Journal of Clinical Research in HIV AIDS and Prevention
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  • Evaluation of Direct Cost of Adverse Drug Reactions to Highly Active Antiretroviral Therapy in Indian Human Immunodeficiency Virus Positive Patients

    Radhakrishnan Rajesh a       Sudha Vidyasagar b     Danturulu Muralidhar Varma b     Noorunnisa  c     Vasudeva Guddattu d    

    aManipal College of Pharmaceutical Sciences, Manipal University, Manipal – 576 104, Karnataka, India.

    bKasturba Medical College, Manipal University, Manipal – 576 104, Karnataka, India.

    cIndegene Lifesystems, Bangalore – 560 071, Karnataka, India.

    dDepartment of Statistics, Manipal University, Manipal – 576 104, Karnataka, India.


    In India, interruptions to highly active antiretroviral therapy (HAART) are due to adverse drug reactions (ADRs) and no reports on the direct cost incurred in the management of ADRs to HAART are available. There is a need to study direct cost incurred with ADRs to HAART to explore the high economic cost burden imposed by ADRs to HAART in HIV/AIDS patients. This study was aimed to evaluate the direct cost incurred in the management of ADRs to HAART in Indian HIV positive patients. This prospective study was conducted at a Medicine department in a South Indian tertiary care teaching hospitals were ADRs reporting system exist. HIV-positive hospitalized in-patients were identified and intensively monitored for ADRs to HAART. The World Health Organization (WHO) probability scale was used for causality assessment of ADRs. Modified Hart wig and Siegel scale was used for severity assessment of ADRs.Pearson chi-square test identified association of mean direct cost between ADRs and without ADRs by investigating total mean direct cost. The overall direct cost per ADRs to HAART was found to be higher in the context of expenditure on health care cost in India.

    Received 25 Jun 2012; Accepted 13 Oct 2012; Published 05 Dec 2012;

    Academic Editor:Christophe Marchand, Center for Cancer Research, National Cancer Institute, NIH, Bethesda, MD, 20892

    Checked for plagiarism: Yes

    Review by: Single-blind

    Copyright©  2012 Radhakrishnan Rajesh, et al.

    Creative Commons License    This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.

    Competing interests

    The authors have declared that no competing interests exist.


    Radhakrishnan Rajesh, Sudha Vidyasagar, Danturulu Muralidhar Varma, Noorunnisa , Vasudeva Guddattu (2012) Evaluation of Direct Cost of Adverse Drug Reactions to Highly Active Antiretroviral Therapy in Indian Human Immunodeficiency Virus Positive Patients . Journal of Clinical Research In HIV AIDS And Prevention - 1(1):12-21.
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    Human immunodeficiency virus (HIV) infected patients requires a combination of three to four antiretroviral, termed highly active antiretroviral therapy(HAART). HIV infected patients with HAART have a higher risk of developing adverse drug reactions (ADRs) than the general population and have a significant impact on patient’s current and future care options.1 ADRs to HAART is recognized as the key factor that increases the overall healthcare costs in both admission to hospital and prolongation of length of hospital stay.2 ADRs to HAART are one of the leading causes that affects the quality of life in HIV/Acquired immunodeficiency syndrome(AIDS) and results in increase in direct and indirect cost of HIV management with economic burden to the HIV infected patients as well as to the society.3 In India, the National AIDS Control organization (NACO) initiated free HAART for HIV and related opportunistic infections4.Currently, over 320,000 people living with HIV receiving HAART at more than 260 public government hospitals across the country. According to NACO treatment, HIV infected patients receive a fixed dose HAART regimen, consisting of either zidovudine or stavudine with lamivudine in combination with either efavirenz or nevirapine.5 In India, 25% of HIV patients discontinue their initial HAART regimen within the first eight months of therapy because of ADRs which leads to noncompliance.6 Studies7, 8, 9, 10have assessed the direct cost of ADRs at different hospitals using length of stay as a parameter for evaluation.. Recent study11 suggest that indirect cost such as disability, work productivity losses related to absenteeism and other financial cost was also associated in the management of HIV/AIDS. The evaluation of indirect cost associated from ADRs is rare and is found in only very few studies12.The cost analysis of ADRs in HIV infected patients depends upon different HAART regimen based on the patient’s viral load as well as individual level of HIV/AIDS care.13, 14, 15, 16 In an Australian study 5.7% of all admissions were drug related, out of which 4.9% were due to ADRs, resulted in a calculated cost of > € 2 million, or €3077 per patient.17Study Conducted in Germany estimated direct cost associated with ADRs ranged from 0.4 billion dollars annually.18In United States study19 revealed that the cost of ADRs per patient was in the range of US$2000 to US$4000. Wasserfallen et al 20 showed that a mean length of stay of nine days in a hospital attributes to ADRs resulting in a cost of €3122 per ADR. Moore et al 21showed that the average cost of ADRs was estimated to be €2900 and Lagnaoui et al22showed that the mean cost of ADRs € 2700 per patient in a department of internal medicine. In India, Ramesh et al23, 24estimated cost associated in treating all reported ADRs was US$ 1595, with average US$ 15 per ADR. Thiyagu et al2 study from India showed that total cost incurred due to ADRs in a tertiary care teaching hospital was found to be US$ 36451 with average US$ 115 per patient hospitalized with ADRs. The aim of this work was to evaluate the direct cost incurred in the management of ADRs to HAART in Indian HIV positive patients.

