Neuropsychiatric and Laboratory Outcomes of Hepatitis C Treatment in an Early-Treated HIV Cohort in Thailand

Background Hepatitis C virus (HCV) coinfection may further compromise immunological and cognitive function in people with HIV (PWH). This study compared laboratory and neuropsychiatric measures across the periods of HCV seroconversion and direct-acting antiviral (DAA) therapy with sustained virologic response (SVR) among PWH who initiated antiretroviral therapy (ART) during acute HIV infection (AHI) and acquired HCV after 24 weeks of ART. Methods Participants from the RV254 AHI cohort underwent paired laboratory and neuropsychiatric assessments during regular follow-up. The former included measurements of CD4 + and CD8 + T-cell counts, HIV RNA, liver enzymes, and lipid profiles. The latter included the Patient Health Questionnaire-9 (PHQ-9), Distress Thermometer (DT), and a 4-test cognitive battery that evaluated psychomotor speed, executive function, fine motor speed and dexterity. The raw scores in the battery were standardized and averaged to create an overall performance (NPZ-4) score. Parameters of HCV-coinfected participants were compared across HCV seroconversion and DAA treatment groups. Results Between 2009 and 2022, 79 of 703 RV254 participants acquired HCV after ≥ 24 weeks of ART; 53 received DAA, and 50 (94%) achieved SVR. All participants were Thai males (median age: 30 years); 34 (68%) denied past intravenous drug use, and 41 (82%) had a history of other sexually transmitted infections during follow-up. Following SVR, aspartate transferase (AST) and alanine transaminase (ALT) decreased (p < 0.001), while total cholesterol, low-density lipoprotein, and triglycerides increased (p < 0.01). The median CD4+/CD8 + ratio increased from 0.91 to 0.97 (p = 0.012). NPZ-4 improved from 0.75 to 0.91 (p = 0.004). The median DT score increased from 1.7 to 2.7 (p = 0.045), but the PHQ-9 score remained unchanged. Conclusion HCV coinfection is common in this group of high-risk PWH, highlighting the need for regular screening, early diagnosis, and treatment. There was a modest improvement in the CD4+/CD8 + T-cell ratio and cognitive performance after DAA therapy in patients who achieved SVR. Future studies should examine potential neuropsychiatric impacts during early HCV infection as well as the longer-term neuropsychiatric outcomes after DAA treatment with SVR.


Background
HIV and Hepatitis C virus (HCV) share common modes of transmission, including sexual contact, needlesharing during intravenous drug use (IVDU), and blood product transfusion.HCV coinfection is reported in up to 6.2% of people with HIV (PWH) [1].The odds of HCV infection are 6 times greater among PWH than among individuals without.Compared to HIV monoinfection and HCV monoinfection, HIV/HCV coinfection is associated with greater risks of mortality, liver failure and extrahepatic manifestations, including cognitive and affective symptoms [2][3][4][5][6], indicating that disease progression is accelerated in individuals with dual infections.
The use of direct-acting antivirals (DAAs) averts the devastating consequences of chronic HCV infection, as evidenced by a high cure rate (sustained virologic response, SVR) and favorable safety pro les [7].DAAs inhibit the nonstructural proteins that are responsible for viral replication.Remarkably, DAAs are effective regardless of age, sex, previous treatment experience, or stage of liver brosis [8].Improvements in HCV-related extrahepatic conditions after DAA therapy and SVR [9] were observed in HCVmonoinfected as well as HIV/HCV-coinfected individuals [10].
To date, most HCV treatment outcome studies focusing on immunologic and neuropsychiatric outcomes in HIV/HCV-coinfected patients have been based on individuals with chronic HIV infection, heterogeneous HIV suppression status, and often, an unknown duration of HCV infection [7,8].Moreover, only a few of them provided a concurrent account of changes before and after HCV seroconversion prior to HCV treatment.This study examined the changes in laboratory and neuropsychiatric parameters during the periods of HCV seroconversion and DAA therapy with SVR among research participants from a Thai acute HIV infection (AHI) cohort who were on antiretroviral therapy (ART).

