Korea HIV/AIDS Cohort Study: study design and baseline characteristics

Smoothed quantile residual life regression analysis with application to the Korea HIV/AIDS cohort study

BACKGROUND

The residual life of a patient with human immunodeficiency virus (HIV) is of major interest to patients and their physicians. While existing analyses of HIV patient survival focus mostly on data collected at baseline, residual life analysis allows for dynamic analysis based on additional data collected over a period of time. As survival times typically exhibit a right-skewed distribution, the median provides a more useful summary of the underlying distribution than the mean. In this paper, we propose an efficient inference procedure that fits a semiparametric quantile regression model assessing the effect of longitudinal biomarkers on the residual life of HIV patients until the development of dyslipidemia, a disease becoming more prevalent among those with HIV.

METHODS

For estimation of model parameters, we propose an induced smoothing method that smooths nonsmooth estimating functions based on check functions. For variance estimation, we propose an efficient resampling-based estimator. The proposed estimators are theoretically justified. Simulation studies are used to evaluate their finite sample performances, including their prediction accuracy. We analyze the Korea HIV/AIDS cohort study data to examine the effects of CD4 (cluster of differentiation 4) cell count on the residual life of HIV patients to the onset of dyslipidemia.

RESULTS

The proposed estimator is shown to be consistent and normally distributed asymptotically. Under various simulation settings, our estimates are approximately unbiased. Their variances estimates are close to the empirical variances and their computational efficiency is superior to that of the nonsmooth counterparts. Two measures of prediction performance indicate that our method adequately reflects the dynamic character of longitudinal biomarkers and residual life. The analysis of the Korea HIV/AIDS cohort study data shows that CD4 cell count is positively associated with residual life to the onset of dyslipidemia but the effect is not statistically significant.

CONCLUSIONS

Our method enables direct prediction of residual lifetimes with a dynamic feature that accommodates data accumulated at different times. Our estimator significantly improves computational efficiency in variance estimation compared to the existing nonsmooth estimator. Analysis of the HIV/AIDS cohort study data reveals dynamic effects of CD4 cell count on the residual life to the onset of dyslipidemia.

Assessment of Disease Burden and Immunization Rates for Vaccine-Preventable Diseases in People Living with HIV: The Korea HIV/AIDS Cohort Study

BACKGROUND

Prophylactic immunization is important for human immunodeficiency virus (HIV)-infected patients; however, there are insufficient data on the burden of vaccine-preventable diseases (VPDs), vaccination rates, and factors influencing vaccination.

MATERIALS AND METHODS

The incidence and prevalence of VPDs in HIV-infected patients between 2006 and 2017 were estimated using the Korean HIV/acquired immune deficiency syndrome (AIDS) cohort database. In addition, we evaluated the vaccination rates and influencing factors for vaccination in HIV-infected patients through multilevel analysis of clinico-epidemiological factors, immune status, and psychological status. A questionnaire survey was conducted among experts to determine whether they recommend vaccination for HIV-infected patients.

RESULTS

The incidence rates of hepatitis B virus (HBV) infection, herpes zoster, and anogenital warts were 1.74, 7.38, and 10.85 per 1,000 person-years, respectively. The prevalence of HBV infection and anogenital warts at enrollment was 4.8% and 8.6%, respectively, which increased to 5.3% and 12.0%, respectively, by 2017. In HIV-infected patients, HBV (21.7% in 2008, 56.3% in 2013, and 75.4% in 2017) and pneumococcal vaccination rates (3.0% in 2015, 7.6% in 2016, and 9.6% in 2017) increased annually, whereas the influenza vaccination rate remained similar by season (32.7 - 35.6%). In the multilevel analysis, peak HIV viral load (≥50 copies/mL: odds ratio [OR] = 0.64, 95% confidence interval [CI]: 0.44 - 0.93; reference, <50 copies/mL) was an influencing factor for pneumococcal vaccination, while nadir CD4 T-cell counts (200 - 350 cells/mm3: OR = 0.54, 95% CI: 0.38 - 0.76; <200 cells/mm3: OR = 0.89, 95% CI: 0.62 - 1.28; reference, ≥350 cells/mm3) was an influencing factor for HBV vaccination. Influenza vaccination was associated with male sex (OR = 1.94) and the number of antiretroviral therapy (ART) regimen change (OR = 1.16), but was not significantly associated with HIV viral load or CD4 T-cell counts. Most experts responded that they administer hepatitis A virus, HBV, pneumococcal, and influenza vaccines routinely, but not human papillomavirus (12.9%) or herpes zoster vaccines (27.1%).

