CHRISMED Journal of Health and Research

: 2016  |  Volume : 3  |  Issue : 2  |  Page : 106--111

Impact of medication adherence of oral hypoglycemic agents on clinical and economic outcomes: A report from resource-limited settings

Thamineni Rajavardhana, Kadapala Pruthvi Kumar Reddy, Golla Mallikarjuna, Dharmareddy Lakshmanamurthy, Maddirevula Maneesh Kumar Reddy, Easwaran Vigneshwaran 
 Department of Pharmacy Practice, Raghavendra Institute of Pharmaceutical Education and Research, Anantapuramu, Andhra Pradesh, India

Correspondence Address:
Thamineni Rajavardhana
Department of Pharmacy Practice, Balaji College of Pharmacy, Anantapuramu, Andhra Pradesh


Background: Achieving medication adherence is a major obstacle for the management of type II diabetes mellitus. Adherence to the prescribed regimen in terms of dose, frequency, and duration is particularly important to combat the existing clinical condition. The present study settings, being a drought area most of the patients are living under miserable conditions and nonadherence may leave the patients with a huge burden of health care cost. Aim and Objectives: To estimate the effect and to correlate the medication adherence on the clinical and economic outcome of patients with anti-diabetic therapy. Methodology: This study is a prospective cohort study carried out in a secondary care referral hospital. Seventy-six subjects were included and conducted with semi-structured interview for the collection of data. Apart from that, other sources such as medical records, labarotory records, and dispensing records were also used for data collection. The study subjects were divided into two groups' viz. good medication adherence and poor medication adherence groups based on their medication possession ratio (MPR). Results: MPR was found to have strong negative correlation to clinical variables such as gross random blood sugar levels. The mean total cost spent by poor medication adherence group subjects was more than ten folds higher than the good medication adherence group. Conclusion: The good medication adherence group was found to be associated with lesser health care cost and better clinical outcome. Hence, it can be considered as one of the possible ways to reduce economic burden and to manage type II diabetes mellitus patients in resource-limited settings.

How to cite this article:
Rajavardhana T, Reddy KP, Mallikarjuna G, Lakshmanamurthy D, Reddy MM, Vigneshwaran E. Impact of medication adherence of oral hypoglycemic agents on clinical and economic outcomes: A report from resource-limited settings.CHRISMED J Health Res 2016;3:106-111

How to cite this URL:
Rajavardhana T, Reddy KP, Mallikarjuna G, Lakshmanamurthy D, Reddy MM, Vigneshwaran E. Impact of medication adherence of oral hypoglycemic agents on clinical and economic outcomes: A report from resource-limited settings. CHRISMED J Health Res [serial online] 2016 [cited 2021 Jan 23 ];3:106-111
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Full Text


Diabetes mellitus is an endocrine disorder which refers to a group of common metabolic disorders, where the therapeutic and economic benefit of drug treatment is not realized in the day to day practice, especially for patients who are partially compliant to their therapy.[1],[2],[3] The worldwide prevalence of diabetes mellitus has risen dramatically over the past two decades, from an estimated 30 million cases in 1985–285 million in 2010.[4] Oral hypoglycemic agents are the major treatment options for type 2 diabetes mellitus, and poor medication adherence to these medications may lead to increased burden of diabetes mellitus.[3] It implies that good medication adherence is extremely important for better therapeutic outcomes, but evidence in resource-limited settings are scarce.[3],[5],[6],[7],[8] And at the same time, economic outcomes were also not measured in these local settings.

Achieving higher medication adherence rate is a major obstacle for the management of any type of disease and this is especially true in the case of chronic debilitating diseases such as diabetes.[9] Adherence to the prescribed regimen is particularly important to combat the existing clinical condition. Most of the times, medication-taking patterns are overlooked by the health care professionals leaving the patients with higher rates of disease progression and emergency visits.[10],[11],[12]

Plenty of factors are reported to influence medication adherence and it is clear that full benefit of the medications will be achieved only if patients stringently follow the prescribed treatment regimen.[8] However in our health care system, acute conditions are taken care of in a better way, and medication adherence rates are also higher in acute diseases than chronic diseases.[8],[13],[14]

The present study setting being a rural drought area, most of the patients are illiterate (literacy rate 26.73%),[15] economically backward, living in miserable conditions and may not be aware about the importance of regular medicine-taking behavior. This may leave the patients with huge financial burden and increased clinical complications as well.[16] Moreover, the studies pertaining to patient medication adherence are being carried out in developed countries and so the concept of medication adherence is well-understood by healthcare professionals and patients in developed countries.[17],[18] Whereas developing countries like India faces major setbacks due to the paucity of fund resources to conduct studies related to patient medication adherence.[17],[18],[19] Hence, the present investigation was undertaken to understand the effect of medication adherence on the clinical and economical outcome and to correlate the medication adherence on the clinical and economic outcome of patients with anti-diabetic therapy.


