Association between adherence to antihypertensive medications and health outcomes in middle and older aged community dwelling adults; results from the Irish longitudinal study on ageing
To examine the association between antihypertensive medication (AHTM) implementation adherence and healthcare utilisation in community-dwelling adults aged ≥ 50 years in Ireland.
This was a prospective cohort study. The Irish Longitudinal Study on Ageing (TILDA) was linked to pharmacy claims data for participants aged ≥ 50 years. Participants were included if they had ≥ 3 pharmacy claims for one or more AHTM (ATC codes ‘C02’, ‘C03’, ‘C07’, ‘C08’ or ‘C09’) within the year preceding the year of self-reported healthcare utilisation outcome occurrence. Outcomes included self-reported general practitioner (GP), emergency department (ED), outpatient department visits and hospital admissions. Implementation adherence was measured using proportion of days covered (PDC), with participants classified as adherent if the average PDC ≥ 0.8. Negative binomial models were used to analyse the association between AHTM adherence and number of GP, ED, outpatient visits and hospitalisations (adjusted IRR and 95% CI are presented).
One thousand four hundred thirty-one participants were included. The majority of participants (72.6%) were considered adherent. Good implementation adherence to AHTM was associated with a significant decrease in self-reported GP visits (adjusted IRR 0.91, 95% CI 0.83–0.99). Adherence had no significant impact on the number of ED visits, outpatient visits or hospitalisations reported by TILDA participants.
Good adherence to AHTM was associated with less self-reported GP visits in this population, suggesting improved overall health status. However, the impact of medication non-adherence on the other self-reported healthcare utilisation outcomes (ED, outpatient visits and hospitalisations) was not evident in this study.
KeywordsMedication adherence Hospitalisation Health outcomes Older
The authors wish to thank TILDA staff at Trinity College Dublin and staff at the HSE-PCRS for collecting and providing the authors with the data used in this study.
Authors’ individual contributions
CW, CC and KB were involved in the concept and design of the study. Data was provided by TILDA and the HSE-PCRS. CW carried out the statistical analysis. All authors were involved in interpretation of the data. CW wrote the first draft of the manuscript and all authors contributed to subsequent drafts.
CW, CC and KB were funded by the Health Research Board (HRB), Research Leaders Award (HRB RL-2015-1579). This work was conducted as part of the SPHeRE Programme under Grant No. SPHeRE/2013/1. TILDA is supported by the Department of Health and Children, The Atlantic Philanthropies and Irish Life.
Compliance with ethical standards
Ethical approval for each wave of TILDA was obtained from the Trinity College Research Ethics Committee. Provision was made within this application to allow for the linking of participants GMS dispensing data, subject to participants’ consent.
The funding bodies had no role in this study design, data analysis, writing of the manuscript or the decision to submit for publication.
- 1.Vrijens B, De Geest S, Hughes DA, Przemyslaw K, Demonceau J, Ruppar T, Dobbels F, Fargher E, Morrison V, Lewek P, Matyjaszczyk M, Mshelia C, Clyne W, Aronson JK, Urquhart J, for the ABCPT (2012) A new taxonomy for describing and defining adherence to medications. Br J Clin Pharmacol 73(5):691–705. https://doi.org/10.1111/j.1365-2125.2012.04167.x CrossRefGoogle Scholar
- 10.Williamson JD, Supiano MA, Applegate WB, Berlowitz DR, Campbell RC, Chertow GM, Fine LJ, Haley WE, Hawfield AT, Ix JH, Kitzman DW, Kostis JB, Krousel-Wood MA, Launer LJ, Oparil S, Rodriguez CJ, Roumie CL, Shorr RI, Sink KM, Wadley VG, Whelton PK, Whittle J, Woolard NF, Wright JT Jr, Pajewski NM, for the SPRINT Research Group (2016) Intensive vs standard blood pressure control and cardiovascular disease outcomes in adults aged ≥75 years: a randomized clinical trial. JAMA 315(24):2673–2682. https://doi.org/10.1001/jama.2016.7050 CrossRefGoogle Scholar