CONCLUSION

The burden of vaccine-preventable diseases was quite high in HIV-infected patients. Nadir CD4 T-cell counts, peak HIV viral loads, and the number of ART regimen change are significant factors related to vaccination. Considering the low vaccination rates for VPDs, there was a discordance between experts' opinions and real clinical practice in the medical field.

Attachment Insecurity and Stigma as Predictors of Depression and Anxiety in People Living With HIV

OBJECTIVE

The purpose of this study was to examine whether attachment insecurity, stigma, and certain demographic and medical factors predict depression and anxiety in people living with HIV (PLWH).

METHODS

Participants were 147 PLWH who visited the outpatient infection clinic in Kyungpook National University Hospital (KNUH; Daegu, South Korea) between June 2020 and January 2021. We measured HIV-related stigma, attachment anxiety and avoidance, depressive symptoms, and anxiety symptoms.

RESULTS

Logistic regression analysis showed that unemployment, longer time receiving antiretroviral therapy, higher attachment avoidance, and higher attachment anxiety were significant predictors of depression. Results also showed that longer time receiving antiretroviral therapy, higher attachment anxiety, and concern with public attitudes were significant predictors of anxiety.

CONCLUSION

In addition to education to reduce public stigma, interventions to reduce PLWH's self-stigma should continue. We suggest attachment-based psychotherapy as an effective intervention to improve PLWH's mental health.

Effect of characteristics on the clinical course at the initiation of treatment for human immunodeficiency virus infection using dimensionality reduction

The beginning of human immunodeficiency virus (HIV) infection treatment depends on various factors, which are significantly correlated with the initial CD4 cell number. However, a covariate correlation between these factors may not reflect the correct outcome variable. Thus, we evaluated the effects of a combination of fixed factors (reduced dimensions), which determine when to start treatment for the first time, on short-term outcome, long-term outcome, and survival, considering correlations between factors. Multiple correspondence analysis was performed on variables obtained from 925 patients who participated in a Korean HIV/acquired immunodeficiency syndrome cohort study (2006-2017). Five reduced dimension groups were derived according to clinical data, viral load, CD4 cell count at diagnosis, initial antiretroviral therapy, and others. The dimension group with high initial viral loads (55,000 copies/mL) and low CD4 cell counts (< 200 cells/mm³) should start treatment promptly after diagnosis. Groups with high initial CD4 cell counts (> 350 cells/mm³) that did not require immediate treatment according to previous guidelines had a higher failure rate for long-term relative CD4 recovery. Our results highlight the importance of early diagnosis and treatment to positively influence long-term disease outcomes, even if the initial immune status is poor, given the patient's combination of early diagnostic symptoms.

Predictors Associated With HIV Status Non-Disclosure in Korea

BACKGROUND

Human immunodeficiency virus (HIV) disclosure provides personal support to people living with HIV/acquired immunodeficiency syndrome (PLWH). In addition, it has important implications for disease prevention and treatment. Research on disclosure has been conducted worldwide; however, data from South Korea are insufficient. The purpose of this study was to examine whether certain demographic, medical, and psychosocial factors act as predictors of HIV serostatus non-disclosure among PLWH in South Korea.

METHODS

Participants consisted of 147 PLWH who visited the outpatient infection clinic between June 2020 and January 2021. Demographics, medical factors, HIV-related stigma, and depressive and anxiety symptoms were measured.

RESULTS

The overall disclosure rate among participants was 61.2%. Logistic regression analysis showed that lower depression (odds ratio [OR], 0.918; P = 0.021) and higher disclosure concerns (OR, 1.133; P = 0.004) were significant predictors of non-disclosure. Further, married state was a major predictor of non-disclosure when single referred (OR, 3.002; P = 0.024); however, divorce, separation, and widowed status had no significant consequences.

