Rates and determinants of virologic and immunological response to HAART resumption after treatment interruption in HIV-1 clinical practice

The Effect of HIV Treatment Interruption on Subsequent Immunological Response

Recovery of CD4-positive T lymphocyte count after initiation of antiretroviral therapy (ART) has been thoroughly examined among people with human immunodeficiency virus infection. However, immunological response after restart of ART following care interruption is less well studied. We compared CD4 cell-count trends before disengagement from care and after ART reinitiation. Data were obtained from the East Africa International Epidemiology Databases to Evaluate AIDS (IeDEA) Collaboration (2001-2011; n = 62,534). CD4 cell-count trends before disengagement, during disengagement, and after ART reinitiation were simultaneously estimated through a linear mixed model with 2 subject-specific knots placed at the times of disengagement and treatment reinitiation. We also estimated CD4 trends conditional on the baseline CD4 value. A total of 10,961 patients returned to care after disengagement from care, with the median gap in care being 2.7 (interquartile range, 2.1-5.4) months. Our model showed that CD4 cell-count increases after ART reinitiation were much slower than those before disengagement. Assuming that disengagement from care occurred 12 months after ART initiation and a 3-month treatment gap, CD4 counts measured at 3 years since ART initiation would be lower by 36.5 cells/μL than those obtained under no disengagement. Given that poorer CD4 restoration is associated with increased mortality/morbidity, specific interventions targeted at better retention in care are urgently required.

Factors Affecting Virological Outcome When First-Line Antiretroviral Therapy Is Reintroduced After Unplanned Interruption

There is no guideline concerning choice of antiretroviral therapy (ART) for HIV-infected patients after unplanned interruption. We conducted a retrospective cohort study of HIV-infected patients reintroduced to first-line ART after having unplanned interruption for at least 1 month. Viral load was evaluated at 6 to 18 months after the reintroduction. There were 100 patients included in our study, and 55 of them achieved virological success. History of single interruption (adjusted odds ratio [aOR] 5.51%, 95% confidence interval [CI] 1.82-16.68, P = .003) and CD4 count ≥200 cell/mm³ at the time of reintroduction (aOR 4.33, 95% CI 1.14-16.39, P = .031) increased likelihood to achieve virological success.

Determinants of loss to care and risk of clinical progression in PLWH who are re-engaged in care after a temporary loss

The risk of developing AIDS is elevated not only among those with a late HIV diagnosis but also among those lost to care (LTC). The aims were to address the risk of becoming LTC and of clinical progression in LTC patients who re-enter care. Patients were defined as LTC if they had no visit for ≥ 18 months. Of these, persons with subsequent visits were defined as re-engaged in care (RIC). Factors associated with becoming LTC and RIC were investigated. The risk of disease progression was estimated by comparing RIC with patients continuously followed. Over 11,285 individuals included, 3962 became LTC, and of these, 1062 were RIC. Older age, presentation with AIDS and with higher HIV-RNA were associated with a reduced risk of LTC. In contrast, lower education level, irregular job, being an immigrant and injecting-drug user were associated with an increased LTC probability. Moreover, RIC with HIV-RNA > 200 copies/mL at the re-entry had a higher risk of clinical progression, while those with HIV-RNA ≤ 200 copies/mL had a higher risk of only non-AIDS progression. Patients re-entering care after being LTC appeared to be at higher risk of clinical progression than those continuously in care. Active strategies for re-engagement in care should be promoted.

Does transient cART started during primary HIV infection undermine the long-term immunologic and virologic response on cART resumption?

Background

We explored the impact of transient cART started during the primary HIV-infection (PHI) on the long-term immunologic and virologic response on cART resumption, by comparison with treatment initiation during the chronic phase of HIV infection (CHI).

