Project – Medication Adherence and Treatment Outcomes among Patients with Chronic Diseases: A Study of Patients Attending University of Nigeria Teaching Hospital, Ituku-Ozalla

CHAPTER ONE

INTRODUCTION

1.1 Background to the Study

Chronic diseases have become a major public health concern globally because of their persistent nature, prolonged treatment requirements, and potential to produce severe complications when inadequately managed. Conditions such as hypertension, diabetes mellitus, cardiovascular diseases, chronic respiratory diseases, cancer, and other long-term illnesses frequently require patients to take prescribed medicines continuously over extended periods. The effectiveness of these medicines, however, depends not only on their pharmacological properties but also on whether patients take them correctly and consistently. The World Health Organization (WHO) described adherence to long-term therapy as a major determinant of treatment success and reported that poor adherence among patients with chronic diseases substantially reduces the benefits obtainable from available medicines. The WHO further noted that adherence problems are particularly significant in developing countries, where they interact with limited access to healthcare and medicines (World Health Organization [WHO], 2003). Thus, medication adherence represents an essential component of effective chronic disease management because the availability of effective medicines cannot translate into improved health outcomes when patients are unable or unwilling to use them as prescribed.

The burden of chronic diseases has continued to increase, placing considerable pressure on healthcare systems, particularly those in low- and middle-income countries. The WHO reported that noncommunicable diseases accounted for at least 43 million deaths globally in 2021, with cardiovascular diseases, cancers, chronic respiratory diseases, and diabetes constituting the major categories. A substantial proportion of premature deaths from these diseases occurs in low- and middle-income countries, where patients frequently experience challenges relating to diagnosis, continuity of care, affordability of medicines, and long-term disease management (WHO, 2025). In such settings, medication adherence becomes particularly important because chronic disease management often requires sustained pharmacological treatment in addition to lifestyle modification and regular clinical monitoring. Failure to adhere to prescribed medication may result in uncontrolled disease, disease progression, avoidable complications, repeated hospital visits, increased healthcare expenditure, and reduced quality of life. Consequently, improving medication adherence is increasingly regarded as an important strategy for improving treatment effectiveness and reducing the burden associated with chronic diseases.

Medication adherence is a multidimensional behaviour influenced by patient-related, medication-related, socioeconomic, healthcare-system, and disease-related factors. Patients may fail to take their medicines because of forgetfulness, perceived improvement in symptoms, adverse drug effects, complex medication schedules, high medication costs, inadequate knowledge of their illness, cultural beliefs, lack of social support, or difficulties accessing healthcare services. The WHO (2003) emphasised that non-adherence should not be viewed simply as a problem caused by patients because healthcare providers and healthcare systems also influence adherence behaviour. More recent evidence from sub-Saharan Africa has similarly shown that adherence is affected by socioeconomic barriers, therapy-related factors, health-system limitations, and sociocultural influences (Muyisa et al., 2026). These factors may interact, meaning that a patient can possess adequate knowledge of the prescribed regimen but still fail to adhere because medicines are unaffordable or unavailable. Therefore, understanding medication adherence requires consideration of the broader circumstances within which patients manage their chronic illnesses rather than focusing exclusively on individual behaviour.

The relationship between medication adherence and treatment outcomes is particularly important because adherence influences whether prescribed therapy achieves its intended clinical effect. For example, in hypertension, consistent use of prescribed antihypertensive medicines contributes to blood pressure control and reduces the risk of stroke, cardiovascular disease, kidney disease, and other complications. In Eastern Nigeria, Iloh, Ofoedu, Njoku, Amadi, and Godswill-Uko (2013) studied adults with primary hypertension attending a tertiary hospital and found medication adherence and blood pressure control rates of 42.9% and 35.0%, respectively. Their findings showed that blood pressure control was significantly associated with medication adherence, while forgetfulness was identified as a major reason for non-adherence. The findings demonstrate that adherence is not merely a behavioural issue but has direct implications for measurable clinical outcomes. Similar evidence from tertiary hospitals in Sokoto also demonstrated the importance of treatment adherence for blood pressure outcomes among hypertensive patients (Iloh et al., 2013).