CONCLUSION

In South Korea, the rate of HIV disclosure is lower than in other countries. The higher disclosure concerns, lower depression and married state were suggested to be important predictors of HIV non-disclosure. High level of perceived stigma and experienced discrimination of PLWH may have affected the results. The social atmosphere linking sexual promiscuity and disease may also have influenced these results. Nationwide efforts should continue to reduce the overall stigma and create a social environment where PLWH can feel safe to disclose their disease conditions.

Effect of single tablet regimen on prescription trends for treatment-naïve patients with HIV/AIDS in Korea

Single-tablet regimens (STRs) should be considered for patients with HIV/AIDS to increase medication compliance and improve clinical outcomes. This study compared variations in the prescription trends between STRs and multiple-tablet regimens (MTRs) for treatment-naïve patients with HIV/AIDS after the approval of the new STRs, a proxy indicator for improvement in medication adherence. The medical and pharmacy claim data were retrospectively obtained from the Health Insurance Review and Assessment service, which contains basic information on the patients' sociodemographic characteristics and treatment information for the entire Korean population. From 2013 to 2018, a total of 6737 patients with HIV/AIDS were included. Most patients were men (92.8%, n = 6251) and insured through the National Health Insurance (95.1%, n = 6410). The mean number of pills in their antiretroviral treatment regimens decreased from 2.8 ± 1.2 in 2013 to 1.2 ± 1.0 in 2018. After the first STR (EVG/c/TDF/FTC) was approved in 2014, prescription transitions from MTR to STR were observed among more than 38% of patients. In 2018, most treatment-naïve patients were prescribed STRs (91.2%). There was a time lag for STR prescription trends in non-metropolitan hospitals compared with those in metropolitan cities. Our data provide a valuable perspective for evaluating ART regimen prescription patterns on a national scale.

The Incidence and Risk Factors of Renal Insufficiency among Korean HIV infected Patients: The Korea HIV/AIDS Cohort Study

Renal insufficiency is one of the common issues in people living with human immunodeficiency virus (PLHIV). We studied the incidence and risk factors for renal insufficiency in male PLHIV using the Korea HIV/acquired immunodeficiency syndrome (AIDS) Cohort Study. Among the 830 enrolled patients, 32 (3.9%) cases of renal insufficiency occurred over 9576 patient-years of follow-up. The incidence of renal insufficiency in HIV-infected men in this study was 3.3 per 1000 patient-years. Diabetes mellitus, dyslipidemia, tenofovir or non-nucleoside reverse transcriptase inhibitor exposure for >1 year, and AIDS-defining illness were risk factors for renal insufficiency.

Comparison of Three Cardiovascular Risk Scores among HIV-Infected Patients in Korea: The Korea HIV/AIDS Cohort Study

Background

We investigated cardiovascular disease (CVD), risk factors for CVD, and applicability of the three known CVD risk equations in the Korean human immunodeficiency virus/ Acquired Immune Deficiency Syndrome (HIV/AIDS) cohort.

Materials and Methods

The study parcitipants were HIV-infected patients in a Korean HIV/AIDS cohort enrolled from 19 hospitals between 2006 and 2017. Data collected at entry to the cohort were analyzed. The 5-year CVD risk in each participant was calculated using three CVD risk equations: reduced CVD prediction model of HIV-specific data collection on adverse effects of anti-HIV drugs (R-DAD), Framingham general CVD risk score (FRS), and Korean Coronary Heart Disease Risk Score (KRS).

Results

CVD events were observed in 11 of 586 HIV-infected patients during a 5-year (median) follow-up period. The incidence of CVD was 4.11 per 1,000 person-years. Older age (64 vs. 41 years, P = 0.005) and diabetes mellitus (45.5% vs. 6.4%, P <0.001) were more frequent in patients with CVD. Using R-DAD, FRS, and KRS, 1.9%, 2.4%, and 0.7% of patients, respectively, were considered to have a very high risk (≥10%) of 5-year CVD. The discriminatory capacities of the three prediction models were good, with c-statistic values of 0.829 (P <0.001) for R-DAD, 0.824 (P <0.001) for FRS, and 0.850 (P = 0.001) for KRS.