Methods

We analyzed data on 1450 patients enrolled during PHI in the ANRS PRIMO cohort between 1996 and 2013. “Treatment resumption” was defined as at least 3 months of resumed treatment following interruption of at least 1 month of treatment initiated during PHI. “Treatment initiation during CHI” was defined as cART initiated ≥6 months after PHI. The virologic response to resumed treatment and to treatment initiated during CHI was analyzed with survival models. The CD4 cell count dynamics was modeled with piecewise linear mixed models.

Results

136 patients who resumed cART for a median (IQR) of 32 (18–51) months were compared with 377 patients who started cART during CHI for a median of 45 (22–57) months. Most patients (97%) achieved HIV-RNA <50 cp/mL after similar times in the two groups. The CD4 cell count rose similarly in the two groups during the first 12 months. However, after 12 months, patients who started cART during CHI had a better immunological response than those who resumed cART (p = 0.01); therefore, at 36 months, the gains in √CD4 cells/mm³ and CD4% were significantly greater in patients who started treatment during CHI.

Conclusion

These results suggest that interruption of cART started during PHI has a significant, albeit modest negative impact on CD4 cell recovery on cART resumption.

Influence of lifelong cumulative HIV viremia on long-term recovery of CD4+ cell count and CD4+/CD8+ ratio among patients on combination antiretroviral therapy

OBJECTIVE

We explored the impact of lifelong cumulative HIV viremia on immunological recovery during antiretroviral therapy, according to the timing of treatment initiation.

METHODS

We estimated lifelong cumulative HIV viremia in patients followed in the ANRS PRIMO cohort since primary infection, including 244 patients who started treatment during PHI and had at least one treatment interruption, and 218 patients who started treatment later but with no interruptions. The impact of cumulative viremia on current immunological status was analysed using linear and logistic regression models.

RESULTS

At the last visit on treatment, median CD4 cell count was 645 cells/μl in the early/intermittent treatment group (median time from infection 9.5 years, 4.8 years of continuous treatment since last resumption), and 654 cells/μl in the deferred/continuous treatment group (median time from infection 6.1 years, 3.0 years of continuous treatment). Only 36.1 and 39.8% of patients achieved a CD4/CD8 ratio of more than 1, respectively. Current CD4 cell count was not associated with cumulative HIV viremia in either group. In contrast, patients with high cumulative HIV viremia (>66th percentile vs. <33rd percentile) were less likely to achieve a CD4/CD8 ratio of more than 1 (26.8 vs. 43.3%, P = 0.003), even after controlling for the baseline CD4/CD8 ratio, treatment duration, sex and age. Much higher CD4 cell count and CD4/CD8 ratio were reached in early/continuous treatment, that is low viremia exposure group.

CONCLUSION

Our results underline the critical need in early-treated patients to maintain adherence, in order to limit cumulative HIV viremia and optimize immunological recovery, notably the CD4/CD8 ratio.

Blunted response to combination antiretroviral therapy in HIV elite controllers: an international HIV controller collaboration

Objective

HIV “elite controllers” (ECs) spontaneously control viral load, but some eventually require combination antiretroviral treatment (cART), due to a loss of viral control or a decline in CD4 T-cell counts. Here we studied the CD4 T-cell count dynamics after cART initiation among 34 ECs followed in U.S. and European cohorts, by comparison with chronically viremic patients (VIRs).

Methods

ECs were defined as patients with at least ≥5 viral load (VL) measurements below 400 copies/mL during at least a 5-year period despite never receiving ART and were selected from the French ANRS CO18 cohort, the U.S. SCOPE cohort, the International HIV Controllers study and the European CASCADE collaboration. VIRs were selected from the ANRS COPANA cohort of recently-diagnosed (<1 year) ART-naïve HIV-1-infected adults. CD4 T-cell count dynamics after cART initiation in both groups were modelled with piecewise mixed linear models.