Evidence from Nigeria also indicates that medication affordability and social support can influence both adherence and treatment outcomes among people living with chronic diseases. Adisa, Olajide, and Fakeye (2017), in a study involving hypertensive and type 2 diabetes patients in southwestern Nigeria, examined medication adherence, social support, medicine affordability, and disease-specific clinical outcomes. The study found that patients who were consistently able to afford their medicines demonstrated significantly better medication adherence and clinical outcomes. The study also showed that social and financial support remained important considerations in chronic disease management. Similarly, Oluwole et al. (2019), in a study of 500 hypertensive patients attending Lagos University Teaching Hospital, found that the majority of respondents demonstrated moderate adherence, while only a very small proportion had high adherence. Treatment satisfaction was significantly associated with medication adherence. These Nigerian findings indicate that adherence is influenced by practical and experiential factors surrounding patients’ treatment and that interventions aimed at improving treatment outcomes should address more than the prescription of medicines alone.

The problem of medication adherence is not limited to hypertension but extends to diabetes and other chronic conditions that require lifelong or prolonged medication use. A recent systematic review of medication adherence in diabetes management in sub-Saharan Africa found that adherence to antidiabetic medication remained suboptimal and varied considerably across settings. The review identified socioeconomic barriers, treatment-related factors, health-system limitations, and sociocultural influences as important contributors to non-adherence (Muyisa et al., 2026). Likewise, a large 2026 systematic review and meta-analysis involving more than 108,000 participants from 28 sub-Saharan African countries reported pooled adherence of approximately 67% for antidiabetic medicines and 51% for antihypertensive medicines. Education, self-efficacy, and social support emerged as important cross-cutting determinants of adherence. These findings suggest that even where medicines are prescribed and healthcare services are available, a substantial proportion of patients may not use their medications consistently enough to achieve optimal treatment control (Apostolou et al., 2026).

Within the Nigerian healthcare context, the need to investigate medication adherence and treatment outcomes at tertiary hospital level is particularly important because tertiary hospitals manage patients with complicated, multiple, and often long-standing chronic conditions. University of Nigeria Teaching Hospital (UNTH), Ituku-Ozalla, Enugu, serves as an important tertiary healthcare institution within southeastern Nigeria and provides specialised clinical services to patients referred from different levels of healthcare. Previous research conducted within UNTH has demonstrated the relevance of treatment adherence in chronic infectious disease management, including research involving patients attending the hospital’s chest clinic. The broader Nigerian literature, including studies conducted in tertiary hospitals in Eastern Nigeria, shows that adherence problems can be associated with poor disease control and adverse treatment outcomes. However, evidence specifically examining the relationship between medication adherence and treatment outcomes among patients with different chronic diseases attending UNTH, Ituku-Ozalla, remains important for generating institution-specific evidence. Investigating this relationship can provide healthcare professionals with information for designing patient-centred counselling, medication management, follow-up, and adherence-support interventions.

1.2 Statement of the Problem

Chronic diseases require sustained treatment, yet the effectiveness of prescribed medication is often undermined by inadequate medication adherence. Patients may receive appropriate diagnoses and prescriptions but fail to take medicines according to prescribed doses, schedules, or duration. The WHO (2003) identified poor adherence as one of the major reasons patients with chronic diseases fail to obtain the full benefits of their treatment and noted that adherence levels are often lower in developing countries. In Nigeria, the problem is reflected in studies of patients with hypertension and diabetes, where medication adherence has been associated with clinical control and treatment outcomes. The persistence of poor adherence means that some patients may continue to experience uncontrolled symptoms, disease progression, avoidable complications, and repeated healthcare utilisation despite the availability of effective medicines.