A prospective cohort study design was used to study the adherence of patients to oral anti-diabetic treatment regimens for July 2013 to April 2014 at a secondary care referral hospital belonging to nongovernmental charity organization located in resource-limited settings of Anantapuram district, Andhra Pradesh, India, where the patients obtain their own medicines at maximum retail price or subsidized rate based on caste and economic reservation. However, the study subjects included in the present study considered as nonreserved patients, receives their medicine at a maximum retail price.

The present study was approved by institutional review board. The purpose, objective and protocol of the present investigation were clearly explained to the study participants to obtain informed consent to participate in this investigation. A nonprobabilistic convenient sampling was done to recruit the study subjects based on their availability and willingness to participate in study. The type 2 diabetes mellitus patients aged 25 years and above, who are currently under the treatment with oral hypoglycemic agents at least for 2 months were included in the present study. There is no upper age limit for selection of subjects. The criteria for the subjects to recruit this study include fasting blood glucose levels of ≥130 mg/dl and postprandial blood glucose levels of ≥160 mg/dl. Individuals who were diagnosed with juvenile diabetes mellitus and gestational diabetes and who failed in Mini-Mental State Examination (MMSE) were excluded from the study.

The MMSE is a tool that can be used to systematically and thoroughly assess mental status. It is an 11-question measure that tests five areas of cognitive function: Orientation, registration, attention and calculation, recall, and language. The maximum score is 30 a score of 23 or lower is indicative of cognitive impairment.[20]

The data was collected through various sources such as patient medical records, laboratory records, dispensing records and through semi-structured interview of subjects. The data includes socio-demographic characteristics, income, frequency of drug intake, and reasons for nonadherence to pharmacotherapy. Medication possession ratio (MPR; days of medication collected as a proportion of days of medication prescribed over a particular period and the proportion of days covered within a given time period)[21],[22] was calculated for each patient and based on it the study subjects were divided into two groups' i.e. good medication adherence and poor medication adherence.

The patients with MPR of ≥0.8 were allotted to good medication adherence group and the remaining to poor medication adherence group. After making it into two groups, the subjects were followed subsequently for 8 months and the follow-up data was collected for every 2 months. The follow-up data includes clinical and economic outcome variables such as gross random blood sugar (GRBS) level, treatment cost, laboratory cost, total cost, and hospitalization details history for each patient.

Statistical analysis

The data were spread onto Microsoft Excel sheet and exported to Manufacturer :Graphpad InStat version 3.10 Registered to Marilyn L. Getchell, University of Kentucky for statistical analysis. The outcome variables are compared between two groups using Student's t-test (unpaired). Further the association between MPR to clinical and economic outcome variables were estimated using linear (Pearson) correlation analysis. The relative risk (RR) is also calculated between medication nonadherence and subsequent hospitalization. The probability value < 0.05 considered as significant.


We recruited 76 patients who met all study criterions. Among those identified for study inclusion, subjects with ≥60 years of age were more with a high frequency of male subjects. The study subjects were from a rural background, and most of them are illiterates. The monthly income of the present study population is in the income group of 3001–8000 Indian Rupees (INR) [Table 1].{Table 1}

The variables of interest include GRBS, medication cost, laboratory cost and total cost. Linear correlation analyses of MPR to clinical and economic outcomes are shown in [Table 2] where MPR taken as dependent variable.{Table 2}

The present study results show that MPR was found to have a strong association between all the variables of interest. It reveals that good medication adherence improves clinical condition and decreases economic burden which is evident from a negative correlation between MPR to GRBS and range of healthcare costs. We found that there was a significant difference between two analysis groups in terms of clinical and economic outcome of study subjects. The results also disclosed that the number of hospitalizations and the length of hospital stay was significantly reduced for subjects those who have better medication adherence. Other healthcare costs include medication cost, laboratory cost, and total cost were also significantly lesser in good medication adherence group, and they are detailed in [Table 3].{Table 3}

The GRBS score was found to have a significant difference between two groups, and the mean values are 154.37 ± 11.72 mg/dl and 186.93 ± 23.09 mg/dl for good and poor medication groups respectively. The health care cost burden to poor medication adherence is around 1385.93 INR, and it is more than ten-fold higher than good medication adherence group.

