Perceptions of Adherence The Use of Type 2 Anti-Diabetic Drug: Preliminary Study With Health Belief Theory Model

Diabetes Mellitus (DM) is a disease characterized by blood sugar levels above the standard value. One of the DM therapy’s managemen is pharmacological therapy. The use of medicines that comply with the instructions of use is one of the determinant factors for therapy success in type 2 DM patients. This study aims to explore the perceptions of DM patients regarding their medication adherence. This research is a qualitative approachby interviewing respondents. The perceptions of medication adherence were explored among the 20’s outpatient type 2 DM patients at Bali Royal Hospital, Denpasar, Bali. The six constructs of the Health Belief Model theory were applied. Data were analyzed with a content analysis approach. The results found that regarding Perceived Susceptibility and Perceived Severity constructs, the respondents believed they would be susceptible to hyperglycemia, and their disease will worsen if they are not devoted to using antidiabetic medicines. Perceived Benefit construct shows that respondents believed in medication adherence in maintaining their health. Respondents' Perceived Barrier revealed that their laziness and disregarded in taking their medications are the obstacles. Their strong will to get healthy represents the Cues of Action construct that would trigger their medication adherence. Finally, the self-Efficacy construct exposed respondents' confidence regarding medication adherence. Respondents' beliefs on Perceived Susceptibility, Severity, Benefit, Cues of Actions and Self-Efficacy help respondents to adhere using antidiabetic medicines. Perceived Barrier which respondents believe provides an obstacle to adhering using antidiabetic medicines.


INTRODUCTION
Diabetes Mellitus (DM) is a chronic disease which is a group of metabolic diseases with characteristic hyperglycemia that occurs due to abnormalities in insulin secretion, insulin action or both (1,2,3). The prevalence of DM in Indonesia based on the 2018 Basic Health Research (Riskesdas) in the population ≥ 15 years based on a doctor's diagnosis is 2%. This prevalence has increased compared to the 2013 Riskesdas results (4).
Type 2 diabetes affects many major organs, including the heart, blood vessels, nerves, eyes and kidneys. Managing diabetes and controlling blood sugar can lower the risk of complications. Diabetes increases the risk of serious health problems. Complications that occur in type 2 DM patients include: heart and blood vessel disease, nerve damage (neuropathy) in the limbs, other nerve damage, kidney disease, eye damage, skin conditions, slow healing and hearing loss (5)(6)(7)(8). DM complications in the form of microvascular and macrovascular causes people with DM who have complications to get many other types of drugs besides antidiabetic drugs (9).
The general management goal of DM therapy is to improve the quality of life for people with diabetes. Management goals include short-term goals, namely eliminating DM complaints, improving quality of life, and reducing the risk of acute complications. The long-term goal is to prevent and inhibit the progression of microangiopathy and macroangiopathy complications. The ultimate goal of management is to reduce DM morbidity and mortality (3). The management of DM begins with adopting a healthy lifestyle (medical nutrition therapy and physical activity) together with pharmacological interventions with oral and/or injection antihyperglycemic drugs. The number of types of drugs that must be used by people with DM affects the compliance of DM patients in using their drugs. In addition, the use of antidiabetic drugs in the long term (for life) can cause non-adherence to drug use among people with DM (9). Adherence in treatment can be interpreted as the behavior of patients who obey all the advice and instructions recommended by medical personnel. Compliant patients are seen as people who pay attention to their health (10). The level of adherence is an assessment of the patient that is used to find out whether a patient has followed the rules for drug use in undergoing therapy (11).
Knowledge of people with DM about antidiabetic drugs does not always increase adherence to using DM drugs. Many factors affect compliance with DM in using the drug, including age, gender, duration of DM diagnosis, family support, etc. (12,13). Adherence of medicines is related to controlled blood sugar levels in DM sufferers (14,15). Several methods have been introduced to measure medication adherence. Medication Adherence can be measured, among others, by the self-report method, calculating the Medication Possession Ratio (MPR), and the Morisky scale (16).
