Loss to follow-up in the Australian HIV Observational Database

Brief Report: Mortality After Loss to Follow-Up-A Linkage Study of People Living With HIV in Thailand and Malaysia

BACKGROUND

Linkage studies have reported high rates of previously unascertained mortality among people living with HIV (PLHIV) who have been lost to follow-up (LTFU). We assessed survival outcomes among PLHIV who were LTFU in Thailand and Malaysia, through linkages to a national death registry or HIV database.

METHODS

Data linkages with the national death registry or national HIV database were conducted in 2020 on all PLHIV who met LTFU criteria while enrolled in care at participating HIV clinical sites. LTFU was defined as having no documented clinical contact in the previous year, excluding transfers and deaths. Survival time was analyzed using the Cox regression, stratified by site.

RESULTS

Data linkages were performed for 489 PLHIV who had been LTFU at sites in Malaysia (n = 2) and Thailand (n = 4). There were 151 (31%) deaths after being LTFU; the mortality rate was 4.89 per 100 person-years. Risk factors for mortality after being LTFU were older age [41-50 years: hazard ratio (HR) = 1.99, 95% confidence interval (CI): 1.08 to 3.68; and older than 50 years: HR = 4.93, 95% CI: 2.63 to 9.22; vs. age 30 years or younger]; receiving NRTI + PI (HR = 1.87, 95% CI: 1.22 to 2.85 vs. NRTI + NNRTI); positive hepatitis C antibody (HR = 2.25, 95% CI: 1.40 to 3.62); and having previous AIDS illness (HR = 1.45, 95% CI: 1.03 to 2.05). An improved survival was seen with a higher CD4 count (CD4 351-500 cells/µL: HR = 0.40, 95%CI: 0.21-0.76; and CD4 >500 cells/µL: HR = 0.43, 95%CI: 0.25-0.75; vs. CD4 ≤200 cells/µL).

CONCLUSIONS

Almost one-third of PLHIV who were LTFU in this cohort had died while out of care, emphasizing the importance of efforts to reengage PLHIV after they have been LTFU and ensure they have access to ongoing ART.

Trends in Follow-Up Visits Among People Living With HIV: Results From the TREAT Asia and Australian HIV Observational Databases

BACKGROUND

Less frequent follow-up visits may reduce the burden on people living with HIV (PLHIV) and health care facilities. We aimed to assess trends in follow-up visits and survival outcomes among PLHIV in Asia and Australasia.

SETTINGS

PLHIV enrolled in TREAT Asia HIV Observational Database (TAHOD) or Australian HIV Observational Database (AHOD) from 2008 to 2017 were included.

METHODS

Follow-up visits included laboratory testing and clinic visit dates. Visit rates and survival were analyzed using repeated measure Poisson regression and competing risk regression, respectively. Additional analyses were limited to stable PLHIV with viral load <1000 copies/mL and self-reported adherence ≥95%.

RESULTS

We included 7707 PLHIV from TAHOD and 3289 PLHIV from AHOD. Visit rates were 4.33 per person-years (/PYS) in TAHOD and 3.68/PYS in AHOD. Both TAHOD and AHOD showed decreasing visit rates in later calendar years compared with that in years 2008-2009 (P < 0.001 for both cohorts). Compared with PLHIV with 2 visits, those with ≥4 visits had poorer survival: TAHOD ≥4 visits, subhazard ratio (SHR) = 1.88, 95% confidence interval (CI): 1.16 to 3.03, P = 0.010; AHOD ≥4 visits, SHR = 1.80, 95% CI: 1.10 to 2.97, P = 0.020; whereas those with ≤1 visit showed no differences in mortality. The association remained evident among stable PLHIV: TAHOD ≥4 visits, SHR = 5.79, 95% CI: 1.84 to 18.24, P = 0.003; AHOD ≥4 visits, SHR = 2.15, 95% CI: 1.20 to 3.85, P = 0.010, compared with 2 visits.

CONCLUSIONS

Both TAHOD and AHOD visit rates have declined. Less frequent visits did not affect survival outcomes; however, poorer health possibly leads to increased follow-up and higher mortality. Reducing visit frequency may be achievable among PLHIV with no other medical complications.