Conclusion

The FRS, R-DAD, and KRS performed well in the Korean HIV/AIDS cohort. A larger cohort and a longer period of follow-up may be necessary to demonstrate the risk factors and develop an independent CVD risk prediction model specific to Korean patients with HIV.

A comparison of medication adherence and viral suppression in antiretroviral treatment-naïve patients with HIV/AIDS depending on the drug formulary

Antiretroviral treatment (ART) adherence is highlighted in management of patients living with human immunodeficiency virus. In South Korea, ART medication research has rarely been conducted due to the low economic burden associated with government-funded treatment. This cross-sectional study aimed to compare the pill burden impact between ART regimen compliance and HIV-RNA viral load suppression. Data were collected from 2008 to 2016 at a general hospital in South Korea. A total of 210 HIV/AIDS treatment-naïve patients were grouped as follows: single-tablet regimen (STR, one tablet/day), mild pill burden (two-four tablets/day), and heavy pill burden (≥ five tablets/day). Patients were analyzed according to gender, age at index date, medical insurance type, comorbidities, depression, HIV/AIDS disease burden as indicated by HIV-RNA viral load and CD4, and laboratory variables. In a multivariate logistic regression model, the STR group demonstrated adherence 5.10 times more often than the heavy pill burden group. Females and patients with an initial viral load of 500,000 or more were 0.090- and 0.040-fold less adherent to the ART regimen. Among these patients, 95% or more of the MPR group were 7.38 times more likely to have a lower limit of detection (LLOD) of viral load suppression. The highest initial viral load group was 0.090-fold less likely to have an LLOD than the reference group. These results suggest that a single-tablet regimen could improve medication adherence and the clinical virologic outcome. Therefore, general population research on ART adherence and polypharmacy is needed.

Prospective cohort data quality assurance and quality control strategy and method: Korea HIV/AIDS Cohort Study

OBJECTIVES

The aim of effective data quality control and management is to minimize the impact of errors on study results by identifying and correcting them. This study presents the results of a data quality control system for the Korea HIV/AIDS Cohort Study that took into account the characteristics of the data.

METHODS

The HIV/AIDS Cohort Study in Korea conducts repeated measurements every 6 months using an electronic survey administered to voluntarily consenting participants and collects data from 21 hospitals. In total, 5,795 sets of data from 1,442 participants were collected from the first investigation in 2006 to 2016. The data refining results of 2015 and 2019 were converted into the data refining rate and compared.

RESULTS

The quality control system involved 3 steps at different points in the process, and each step contributed to data quality management and results. By improving data quality control in the pre-phase and the data collection phase, the estimated error value in 2019 was 1,803, reflecting a 53.9% reduction from 2015. Due to improvements in the stage after data collection, the data refining rate was 92.7% in 2019, a 24.21%p increase from 2015.

CONCLUSIONS

Despite this quality management strategy, errors may still exist at each stage. Logically possible errors for the post-review refining of downloaded data should be actively identified with appropriate consideration of the purpose and epidemiological characteristics of the study data. To improve data quality and reliability, data management strategies should be systematically implemented.

Estimation of the Number of HIV Infections and Time to Diagnosis in the Korea

BACKGROUND

Statistical data of undiagnosed people living with human immunodeficiency virus (PLHIV) are of great importance to human immunodeficiency virus (HIV) infection control. This study estimated the total number of PLHIV using nationwide claims data.

METHODS

This study used data of the incident HIV cases identified by the National Health Insurance System between 2009 and 2015. The number of patients with acquired immune deficiency syndrome (AIDS) was identified by diagnoses or prescription records. The estimated number of PLHIV and the time to diagnosis were calculated from the incident numbers of HIV and AIDS cases using the HIV Modeling Tool of the European Center for Disease Prevention and Control.

