Estimands in practice: Bridging the gap between study objectives and statistical analysis

The International Council for Harmonisation (ICH) guideline E9 Statistical Principles for Clinical Trials (1) was issued in 1998. In October 2014, an addendum to ICH E9 was proposed on statistical principles relating to estimands and sensitivity analyses. The final version of the addendum to ICH E9 (R1) (2) was issued in November 2019. This virtual edition of Pharmaceutical Statistics takes a closer look at some of the progress that has been made since 2018 when implementing the estimand framework within clinical research. The articles discussed in this virtual issue are not new, but a compilation from previous issues. This specific article will act as a refresher for those not familiar with the topic and discuss the ABCs of estimands and their proposed deployment for improving the quality of clinical research. An overview of the more recent Pharmaceutical Statistics articles on estimands will be provided, signifying areas where progress have been made. The articles should be considered as contributions to the ongoing discussions rather than the final word. Finally, a personal perspective on the estimand success story and remaining challenges with proposed solutions will be discussed.

UK military women: mental health, military service and occupational adjustment

Background

Recently, the UK Armed Forces have revised the ground close combat role to include women.

Aims

To assess the potential mental health impact of this initiative we examined gender differences in deployment patterns, work strain, occupational factors, mental health, alcohol use and help-seeking following operational deployment.

Methods

The study was a secondary analysis of self-report survey data; 8799 men (88%) and 1185 women (12%) provided data. A sub-sample (47%, n = 4659) provided data concerning post-deployment help-seeking. The latter consisted of 408 women (8.8%) and 4251 men (91%).

Results

With the exception of alcohol misuse, which was significantly lower for women, women reported significantly more common mental disorder symptoms, subjective depression and self-harm. Women were significantly more likely to seek help from healthcare providers. Men were significantly more likely to have deployed operationally and for longer cumulative periods. Subjective work strain, but not job control, was significantly lower for women whose military careers were significantly shorter. Post-traumatic stress disorder (PTSD) symptom intensity was similar to men.

Conclusions

With the exception of PTSD and alcohol misuse, UK military women experience more mental health-related problems than military men. This finding was not related to the more arduous aspects of military service as women served for shorter times, deployed less and for shorter cumulative periods and were less likely to report work-related stress.

Exploring professional issues: the psychosocial component of genetic counseling in genomic healthcare

Aim: To determine UK genetic counselors’ (UKGCs) opinion regarding ‘the psychosocial component of the UKGC remit in the new genomics era’. Methods: Facilitated discussions at a national conference (2016) using interactive methodologies (58 participants). Results: UKGCs recognized the rapid rate of change emerging with advances in genomic science. Change will be required to the UKGC remit and the roles, rules, relationships and responsibilities that underpin it (29 topics identified). UKGCs supported their ‘unique selling point’; integrating knowledge and the explicit focus on psychosocial aspects of genomic healthcare. By 2019, some of the aspirations have been achieved. Conclusion: UKGCs should proactively position themselves to capitalize on the challenges and opportunities of genomic healthcare to maximize patient benefit.

British military women: combat exposure, deployment and mental health

BACKGROUND

Internationally, women are about to undertake combat duties alongside their male colleagues. The psychological effect of this policy change is largely unknown.

AIMS

To explore the mental health impact of combat exposure among military women.

METHODS

Self-report, between-subjects survey data were collected in Iraq and Afghanistan on four occasions between 2009 and 2014 (n = 4139). Differences in mental health, stigmatization, deployment experiences, intimate relationship impact, perception of family support levels, unit cohesion, leadership and help-seeking were compared between deployed men and women. Comparisons were repeated with the study sample stratified by level of combat exposure. Outcomes were examined using logistic regression adjusted for socio-demographic, mental health and military factors.

RESULTS

Overall, 4.1% of women and 4.3% of men reported post-traumatic stress disorder (PTSD) (odds ratio (OR) 1.31, 95% confidence interval (95% CI) 0.70-2.46); 22% of women and 16% of men reported symptoms of common mental disorder (CMD) (OR 1.52, 95% CI 1.11-2.08). Women were less likely to report mental health-related stigmatization (OR 0.68, 95% CI 0.53-0.87), negative relationship impact from deployment (OR 0.69, 95% CI 0.49-0.98) and subjective unit cohesion (OR 0.69, 95% CI 0.53-0.90). Help-seeking for emotional problems was similar by gender (OR 1.22, 95% CI 0.84-1.77). Overall, outcomes were minimally impacted by level of combat exposure.

CONCLUSIONS

Although women experienced more CMD symptoms, PTSD symptoms were similar by gender. Subject to confirmation of the study findings, women may not require enhanced mental healthcare during deployment for exposure-based conditions such as PTSD when undertaking the ground close combat role.