Much research has been carried out on adherence to drug use, including research conducted by Nanda et al in 2018 which stated that adherence to taking oral DM medication is related to controlling blood sugar levels in outpatient female patients aged 45-59 years at a community health center in Surabaya (17). Research conducted by Mita, et al in 2019 regarding adherence to the use of antidiabetic drugs at the Tabanan I Health Center revealed the results of 69 respondents that 52 respondents (75.36%) were categorized as adherent and the remaining 17 respondents (24.64%) were categorized as non-adherent (18). Research conducted by Srikartika, et al (2016) showed that factors such as patient characteristics and types of DM drugs affect adherence to using drugs (19). Yuwindri, et al (2016) revealed that the level of knowledge of type 2 DM patients significantly influences the patient's quality of life (31.6%) and adherence to drug use (25.1%). Drug ddherence use has a significant effect on the quality of life of patients (75.2%). Meanwhile, the increase in the effect of knowledge on the quality of life of patients was mediated by adherence to the use of DM drugs from 24% to 29% (20).
The Health Belief Model (HBM) has been used extensively to understand health behavior and provide guidance for designing health behavior improvement interventions. HMB theory has 6 constructs including Perceived Susceptibility (perceptions about vulnerability), Perceived Severity (perceptions about severity or seriousness), Perceived Benefit (perceptions about benefits), Perceived barriers (perceptions about obstacles), Cues of Action (triggers to act) and Self -efficacy (belief in one's own abilities). The constructs of Perceived Susceptibility and Perceived Severity are basically an assessment of the threat associated with the vulnerability of a disease and the potential severity or seriousness of the disease due to maintaining certain behaviors. Perceived Benefit implies an assessment of benefits that are useful for preventing the emergence of vulnerability or severity. Perceived Barrier can be interpreted that the perception of obstacles in changing behavior can hinder taking action to change. Cues of Action are triggers to take an action. Self-Efficacy is the confidence that he is able to perform certain actions (21).
Research using the theoretical framework of the Health Belief Model (HBM) has also been widely carried out. Nisa, et al (2017) examined the approach with the HBM theoretical framework for patient knowledge regarding DM-Disc dietary management. Health education based on HBM also plays an important role in increasing the knowledge of respondents because this method uses an approach that opens minds or makes respondents aware of DM disease and proper dietary management using DM-Disc (22). Research conducted by Rahma, et al (2017) regarding the description of Health Belief in patients with type 2 DM who seek treatment in the Pandanaran Health Center work area, Semarang shows that more than half of the respondents have a poor level of health belief (23). Fitriani, et al (2019) revealed that 5 constructs within the theoretical framework of HBM affect adherence of type 2 DM patients in using insulin among outpatients at a hospital in Surabaya (24).
Research on adherence of DM patients in using drugs is very important to study because DM is a silent killer. DM sufferers who use drugs not according to the rules result in increased blood sugar levels or hyperglycemia. Hyperglycemia has the risk of causing serious disturbances in the body's systems, especially blood vessels and nerves (1). Damage to these body systems will reduce the patient's quality of life and even result in death.
This study aims to explore the underlying factors or factors that underlie adherence of the use of antidiabetic drugs among people with DM who are on outpatient treatment using the theoretical framework of the Health Belief Model. The HBM theoretical framework has been used extensively to understand health behavior and provide guidance for designing health behavior improvement interventions (21). The HBM theoretical framework has 6 constructs namely Perceived Susceptibility (perceptions about vulnerability), Perceived Severity (perceptions about severity or seriousness), Perceived Benefit (perceptions about benefits), Perceived Barriers (perceptions about obstacles), Cues to Action (triggers to act) and Self-Efficacy (belief in one's own abilities) (21).

METHODS
This study uses a qualitative approach. The phenomenon that will be explained through this study is the perception of adherence to the use of antidiabetic drugs among people with DM who are undergoing outpatient care at RSU Bali Royal. An explanation of this phenomenon will be approached with the help of the HBM theoretical framework, which contains six constructs, namely: Perceived Susceptibility, Perceived Severity, Perceived Benefit, Perceived Barrier, Cues to Action, and Self-Efficacy.
The research was conducted at Bali Royal General Hospital which is located at Jl. Tantular No. 6 Denpasar, Bali. The time for data collection was from April to May 2021. Data was collected using interview techniques, which were carried out using an interview guide. The interview guide which is the instrument in this study was prepared based on the HBM theoretical framework. The population in this study were outpatient DM patients at Bali Royal General Hospital.
This study used a saturated sampling technique, that is, all patients who met the research criteria were included in this study. The number of research respondents was determined based on the achievement of data saturation or saturation, namely when no new information was found from the results of the interviews. Respondents' inclusion criteria included: patients with a diagnosis of DM who received anti-diabetic drugs, both OHO (Oral Hyperglycemia Drugs) and insulin, patients who checked themselves at the outpatient polyclinic from April to May 2021, patients with complicated and non-complicated DM, patients with diabetes mellitus comorbidities and without comorbidities. Exclusion criteria include: patients who are not willing to participate as research respondents. Interviews were conducted in the waiting room of the outpatient pharmacy, while the respondent was waiting for a prescription to be collected. The interview lasted about 30 minutes for one respondent.