    Materials and Methods

    A prospective observational study was conducted from March 2010 to February 2011 among HIV-infected hospitalized in-patients by a clinical pharmacist at the medicine department in a teaching hospital where ADR reporting system exists. The study was approved by the institutional ethics committee. HIV-infected hospitalized in-patients of either sex who were on fixed dose drug combinations of HAART were included in the study and HIV positive patients with Systemic Lupus Erythmatosus (SLE), cancer, pregnant women and patients with traditional medicines were excluded from the study. Patients were divided into two groups. The first group with presence of ADRs to HAART regimen (Cases) and second group with absence of ADRs to HAART regimen (Controls). Based on the study criteria, the study procedure was explained and written informed consent was obtained from these patients. For the study purposes World health organization (WHO) definition of an ADR was adopted.25, 26

    During the study period, hospitalized in-patients was intensively monitored for short term and long term ADRs to HAART by active follow-up after treatment and ADRs was detected by asking patients directly and by screening patients medical case records. The occurrence of ADRs to HAART was documented with details of suspected HAART involved for ADRs; treatment given for ADRs was documented using ADR documentation forms. Documented ADRs was reviewed and assessed by senior clinical pharmacist and was reported to the treating clinicians and affected HIV patients. WHO probability scalewas used for the causality assessment of ADRs.27 The severity of suspected ADRs was assessed using the modified Hart wig and Siegel scale.28

    Evaluation of actual direct cost with ADRs and without ADRs to HAART was based on the cost of treatment, cost of hospitalization stay, and cost of laboratory investigations in comparison to a “normal” length of stay without ADR.29 In cases of ADR causing a hospital admission, all hospital costs to the ADR was calculated, as the patient would not have been hospitalized without the ADR i.e. length of stay multiplied by costs per in-patient per day. Assessment of ADR that leads to increase in the length of stay was performed after physician’s judgement. Billing details was collected from computerized Hospital In-Patients Billing System (HIPBS). The cost of treatment that includes, all costs of medications, surgical supply such as syringes, professional charges, nursing care charges, administrative charges. The cost of laboratory investigations that includes all costs of clinical laboratory investigation charges and any other invasive or noninvasive additional procedures performed. The cost of hospitalization charges includes cost of ward charges, bed charges and hospital stay charges. The data observed was analyzed in order to study the total mean direct cost versus mean direct cost per ADRs.

    Statistical Analysis

    Patients who presented with ADRs to HAART (Cases) and those who had not experienced with ADR to HAART (Controls) were compared with Chi-square test for gender, age and CD4 Count. Frequencies with percentage were used to represent gender, age, CD4 count, HAART regimen implicated, occurrence of ADRs and severity of ADRs to HAART. The association between direct cost incurred due to ADRs in HIV positive patients receiving HAART were determined at a P value <0.05 by investigating mean cost of treatment, mean cost of laboratory investigations and mean cost of hospitalization stay charges. (Minimum, maximum), Median and Chi-square test was used to evaluate the direct cost incurred to ADRs to HAART. All statistical calculations were performed using Statistical Package for Social Science (SPSS), version 17.0. A P-value of <0.05 was considered as statistically significant.