The EuroSIDA study: 25 years of scientific achievements

The EuroSIDA study was initiated in 1994 and follows adult people living with HIV (PLHIV) in 100 collaborating clinics across 35 countries covering all European regions, Israel and Argentina. The study aims to study the long-term virological, immunological and clinical outcomes of PLHIV and to monitor temporal changes and regional differences in outcomes across Europe. Annually collected data include basic demographic characteristics, information on AIDS- and non-AIDS-related clinical events, and details about antiretroviral therapy (ART), hepatitis C treatment and other medications, in addition to a range of laboratory values. The summer 2016 data set held data from a total of 23 071 individuals contributing 174 481 person-years of follow-up, while EuroSIDA's unique plasma repository held over 160 000 samples. Over the past 25 years, close to 300 articles have been published in peer-reviewed journals (h-index 52), covering a range of scientific focus areas, including monitoring of clinical and virological outcomes, ART uptake, efficacy and adverse events, the influence of hepatitis virus coinfection, variation in the quality of HIV care and management across settings and regions, and biomarker research. Recognizing that there remain unresolved issues in the clinical care and management of PLHIV in Europe, EuroSIDA was one of the cohorts to found The International Cohort Consortium of Infectious Disease (RESPOND) cohort consortium on infectious diseases in 2017. In celebration of the EuroSIDA study's 25th anniversary, this article aims to summarize key scientific findings and outline current and future scientific focus areas.

Parent use of complementary medicine remedies and services for the management of respiratory tract infection in children: a qualitative study

BACKGROUND

The use of complementary and alternative medicine (CAM) is increasing globally, in both adults and children. A common condition where CAM is used in children is acute respiratory tract infection (ARTI). However, limited information exists regarding specific CAM modalities used in children, and the factors that influence a parent's decision to use CAM for ARTI in children. This research aimed to address this knowledge gap.

METHOD

This research used a qualitative descriptive approach. Parents residing in Greater Melbourne, Australia, who had children aged from 0-12 years, and had used CAM for treating ARTI in their children in the last 12 months, were eligible to participate. Parents' perspectives were captured using individual semi-structured interviews, which were then transcribed verbatim. Data were analysed using content analysis.

RESULTS

Twenty-four families were interviewed. Several strategies to improve trustworthiness were implemented. Three themes underpinning the parents' decision to use CAM emerged from the data: safety, internal drivers and external drivers. Parents used a breadth of different treatments, predominantly food as medicine, followed by aromatherapy and other CAM remedies typically found in the kitchen, to manage ARTI in their children. Parents often used both CAM practitioners and mainstream medicine to manage ARTI in their children. While mainstream medicine was typically used to rule out any sinister pathology, CAM was often used as a frontline treatment option, with food as medicine (e.g. soups) dominating. This was due in part to concerns regarding the negative aspects of pharmaceutical use. Parents utilised a diverse range of information sources to inform their decision-making, including friends, families and the internet; traditional sources of research evidence were generally not used.

CONCLUSION

Child safety was a major factor influencing a primary carer's decision to utilise CAM for ARTI. The safety and effectiveness of remedies utilised by parents now warrants further investigation.

Occupational stress in Remotely Piloted Aircraft System operators

BACKGROUND

Although there is currently little research data to support the contention, concerns have been raised about possible traumatic stressors inherent to Remotely Piloted Aircraft System (RPAS) operator roles. Factors such as exposure to visually traumatic events compounded by long working hours and blurred boundaries between military and civilian life have been cited as potential stressors. Robust research into the well-being of RPAS operators is scarce and mostly samples US personnel.

AIMS

To provide mental health and well-being data relating to UK RPAS operators.

METHODS

UK RPAS operators completed mental health questionnaires to assess levels of post-traumatic stress disorder (PTSD), anxiety and depression symptoms, alcohol use and occupational functioning. Respondents were also asked about work patterns.

RESULTS

Forty-one per cent of the sample reported potentially hazardous alcohol use. Ten per cent met psychiatric symptom criteria for moderate or severe anxiety, and 20% for moderate depressive symptoms. While there were no cases of probable PTSD, 30% of the sample reported sub-clinical PTSD symptoms likely to impair occupational functioning. Overall, 70% of the sample reported that psychological symptoms significantly impaired their functioning.

CONCLUSIONS

Compared to UK military sub-groups, RPAS operators were not at increased risk of mental health problems. However, a high proportion of the sample reported significant functional impairment, which has not been explored in other comparable studies. The most frequently highlighted work-related stressors were timing of RPAS work and operator shift patterns.

The NICE classification for 'Ultra-radical (extensive) surgery for advanced ovarian cancer' guidance does not meaningfully predict postoperative complications: a cohort study

OBJECTIVE

To determine which descriptors of cytoreductive surgical extent in advanced ovarian cancer (AOC) best predict postoperative morbidity.

DESIGN

Retrospective notes review.