A major concern is that medication non-adherence is influenced by several interacting factors that may be difficult for healthcare providers to identify during routine clinical encounters. Forgetfulness, medication side effects, financial constraints, high pill burden, inadequate knowledge, dissatisfaction with treatment, and limited social support may all contribute to patients’ failure to follow prescribed medication regimens. Iloh et al. (2013), for instance, found that only 42.9% of patients in their Eastern Nigerian tertiary hospital study were adherent to medication, while only 35.0% achieved blood pressure control. Other Nigerian evidence has identified affordability and social support as important factors associated with adherence and clinical outcomes among patients with hypertension and diabetes (Adisa et al., 2017). These findings raise concerns about whether patients attending tertiary hospitals are receiving sufficient adherence counselling and support to overcome the barriers associated with long-term medication use.

Another problem concerns the possible consequences of poor medication adherence for treatment outcomes. In chronic disease management, treatment success is commonly reflected in measures such as controlled blood pressure, controlled blood glucose, reduced symptoms, prevention of complications, improved functional status, reduced hospitalisation, and improved quality of life. When medicines are not taken consistently, therapeutic effectiveness may be reduced, potentially resulting in persistent disease activity and complications. Evidence from Nigeria has demonstrated a relationship between treatment adherence and blood pressure outcomes, while broader African evidence shows that adherence remains suboptimal for both antihypertensive and antidiabetic medicines (Iloh et al., 2013; Apostolou et al., 2026). The implication is that failure to address medication adherence may limit the effectiveness of clinical treatment even where healthcare professionals prescribe appropriate medicines.

Despite the importance of medication adherence, there is a need for institution-specific evidence on how adherence relates to treatment outcomes among patients with chronic diseases attending UNTH, Ituku-Ozalla. Findings from other Nigerian locations cannot automatically be assumed to represent patients attending UNTH because patient characteristics, disease profiles, medication regimens, socioeconomic circumstances, healthcare experiences, and institutional practices may differ between settings. Although previous studies have examined adherence among specific chronic disease populations in Nigeria, there remains a need for evidence that considers patients with chronic diseases within the context of a major tertiary teaching hospital in southeastern Nigeria. Therefore, this study seeks to assess the level of medication adherence among patients with chronic diseases attending UNTH, identify factors associated with adherence, examine treatment outcomes, and determine whether a significant relationship exists between medication adherence and treatment outcomes. The findings are expected to provide evidence that can assist healthcare professionals in strengthening adherence counselling, patient education, follow-up practices, and other interventions aimed at improving chronic disease outcomes.

1.3 Purpose of the Study

The main purpose of this study is to examine medication adherence and treatment outcomes among patients with chronic diseases attending University of Nigeria Teaching Hospital, Ituku-Ozalla.

Specifically, the study seeks to:

1. determine the level of medication adherence among patients with chronic diseases attending University of Nigeria Teaching Hospital, Ituku-Ozalla;
2. identify the major factors influencing medication adherence among the patients;
3. examine the extent to which patients adhere to prescribed medication schedules and dosages;
4. assess the treatment outcomes experienced by patients with chronic diseases attending the hospital

1.4 Research Questions

The following research questions will guide the study:

1. What is the level of medication adherence among patients with chronic diseases attending University of Nigeria Teaching Hospital, Ituku-Ozalla?
2. What are the major factors influencing medication adherence among the patients?
3. To what extent do patients adhere to prescribed medication schedules and dosages?
4. What are the treatment outcomes experienced by patients with chronic diseases attending the hospital?

1.5 Research Hypothesis

The following null hypothesis will be tested at 0.05 level of significance:

H₀: There is no significant relationship between medication adherence and treatment outcomes among patients with chronic diseases attending University of Nigeria Teaching Hospital, Ituku-Ozalla.

1.6 Significance of the Study

The study will be significant to patients with chronic diseases because it will draw attention to the importance of taking prescribed medicines correctly and consistently. The findings may help patients understand how medication-taking behaviour can influence disease control, prevention of complications, quality of life, and overall treatment success.

The study will also be significant to doctors, nurses, pharmacists, and other healthcare professionals. The findings may provide evidence concerning the common barriers to medication adherence among patients attending the hospital. Such information may assist healthcare professionals in developing more effective medication counselling, patient education, follow-up, and adherence-monitoring strategies.