    A total of 110 HIV positive patients (84 males and 26 females) with HAART were admitted to the hospital during the study period. Out of which 56 patients (42 males and 14 females) experienced ADRs to HAART i.e. (Cases) and 54 patients was not experienced with ADRs to HAART i.e. (Control). A total of 57.2% of HIV positive hospitalized in-patients experienced ADRs to HAART and 41.1% of ADRs to HAART were related to hospital admissions. ADRs were highest with zidovudine + lamivudine+ nevirapine (35.5%) and lamivudine + stavudine + nevirapine (17.9%) combinations. CD4 cell count in patients with ADRs to HAART was ≤ 200 cells/ µl. Pearson chi-square test showed statistical significant difference of mean direct cost incurred among age group between cases and control (p=0.021 i.e. p<0.05). The total cost incurred in managing ADRs to HAART among age group 18-40 years INR 5391.2 (US$ 117.2) and 41-60 years INR 2714 (US$ 59). Demographic Characteristic of the patients is shown in Table 1.

    Table 1. Demographic Characteristic of the patients
    Patient Characteristics Number of Patients (%) Mean direct cost p-Value
      ADR present(Cases)(n= 56) ADR absent(Control)( n= 54) Number of patients(n=110) With ADR (Cases) Without ADR (Control)  
    Male 42(75) 42(77.8) 84 (76.4) 3818 83 1430.6 31.1 0.732
    Female 14(25) 12(22.2) 26 (23.6) 4719.6 102.6 1205.2 26.2
    Age (years)                
    18-40 29 (51.8) 20(37) 49(44.5) 5391.2 117.2 984.4 21.4 0.021
    41-60 23 (41) 34(63) 57(51.9) 2714 59 1614.6 35.1
    ≥ 60 4 (7.2)   4(3.6) 1904.4 41.4    
    CD4 Count (Cells/µl)                
    ≤ 200 44 (78.6) 43 (79.6) 87(79)     0.891
    >200 12 (21.4) 11(20.4) 23(21)    
    HAART regimen implicated            
    Zidovudine+Lamivudine+Nevirapine 20 (35.7) 15 (27.8) 35(31.8)    
    Lamivudine+Stavudine +Nevirapine 10 (17.9) 5(9.3) 15(13.6)    
    Tenofovir+Emtricitabine+Efavirenz 9 (16.1) 22 (40.7) 31 (28.2)    
    Zidovudine+Lamivudine+Efavirenz 7 (12.5) 6(11.1) 13(11.8)    
    Lamivudine+Stavudine+Efavirenz 6 (10.7) 5(9.3) 11(10.1)    
    Lamivudine+Stavudine+Tenofovir 1 (1.8)   1(0.9)    
    Tenofovir+Emtricitabine+Lopinavir+Ritonavir 3 (5.3) 1 (1.8) 4(3.6)    
    Occurrence of ADRs          
    ADRs during hospital stay 32 (57.2)        
    ADR is the reason for hospital admission 23(41.1)        
    Re occurrence of exposure of ADRs 1(1.7)        

    1US$ = 46 INR (Indian Rupees)
    p- Value of <0.05 was considered as statistically significant by pearson chi-square test.