- 11.Degli Esposti L, Saragoni S, Benemei S, Batacchi P, Geppetti P, Di Bari M, Marchionni N, Sturani A, Buda S, Degli Esposti E (2011) Adherence to antihypertensive medications and health outcomes among newly treated hypertensive patients. Clinicoecon Outcomes Res 3:47–54. https://doi.org/10.2147/ceor.s15619 CrossRefGoogle Scholar
- 12.Mazzaglia G, Ambrosioni E, Alacqua M, Filippi A, Sessa E, Immordino V, Borghi C, Brignoli O, Caputi AP, Cricelli C, Mantovani LG (2009) Adherence to antihypertensive medications and cardiovascular morbidity among newly diagnosed hypertensive patients. Circulation 120(16):1598–1605. https://doi.org/10.1161/circulationaha.108.830299 CrossRefGoogle Scholar
- 13.Yang Q, Chang A, Ritchey MD, Loustalot F (2017) Antihypertensive medication adherence and risk of cardiovascular disease among older adults: a population-based cohort study. J Am Heart Assoc 6(6). https://doi.org/10.1161/jaha.117.006056
- 19.Hope CJ, Wu J, Tu W, Young J, Murray MD (2004) Association of medication adherence, knowledge, and skills with emergency department visits by adults 50 years or older with congestive heart failure. Am J Health-Syst Pharm 61(19):2043–2049. https://doi.org/10.1093/ajhp/61.19.2043 CrossRefGoogle Scholar
- 22.Kenny RA, Whelan BJ, Cronin H, Kamiya Y, Kearney P, O’Regan C, Ziegel M (2010) The design of the Irish longitudinal study on ageing. Lenus the Irish Health Repository. https://www.lenus.ie/bitstream/handle/10147/301640/DesignReport2010.pdf;jsessionid=90014F67AA07262980411 E22BE26C4E3889?sequence=1. Accessed 10th October 2018
- 23.Barrett A, Burke H, Cronin H, Hickey A, Kamiya Y, Kenny RA, Layte R, Maty S, McGee H, Morgan K (2011) Fifty plus in Ireland 2011: first results from the Irish Longitudinal Study on Ageing (TILDA). Lenus the Irish Health Repository . https://www.lenus.ie/handle/10147/129741. Accessed 10th October 2018
- 28.Pittman DG, Tao Z, Chen W, Stettin GD (2010) Antihypertensive medication adherence and subsequent healthcare utilization and costs. Am J Manag Care 16(8):568–576Google Scholar
- 31.Kim S, Shin DW, Yun JM, Hwang Y, Park SK, Ko YJ, Cho B (2016) Medication adherence and the risk of cardiovascular mortality and hospitalization among patients with newly prescribed antihypertensive medications. Hypertension 67(3):506–512. https://doi.org/10.1161/hypertensionaha.115.06731 CrossRefGoogle Scholar
- 32.Haley WE, Gilbert ON, Riley RF, Newman JC, Roumie CL, Whittle J, Kronish IM, Tamariz L, Wiggers A, Morisky DE, Conroy MB, Kovalik E, Kressin NR, Muntner P, Goff DC (2016) The association between self-reported medication adherence scores and systolic blood pressure control: a SPRINT baseline data study. J Am Soc Hypertens 10(11):857–864.e852. https://doi.org/10.1016/j.jash.2016.08.009 CrossRefGoogle Scholar
- 33.Little P, Somerville J, Williamson I, Warner G, Moore M, Wiles R, George S, Smith A, Peveler R (2001) Psychosocial, lifestyle, and health status variables in predicting high attendance among adults. Br J Gen Pract 51(473):987–994Google Scholar
- 34.Dillon P, Smith SM, Gallagher P, Cousins G (2019) The association between pharmacy refill-adherence metrics and healthcare utilisation: a prospective cohort study of older hypertensive adults. Int J Pharm Pract. https://doi.org/10.1111/ijpp.12539
- 35.Prior S (2018) Budget 2019 papers: trends in general medical services (GMS). Department of Public Expenditure and Reform, Dublin. http://www.budget.gov.ie/Budgets/2019/Documents/Trends%20in%20General%20Medical%20Services%20(G454 MS)%20Scheme.pdf. Accessed on 20th December 2018
- 36.Butler RJ, Davis TK, Johnson WG, Gardner HH (2011) Effects of nonadherence with prescription drugs among older adults. Am J Manag Care 17(2):153–160Google Scholar
- 41.Grimes T, Fitzsimons M, Galvin M, Delaney T (2013) Relative accuracy and availability of an Irish National Database of dispensed medication as a source of medication history information: observational study and retrospective record analysis. J Clin Pharm Ther 38(3):219–224. https://doi.org/10.1111/jcpt.12036 CrossRefGoogle Scholar
- 42.Wallace E, Moriarty F, McGarrigle C, Smith SM, Kenny R-A, Fahey T (2018) Self-report versus electronic medical record recorded healthcare utilisation in older community-dwelling adults: comparison of two prospective cohort studies. PLoS One 13(10):e0206201. https://doi.org/10.1371/journal.pone.0206201 CrossRefGoogle Scholar