Loss to follow-up and associated factors of patients in the National AIDS Program in Thailand

BACKGROUND

Loss to follow-up (LTFU) is a crucial indicator to evaluate the effectiveness of HIV care and treatment programmes. We assessed the LTFU rate and associated factors of Thai HIV-infected patients who enrolled in the National AIDS Program (NAP) for two periods: prior to (pre-ART) and after starting ART (ART-patients).

METHODS

Thai HIV patients aged ≥15 years enrolled in NAP from 2008 to 2014. Vital status was ascertained by linkage with the National Death Registry. Competing risk models were used to calculate the adjusted sub-distribution hazards (aSHR) for LTFU for pre-ART and ART-patients, with death considered as a competing risk.

RESULTS

A total of 157,026 patients registered in care and were included in analyses. The cumulative incidence of LTFU in pre-ART patients at 1 year was 10.2%, whereas in ART-patients it was 12.8%. Among pre-ART patients, younger age (<30 versus ≥45 years, aSHR 1.60, 95% CI 1.49, 1.72), less advanced HIV stage (aSHR 1.29, 95% CI 1.21, 1.37) and higher CD4⁺ T-cell count (≥350 versus <100, aSHR 6.31, 95% CI 5.74, 6.95) had a higher chance of LTFU. ART-patients with high baseline CD4⁺ T-cell count (CD4 ≥350 versus CD4 <50, aSHR 2.06, 95% CI 1.97, 2.15) and non-advanced HIV stage had increased risk of LTFU.

CONCLUSIONS

Our findings provide new evidence of the LTFU rate in Thai HIV-infected patients in NAP. Emphasis needs to be placed on improving follow-up in all patients with higher CD4⁺ T-cell counts. LTFU will be important to monitor as programmes move to commence ART regardless of CD4⁺ T-cell count.

Human immunodeficiency virus-infected young people in Australia: data from the Australian HIV Observational Database

BACKGROUND

Individuals aged 13-24 years undergo vast physical, cognitive, social and psychological changes. Australian data regarding clinical outcomes of those diagnosed with HIV in this age are sparse.

AIM

We aimed to describe demographic factors, virologic and clinical outcomes of individuals aged 13-24 years diagnosed with human immunodeficiency virus (HIV).

METHODS

Patients diagnosed with HIV after 1997 in the Australian HIV Observational Database were divided into young adults, diagnosed at age <25 years (n = 223), and older adults (n = 1957). Demographic and clinical factors were compared between groups.

RESULTS

Young adults had a median age at diagnosis of 22 years (inter quartile range (IQR) 20-24) and median age at treatment initiation of 24 years (IQR 22-26). They were more likely to be female than the older cohort (21.1 vs 10.8%; P < 0.001). Men who have sex with men was the most common exposure category in both groups. CD4 count at diagnosis was significantly higher in younger than older adults (median 460 vs 400 cells/mm³ , P = 0.006), whereas HIV viral load at diagnosis was lower (35 400 vs 61 659 copies/mL, P = 0.011). The rate of loss to follow up (LTFU) was higher in young adults (8.0 vs 4.3 per 100PY, P < 0.001). Young adults were more likely to have a treatment interruption compared to older adults (5.3 vs 4.0 per 100PY, P = 0.039). Rates of treatment switch, time to treatment change, and CD4 and viral load responses to treatment were similar between groups.

CONCLUSIONS

Young adults were diagnosed with HIV at higher CD4 counts and lower viral loads than their older counterparts. LTFU and treatment interruption were more common highlighting the need for extra efforts directed towards retention in care and education regarding the risks of treatment interruptions.

Long-term loss to follow-up in the TREAT Asia HIV Observational Database (TAHOD)

OBJECTIVES

With earlier antiretroviral therapy (ART) initiation, time spent in HIV care is expected to increase. We aimed to investigate loss to follow-up (LTFU) in Asian patients who remained in care 5 years after ART initiation.

METHODS

Long-term LTFU was defined as LTFU occurring after 5 years on ART. LTFU was defined as (1) patients not seen in the previous 12 months; and (2) patients not seen in the previous 6 months. Factors associated with LTFU were analysed using competing risk regression.