    The direct cost incurred between cases (with ADR) and control (without ADR) was based on mean cost of treatment, mean cost of laboratory investigations and mean cost of hospitalization stay. It was identified that mean cost of treatment significantly contributed to the overall direct cost incurred between cases, INR 8556 (US$ 186) and control, INR 2645 (US$ 57.5). The mean cost of laboratory investigations with an ADR to HAART per patient was INR 1913.6(US$ 41.6). The mean cost of hospitalization stay with an ADR to HAART per patient was INR 3261.4(US$ 70.9).The median length of hospital stay with patients with ADRs to HAART was 10 days (range of 10 to 25 days) where as median length of hospital stay with HIV patients without ADRs to HAART was 4 days (range of 4 to 6 days). The association of direct cost incurred between cases (with ADR) and control (without ADR) in HIV positive patients receiving HAART was determined using Pearson chi-square test by investigating the mean cost of treatment (p=0.004 i.e. p<0.05), the mean cost of laboratory investigations (p=0.001 i.e. p<0.05) and mean cost of hospitalization stay (p=0.003 i.e. p<0.05). Results are summarized in Table 2.

    Table 2. Components of charges incurred in cases and control in intensively monitored HIV positive patients receiving highly active antiretroviral therapy.
      Mean direct cost Number of patients ( n =110) p-value  
    ADR present (Cases) (n= 56) ADR absent (Control) ( n= 54)
    INR US$ (Min,Max) Median( Q1, Q3) INR US$ (Min,Max) Median( Q1,Q3)
    Mean cost of treatment 8556 186 (138,53833) 1583.5(736,3329) 2645 57.5 (172,6081) 807(534,1758) 0.004
    Mean cost of laboratory investigations 1913.6 41.6 (535,6445) 1650 (1225,2250) 1168.4 25.4 (230,2835) 992(875,1326) p<0.001
    Mean cost of hospitalization stay 3261.4 70.9 (0,12150) 2590(1450,3743) 1927.4 41.9 (629,3780) 1672.5(1353,2322) 0.003

    ADR, adverse drug reaction
    Min= Minimum, Max= Maximum
    Median = (50th percentile)
    Q1 = Lower or first quartile (25th percentile)
    Q3= Upper or third quartile (75th percentile)
    1US$ = 46 INR (Indian Rupees)
    p- value of <0.05 was considered as statistically significant

    The total direct cost of treating ADRs to HAART was highest with tenofovir + emtricitabine + lopinavir + ritonavir combination, INR 21822.4 (US$ 474.4) and lamivudine + stavudine + tenofovir combination, INR 17521.4 (US$ 380.9). Mean direct cost incurred in treating per ADR in hospitalized patients with HAART ranges from INR 524.4 (US$ 11.4) to INR 17521.4 (US$ 380.9), as presented in Table 3.

    Table 3. Direct cost of adverse drug reaction (ADRs) involved in highly active antiretroviral therapy.
    Highly active antiretroviral therapy No of ADRs(n=56) Mean direct cost
    Mean cost of treatment Mean cost of Hospitalization stay Mean cost of lab investigations Total mean direct cost Mean cost per ADR
    Zidovudine+Lamivudine+Nevirapine 20 5276.2 114.7 3302.8 71.8 1932 42 10511 228.5 524.4 11.4
    Lamivudine +Stavudine +Nevirapine 10 1756.2 38.18 2750.8 59.8 1610 35 6117 132.98 607.2 13.2
    Tenofovir+Emtricitabine+Efavirenz 9 3997.4 86.9 3353.4 72.9 3353.4 72.9 10704.2 232.7 1186.8 25.8
    Zidovudine+Lamivudine+Efavirenz 7 2010.2 43.7 3183.2 69.2 1536.4 33.4 6729.8 146.3 961.4 20.9
    Lamivudine+Stavudine+Efavirenz 6 805 17.5 2323 50.5 1748 38 4876 106 809.6 17.6
    Lamivudine+Stavudine+Tenofovir 1 6762 147 6481.4 140.9 4278 93 17521.4 380.9 17521.4 380.9
    Tenofovir+Emtricitabine+Lopinavir +Ritonavir 3 13892 302 5400.4 117.4 2530 55 21822.4 474.4 7268 158

    1US$ = 46 INR (Indian Rupees)

    The cost of ADRs was studied based on the reported adverse reaction to HAART. In our study stavudine induced pancreatitis that led to highest cost of management INR 26105 (US$ 567.5) followed by efavirenz induced depression INR 19807.6 (US$ 430.6) followed by nevirapine induced Steven Johnson Syndrome (SJS) INR19182 (US$ 417), tenofovir induced renal failure INR 11113.6 (US$ 241.6) and zidovudine induced anemia INR 10695 (US$ 232.5). The ADRs that led to the lowest cost for management was reported with zidovudine induced fever INR 3362.6 (US$ 73.1) followed by stavudine induced peripheral neuropathy INR 4057.2 (US$ 88.2). The total direct costs of some of the important ADRs to HAART are summarized in Table 4.

