|Year : 2015 | Volume
| Issue : 1 | Page : 57-60
Study of determinants of nonadherence to anti-hypertensive medications in essential hypertension at a Teaching Hospital in Southern India
RC Kumaraswamy1, Mohamed Murtuza Kauser1, M Kasi Jagadeesh2, R Uday Kumar2, SR Vagesh Kumar1, Asfia Afreen3, KM Sudha Madhavi4
1 Department of Medicine, Basaveshwara Medical College and Hospital, Chitradurga, Karnataka, India
2 Department of Pharmacy Practice, Basaveshwara Medical College and Hospital, Chitradurga, Karnataka, India
3 Department of Biochemistry, Basaveshwara Medical College and Hospital, Chitradurga, Karnataka, India
4 Department of Ophthalmology, Basaveshwara Medical College and Hospital, Chitradurga, Karnataka, India
|Date of Web Publication||14-Jan-2015|
Dr. R C Kumaraswamy
Department of Medicine, Basaveshwara Medical College and Research Centre, Chitradurga - 577 501, Karnataka
Source of Support: None, Conflict of Interest: None
Introduction: Hypertension is a chronic asymptomatic disease, often goes unnoticed for decades before it presents to the medical fraternity with devastating consequences. Low patient adherence is amenable for modification for better control of hypertension, if factors contributing to it are understood. Study was undertaken with the aims of assessing the factors responsible and their relative contributions toward nonadherence among hypertensives. Materials and Methods: We conducted a prospective observational study from August 2013 to August 2014. We included those, who attended the medicine outpatient department with a diagnosis of essential hypertension of more than 1 year duration. Results: A total of 516 patients were enrolled in the study, of which 132 (25.58%) were nonadherent. Marital status (P = 0.017), socioeconomic status (P = 0.000), level of education (P = 0.034), such as, illiteracy was associated with highest level of nonadherence compared with those with pre-matric and undergraduate education, whereas those with post graduate level of education showed absolute adherence to drugs and domiciliary status (P = 0.045) had statistically significant association with nonadherence. Other factors like younger age and male sex were associated with a higher degree of nonadherence, however statistical significance could not be obtained.
Keywords: Hypertension, nonadherence, socioeconomic status
|How to cite this article:|
Kumaraswamy R C, Kauser MM, Jagadeesh M K, Kumar R U, Vagesh Kumar S R, Afreen A, Sudha Madhavi K M. Study of determinants of nonadherence to anti-hypertensive medications in essential hypertension at a Teaching Hospital in Southern India. CHRISMED J Health Res 2015;2:57-60
|How to cite this URL:|
Kumaraswamy R C, Kauser MM, Jagadeesh M K, Kumar R U, Vagesh Kumar S R, Afreen A, Sudha Madhavi K M. Study of determinants of nonadherence to anti-hypertensive medications in essential hypertension at a Teaching Hospital in Southern India. CHRISMED J Health Res [serial online] 2015 [cited 2020 May 31];2:57-60. Available from: http://www.cjhr.org/text.asp?2015/2/1/57/149348
| Introduction|| |
Hypertension is a chronic asymptomatic disease, often goes unnoticed for decades before it presents to the medical fraternity with devastating consequences. Hence, constant screening of the population at risk and persistent adherence to prescribed medication reduces the risk of stroke, cardiovascular disease, renal disease and other complications.  Despite availability of effective antihypertensive medications, hypertension control is universally sub optimal often due to low patient adherence. ,
Low patient adherence is amenable for modification for better control of hypertension, if factors contributing to it are understood.  Determinants of medication on adherence are multi-factorial, and they range from accessibility, socio economic and educational status, complex drug regimens, demographic factors, and others (e.g. treatment side effects and co morbidities).  There is no clear consensus as to which patient groups are at higher risk nonadherence, how various factors influence low adherence, and how these factors can be modified to overcome the problem of nonadherence in different patient populations.
This study was undertaken with the aims of assessing the factors responsible and their relative contributions towards nonadherence among hypertensives.
| Materials and Methods|| |
We conducted a prospective observational study from August 2013 to August 2014, after obtaining the necessary clearance from the institutional Ethical Committee. We included those, who attended the medicine outpatient department with a diagnosis of essential hypertension of more than 1 year duration and excluded those with secondary hypertension and pregnancy.