RESULTS

Between 2009 and 2015, a total of 7,033 PLHIV and 2,899 AIDS patients were diagnosed. In 2009, the number of incident HIV cases was 873 (460 AIDS patients), increasing to 995 (337 AIDS patients) in 2015. Besides, the estimated number of prevalent cases was 10,753 in 2009, compared to 14,880 in 2015. Patients visiting health facilities accounted for 42.9% (4,616/10,753) in 2009 and 64.1% (9,544/14,880) in 2015. In 2009, there were 8,363 (77.8%) undiagnosed HIV cases, experiencing a decline to 6,215 (41.8%) in 2015. It took a mean of 6.96 years to diagnose after HIV infection.

CONCLUSION

This study estimates the total burden of HIV infection in Korea for the first time using an internationally recognized HIV modeling tool. Claims data can be used to estimate the number of undiagnosed cases by identifying the total number of PLHIV and AIDS patients visiting health facilities.

Human Immunodeficiency Virus-Associated Gastrointestinal Kaposi's Sarcoma: A Case Report

Kaposi's sarcoma (KS) is a multicentric human immunodeficiency virus-associated neoplasm characterized by multiple vascular nodules in the skin, mucous membranes, and viscera. Gastrointestinal acquired immunodeficiency syndrome (AIDS)-related KS is the most common visceral involvement reported in disseminated disease. Here, we present the findings of a rare case of KS involving multiple organs with abdominal pain and active bleeding in the colon. Multiple intraluminal lesions were found in the terminal ileum, sigmoid colon, and rectum by ileocolonoscopy, and in the jejunum and ileum by fluoroscopy. Abdominopelvic CT revealed multiple enhanced flat lesions in the ileum and enlarged lymph nodes. The diagnosis was confirmed by histopathology, and antiretroviral therapy was initiated as the treatment of choice for KS. Owing to the increasing number of AIDS patients, it is essential for radiologists and clinicians to be aware of the imaging characteristics of KS to protect physicians from indiscriminate exposure to AIDS.

Epidemiological characteristics of HIV infected Korean: Korea HIV/AIDS Cohort Study

OBJECTIVES

To manage evidence-based diseases, it is important to identify the characteristics of patients in each country.

METHODS

The Korea HIV/AIDS Cohort Study seeks to identify the epidemiological characteristics of 1,442 Korean individuals with human immunodeficiency virus (HIV) infection (12% of Korean individuals with HIV infection in 2017) who visited 21 university hospitals nationwide. The descriptive statistics were presented using the Korea HIV/AIDS cohort data (2006-2016).

RESULTS

Men accounted for 93.3% of the total number of respondents, and approximately 55.8% of respondents reported having an acute infection symptom. According to the transmission route, infection caused by sexual contact accounted for 94.4%, of which 60.4% were caused by sexual contact with the same sex or both males and females. Participants repeatedly answered the survey to decrease depression and anxiety scores. Of the total participants, 89.1% received antiretroviral therapy (ART). In the initial ART, 95.3% of patients were treated based on the recommendation. The median CD4 T-cell count at the time of diagnosis was 229.5 and improved to 331 after the initial ART. Of the patients, 16.6% and 9.4% had tuberculosis and syphilis, respectively, and 26.7% had pneumocystis pneumonia. In the medical history, sexually transmitted infectious diseases showed the highest prevalence, followed by endocrine diseases. The main reasons for termination were loss to follow-up (29.9%) and withdrawal of consent (18.7%).

CONCLUSIONS

Early diagnosis and ART should be performed at an appropriate time to prevent the development of new infection.

Comparison of Characteristics and Survival between Prospective and Retrospective Korea Human Immunodeficiency Virus/Acquired Immune Deficiency Syndrome Cohort Studies

By comparing the data of prospectively and retrospectively enrolled cohorts, we evaluated whether the prospective cohort represented all patients in the retrospective cohort. The prospectively enrolled subjects were older and had lower CD4+ T cell counts, higher viral load. In addition, the initial antiretroviral treatment regimen of the prospective cohort consisted of less integrase strand transfer inhibitor-containing regimens. The 20-year survival rate was 51.8% in the prospective cohort and 84.6% in the retrospective cohort, respectively (P = 0.844). This study suggests the prospective cohort study may not represent all patients.