RESULTS

Under the 12-month definition, the LTFU rate was 2.0 per 100 person-years (PY) [95% confidence interval (CI) 1.8-2.2 among 4889 patients included in the study. LTFU was associated with age > 50 years [sub-hazard ratio (SHR) 1.64; 95% CI 1.17-2.31] compared with 31-40 years, viral load ≥ 1000 copies/mL (SHR 1.86; 95% CI 1.16-2.97) compared with viral load < 1000 copies/mL, and hepatitis C coinfection (SHR 1.48; 95% CI 1.06-2.05). LTFU was less likely to occur in females, in individuals with higher CD4 counts, in those with self-reported adherence ≥ 95%, and in those living in high-income countries. The 6-month LTFU definition produced an incidence rate of 3.2 per 100 PY (95% CI 2.9-3.4 and had similar associations but with greater risks of LTFU for ART initiation in later years (2006-2009: SHR 2.38; 95% CI 1.93-2.94; and 2010-2011: SHR 4.26; 95% CI 3.17-5.73) compared with 2003-2005.

CONCLUSIONS

The long-term LTFU rate in our cohort was low, with older age being associated with LTFU. The increased risk of LTFU with later years of ART initiation in the 6-month analysis, but not the 12-month analysis, implies that there was a possible move towards longer HIV clinic scheduling in Asia.

Trends in mortality among ART-treated HIV-infected adults in the Asia-Pacific region between 1999 and 2017: results from the TREAT Asia HIV Observational Database (TAHOD) and Australian HIV Observational Database (AHOD) of IeDEA Asia-Pacific

INTRODUCTION

AIDS-related deaths in people living with HIV/AIDS have been decreasing in number since the introduction of combination antiretroviral treatment (cART). However, data on recent causes of death in the Asia-Pacific region are limited. Hence, we analysed and compared AIDS-related and non-AIDS-related mortality in high- and low-income settings in the region.

METHODS

Patients from the TREAT Asia HIV Observational Database (TAHOD) and Australian HIV Observational Database (AHOD) receiving cART between 1999 and 2017 were included. Causes of death verification were based on review of the standardized Cause of Death (CoDe) form designed by the D:A:D group. Cohorts were grouped as AHOD (all high-income sites), TAHOD-high (high/upper-middle income countries) and TAHOD-low (lower-middle income countries). TAHOD sites were split into high/upper-middle income and lower-middle income country settings based on World Bank classifications. Competing risk regression was used to analyse factors associated with AIDS and non-AIDS-related mortality.

RESULTS

Of 10,386 patients, 522 died; 187 from AIDS-related and 335 from non-AIDS-related causes. The overall incidence rate of deaths during follow-up was 0.28 per 100 person-years (/100 PYS) for AIDS and 0.51/100 PYS for non-AIDS. Analysis indicated that the incidence rate of non-AIDS mortality decreased from 0.78/100 PYS to 0.37/100 PYS from year groups 2003 to 2007 to 2013 to 2017 (p < 0.001). Similarly, incidence rates of AIDS-related deaths decreased from 0.51/100 PYS to 0.09/100 PYS from year groups 2003 to 2007 to 2013 to 2017 (p < 0.001). More recent years of follow-up were associated with reduced hazard for non-AIDS mortality (2008 to 2012: aSHR (adjusted sub-hazard ratio) 0.72, 95% confidence interval (CI) 0.54 to 0.96, p = 0.027; 2013 to 2017: aSHR 0.64, 95% CI 0.47 to 0.87, p = 0.004) compared to years 2003 to 2007. The AHOD cohort had almost twice the hazard of non-AIDS mortality compared to TAHOD-low (lower-middle income sites) (aSHR 1.72, 95% CI, 1.20 to 2.46, p = 0.003); there were no differences between cohorts for AIDS-related mortality (p = 0.834).

CONCLUSION

AIDS and non-AIDS-related mortality rates have decreased over the past years in the Asia-Pacific region. There is a greater risk for non-AIDS-associated deaths in the AHOD cohort compared to lower-middle income settings in TAHOD.

