

Samuels

. Herbal remedies and anticoagulant therapy. Thromb Haemost 2005; 93: 3–7.

24.

Clauson

Santamarina

Buettner

Cauffield

. Evaluation of presence of aspirin-related warnings with willow bark. Ann Pharmacother 2005; 39: 1234–7. DOI 10.1345/aph.1E650

25.

Saw

Bahari

Ang

Lim

. Potential drug-herb interaction with antiplatelet/anticoagulant drugs. Complement Ther Clin Pract 2006; 12: 236–41.

26.

Bauman

Black

Kuhle

. KIDCLOT: The importance of validated educational intervention for optimal long term warfarin management in children. Thromb Res 2009; 123: 707–9.

27.

Rogovik

Vohra

Goldman

. Safety considerations and potential interactions of vitamins: Should vitamins be considered drugs? Ann Pharmacother 2010;44:311–311. DOI 10.1345/aph.1M238

28.

Cheng

. Ginseng and other herbal medicines that interact with warfarin. Int J Cardiol 2005; 104: 227.

29.

Gage

Fihn

White

. Management and dosing of warfarin therapy. Am J Med 2000; 109: 481–8.

30.

Yuan

C-S

Wei

Dey

. Brief communication: American ginseng reduces warfarin's effect in healthy patients: A randomized, controlled trial. Ann Intern Med 2004; 141: 23–7.

31.

Murty

. Postmarket surveillance of natural health products in Canada: Clinical and federal regulatory perspectives. Can J Physiol Pharmacol 2007; 85: 952–5.

32.

Kondro

. Natural health products: New labels, new credibility? CMAJ 2004; 170: 941.

33.

Health Canada: Natural Health Product Regulations, 2012.

34.

Natural health products regulations. Canada Gazette 2003: 137: 1532–607.

35.

Spigelblatt

. Alternative medicine: Should it be used by children? Curr Probl Pediatr 1995; 25: 180–8.

36.

Spigelblatt

Laine-Ammara

Pless

Guyver

. The use of alternative medicine by children. Pediatrics 1994; 94: 811–4.

37.

Becker

Maiman

Kirscht

Haefner

Drachman

Taylor

. Patient perceptions and compliance: recent studies of the health belief model. Baltimore: Johns Hopkins University Press, 1979.

38.

Paterson

Thorne

Russell

. Disease-specific influences on meaning and significance in self-care decision-making in chronic illness. Can J Nurs Res 2002; 34: 61–74.

39.

Rapoff

. Management of adherence and chronic rheumatic disease in children and adolescents. Best Pract Res Clin Rheumatol 2006; 20: 301–14.

40.

Sabaté

. Adherence to long-term therapies: evidence for action. 2003. www.who.int/chp/knowledge/publications/adherence_full_report.pdf (accessed 2012 May 16).

41.

Sirithunyanont

Bhuripanyo

Kangkagate

Winyarat

Srichaya

Wangtip

. Accuracy of international normalized ratio determined by portable venous-blood coagulation monitor versus a central laboratory. J Med Assoc Thai 2003; 86 (suppl 1): S67–75.

42.

Taylor

Malfair SC

de Lemos

Jang

. Impact on patient satisfaction with a structured counselling approach on natural health products. J Oncol Pharm Pract 2008; 14: 37–43.