Patients who fulfilled the inclusion criteria were subjected to a preset questionnaire after obtaining a written informed consent. The questionnaire included basic data, socio-economic factors, medication details, complications and reasons for nonadherence to medication.
The data thus obtained was tabulated and analysed using Statistical Package for Social Sciences 16 (SPSS version 16). One-way analysis of variance was used to assess the influence of different factors on nonadherence to medications.
| Results|| |
[Table 1] shows the socio-demographic profile of the study population and the influence of various factors on the adherence to antihypertensive medication. Higher proportion of the study populations were males (59.97%) compared with the females. Most of the patients were in the age group between 35 and 65 years (68.61%). Almost 85% of the study population were married individuals. The vast majority of patients (84.86%) belong to the lower, lower middle and upper lower classes of socioeconomic status (SES) in accordance with Kuppuswamy classification. 
|Table 1: Socio demographic profile and their impact on medication adherence|
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About 26% of the patients in this study had nonadherence to antihypertensive drugs. In our study males were found to be more nonadherent compared with the females and individuals in the younger age group (36-50 years) were also found to be more nonadherent. Married individuals were significantly more adherent to drugs than those who were single, divorced and widowed. Patients with lower SES were significantly nonadherent to medication compared to patients in the upper classes of Kuppuswamy classification. Education status among participants had a significant inverse relationship with a degree of nonadherence to medication. Furthermore, participants from urban areas were more adherent to drugs.
Other factors evaluated like duration since diagnosis, family history of hypertension, habits, co-morbidities, end-organ damage and knowledge of hypertension did not have a significant association with nonadherence to medication.
[Figure 1] shows the various reasons reported by the participants for being nonadherent. Nonadherence was contributed by varied factors such as side-effects, polypharmacy, nonaffordability, poor access to health care facilities, absence of significant change in health status, forgetfulness and patient's negligence.
| Discussion|| |
Drug adherence is an important issue in chronic and often asymptomatic disease like hypertension. The nonadherence to medication may result in devastating complications like acute coronary syndrome, cerebrovascular accidents, and renal failure to name a few.  Though some studies have been done in developed countries, there is scarcity of literature regarding drug adherence among hypertensives in Indian population. In a developing country like India, where majority of population lives in rural area with scarce resources and limited access to health care facility, often with low per capita income; diagnosis of chronic disease like hypertension can be financially devastating.
Some work has been done to assess barriers to medication adherence in selected populations. ,, In the present study, nonadherence rate was 25.58% which consistent with the other study reported by Lalic et al. in 2013.  Review of literature suggests that the nonadherence rate varies between 30% and 50% based on study methods used and the population under study. 
Several factors were evaluated for their effect on drug nonadherence; however their association was not always consistent.  In our study male, gender was associated with a higher likelihood of nonadherence (28.58% vs. 21.63%). Similar observations were reported in other studies such as by Ramli et al., Marentette et al., Caro et al. and Schoberberger et al. ,,, In our study it was observed that young hypertensives and those over 80 years were more likely to be nonadherent than middle aged individuals, reasons for such a finding could be due to lack of awareness, negligence and asymptomatic nature of the disease in young individuals, whereas in elderly it could be due to forgetfulness,  no care givers,  complexity  of regimen due to co-morbidities and inaccessibility to health care facilities because of age related issues. Similar observations were reported by several other researchers. ,
In chronic diseases, social environment has a significant role in long-term drug adherence as observed by Glasgow et al., which correlated with our observation that married individuals were significantly more adherent to hypertensives medications. This may be explained by the fact that the spouses usually will try to ensure the medications are taken on time. 
It is a well-known fact that financial status of an individual determines to a large extent, the affordability and accessibility to health care services. In our study, most of the patients from rural domicile who also had lower SES had significantly lower rate of adherence.  Similarly, nonadherence rates were also higher in those with poor educational status. 
As the reasons for nonadherence are multifactorial, multi-disciplinary approach is needed to tackle this problem. This can be done by better patient health care provider communication, educating the patient regarding the need for drug adherence and probably deleterious consequences of nonadherence and providing the drugs at subsidized rates. In the long run, adherence can be improved by improving the educational status of the patient, thereby their socio-economic conditions. This can ultimately lead to decreased hypertension-related complications and reduced health care cost to both the patient and to the government.
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