Lost but not forgotten: A population-based study of mortality and care trajectories among people living with HIV who are lost to follow-up in Ontario, Canada

Objectives

Selection as a consequence of volunteer participation in, and loss to follow‐up from, cohort studies may bias estimates of mortality and other health outcomes. To quantify this potential, we estimated mortality and health service use among people living with HIV (PLWH) who were lost to cohort follow‐up (LTCFU) from a volunteer clinical HIV‐infected cohort, and compared these to mortality and health service use in active cohort participants and non‐cohort‐participants living with HIV in Ontario, Canada.

Methods

We analysed population‐based provincial health databases from 1995 to 2014, identifying PLWH ≥ 18 years old; these included data from participants in the Ontario HIV Treatment Network Cohort Study (OCS), a volunteer, multi‐site clinical HIV‐infected cohort. We calculated all‐cause mortality, hospitalization and emergency department (ED) visit rates per 100 person‐years (PY) and estimated hazard ratios (HRs) of mortality, adjusting for age, sex, income, rurality, and immigration status.

Results

Among 23 043 PLWH, 5568 were OCS participants. Compared with nonparticipants, participants were younger and less likely to be female, to be an immigrant and to reside in a major urban centre, and had lower comorbidity. Mortality among active participants, participants LTCFU and nonparticipants was 2.52, 3.30 and 2.20 per 100 PY, respectively. After adjustment for covariates, mortality risk was elevated among participants LTCFU compared with active participants (HR 2.26; 95% confidence interval 1.91, 2.68). Age‐adjusted hospitalization rates and ED visit rates were highest among participants LTCFU.

Conclusions

Mortality risk and use of health care resources were lower among active cohort participants. Our findings may inform health outcome estimates based on volunteer cohorts, as well as quantitative bias adjustment to correct for such biases.

Early suboptimal ART adherence was associated with missed clinical visits in HIV-infected patients in Asia

Missed clinic visits can lead to poorer treatment outcomes in HIV-infected patients. Suboptimal antiretroviral therapy (ART) adherence has been linked to subsequent missed visits. Knowing the determinants of missed visits in Asian patients will allow for appropriate counselling and intervention strategies to ensure continuous engagement in care. A missed visit was defined as having no assessments within six months. Repeated measures logistic regression was used to analyse factors associated with missed visits. A total of 7100 patients were included from 12 countries in Asia with 2676 (37.7%) having at least one missed visit. Patients with early suboptimal self-reported adherence <95% were more likely to have a missed visit compared to those with adherence ≥95% (OR = 2.55, 95% CI(1.81-3.61)). Other factors associated with having a missed visit were homosexual (OR = 1.45, 95%CI(1.27-1.66)) and other modes of HIV exposure (OR = 1.48, 95%CI(1.27-1.74)) compared to heterosexual exposure; using PI-based (OR = 1.33, 95%CI(1.15-1.53) and other ART combinations (OR = 1.79, 95%CI(1.39-2.32)) compared to NRTI+NNRTI combinations; and being hepatitis C co-infected (OR = 1.27, 95%CI(1.06-1.52)). Patients aged >30 years (31-40 years OR = 0.81, 95%CI(0.73-0.89); 41-50 years OR = 0.73, 95%CI(0.64-0.83); and >50 years OR = 0.77, 95%CI(0.64-0.93)); female sex (OR = 0.81, 95%CI(0.72-0.90)); and being from upper middle (OR = 0.78, 95%CI(0.70-0.80)) or high-income countries (OR = 0.42, 95%CI(0.35-0.51)), were less likely to have missed visits. Almost 40% of our patients had a missed clinic visit. Early ART adherence was an indicator of subsequent clinic visits. Intensive counselling and adherence support should be provided at ART initiation in order to optimise long-term clinic attendance and maximise treatment outcomes.

HIV Viral Load Suppression in Adults and Children Receiving Antiretroviral Therapy-Results From the IeDEA Collaboration

BACKGROUND

Having 90% of patients on antiretroviral therapy (ART) and achieving an undetectable viral load (VL) is 1 of the 90:90:90 by 2020 targets. In this global analysis, we investigated the proportions of adult and paediatric patients with VL suppression in the first 3 years after ART initiation.

METHODS

Patients from the IeDEA cohorts who initiated ART between 2010 and 2014 were included. Proportions with VL suppression (<1000 copies/mL) were estimated using (1) strict intention to treat (ITT)-loss to follow-up (LTFU) and dead patients counted as having detectable VL; and (2) modified ITT-LTFU and dead patients were excluded. Logistic regression was used to identify predictors of viral suppression at 1 year after ART initiation using modified ITT.

