Factors Associated with Antihypertensive Medication Adherence among Diabetic Patients with Coexisting Hypertension in a Tertiary Care Centre from a Low Middle Income South Asian Country

Document Type : Research Paper


1 Senior Registrar in Medicine Teaching Hospital, Jaffna, Sri Lanka.

2 University Medical Unit, University of Jaffna, Sri Lanka.

3 General Practitioner Civic Park Medical Centre, Sydney NSW 2145, Australia.


Poor medication adherence is a known preventable factor which can adversely affect   desired achievable blood pressure (BP) target. Strict control of blood pressure is essential among patients who have diabetes and hypertension (HT) in order to prevent complications. This is the first study conducted among 371diabetic patients with co-existing HT to examine the antihypertensive medication adherence in Sri Lanka to date.
Materials and Methods: 
This cross-sectional study was done in the general medical clinics of Jaffna Teaching Hospital from October 2019 to November 2019.
The majority (66.6%) of the patients were female. Mean age of the participants was 60.93 ± 9.77. The total mean score for modified MASES (Medication Adherence Self Efficacy Scale) was 48.1 ± 3.81. A negative correlation was noted between MASES scores and systolic (r= -0.033) and diastolic (r=- 0.083) blood pressure. Median score 49 was used to classify the patients into optimal or suboptimal adherence to antihypertensive medication. A significant percentage (43.4%CI: 38.4-48.5) of research participants were sub optimally adhered to antihypertensive medication. Among the associated factors explored, gender (P-0.007), low-income (P-0.002) and employed people (P-0.046) showed significant association with poor adherence. However, the number of co-morbidities (P-0.335), number of medications (P-0.454), duration of hypertension (P-0.440), and frequency of clinical visits (P-0.373) were not significantly associated with anti-hypertensive medication adherence.
This finding has an implication in clinical practice to improve the quality of care. Professionals should give consideration to above socio-demographic factors (gender, income, and occupation) before prescribing appropriate medication and its dosing schedule for hypertension.


  1. NCD Risk Factor Collaboration (NCD-RisC). Worldwide trends in blood pressure from 1975 to 2015: a pooled analysis of 1479 population-based measurement studies with 19.1 million participants. Lancet 2017, 389:37-55.
  2. Katulanda P, Ranasinghe P, Jayawardena R, et al. The prevalence, predictors and associations of hypertension in Sri Lanka: a cross-sectional population based national survey. Clin exp hypertens.2014; 36(7):484-91.

3.De Ferranti SD, de Boer IH, Fonseca V, et al. Type 1 diabetes mellitus and cardiovascular Disease: a scientific statement from the American Heart Association and American Diabetes Association. Circulation 2014; 130:1110–1130.

  1. Arauz-Pacheco C, Parrott MA, Raskin P; American Diabetes Association. Treatment of hypertension in adults with diabetes. Diabetes Care 2003; 26(Suppl. 1):S80–S82.
  2. Selvin E, Coresh J, GoldenSH, et al. Glycemic control, atherosclerosis, and risk factors for cardiovascular disease in individuals with diabetes: the atherosclerosis risk in communities study. Diabetes care.2005 Aug; 28(8):1965-73.
  3. Paromita King, Ian Peacock, Richard Donnelly. The UK Prospective Diabetes Study (UKPDS): clinical and therapeutic implications for type 2 diabetes.Br J Clin Pharmacol.1999 Nov; 48(5): 643–648.
  4. Dobbels F, Van Damme-Lombaert R, Vanhaecke J. Growing pains: non-adherence with the immunosuppressive regimen in adolescent transplant recipients. Pediatr Transplant 2005. Jun; 9(3):381-390
  5. Horne R. Compliance, adherence, and concordance: implications for asthma treatment. Chest 2006. Jul; 130(1)(Suppl):65S-72S 19.
  6. Agras WS. Understanding compliance with the medical regimen: the scope of the problem and a theoretical perspective. Arthritis Care Res 1989. Sep; 2(3):S2-S7.
  7. Noble LM. Doctor–patient communication and adherence to treatment. In: Myers LB, Midence K, eds. Adherence to treatment in medical conditions. Harwood Academic Publishers, 1998.p.51–82.
  8. Bandura A. Self-efficacy: toward a unifying theory of behavioural change. Psychological Review. 1977; 84(2):134–139.

12.Pirasath S, Kumanan T & Guruparan M , A Study on Knowledge, Awareness, and Medication Adherence in Patients with Hypertension from a Tertiary Care Centre from Northern Sri Lanka, International Journal of Hypertension, vol. 2017, Article ID 9656450, 6 pages, 2017. https://doi. org/10.1155/2017/9656450.