    Table 4. Cost of some of the most important adverse drug reaction (ADRs) to highly active antiretroviral therapy.
    Adverse drug reactions  No of ADRsn=56(%) Mean direct cost of ADRs
    Mean cost of treatment to ADRs Mean cost of hospitalization stay due to ADRs Mean cost of lab investigations due to ADRs Total mean direct cost Mean direct cost per ADR
    Zidovudine induced anemia 15( 26.9) 5901.8 128.3 3008.40 65.4 1784.8 38.8 10695 232.5 713 15.5
    Zidovudine induced nausea & vomiting 7(12.5) 1743.4 37.9 2401.2 52.2 1858.4 40.4 6003 130.5 860.2 18.7
    Nevirapine and efavirenz induced hepatotoxicity 7(12.5) 1504.2 32.7 2387.4 51.9 1725 37.5 5616.6 122.1 802.7 17.45
    Stavudine induced peripheral neuropathy 6(10.8) 1030.4 22.4 1646.8 35.8 1380 30 4057.2 88.2 676.2 14.7
    Stavudine induced pancreatitis 4(7.1) 14536 316 7774 169 3795 82.5 26105 567.5 6527.4 141.9
    Efavirenz induced skin rash 3(5.7) 1886 41 2815.2 61.2 1610 35 6311.2 137.2 2106.8 45.8
    Nevirapine induced Stevens Johnson Syndrome (SJS) 2(3.5) 10672 232 6808 148 1702 37 19182 417 9591 208.5
    Tenofovir induced renal failure 2(3.5) 6072 132 2700.2 58.7 2341.4 50.9 11113.6 241.6 5556.8 120.8
    Efavirenz induced depression 2(3.5) 8004 174 7452 162 4351.6 94.6 19807.6 430.6 9903.8 215.3
    Zidovudine and Lamivudine induced pancytopenia 2(3.5) 2852 62 5612 122 1495 32.5 9959 216.5 4981.8 108.3
    Lopinavir and Ritonavir induced diarrhea 2(3.5) 2603.6 56.6 3657 79.5 1384.6 30.1 7645.2 166.2 3822.6 83.1
    Efavirenz induced gastritis 2(3.5) 1228.2 26.7 2456.4 53.4 1771 38.5 5455.6 118.6 2727.8 59.3
    Zidovudine induced fever 2(3.5) 294.4 6.4 2010.2 43.7 1058 23 3362.6 73.1 1683.6 36.6

    1US$ = 46 INR (Indian Rupees)

    In our study the direct cost incurred in managing ADRs to HAART reported was INR 72428(US$ 1574.51). The cost incurred in treating each ‘mild’, ‘moderate’ and ‘severe’ ADRs to HAART was INR 3549 (US$ 77.15), INR 39926 (US$ 867.95) and INR 28953 (US$ 629.41) respectively. The cost of management of ADRs to HAART based on the severity was summarized in Table 5. In our study, the overall incidence of ADRs to HAART was found to be 50.9%. In the majority of ADRs to HAART, causality assessment was ‘probable’ and ‘possible’ by WHO probability scale. Out of 56 ADRs to HAART, level of severity as per modified Hart wig and Siegel scale28 accounted for ‘mild 6(10.7%)’, ‘moderate 42(75%)’ and ‘severe 8(14.3%). Results are shown in Figure 1.