Study design and participants
The study participants were from the RV254 AHI cohort study in Bangkok, Thailand, which enrolled individuals with Fiebig I-V AHI [11].RV254 participants typically commenced ART within a median of 3 days post enrollment and were longitudinally followed.They were screened for HCV infection every 48 weeks using an HCV-antibody test, and active infection was con rmed through HCV RNA measurement via the Xpert HCV Assay (Cepheid, Sunnyvale, CA).The study protocol was approved by the institutional review boards of all relevant collaborating institutions.All participants provided written informed consent.

Participant selection
The analysis included participants who met the following criteria: (1) tested negative for HCV antibody at enrollment; (2) had ≥ 24 weeks of ART with suppressed HIV RNA levels (< 50 copies/ml) before initiating DAA treatment; (3) achieved SVR with undetectable HCV RNA ≥ 12 weeks following a standard course of DAA treatment; and (4) completed paired laboratory and neuropsychiatric assessments before and after DAA therapy with SVR, based on the RV254 study protocol (see below).

Laboratory and clinical investigations
Blood tests included HIV-related immunologic and virologic parameters (plasma HIV RNA, CD4 + and CD8 + T-cell counts), complete blood count, liver enzyme levels (aspartate transferase (AST) and alanine transaminase (ALT)) and lipid pro le (total cholesterol, low-density lipoprotein (LDL) and triglyceride).Additionally, nontreponemal syphilis testing and nucleic acid ampli cation tests for chlamydia and gonorrhea are performed every 24 and 48 weeks, respectively.Participants are also screened for peripheral neuropathy by research clinicians every 48 weeks (Supplementary Table 1).

Neuropsychiatric assessments
All RV254 participants underwent neuropsychiatric assessments at enrollment; at 12, 24 and 48 weeks; and every 48 weeks thereafter.Mood assessments included the Patient Health Questionnaire-9 (PHQ-9) and the Distress Thermometer (DT).Both have been validated for use in Thailand [12][13][14].The PHQ-9 is a 9-item survey of depressive symptoms (score range 0-27) derived from the DSM-IV [15].Total scores ≥ 10 and ≥ 15 indicate moderate and moderate-severe depression, respectively [15].The DT is a selfreported measure of emotional distress that is analogous to a visual analog scale with a range from 0 to 10 [16].
Cognitive assessment was based on a 4-test battery that measured motor speed and dexterity (nondominant hand Grooved Pegboard test; Lafayette Instrument Company, Lafayette, IN, USA), psychomotor speed (Color Trails 1 and Trail Making A; PAR, Inc., Lutz, FL, USA), and executive functioning (Color Trails 2; PAR, Inc., Lutz, FL, USA).Raw scores were standardized to z-scores using Thai normative data [17], which were averaged to create an overall performance (NPZ-4) score.Individual and overall test performances were included in the analyses.

Data analysis
The paired laboratory and neuropsychiatric measures of the participants with HCV were assessed across two separate periods, speci cally in relation to HCV seroconversion and DAA therapy: (1)

Results
Between May 2009 and July 2022, 109 (15.5%) out of 703 RV254 participants were diagnosed with HCV: 16 tested positive for anti-HCV antibody at enrollment (week 0), 12 seroconverted between weeks 1 and 24, and 79 were diagnosed after 24 weeks of ART; 2 withdrew from the study at the time of analysis.
Among the 79 participants who seroconverted after 24 weeks of ART, 53 completed DAA therapy with HCV RNA level measurements at least 3 months after DAA therapy.Of these, 50 (94%) achieved SVR and were included in the current analysis (Fig. 1).
None reported DAA-related adverse events.

