European Journal of Cardiovascular Medicine

Treatment of people living with HIV (PLHIV) with combination ART has improved survival remarkably with slow progress towards AIDS and improved quality of life. Immunological and virological markers help in modification in treatment regimen. [1] To evaluate the response to treatment, CD4 T-cell count and viral load are important parameters. The indicator for immune response is CD4 T-cell count and the indicator for virological response is viral load level. [2]

But a cluster of participants are unable to respond immunologically/ virologically in spite of treatment with cART. Immunological non-responders are termed as immunological discordance. [3] Virological non-responders are termed as virological discordance. Overall participants with immuno-virological discordance are at high risk of AIDS & AIDS-related infections/co-morbidities/cancers and finally death. [4] In the past, few studies mentioned the factors responsible for immuno-virological discordance. In this study the factors responsible for immunological discordance are low baseline CD4 cell count, poor HIV treatment adherence, not taking regular treatment for opportunistic infections (like pulmonary infection, candidiasis, diarrhea). [5] The factors responsible for virological discordance are poor adherence to therapy, presence of opportunistic infections & high baseline viral load >1000 copies/ml. Identifying these factors will have the impact on treatment outcome, regimen change and management of PLHIV with opportunistic infection. [6]

So, the present study is put forward to determine immuno-virological discordance amongst PLHIV and its effects on outcome of participants resulting in death (mortality).

Aim and Objectives:

Aim:  To determine the immuno-virological discordance amongst PLHIV on c ART and its effect on mortality & morbidity.

Objectives:

1. To assess the prevalence of Immuno-virological discordance among PLHIV.
2. To describe the factors responsible for non-AIDS related infections. 

This is a Cross-sectional study was conducted among Participants coming to ART center, Department of Microbiology, and sample processing is done at HIVTL laboratory at tertiary care center, Visakhapatnam.

Inclusion Criteria:

1. All participants diagnosed with HIV infection and taking cART for minimal period of one year.
2. Minimum 3 times tested for CD4 levels

Exclusion Criteria:

1. Participants who were < 1 year on cART.
2. Participants who were not tested for CD4 counts.
3. Lost to follow up and transfer out individuals were excluded from the study.

STUDY GROUP:

Subjects belonging to age group > 18 years of age, male and female, on cART treatment regimen at ART center, tertiary care center, Visakhapatnam.

DATA COLLECTION: 

Data is collected from PLHIV who are on cART for at least one year or more and visiting ART center. From all participants, written informed consent is taken. Socio-demographic characteristics i.e. age, sex, education, residence is taken. Base line and clinical data such as H/O opportunistic infections, H/O chronic non-communicable disease, and nutritional status HBV co-infection is taken. Baseline and CD4 count level taken from charts.CD4 count is done at the time of participants registration, followed by viral load testing after 6 months. Blood samples for CD4 count and viral load were collected during the data collection time.   

This is a Cross-sectional study was conducted among Participants coming to ART center, Department of Microbiology, and sample processing is done at HIVTL laboratory at tertiary care center, Visakhapatnam.

Inclusion Criteria:

1. All participants diagnosed with HIV infection and taking cART for minimal period of one year.
2. Minimum 3 times tested for CD4 levels

Exclusion Criteria:

1. Participants who were < 1 year on cART.
2. Participants who were not tested for CD4 counts.
3. Lost to follow up and transfer out individuals were excluded from the study.

STUDY GROUP:

Subjects belonging to age group > 18 years of age, male and female, on cART treatment regimen at ART center, tertiary care center, Visakhapatnam.

DATA COLLECTION: 

Data is collected from PLHIV who are on cART for at least one year or more and visiting ART center. From all participants, written informed consent is taken. Socio-demographic characteristics i.e. age, sex, education, residence is taken. Base line and clinical data such as H/O opportunistic infections, H/O chronic non-communicable disease, and nutritional status HBV co-infection is taken. Baseline and CD4 count level taken from charts.CD4 count is done at the time of participants registration, followed by viral load testing after 6 months. Blood samples for CD4 count and viral load were collected during the data collection time.   