Results

After cART initiation, CD4 T-cell counts showed a biphasic rise in VIRs with: an initial rapid increase during the first 3 months (+0.63/month), followed by +0.19/month. This first rapid phase was not observed in ECs, in whom the CD4Tc count increased steadily, at a rate similar to that of the second phase observed in VIRs. After cART initiation at a CD4 T-cell count of 300/mm³, the estimated mean CD4 T-cell gain during the first 12 months was 139/mm³ in VIRs and 80/mm³ in ECs (p = 0.048).

Conclusions

cART increases CD4 T-cell counts in elite controllers, albeit less markedly than in other patients.

Taking stock of infections and antibiotic resistance in the elderly and long-term care facilities: A survey of existing and upcoming challenges

Treating elderly patients with infections represents one of the greatest challenges to health-care providers. Older adults are the largest growing sector of the population and suffer excessively from infectious diseases such as pneumonia, urinary tract infections (UTIs), and skin and soft-tissue infections. Often because of disabilities, the elderly require treatment of infectious diseases in long-term care facilities (LTCFs). As a result of antibiotic use, LTCFs have become "reservoirs of resistance" and multi-drug resistant (MDR) pathogens are frequently recovered. Clinicians also need to be aware of the impairment of immune function and other emerging chronic infections (HIV, HCV) that are now present in the elderly. Despite vigilance regarding this issue, delays in diagnosis and initiation of therapy are common. This article reviews the changing landscape of infections in the elderly and the challenge these syndromes present in the context of an increasing older population that requires dedicated resources.

Unstructured treatment interruption of antiretroviral therapy in clinical practice: a systematic review

OBJECTIVE

To characterize the frequency, reasons, risk factors, and consequences of unstructured anti-retroviral treatment interruptions.

METHOD

Systematic review.

RESULTS

Seventy studies were included. The median proportion of patients interrupting treatment was 23% for a median duration of 150 days. The most frequently reported reasons for interruptions were drug toxicity, adverse events, and side-effects; studies from developing countries additionally cited treatment costs and pharmacy stock-outs as concerns. Younger age and injecting drug use was a frequently reported risk factor. Other risk factors included CD4 count, socioeconomic variables, and pharmacy stock outs. Treatment interruptions increased the risk of death, opportunistic infections, virologic failure, resistance development, and poor immunological recovery. Proposed interventions to minimize interruptions included counseling, mental health services, services for women, men, and ethnic minorities. One intervention study found that the use of short message service reminders decrease the prevalence of treatment interruption from 19% to 10%. Finally, several studies from Africa stressed the importance of reliable and free access to medication.

CONCLUSION

Treatment interruptions are common and contribute to worsening patient outcomes. HIV/AIDS programmes should consider assessing their causes and frequency as part of routine monitoring. Future research should focus on evaluating interventions to address the most frequently reported reasons for interruptions.

NK-cell phenotype at interruption underlies widely divergent duration of CD4+-guided antiretroviral treatment interruption

Long-term side effects may represent a relevant burden of antiretroviral treatment (ART) in HIV-infected patients with good CD4 immune reconstitution over extended time spans. CD4-guided treatment interruption (TI) has been evaluated to address this point and may result in a wide spectrum of time off ART in different patient cohorts. We studied whether differences in innate immune responses, in particular NK cells, are associated to patterns of longer (LoTI) or a shorter (ShTI) TI. Clinical cohort parameters were analyzed on a group of patients widely diverging for TI duration (<9 versus >18 months) on samples before TI, including NK-cell analysis and function by natural cytotoxicity receptor (NCR)-triggered γ-IFN production. Although persistently reduced NCR expression (NKp30) and function were observed in both LoTI and ShTI patients on ART compared with healthy donors, relevant differences were observed at baseline TI in those patients who subsequently developed LoTI course. Lower expression of NKG2D and NKp46 on NK cells. This also translates in reduced γ-IFN production in redirected functional assays. Thus, differences in innate immune balance exist during ART, may be associated to differential control of HIV infection and their understanding could explain clinical differences in individual patients that are not reflected by CD4(+) cell counts alone.