Discussion
We previously reported an HCV epidemic among HIV-infected men who have sex with men (MSM) in Bangkok, Thailand [18,19].We observed a 16% prevalence of HCV infection in this young, MSMpredominant AHI cohort, with an 11% cumulative incidence of HCV seroconversion among participants on stable (> 24 weeks) ART.In comparison, a global systematic study reported that the prevalence of HCV coinfection in HIV-infected MSM is approximately 6.4% [1].Notably, the main route of HCV transmission in our cohort was likely through sexual behavior, primarily anal sex, often in the context of substance use and group sex [18].While 32% of the study participants reported a history of IVDU, problematic substance use and substance dependence were rare, as indicated by clinician interviews during follow-up visits.
Consistent with the high e cacy and safety pro le of DAAs [7], the treatment success rate was 94%, and DAA-related adverse events were not observed in this study.The levels of liver enzymes decreased post-DAA, re ecting the resolution of HCV-related hepatic in ammation.Previous studies reported increases in hemoglobin levels, total leukocyte counts, and platelet counts after SVR [20][21][22], but these changes were not observed here.The hematological bene ts reported in prior studies could be secondary to improvements in liver brosis, portal hypertension, and anemia associated with chronic illness after SVR [23].These hematological changes were not observed in our cohort, most likely because our participants were relatively young MSM who, prior to DAA initiation, had normal hematological parameters and lacked major hepatic complications.In line with the results of prior studies that included HCV-monoinfected [24][25][26] and HIV/HCV-coinfected participants [27], we noted elevations in total cholesterol, triglyceride, and LDL levels after SVR.HCV is hypothesized to induce hypolipidemia by stimulating LDL receptor expression and modulating proteins involved in liver steatosis [27,28].HCV eradication may therefore reverse these processes, leading to paradoxical increases in serum lipid levels.

HIV-related immune and virologic parameters
HCV infection has been reported to negatively impact the ART response and CD4 + T-cell recovery in ARTnaïve PWH [29].HCV infection induces CD8 + T-cell activation and may hamper CD8 + T-cell downregulation in PWH on ART [30], thereby worsening CD4+/CD8 + T-cell ratio inversion [31].Two previous studies reported unchanged CD4 + T-cell counts post-SVR [32,33].While two studies reported a reduction in the CD8 + T-cell count post-SVR [32,34], only one reported a concomitant improvement in the CD4+/CD8 + T-cell ratio [34].In this study, the CD4+/CD8 + T-cell ratio modestly increased without statistically signi cant changes in CD4 + and CD8 + T-cell counts in the context of stable HIV suppression between pre-DAA and post-DAA visits.Nonetheless, in the absence of a comparison group of HIVmonoinfected and HCV-monoinfected individuals, it is challenging to disentangle the effects of DAA treatment versus antiretroviral therapy on CD4+/CD8 + T-cell recovery.