  1. Morisky DE, Ang A, Krousel-Wood MA, Ward H. Predictive validity of a medication adherence measure in an outpatient setting. J Clin Hypertens. 2008; 10:348–354.
  2. Ogedegbe G, Mancuso CA, Allegrante JP, Charlson ME. Development and evaluationof a medication adherence self ‑efficacy scale in hypertensive African-American patients. J Clin Epidemiol 2003; 56:520-9.
  3. Hacihasanoglu R, Gözüm S, Capik C. Validity of the Turkish version of the medication adherenceself‑efficacy scale‑short form in hypertensive patients; Anadolu Kardiyol Derg 2012;12:241-8. 16. Senaida Fernandez, William Chaplin, Antoinette Schoenthaler, Gbenga Ogedegbe Revision and Validation of the Medication Adherence Self-Efficacy Scale (MASES) in Hypertensive African Americans J Behav Med. 2008 Dec; 31(6): 453–462.
  4. World Health Organisation. (2003). Adherence to long-term therapies – Evidence for action. Retrieved from http:// apps. who. int/ medicinedocs/pdf/s4883e/s4883e.pdf
  5. Boratas S, Kilic HF. Evaluation of medication adherence in hypertensive patients and influential factors. Pak J Med Sci. 2018; 34(4):959-963. doi: https://doi.org/10.12669/pjms.344.14994
  6. Natarajan N, Putnam W, Van Aarsen K, Beverley Lawson K, Burge F (2013) Adherence to anti-hypertensive medications among family practice patients with diabetes mellitus and hypertension. Can Fam Physician 59: e93–e100.

20.Navya CJ, Naveen R, Ashwini GS, Manu A, Steve J, Singh J, et al. Adherence to medication among patients with hypertension and diabetes mellitus in selected tea estates in South India.JIMSA 2015;28(1):16–7.

  1. Okuboyejo, S. (2014). Non-adherence to medication in outpatient setting in Nigeria: The effect of employment status. Global Journal of Health Science, 6, 37–44. doi: 10.5539/ gjhs. v6n3p37
  2. Khanam MA, Lindeboom W, Koehlmoos TLP, Alam DS, Niessen L, Milton AH. (2014). Hypertension: Adherence to treatment in rural Bangladesh-findings from a population-based study. Global Health Action, 7, 1–9. doi: 10.3402/ gha. v7.25028 Anti-Hypertensive Medication Adherence among Diabetic Patients Ratnayake U, et al PSQI J, Vol. 9, No. 1, Win 2021 39
  3. Magadza C, Radloff SE, Srinivas SC. The effect of an educational intervention on patients’ knowledge about hypertension, beliefs about medicines, and adherence. Research in Social and Administrative Pharmacy, 5, 363–375. doi:10. 1016/ j. sapharm.2009.01.004
  4. Vawter L, Tong X, Gemilyan M, Yoon PW. Barriers to antihypertensive medication adherence among adults—United States, 2005. The Journal of Clinical Hypertension, 10, 922–929. doi:10.1111/j.1751-7176.2008.00049.x
  5. Herttua K, Tabák AG, Martikainen P, Vahtera J, Kivimaki M. (2013). Adherence to antihypertensive therapy prior to the first presentation of stroke in hypertensive adults: population-based study. European Heart Journal, 34, 2933–2939. doi:10.1093/eurheartj/eht219
  6. Bader RJK, Koprulu F, Hassan NAGM, Ali A. A A, Elnour AA. (2015). Predictors of adherence to antihypertensive medication in northern United Arab Emirates. Eastern Mediterranean Health Journal, 21, 309–318. Retrieved from http:// applications. emro.who. int/ emhj/ v21/ 05/ EMHJ_2015_21_5_309_318.pdf
  7. Uludag A, Sahin EM, Agaoglu H, Gungor S, Ertekin YH, Tekin M. Are blood pressure values compatible with medication adherence in hypertensive patients?. Niger J Clin Pract 2016; 19:460-4.
  8. Hayrettin, K., et al., The effect of the content of the knowledge on adherence to medication in hypertensive patients. AnadoluKardiyolojiDergisi, 2009. 09(03): p. 183-188.
  9. Persell SD, et al., Limited health literacy is a barrier to medication reconciliation in ambulatory care. Journal of general internal medicine, 2007. 22(11): p. 1523-1526.
  10. Williams MV, et al. Relationship of functional health literacy to patients' knowledge of their chronic disease - A study of patients with hypertension and diabetes. Archives of Internal Medicine, 1998. 158(2): p. 166-172.