1. Standard precautions are strictly followed and blood samples are collected for CD4count and viral load testing by using vacutainers. Each 3ml of whole blood is collected in a K2 EDTA evacuated tube using eclipse needle.
2. The tubes are stored at room temperature (15-30c) and sent to HIVTL lab in cold chain for CD4 count and viral load testing.
3. Second tube containing 3ml blood is centrifuged at 2000-2500rpm for 10-15minutes.
4. After centrifugation plasma is transferred in aliquot tube and sent to viral load lab.
5. Viral load testing done by Abbott m2000sp and m2000rt for DNA extraction and Real time HIV-1 assay, according to manufacturer’s instructions.
6. CD4 count testing done by Sysmex cyflow counter, according to   manufacturer’s instructions

Statistical Analysis:    

Data will be collected on excel sheet and will be analyzed using      suitable statistical tool. Data will be presented in proportion and percentages. Findings calculated in percentages and proportions will be presented in tables, charts and graphs.

Out of 774 participants registered at ART center, 570 are active on cART. Among them 52 participants (9.1) had immunological discordance. Forty-two (80.7%) patients had immunological discordance and 10(19.2%) had virological discordance.

All discordant participants are receiving combination ART region. 39(75%) out of 52 participants had good adherence to cART (>95%) and 13(25%) out of 52 had adherence to cART (<95%).

Mean baseline CD4 count (cell/mm3) among participants were ≤ 100in 93 participants, > 150 cell/mm3 in 112 participants ≥350 in 365participants

Mean viral load count copies among participates with >1000 in 50 participants < 1000 in 16 participants and remaining 504 showed TND

Table 1: Virological & Immunological responses among 570 participants in TCC at 12 months

Table:1   Out of 570 participants who came after 12 months and who had 12 months VL and CD4 count testing done, 142 had a CD4 site < 100 cell/mm3 out of these 32 has a detected viral load while 110 had full viral suspension i.e (immunological discordant response). Only five of those 32 had a viral load of 1000 copies/ml or above. Regarding virological discordance 140 of 570 patients has a viral load ≥ 1000 copies/ml at 12 months of whom 108 experience a CD4 count increase >100 cell/mm3.

Table: 2 Discordant population

Majority of discordant participants are between age group of 21 to 40 years , 23 (44.2%). 27(51.9%) were males. 24(46.1%) were females and 1(1.92%) were transgender. (Table-2).

Table 3: Distribution of Gender

Table 4: Distribution of Opportunistic infection

Among 52 discordant participants 6 (11.5%) were with pulmonary Tb. 1 (11.9%) with syphilis 2(3.8%) with chronic HBV co infection and 4(7.6%) were with chronic kidney disease.

Table 5: Distribution of Education

Education levels among discordance pop 9(17.3%) received primary level, 16(30.7%) received secondary level education 13(25%) completed college and 14(26.9%) were illiterate most participants resided in urban region i.e 30(57.6%) and 22(42.3%) participants resided in rural regions.

Table 6: Distribution of Adherence

Table 7: Distribution of Age at Initiation of ART

Late initiation of cART among discordant population above 35 years age group in 41 (78.8%) and below 35 years age group is 11(21.1%).

Table 8: Distribution of Viral load (copies/ml) at 12 months

Table 9: Distribution of Factors associated with Immunological discordant:

The common factors contributing to immunological poor discordant 42 is low base line CD4 levels (<100 cells) at initiation of cART (38%), adherence < 95% (28.5%). Of incidence opportunistic infection (35.7%), chronic infection (21.4%), co-infection HBV (11.9%).      

Table 10: Distribution of Factors associated with Virological discordant:

Factors associated with virological discordant. More common factors contributing to virological discordant (10) is poor adherence to cART (>95%) 50%, presence opportunistic infections 30% and high baseline viral load at initiation of cART 10%.

