Nkengla Menka Adidja^1,2,Valirie Ndip Agbor^3,4, Jeannine A. Atem^1,5, Calypse A. Ngwasiri^6,7, Josephine Mbuagbaw¹, Leopold N. Aminde⁸, Kathleen Ngu Blackett⁴

Authors’ affiliations

1. Faculty of Health Sciences, University of Buea, Buea, Cameroon
2. Djeleng Sub-divisional Hospital, Bafoussam, Cameroon
3. Ibal Sub-divisional Hospital, Oku, Cameroon
4. Faculty of Medicine & Biomedical Sciences, University of Yaounde 1, Yaounde, Cameroon
5. Mbingo Baptist General Hospital, Mbingo, Cameroon
6. Bamendjou District Hospital, Bamendjou, Cameroon
7. Clinical Research Education, Networking & Consultancy (CRENC), Douala, Cameroon
8. Faculty of Medicine, School of Public Health, The University of Queensland, Brisbane, Australia.

Corresponding Author: Dr. Nkengla Menka Adidja, Faculty of Health Sciences, University of Buea, Buea, Cameroon; Tel: +237 677173141, Email: This email address is being protected from spambots. You need JavaScript enabled to view it.

Abstract

Introduction: Hypertension is a challenging public health problem with huge burden in the developing countries. Non-adherenceto antihypertensive treatment is a big obstacle in blood pressure (BP) control and favours disease progression to complications. Our objectives were to determine the rate of non-adherence to antihypertensive pharmacotherapy, investigate factors associated with non-adherence and to assess the association between non-adherence and BP control in the Buea Health District (BHD), Cameroon.

Methods:  A community-based cross-sectional study using stratified cluster sampling was conducted in the BHD during January – March 2014.Eligible consenting adult participants had their BP measured using JNC-VII criteria. The Morisky medication adherence scale was used to assess adherence to BP lowering medication. Multivariable logistic regression models were used to predict non-adherence.

Results: One hundred and eighty-three participants were recruited with mean age of 55.9 years. Overall, 67.7% (95% CI = 59.8 – 73.6%) of participants were non-adherent to their medications. After adjusting for age, sex and other covariates; forgetfulness (aOR = 7.9, 95%CI: 3.0 – 20.8), multiple daily doses (aOR = 2.5, 95%CI: 1.2 – 5.6), financial constraints (aOR = 2.8, 95%CI: 1.1 – 6.9) and adverse drug effects (aOR = 7.6, 95%CI: 1.7 – 33.0) independently predicted non-adherence. BP was controlled in only 21.3% of participants and was better in those who were adherent to medication (47.5% versus 8.2%, p<0.01).

Conclusion: Non-adherence to antihypertensive treatment in the BHD was high. Multiple factors contribute to non-adherence including health care, medication, patient and disease-related factors. These should be targeted to improve adherence and BP control.

Key words: Hypertension, adherence, non-adherence, Morisky scale, Cameroon