    Table 5. Cost based on severity of adverse drug reactions in intensively monitored HIV positive patients receiving highly active antiretroviral therapy.
    Severity Level No of ADRsn = 56(%) Cost of management of ADRs to HAART
    INR US$
    Mild Level 1 3(5.4) 3549 77.15
      Level 2 3(5.4)
    Moderate Level 3 1(1.7) 39926 867.95
      Level 4 (a) 18(32.2)
      Level 4 (b) 23(41)
    Severe Level 5 6(10.9) 28953 629.41
      Level 6 1(1.7)
      Level 7 1(1.7)
          72428 1574.51

    1US$ = 46 INR (Indian Rupees)

    Figure 1. Level of severity adverse drug reaction to highly active antiretroviral therapy
    Figure 1.


    This is the first study conducted on Indian HIV-infected patients that explores the direct cost incurred in the management of ADRs to HAART. Use of HAART results in a wide range of adverse effects which are expensive to manage leading to morbidity and mortality. In a United States study30, it has been shown that ADRs rank from the fourth to sixth leading cause of death. Various studies31, 32concluded that in industrialized countries, ADRs accounts for 5 to 10% of hospital costs. In the present study, we estimated only the direct cost incurred in the management of ADRs to HAART, as indirect cost includes social cost, loss of productivity that are difficult to analyze. Various studies 33, 34 have also analyzed direct cost of ADRs.

    Our study revealed male predominance over female. This may be due to the fact that in our study female HIV infected patients refuse for HIV treatment due to social stigma and illiteracy. These observations are in agreement with the previously published study elsewhere35. However, in our study mean direct cost incurred in treating ADRs to HAART in female patient was higher compared to males. This may be due to the fact that in our study two female HIV-infected patients presented with nevirapine induced Steven–Johnson Syndrome resulted in increased length of hospital stay of 20 days. This is in accordance with published studies.36, 37

    The total mean direct cost seems very less in developing country like India, compared to developed countries like United States where the direct cost incurred in treating ADRs to HAART ranges to several thousand dollars.19, 20 But when compared to economic status of expenditure on health care cost in India, this cost associated with ADRs is significantly high. This is because most of our HIV infected patients were below the poverty line, even unable to afford their daily food and inability to pay for their HAART. This is in accordance with published studies.38

    In our study, the patient presented with severe renal dysfunction with increased risk of grades 3 to 4 nephrotoxicity due to tenofovir usage, necessitating them to receive multiple dialysis. Thus overall costs leads to higher expenditure from the patients in terms of laboratory investigations to investigate tenofovir induced renal failure; the length of stay in the hospital was prolonged and resulted in escalating the cost of treatment. This finding is in agreement with published studies19, 20, 39where the laboratory investigations, length of hospital stay and treatment costs are responsible components for the overall direct cost of management of ADRs.

    In the management of stavudine induced pancreatitis costs incurred was due to laboratory investigations such as lipase measurement, serum amylase and imaging studies. Three patients in our study with stavudine induced pancreatitis also developed sepsis with systemic inflammatory response syndrome and multiple organ failure. The offending drug stavudine was withdrawn and patient was on supportive measures of intravenous fluid administration, complete bed rest in the hospital for 10 days. which leads to higher expenditure of direct cost. A finding consistent with the study carried out by Moore et al.40

    Efavirenz induced severe depression developed psychiatric symptoms with aggressive behavior with nonfatal suicide attempts, insomnia, irritability, suicidal ideation, impaired concentration, vivid dreams, and paranoid reactions and manic reactions. The patient’s length of stay in the hospital was prolonged for more than 20 days which resulted in higher cost burden associated with ADRs to HAART. These observations are in agreement with published study.41

    In our study the cost of management of nevirapine induced Steven–Johnson Syndrome (SJS) includes supportive measures with antimicrobial therapy, extra skin care, intravenous fluid administration, electrolyte maintenance cost and increased in the length of hospital stay in intensive medical care resulted in greater expenditure to the patient. One case of SJS with Level 7 severity which led to the death of the patient. This finding reflects the cost burden of ADRs to HAART. This is in accordance with published studies.42, 43, 44


    The overall direct cost associated in treating ADRs to HAART was found to be higher and significantly represents that ADRs to HAART increases the overall health care cost in the management of HIV/AIDS as well as reflects high economic burden to HIV/AIDS patients. I Clinicians and pharmacist must focus to prevent early ADRs to HAART thereby decreasing ADR related costs.


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