The establishment of immunovirological discordance is dependent on the criteria used to define immunological and virological failure. Other factors influencing its prevalence include the total duration of treatment, choice of the first-line treatment, and the stage of disease at which treatment was initiated. Initiation of treatment irrespective of CD4 count was recommended only after 2014, and thus in most previous studies assessing the incidence of discordance, a subset of patients receiving deferred treatment was invariably included. These factors are critical determinants of response to therapy and thus impact the results of any study. The current study included all patients receiving treatment immediately upon diagnosis. The overall prevalence of immunovirological discordance among patients in our study was 9.1%, comparable to studies in Northern Ethiopia (11.5%) and Brazil (9%), but lower than studies in Nigeria (33%). [8,9,10]

In our study, the prevalence of immunological nonresponse was 7.25%. In an Indian study of 2011, which used similar criteria for immunological failure, the incidence of immunological nonresponse was 13.59%. Incidence was lower in studies from Europe (12%, 15%), [10] South Africa (24%), and Nigeria (22.6%) and higher than a study in Ethiopia (2.7%). [11,12,13] The variation in prevalence can be explained by the different cutoffs used to define immunological failure.

Our study showed that the prevalence of virological nonresponse was 2.41%, which is lower than studies from Ethiopia (8.8%) and Nigeria (17%). The difference is due to different cut offs used to define virological failure. [14,15]

Our study demonstrated that both males (51.9%) and females (46%) were equally affected by immunovirological discordant responses. In studies in Rwanda, the male gender has been independently associated with a higher risk for immunological nonresponse. [16]

Low baseline CD4 was found in 38% of patients with immunological nonresponse which is similar to many other studies. [17] In a study among female sex workers in Africa, a discordant response was associated with a higher CD4+ T-cell count above 200 cells/μl at ART initiation. [18] Tuboi et al. [19] and Moore et al. [20] reported that increases in CD4 cell count after initiation of therapy might be greater in individuals with lower CD4+ T-cell count at therapy initiation. Some studies also found no correlation between baseline CD4 cell count and discordance. [21]

Association of lower baseline CD4 count with immunological nonresponse is possible due to many explanations such as impaired bone marrow hematopoietic function and decreased proliferative capacity, lower thymic output, dysfunction in some cytokine expressions, and CD4 cell destructions. [22]

The incidence of TB co-infection among immunological nonresponders was 16.6% which was in concurrence with studies in Korea. [23] A possible explanation would be that TB infection impairs cellular immunological responses through Mycobacterium tuberculosis-induced apoptosis of CD4+ cells which subsequently leads to the depletion of CD4+ cells and results in poor immunological recovery despite viral suppression. [24]

In our study, lesser than 95% adherence was associated with higher rates of both immunological and virological discordant responses. This was further evident from the fact that 25% of patients with immunological discordant responses did experience recovery from discordance at the end of 36 months of follow-up. Similar outcomes were observed from studies in Thailand. [25]

Among patients with virological nonresponse, TB was the most common opportunistic infection (11.5%). In a study in Ethiopia, TB co-infection was also associated with virological discordant responses. [26] In another study in Northern Ethiopia, age at or below 35 years at highly active ART initiation, male gender, type of regimen given, and good treatment adherence were associated risk factors for virological discordant response. [27]

Discordant responses are associated with an increased incidence of AIDS events such as Oncogene-induced senescence and cancers. Further, there is an associated risk of increased incidence of non-AIDS events such as stroke, liver failure, renal failure, endocarditis, meningitis, and all-cause death. [28] It is thus important to identify discordant responses, not only to reduce the incidence of complications as mentioned above but also to avoid unnecessary switches to second-line therapy.

During the study, the authors were able to assess the response to interventions such as stepped-up adherence and timely management of opportunistic infections, and as a result, 18.75% of total discordant and 25% of patients with immunological nonresponse experienced reversal, i.e., had an immunological recovery when observed for up to 36 months. There was no change in the status of patients who had virological nonresponse. This finding was a valuable input and could be a vital tool for improvement in response to cART, limiting the occurrence of discordance and reducing the risks associated with discordance.

The current study, to the best of the knowledge of the authors, is the first study from India, to study the prevalence of immunovirological discordant responses independently and analyze the factors independently associated with each response. The criteria used to define failure and establish discordance were adapted from NACO guidelines applicable to the period of the study.

The current study has a limitation that it included a lesser duration of follow-up as compared to previous similar studies. Further, this is only a single-center study, and more studies on the subject are required to be able to derive better conclusions.

Early initiation of cART regimen and timely management of opportunistic infection will reduce the immune-virological discordance and the life expectancy of people living with HIV. 

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