RESULTS

A total of 35,561 adults from 38 sites/16 countries and 2601 children from 18 sites/6 countries were included. When comparing strict with modified ITT methods, the proportion achieving VL suppression at 3 years from ART initiation changed from 45.1% to 90.2% in adults, and 60.6% to 80.4% in children. In adults, older age, higher CD4 count pre-ART, and homosexual/bisexual HIV exposure were associated with VL suppression. In children, older age and higher CD4 percentage pre-ART showed significant associations with VL suppression.

CONCLUSIONS

Large increases in the proportion of VL suppression in adults were observed when we excluded those who were LTFU or had died. The increases were less pronounced in children. Greater emphasis should be made to minimize LTFU and maximize patient retention in HIV-infected patients of all age groups.

A pseudo-random patient sampling method evaluated

OBJECTIVES

To compare two human immunodeficiency virus (HIV) cohorts to determine whether a pseudo-random sample can represent the entire study population.

STUDY DESIGN AND SETTING

HIV-positive patients receiving care at eight sites in seven Asian countries. The TREAT Asia HIV Observational database (TAHOD) pseudo-randomly selected a patient sample, while TREAT Asia HIV Observational database-Low Intensity Transfer (TAHOD-LITE) included all patients. We compared patient demographics, CD4 count, and HIV viral load testing for each cohort. Risk factors associated with CD4 count response, HIV viral load suppression (<400 copies/mL), and survival were determined for each cohort.

RESULTS

There were 2,318 TAHOD patients and 14,714 TAHOD-LITE patients. Patient demographics, CD4 count, and HIV viral load testing rates were broadly similar between the cohorts. CD4 count response and all-cause mortality were consistent among the cohorts with similar risk factors. HIV viral load response appeared to be superior in TAHOD and many risk factors differed, possibly due to viral load being tested on a subset of patients.

CONCLUSION

Our study gives the first empirical evidence that analysis of risk factors for completely ascertained end points from our pseudo-randomly selected patient sample may be generalized to our larger, complete population of HIV-positive patients. However, results can significantly vary when analyzing smaller or pseudo-random samples, particularly if some patient data are not completely missing at random, such as viral load results.

A Decade of Combination Antiretroviral Treatment in Asia: The TREAT Asia HIV Observational Database Cohort

Asian countries have seen the expansion of combination antiretroviral therapy (cART) over the past decade. The TREAT Asia HIV Observational Database (TAHOD) was established in 2003 comprising 23 urban referral sites in 13 countries across the region. We examined trends in treatment outcomes in patients who initiated cART between 2003 and 2013. Time of cART initiation was grouped into three periods: 2003-2005, 2006-2009, and 2010-2013. We analyzed trends in undetectable viral load (VL; defined as VL <400 copies/ml), CD4 changes from pre-cART levels, and overall survival. Of 6,521 patients included, the overall median CD4 count at cART initiation was 120 cells/μl (interquartile range: 38-218). Despite an increase over time, pre-cART CD4 counts remained <200 cells/μl. Adjusted analyses showed undetectable VL was more likely when starting cART in later years [2006-2009: odds ratio (OR) = 1.76, 95% confidence interval (CI) (1.45, 2.15); and 2010-2013: OR = 3.04, 95% CI (2.33, 3.97), all p < .001, compared to 2003-2005], and survival was improved [2006-2009: subdistribution hazard ratio (SHR) = 0.41, 95% CI (0.27, 0.61), 2010-2013: SHR = 0.29, 95% CI (0.17, 0.49), all p < .001, compared to 2003-2005]. No differences in CD4 response was observed over time. Age and CD4 levels prior to cART initiation were associated with all three treatment outcomes, with older age and higher CD4 counts being associated with undetectable VL. Survival and VL response on cART have improved over the past decade in TAHOD, although CD4 count at cART initiation remained low. Greater effort should be made to facilitate earlier HIV diagnosis and linkage to care and treatment, to achieve greater improvements in treatment outcomes.