Neurological and Neuropsychiatric Outcomes
Neurological complications, such as cognitive impairment, mood disorders, and peripheral neuropathy, have been reported in individuals with HCV monoinfection and HIV/HCV coinfection [35][36][37][38].In this study, peripheral neuropathy was uncommon and was identi ed in 2 participants (4%) who exhibited mild impairment of distal vibration sense within six months of HCV seroconversion.The neuropathy symptoms were likely HCV-related given their temporal relationship, stable HIV suppression, and normal folate, vitamin B12, and glycosylated hemoglobin (HbA1c) levels.In an HCV monoinfection study, neuropathy symptoms improved in half of the participants after DAA therapy [39], whereas one participant in our study experienced resolved neuropathy symptoms nine months after DAA therapy.
Surprisingly, DT scores increased post-DAA in this study compared to a reduction in a prospective study with 90 HCV-monoinfected participants [40].Nonetheless, the median DT score at the post-DAA visit remained well below the commonly referred cutoff score (≥ 4), which signi es distress with clinical signi cance [41].Notably, this change was not associated with worsening of the PHQ-9 score.
HCV infection might impact cognition [42,43] through direct neurotoxicity, neuroin ammation, and hepatic encephalopathy [42][43][44].HCV/HIV coinfection has been associated with worse cognition than either HIV or HCV monoinfection [45][46][47].Most studies have shown signi cant cognitive improvement post-DAA with SVR, especially in visual learning/memory, executive functions, verbal uency, processing speed, and motor skills [47][48][49].In our study, both the composite score and z-score of the Trail Making A test (a test of psychomotor speed) improved post-DAA.Notably, both indices were within the normal range before DAA, and the magnitude of improvement was modest and within the standard error of measurement.
To our knowledge, this is the rst study that concurrently offers a longitudinal assessment of laboratory, cognitive and mood outcomes in PWH throughout the phases of HCV seroconversion and DAA treatment.
The analysis was based on a longitudinal cohort of PWH who initiated ART during acute HIV and acquired HCV while on stable ART for more than 24 weeks.The present study design has partially addressed several methodological confounders of previous studies on cognitive outcomes after DAA treatment and HCV eradication.First, practice effects lead to improved performance on several NP measures, especially between the rst and second test exposures [50].In this study, participants completed the same cognitive battery multiple times and passed the critical phase of practice effects before DAA therapy was initiated, limiting the impact on test performance.Second, disentangling the potential cognitive bene ts of HCV eradication from those of ART on HIV infection is challenging, as cognitive improvement related to the latter may take weeks to months before reaching a plateau [51].
Similarly, CD4 + and CD8 + T-cell counts continuously evolve months to years after ART initiation [52].In this study, the potential immunological and cognitive bene ts of ART were minimized by the stable use of ART for more than 2 years before initiating DAA treatment in most of the participants.The initially statistically unchanged NPZ-4 and CD4+/CD8 + scores after HCV seroconversion and the subsequent improvement in these parameters after DAA treatment with SVR raise the question of whether the observed improvement is related to DAA treatment and HCV eradication.
Limitations of this study include the sample size, short follow-up duration, male-only setting, the absence of liver elastography to grade the severity of liver disease, and the lack of HCV-monoinfected controls to determine whether the observed changes are HIV/HCV-coinfection speci c.

Conclusion
Consistent with existing reports, this study highlighted the high frequency of HCV coinfection among young MSM with HIV in our locality.These patients responded well to DAA treatment, achieving a high rate of HCV eradication.These ndings indicate the necessity of incorporating routine HCV screening for early diagnosis, along with educational materials on HCV prevention, into ongoing HIV/AIDS programs.
We observed modest longitudinal improvements in cognitive test performance and the CD4+/CD8 + T-cell ratio after DAA therapy and SVR but not during the period after HCV seroconversion.The discordant outcomes between the two periods may suggest an early neuropsychiatric impact of HCV infection, which was subsequently reversed by prompt initiation of HCV treatment and eradication.Future studies with both HIV-and HCV-monoinfected controls should focus on the early neuropsychiatric impacts of HCV infection as well as the longer-term neuropsychiatric outcomes after DAA treatment with SVR.

List Of Abbreviations
ART -antiretroviral therapy DAA -direct-acting antiviral

Funding
The participants were from the RV254/SEARCH010, which is supported by cooperative agreements between HCV diagnosis and DAA initiation, weeks 55(29, 69)    ART Regimen prior to HCV seroconversion, n (%)

(Figure 1 Study
Figures

Table 2
Laboratory and clinical outcomes across HCV seroconversion and DAA treatment with SVR treatment and SVR.On the other hand, the median CD4+/CD8 + T-cell ratio was not signi cantly different after HCV seroconversion but increased from 0.91 [IQR 0.73-1.1] to 0.97 [IQR 0.76-1.29](p = 0.012) after DAA treatment and SVR.The plasma HIV suppression rate remained unchanged throughout the two periods.