Data analysis was transcribed verbatim and analyzed by content analysis. Content analysis was carried out referring to the research problem. This research has received Ethical Clearance from the UKDW Research Ethics Committee, with Number: 1301/C.16.FK/2021.

RESULTS AND DISCUSSION
This study involved 20 respondents who agreed to be interviewed, consisting of 13 male respondents and 7 female respondents. The estimated prevalence of diabetes in women aged 20-79 years is slightly lower than that of men (9.0% and 9.6%). In 2019, there were approximately 17.2 million more men than women living with diabetes. The prevalence of diabetes is expected to increase for both men and women in 2030 and 2045 (25). The average age of the respondents was 58.8 years from the range of 36-81 years. In 2019, it is estimated that the number of people with diabetes over the age of 65 is 111 million. One in five adults in this age group is estimated to have diabetes. It is projected that in 2030 the number of diabetics over 65 years will continue to increase to 195 million. In 2045 it will reach 276 million. These data demonstrate the substantial increase in the diabetes population in an aging society in the next 25 years, as well as the unavoidable public health and economic challenges this will bring (25).
Based on the data in Table 1, 85% of respondents have completed senior secondary education. Respondents' occupations were quite diverse, including employees, self-employed, teachers, retired employees, and housewives.  Table 2 summarizes the interview data regarding the profile of the antidiabetic drugs used by the respondents. Based on Table 2 above, the DM drugs used by respondents included oral drugs (OHO) and insulin injections. The most widely used oral drug is Metformin 500 mg. Metformin is the first choice in most cases of type 2 DM (3). The advantage obtained by using Metformin is that this drug increases insulin sensitivity in the liver and peripheral (muscle) tissue, thereby increasing glucose uptake. The increased insulin sensitivity in liver and muscle tissue reduced A1C levels by 1.5% to 2%, FPG (Fasting Plasma Glucose) levels by 60 to 80 mg/dL (3.3-4.4 mmol/L), and maintained ability to reduce FPG levels when very high, i.e. > 300 mg/dL or > 16.7 mmol/L. Metformin also reduces plasma triglyceride and low-density lipoprotein cholesterol (LDL) levels by 8% to 15% and slightly increases cholesterol high-density lipoprotein (HDL) (2%). Metformin does not cause hypoglycemia when used as monotherapy (9).  The perceptions of DM sufferers about adherence to using drugs explored in this study using the HBM theoretical construct are shown in Figure 1. The HBM theoretical framework is a behavioral model that explains individual reasons for choosing to behave in a healthy life or not (26).
Interviews with a questionnaire using the HBM framework were transcribed verbatim (27-30). The results of the study to explore the perceptions of adherence to drug use in people with DM at Bali Royal General Hospital using the Health Belief Model (HBM) theory obtained results that were explained using the 6 constructs contained in the HBM theory. The Perceived Susceptibility construct or perceptions of vulnerability generates the perception that respondents believe that if they are not compliant with DM drugs they will be prone to experiencing hyperglycemia, uncontrolled blood sugar, and affecting quality of life. This perception of vulnerability was expressed by respondents, explored through the question "What impact do you feel if you don't use DM drugs regularly?", stated by one of the following respondents: "My blood sugar level doesn't go down and my feet ache." Based on the question whether the perceived complaints affect the quality of life, the respondent's answer "Of course affects the quality of my life". Perceived vulnerability refers to a subjective assessment of the risk of developing a health problem (31). Based on the perception of susceptibility believed by the respondents, it can be concluded that the respondents understand the disease they are suffering from and understand the importance of using medication in an obedient and regular manner. This finding is in line with what was disclosed by Fitriani, et al (2019) that the more vulnerable patients feel, the more likely they are to adhere with taking their medication and following the advice of health workers (24). The Health Belief Model predicts that individuals who feel vulnerable to certain health problems will engage in behaviors to reduce the risk of developing health problems (26).