The RR and healthcare utilization cost of medication nonadherence are tabulated in [Table 4]. It was found to be high for in-patient admission (RR: 3.954) and it is 2.929 for casualty admissions. Huge financial burden was associated to in-patients (3005.50 INR), followed by outpatients due to medication nonadherence (1735.53 INR).{Table 4}


In this study, we investigated the impact of medication adherence to oral hypoglycemic on clinical and economic outcomes. For the majority of chronic diseases, poor medication adherence reduces the drug benefits and will have a negative impact on the clinical and economic outcome.[3],[16] Hence increased medication adherence may lead to a better clinical outcome, which will have an impact on the reduction of risk of complications, hospitalization, and reduced health care cost.[17] Further, lower income is more frequently associated with decreased medication adherence.[9] A study reported that a medication adherence will have a direct impact and association to a clinical outcomes such as HbA1C level and low-density lipoproteins cholesterol level in patients with diabetes.[23],[24]

Although evidence are available in the form of published literature stating that medication nonadherence may lead to negative consequences, there is little evidence available for their applicability in resource-limited settings.

The current study has provided empirical evidence that medication adherence in the form of MPR was found to have association with GRBS level and other costs include medical cost and laboratory cost. It also reveals that laboratory cost and medication cost were severely increased for poor medication adherence subjects. These results are coinciding with other research studies stating that medication adherence is associated with savings of total healthcare costs for diabetes, hypertension, and hypercholesterolemia.[23] For people with diabetes, total health care cost reduces simultaneously as adherence with oral hypoglycemic drugs increases. This is probably due to the effects of improved glycemic control which in turn reduces the need of medical services by preventing or reducing the severity of other related conditions (e.g., microvascular diseases, neuropathy, etc.).[25],[26],[27],[28]

The present study has very few numbers of therapy adherent subjects and this medication nonadherence may results in poor treatment outcome among those patients. These results are consistent with other retrospective and prospective studies, where they have provided an evidence that medication nonadherence subjects had a poor therapeutic outcome.[14],[29],[30]

Even though, relationship between hospitalization and medication nonadherence is not well-established for diabetic patients, still hospitalizations are the largest component of medical costs in many of the research studies. So changes in the hospitalization risks are a primary goal to cost savings can also be achieved through higher levels of adherence.[16],[31],[32] Lack of usage and over-usage of primary care clinics, comorbid conditions, and medication nonadherence is associated with great risk of subsequent hospitalization after treatment.[16],[33],[34]

The RR of hospitalization of the poor adherent group was high for different segments, which implies that increased adherence may reduce the economic burden indirectly in terms of decreased hospitalization. The decrease in hospitalization rate decreases the economic burden to the patients.[3],[16],[28]

Overall, the strong association between poor medication adherence to increased health care cost and negative clinical outcome stands similar to previously published evidence.[19],[30]

This study has few limitations that being an observational study and having smaller in sample size. In addition to that the present study site is charity hospital where the patients are provided with both subsidized and nonsubsidized rates (maximum retail price) for health care based on caste and economic reservation. However, this study included only the nonreserved patients that those who are receiving health care at a nonsubsidized rate, thus the results derived in this study is having a lacuna of generalized application.


Medication adherence may improve the patient's outcomes in both clinical and economic aspects. It also reduces the health care costs in the management of type II diabetes mellitus.

The good medication adherence group was found to be associated with lesser health care cost than poor medication adherence group. Poor medication adherence might increase the treatment costs and associated with poor clinical outcomes. Hence, medication adherence is an important aspect needs to be considered in the management of type II diabetes mellitus preferably in resource-limited setting.

Financial support and sponsorship


Conflicts of interest

There are no conflicts of interest.


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