The study will benefit University of Nigeria Teaching Hospital, Ituku-Ozalla, by providing institution-specific evidence concerning medication adherence and treatment outcomes. Hospital administrators and clinical managers may use the findings to strengthen chronic disease management programmes and develop interventions directed at patients who experience difficulties with long-term medication use.

The study will be useful to pharmacists and pharmacy departments because medication-related factors such as dosage complexity, side effects, cost, and understanding of medication instructions may influence adherence. The findings may support greater involvement of pharmacists in medication counselling, medication review, adherence assessment, and patient follow-up.

The study will also be valuable to health policymakers and public health practitioners. Evidence concerning the relationship between medication adherence and treatment outcomes may contribute to policies and programmes designed to improve access to essential medicines, strengthen chronic disease services, and reduce preventable complications associated with poor disease control.

Furthermore, the study will contribute to academic knowledge and future research by providing evidence concerning medication adherence among patients with chronic diseases in a Nigerian tertiary healthcare setting. Researchers may use the findings as a basis for comparative studies, intervention studies, or investigations involving specific chronic conditions.

1.7 Scope of the Study

The study will focus on medication adherence and treatment outcomes among patients with chronic diseases attending University of Nigeria Teaching Hospital, Ituku-Ozalla, Enugu State.

The study will examine the level of medication adherence, adherence to prescribed dosage and medication schedules, factors influencing adherence, treatment outcomes, and the relationship between medication adherence and treatment outcomes.

The population of the study will comprise patients with chronic diseases receiving treatment at the hospital. Attention will be given to patients who have been diagnosed with chronic conditions requiring continuing medication management.

Geographically, the study will be restricted to University of Nigeria Teaching Hospital, Ituku-Ozalla, Enugu State. The study will not cover patients receiving treatment in other hospitals or healthcare facilities outside the selected study setting.

1.8 Operational Definition of Terms

Medication Adherence: The extent to which a patient takes prescribed medication according to the recommended dose, frequency, timing, and duration.

Medication Non-Adherence: Failure or inability of a patient to take prescribed medication according to the healthcare provider’s instructions.

Chronic Disease: A disease or health condition that generally persists for a long period and often requires continuing medical management, such as hypertension, diabetes, cardiovascular disease, chronic respiratory disease, and other long-term conditions.

Treatment Outcome: The health result or clinical condition achieved following treatment, which may include disease control, symptom improvement, prevention of complications, reduced hospitalisation, improved functional status, or other measurable indicators of treatment effectiveness.

Patients: Individuals diagnosed with chronic diseases who are receiving medical care and prescribed treatment at University of Nigeria Teaching Hospital, Ituku-Ozalla.

Medication Adherence Factors: Patient-related, medication-related, socioeconomic, healthcare-system, and disease-related circumstances that influence whether patients take their medicines as prescribed.

Tertiary Hospital: A specialised healthcare institution that provides advanced medical services, specialist consultations, diagnostic services, treatment, teaching, and referral care.

Treatment Compliance: The extent to which a patient follows healthcare instructions concerning medication, although the term medication adherence is preferred in this study because it recognises the active role of patients in treatment decisions and behaviour.

1.9 Organisation of the Study

The study will be organised into five chapters. Chapter One presents the introduction, comprising the background to the study, statement of the problem, purpose of the study, research questions, research hypothesis, significance of the study, scope of the study, operational definitions, and organisation of the study.

Chapter Two will present the review of related literature. It will examine relevant concepts, theoretical perspectives, empirical studies, and the literature gap relating to medication adherence and treatment outcomes among patients with chronic diseases.

Chapter Three will describe the research methodology. It will cover the research design, study area, population of the study, sample size determination, sampling technique, instrument for data collection, validity and reliability of the instrument, method of data collection, and method of data analysis.

Chapter Four will present the analysis and interpretation of data collected from the respondents. The research questions and hypothesis will be addressed using appropriate statistical procedures.

Chapter Five will provide the summary of findings, conclusion, recommendations, limitations of the study, and suggestions for further studies.

Project – Medication Adherence and Treatment Outcomes among Patients with Chronic Diseases: A Study of Patients Attending University of Nigeria Teaching Hospital, Ituku-Ozalla