Drugs & Aging

, Volume 31, Issue 7, pp 527–540 | Cite as

Concurrent Use of Drugs and Supplements in a Community-Dwelling Population Aged 50 Years or More: Potential Benefits and Risks

  • Jure Peklar
  • Martin Charles Henman
  • Mitja Kos
  • Kathryn Richardson
  • Rose Anne Kenny
Original Research Article



The use of vitamin and mineral (VMs) and non-vitamin/non-mineral supplements (non-VMs) in the general population and the older population in developed countries has increased. When combined with drugs, their use can be associated with benefit and potential risks.


The aims of this study were to determine the extent and associated factors of the combined use of drugs and VM/non-VM supplements, and to examine the potential major drug–supplement interactions


Cross-sectional analysis of first-wave data of TILDA, The Irish Longitudinal Study on Ageing, nationally representative a cohort including 8,081 community-dwelling persons aged ≥50 years. Prevalences including 95 % confidence intervals (CI) were weighted to the population. Group differences in drug and supplement use were assessed using Pearson’s Chi-square test, and associations between concurrent drug–supplement use and covariates were assessed using logistic regression. Potential interactions between drugs and supplements were assessed using relevant sources.


Every seventh respondent (14.0 %; 95 % CI 13.1–15.0) reported regular concurrent use of drugs and supplements; 7.9 % (95 % CI 7.3–8.6) took only VMs, 3.9 % (95 % CI 3.4–4.4) took only non-VMs, and 2.2 % (95 % CI 1.8–2.6) took at least one of each concurrently with drugs. Concurrent use was more prevalent in women and in the oldest (≥75 years) group. Chronic disease, female sex, third-level education and private medical insurance were associated with an increased likelihood of use of both supplement types, whereas those classed as employed were much less likely to use any supplements. Supplements were combined with drugs in all of the commonly prescribed therapeutic groups, ranging from just under 60 % with drugs for bone diseases to 15.7 % with drugs for diabetes. Potential major drug–supplement interactions were detected in 4.5 % (95 % CI 3.4–5.8) of concurrent drug–supplement users, and were more prevalent in older respondents.


Concurrent use of drugs and supplements among those aged over 50 years in the Irish population is substantial and increases with age. There is considerable variation in usage, and the outcome of this approach is evidence of unmet need and therefore unrealised benefits among some subgroups, and of exposure to avoidable and potential serious drug interactions among others.


Rosuvastatin Food Supplement Adverse Drug Reaction Reporting Supplement Type Thyroid Hormone Replacement Therapy 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.



The authors wish to thank the Irish Medicines Board for the pharmacovigilance data on food supplement use and to acknowledge the contribution of the TILDA participants and research staff.

This work was supported by Irish Life; the Department for Health and Children; and by The Atlantic Philanthropies. The sponsors had no role in the design and conduct of the study; collection, management, analysis and interpretation of the data; or preparation, review and approval of the manuscript.

The authors have no potential conflicts of interest that are directly relevant to the content of this study.

The presented work has not been submitted elsewhere. Preliminary results were presented at a poster session at the British Geriatric Society Spring meeting in Belfast, April 2013.

J. Peklar and K. Richardson had full access to all of the data in the study and take responsibility for the integrity of the data and the accuracy of the data analysis.

Study concept and design: All authors.

Analysis and interpretation of data: J. Peklar, M.C. Henman, M. Kos.

Drafting of the manuscript: J. Peklar and M.C. Henman.

Statistical analysis: J. Peklar, K. Richardson.

Study supervision: M.C. Henman, M. Kos, R.A. Kenny.