Treatment durability and virological response in treatment-experienced HIV-positive patients on an integrase inhibitor-based regimen: an Australian cohort study

Background: Integrase inhibitors (INSTI) are a newer class of antiretroviral (ARV) drugs that offer additional treatment options for experienced patients. Our aim is to describe treatment durability and virological outcomes in treatment-experienced HIV-positive patients using INSTI-based regimens. Methods: All patients in the Australian HIV Observational Database who had received an INSTI-based regimen ≥ 14 days as well as previous therapy were included in the study. We defined two groups of treatment-experienced patients: (1) those starting a second-line regimen with INSTI; and (2) highly experienced patients, defined as having prior exposure to all three main ARV classes, nucleoside reverse transcriptase inhibitor, nonnucleoside reverse transcriptase inhibitors and protease inhibitors, before commencing INSTI. Survival methods were used to determine time to viral suppression and treatment switch, stratified by patient treatment experience. Covariates of interest included age, gender, hepatitis B and C co-infection, previous antiretroviral treatment time, patient treatment experience and baseline viral load. Results: Time to viral suppression and regimen switching from INSTI initiation was similar for second-line and highly experienced patients. The probability of achieving viral suppression at 6 months was 77.7% for second-line patients and 68.4% for highly experienced patients. There were 60 occurrences of regimen switching away from INSTI observed over 1274.0 person-years, a crude rate of 4.71 (95% CI: 3.66-6.07) per 100 person-years. Patient treatment experience was not a significant factor for regimen switch according to multivariate analysis, adjusting for relevant covariates. Conclusions: We found that INSTI-based regimens were potent and durable in experienced HIV-positive patients receiving treatment outside clinical trials. These results confirm that INSTI-based regimens are a robust treatment option.

Antiretroviral treatment use, co-morbidities and clinical outcomes among Aboriginal participants in the Australian HIV Observational Database (AHOD)

Background

There are few data regarding clinical care and outcomes of Indigenous Australians living with HIV and it is unknown if these differ from non-Indigenous HIV-positive Australians.

Methods

AHOD commenced enrolment in 1999 and is a prospective cohort of HIV-positive participants attending HIV outpatient services throughout Australia, of which 20 (74 %) sites report Indigenous status. Data were collected up until March 2013 and compared between Indigenous and non-Indigenous participants. Person-year methods were used to compare death rates, rates of loss to follow-up and rates of laboratory testing during follow-up between Indigenous and non-Indigenous participants. Factors associated with time to first combination antiretroviral therapy (cART) regimen change were assessed using Kaplan Meier and Cox Proportional hazards methods.

Results

Forty-two of 2197 (1.9 %) participants were Indigenous. Follow-up amongst Indigenous and non-Indigenous participants was 332 & 16270 person-years, respectively. HIV virological suppression was achieved in similar proportions of Indigenous and non-Indigenous participants 2 years after initiation of cART (81.0 % vs 76.5 %, p = 0.635). Indigenous status was not independently associated with shorter time to change from first- to second-line cART (aHR 0.95, 95 % CI 0.51-1.76, p = 0.957). Compared with non-Indigenous participants, Indigenous participants had significantly less frequent laboratory monitoring of CD4 count (rate:2.76 tests/year vs 2.97 tests/year, p = 0.025) and HIV viral load (rate:2.53 tests/year vs 2.93 tests/year, p < 0.001), while testing rates for lipids and blood glucose were almost half that of non-indigenous participants (rate:0.43/year vs 0.71 tests/year, p < 0.001). Loss to follow-up (23.8 % vs 29.8 %, p = 0.496) and death (2.4 % vs 7.1 %, p = 0.361) occurred in similar proportions of indigenous and non-Indigenous participants, respectively, although causes of death in both groups were mostly non-HIV-related.

Conclusions

As far as we are aware, these are the first data comparing clinical outcomes between Indigenous and non-Indigenous HIV-positive Australians. The forty-two Indigenous participants represent over 10 % of all Indigenous Australians ever diagnosed with HIV. Although outcomes were not significantly different, Indigenous patients had lower rates of laboratory testing for HIV and lipid/glucose parameters. Given the elevated risk of cardiovascular disease in the general Indigenous community, the additional risk factor of HIV infection warrants further focus on modifiable risk factors to maximise life expectancy in this population.