Perceived Severity or perceptions regarding severity reveal the perception that respondents believe that if they are not compliant using DM drugs it will affect the worsening of their DM disease. In the perception of vulnerability explored with the question "If you are not compliant in using DM drugs, will it affect the worsening/severity of the DM disease you are suffering from?". The answer given by the respondent was "Very influential, non-adherence with taking anti-diabetic medication makes DM disease worse". The severity of the disease in DM sufferers can be characterized by the emergence of microvascular and macrovascular complications, especially in the blood vessels, nerves, eyes, kidneys and the cardiovascular system. After 10-15 years from the time of diagnosis, the prevalence of all complications of Diabetes increases markedly (32). Perceived severity is based on a subjective assessment of the severity of the health problem and its potential consequences (33). This is in line with what was stated by Rahma and Hastuti (2017), namely if someone has the perception that DM is a serious disease, then that person has the intention to behave in controlling the disease (23).
Perceived Benefit is the perception of the benefits of adhering with DM medication. This construct reveals that respondents believe that if they adhere with DM medication, their blood sugar will be controlled, their body will be healthy, their energy will be fit, and they will be able to move. Perceptions of benefits were explored with the question "What do you think are the benefits that you can feel/get when using DM medication regularly and according to the instructions for use?" One respondent's answer was "By regularly using medication I become healthy, able to do activities and enjoy life". The respondent's perception explained that the respondent believed in the benefits of adherence to using antidiabetic drugs. Another answer from a respondent who works as a teacher regarding the perceived benefits of adhering to diabetes medication is "Feeling healthy, able to do activities and serve more". The benefits felt by individuals are based on the results of the individual's assessment of reducing the risk of a disease as a positive impact of a promotive action (33). If the patient feels the benefits after obediently using the medicine, then the patient will have confidence that his body is healthy. Thus the patient will act obediently using the drug as a form of prevention against uncontrolled blood sugar levels due to DM disease (24).
Perceived Barrier is the perception of obstacles in using DM drugs in an obedient manner. Researchers explored the factors that made respondents not comply with using DM drugs. The answers obtained were "Because of laziness and no enthusiasm for life", the answers of other respondents "Forgot to take medicine". The results of this study indicate that this construct uncovers obstacles that arise in terms of compliance with the use of DM drugs, namely because of forgetting the time to take the drug, feeling lazy, traveling long distances, forgetting to bring the medicine when eating out, having to adjust the hours of taking the drug with meal times, no zest for life, medicine rations are reduced. Within the framework of the HBM theory perceived barriers refer to individual judgments about barriers to behavior change (33). Based on this study, respondents did have obstacles in using drugs obediently. Research by Ulum, et al (2015) shows that the majority of respondents have a perception of mild obstacles to the act of complying with medical therapy (34).
Construct Cues to Action or triggers to act. Researchers explore triggers to act on respondents with the question "What do you think are the things that can make you use DM drugs obediently (regularly and according to instructions)?". The answer from one of the respondents "Want to be healthy, to be able to mingle with children and grandchildren and to keep working". In this study it was revealed that according to respondents the triggers in acting to comply with DM drugs were because they were able to comply, wanted to be healthy, used drugs practically, trusted doctors, wanted to improve patterns of drug use so that blood sugar levels were under control, and wanted to be free from disease. Based on exploring perceptions regarding Cues to Action, it shows that respondents try to behave obediently in using anti-diabetic drugs because they have expectations, things that are considered supportive, there is social influence, and experience. Cues to Action can arise from social influences, experiences, or fundamental changes. Experience and social influence influence confidence, attitudes, and motivation to change (35). The results of research by Rahma and Hastuti (2017) show that most respondents have the urge to take action related to self-care of their illness (23).
Self-Efficacy is a belief in one's ability to comply with DM medication. In this study, selfconfidence was explored with the question "Do you have confidence in being able to comply in using your DM medication?" regularly keeps my blood sugar level under control.", another answer is "Because I want to be healthy". Respondents in this study believed that they were able to comply in using DM drugs. Based on these answers the respondent has confidence in his abilities. Self-Efficacy is the confidence that he is able to perform certain actions (36). Keyakinan diri responden dapat dikaitkan dengan motivasinya untuk patuh menggunakan obatnya (13).

CONCLUSION
The Theory Health Belief Model used to reveal the perceptions of DM sufferers who seek outpatient treatment at the Bali Royal General Hospital in Denpasar City provides an overview of the factors underlying adherence to DM medication based on the Health Belief Model framework, both supporting and inhibiting factors. However, further research is needed to analyze which factors from the Health Belief Model contribute significantly to adherence to using antidiabetic drugs among DM sufferers.