  1. 1.
    Skeie G, Braaten T, Hjartåker A, et al. Use of dietary supplements in the European Prospective Investigation into Cancer and Nutrition calibration study. Eur J Clin Nutr. 2009;63(Suppl 4):S226–38.PubMedCrossRefGoogle Scholar
  2. 2.
    Kelly JP, Kaufman DW, Kelley K, et al. Recent trends in use of herbal and other natural products. Arch Intern Med. 2005;165(3):281–6.PubMedCrossRefGoogle Scholar
  3. 3.
    Qato DM, Alexander GC, Conti RM, et al. Use of prescription and over-the-counter medications and dietary supplements among older adults in the United States. JAMA. 2008;300:2867–78.PubMedCentralPubMedCrossRefGoogle Scholar
  4. 4.
    Denison HJ, Jameson KA, Syddall HE, et al. Patterns of dietary supplement use among older men and women in the UK; findings from the Hertfordshire Cohort Study. J Nutr Health Aging. 2012;16(4):307–11.PubMedCrossRefGoogle Scholar
  5. 5.
    Peng CC, Glassman PA, Trilli LE, et al. Incidence and severity of potential drug–dietary supplement interactions in primary care patients: an exploratory study of 2 outpatient practices. Arch Intern Med. 2004;164(6):630–6.PubMedCrossRefGoogle Scholar
  6. 6.
    Nahin RL, Pecha M, Welmerink DB, et al. Concomitant use of prescription drugs and dietary supplements in ambulatory elderly people. J Am Geriatr Soc. 2009;57(7):1197–205.PubMedCrossRefGoogle Scholar
  7. 7.
    Peklar J, Henman MC, Richardson K, et al. Food supplement use in community dwelling population aged 50 and over in the Republic of Ireland. Complement Ther Med. 2013;21(4):333–41.PubMedCrossRefGoogle Scholar
  8. 8.
    Izzo AA, Ernst E. Interactions between herbal medicines and prescribed drugs. Drugs. 2009;69(13):1777–98.PubMedCrossRefGoogle Scholar
  9. 9.
    Tsai HH, Lin HW, Pickard AS, et al. Evaluation of documented drug interactions and contraindications associated with herbs and dietary supplements: a systematic literature review. Int J Clin Pract. 2012;66:1056–78.PubMedCrossRefGoogle Scholar
  10. 10.
    Kearney PM, Cronin H, O’Regan C, et al. Cohort profile: the Irish Longitudinal Study on Ageing. Int J Epidemiol. 2011;40(4):877–84.PubMedCrossRefGoogle Scholar
  11. 11.
    Directive 2002/46/EC of the European Parliament and of the Council of 10 June 2002 on the approximation of the laws of the Member States relating to food. Official Journal L 183, 12/07/2002 P.0051–0057. Accessed 26 Jan 2013.
  12. 12.
  13. 13.
    Lexi-Comp OnlineTM, Lexi-InteractTM. Hudson: Lexi-Comp, Inc.; 2011. Accessed 19 Feb 2013.
  14. 14.
    Baxter K, editor. Stockley’s drug interactions [online]. London: Pharmaceutical Press. Accessed 19 Feb 2013.
  15. 15.
    Gardiner P, Graham RE, Legedza ATR, et al. Factors associated with dietary supplement use among prescription medication users. Arch Intern Med. 2006;166:1968–74.PubMedCrossRefGoogle Scholar
  16. 16.
    Morgan TK, Williamson M, Pirotta M, et al. A national census of medicines use: a 24-hour snapshot of Australians aged 50 years and older. Med J Aust. 2012;196(1):50–3.PubMedCrossRefGoogle Scholar
  17. 17.
    Barrett A, Savva G, Timonen V, et al. Fifty plus in Ireland 2011. First results from the Irish Longitudinal Study on Ageing, 2011 TILDA: Dublin; 2011.Google Scholar
  18. 18.
    Harrison RA, Holt D, Pattison DJ, et al. Are those in need taking dietary supplements? A survey of 21 923 adults. Br J Nutr. 2004;91(4):617–23.PubMedCrossRefGoogle Scholar
  19. 19.
    Touvier M, Niravong M, Volatier JL, et al. Dietary patterns associated with vitamin/mineral supplement use and smoking among women of the E3N-EPIC cohort. Eur J Clin Nutr. 2009;63(1):39–47.PubMedCrossRefGoogle Scholar
  20. 20.
    Irish Government, Department of Health. Healthy Ireland—a framework for improved health and wellbeing 2013–2025. 2013. Accessed 27 Nov 2013.
  21. 21.
    National Institute for Health and Clinical Excellence. Alendronate, etidronate, risedronate, raloxifene, strontium ranelate and teriparatide for the secondary prevention of osteoporotic fragility fractures in postmenopausal women. Accessed 7 Nov 2012.
  22. 22.
    Irish Universities Nutrition Alliance. National Adult Nutrition Survey. Accessed 27 Nov 2013.
  23. 23.
    Central Statistics Office. Statistical yearbook of Ireland 2011 edition. Accessed 26 Sep 2012.
  24. 24.
    Central Statistics Office. Population and labour force projection 2011—2041. 2012. Accessed 27 Nov 2013.
  25. 25.
    Jacobsson I, Jönsson AK, Gerdén B, et al. Spontaneously reported adverse reactions in association with complementary and alternative medicine substances in Sweden. Pharmacoepidemiol Drug Saf. 2009;18:1039–47.PubMedCrossRefGoogle Scholar
  26. 26.
    Patel DN, Low WL, Tan LL, et al. Adverse events associated with the use of complementary medicine and health supplements: an analysis of reports in the Singapore Pharmacovigilance database from 1998 to 2009. Clin Toxicol. 2012;50(6):481–9.CrossRefGoogle Scholar
  27. 27.
    Vohra S, Cvijovic K, Boon H, et al. Study of Natural Health Product Adverse Reactions (SONAR): active surveillance of adverse events following concurrent natural health product and prescription drug use in community pharmacies. PLoS One. 2012;7(9):e45196.PubMedCentralPubMedCrossRefGoogle Scholar
  28. 28.
    Richardson K, Kenny RA, Peklar J, et al. Agreement between patient interview data on prescription medication use and pharmacy records in those aged older than 50 years varied by therapeutic group and reporting of indicated health conditions. J Clin Epidemiol. 2013;66(11):1308–16.Google Scholar
  29. 29.
    Qato DM, Schumm LP, Johnson M, et al. Medication data collection and coding in a home-based survey of older adults. J Gerontol B Psychol Sci Soc Sci. 2009;64B(S1):i86–93.PubMedCentralCrossRefGoogle Scholar

Copyright information

© Springer International Publishing Switzerland 2014

Authors and Affiliations

  • Jure Peklar
    • 1
    • 2
  • Martin Charles Henman
    • 2
  • Mitja Kos
    • 1
  • Kathryn Richardson
    • 3
  • Rose Anne Kenny
    • 3
    • 4
    • 5
  1. 1.Faculty of PharmacyUniversity of LjubljanaLjubljanaSlovenia
  2. 2.School of Pharmacy and Pharmaceutical SciencesTrinity College DublinDublinIreland
  3. 3.The Irish Longitudinal Study on Ageing (TILDA)Trinity College DublinDublinIreland
  4. 4.Department of Medical GerontologyTrinity College DublinDublinIreland
  5. 5.Trinity College Institute of NeuroscienceSt James’s HospitalDublinIreland

Personalised recommendations