SETTING

A gynaecological cancer centre in the UK.

POPULATION

Six hundred and eight women operated on for AOC over a period of 114 months at a tertiary cancer centre, between 16 August 2007 and 16 February 2017.

METHODS

Outcome data were analysed by six approaches to classify the extent of surgery: standard/ultra-radical surgery; standard/radical/supra-radical surgery; presence/absence of gastrointestinal resections; low/intermediate/high surgical complexity score (SCS); presence of bowel anastomoses and/or diaphragmatic surgery; and the presence/absence of multiple bowel resections.

MAIN OUTCOME MEASURES

Major (grades 3-5) postoperative morbidity and mortality.

RESULTS

Forty-three (7.1%) patients experienced major complications. Grade-5 complications occurred in six patients (1.0%). Patients who underwent multiple bowel resections had a relative risk (RR) of 7.73 (95% confidence interval, 95% CI 3.92-15.26), patients with a high SCS had an RR of 6.12 (95% CI 3.25-11.52), patients with diaphragmatic surgery and gastrointestinal anastomosis had an RR of 5.57 (95% CI 2.65-11.72), patients with 'any gastrointestinal resection' had an RR of 4.69 (95% CI 2.66-8.24), patients with ultra-radical surgery had an RR of 4.65 (95% CI 2.26-8.79), and patients with supra-radical surgery had an RR of 4.20 (95% CI 2.35-7.51) of grades 3-5 morbidity, compared with patients undergoing standard surgery as defined by the National Institute for Health and Care Excellence (NICE) in the UK. No significant difference was seen in the rate of major morbidity between standard (6/59, 10.2%) and ultra-radical (9/81, 11.1%) surgery within the cohort who had intermediate complex surgery (P > 0.05).

CONCLUSIONS

The numbers of procedures performed significantly correlate with major morbidity. The number of procedures performed better predicted major postoperative morbidity than the performance of certain 'high risk' procedures. We recommend using SCS to define a higher risk operation. NICE should re-evaluate the use of the term 'ultra-radical' surgery.

TWEETABLE ABSTRACT

Multiple bowel resection is the best predictor of morbidity and is more predictive than 'ultra-radical surgery'.

Systematic review with meta-analysis: online psychological interventions for mental and physical health outcomes in gastrointestinal disorders including irritable bowel syndrome and inflammatory bowel disease

BACKGROUND

Online psychotherapy has been successfully used as supportive treatment in many chronic illnesses. However, there is a lack of evidence on its role in the management of gastrointestinal (GI) diseases.

AIMS

To examine whether online psychological interventions improve mental and physical outcomes in gastrointestinal diseases.

METHODS

We searched CINAHL Plus, MEDLINE, EMBASE, Health Management Information Consortium, PsycINFO, British Nursing Index, Cochrane Library, a specialised register of the IBD/FBD Cochrane Group, MEDLINE (PubMed) WHO International Clinical Trial Registry, ClinicalTrials.gov, and reference lists of all papers included in the review. The Cochrane Risk of Bias Tool was used to assess internal validity. Where possible, data were pooled using random-effects meta-analysis.

RESULTS

We identified 11 publications (encompassing nine studies) meeting inclusion criteria. One study had a high risk of selection bias (allocation concealment), all studies had a high risk of performance and detection bias. Eight studies were included in the meta-analyses (6 on irritable bowel syndrome [IBS] and two on inflammatory bowel disease [IBD]). Online cognitive behavioural therapy (CBT) was shown to significantly improve gastrointestinal symptom-specific anxiety (MD: -8.51, 95% CI -12.99 to -4.04, P = 0.0002) and lessen symptom-induced disability (MD: -2.78, 95% CI -5.43 to -0.12, P = 0.04) in IBS post intervention. There was no significant effect of online CBT on any other outcomes in IBS. No significant effect of online psychotherapy was demonstrated in IBD.

CONCLUSION

There is insufficient evidence to demonstrate the effectiveness of online CBT to manage mental and physical outcomes in gastrointestinal diseases.

Enhanced case management can be delivered for patients with EVD in Africa: Experience from a UK military Ebola treatment centre in Sierra Leone

BACKGROUND

Limited data exist describing supportive care management, laboratory abnormalities and outcomes in patients with Ebola virus disease (EVD) in West Africa. We report data which constitute the first description of the provision of enhanced EVD case management protocols in a West African setting.

METHODS

Demographic, clinical and laboratory data were collected by retrospective review of clinical and laboratory records of patients with confirmed EVD admitted between 5 November 2014 and 30 June 2015.

RESULTS

A total of 44 EVD patients were admitted (median age 37 years (range 17-63), 32/44 healthcare workers), and excluding those evacuated, the case fatality rate was 49% (95% CI 33%-65%). No pregnant women were admitted. At admission 9/44 had stage 1 disease (fever and constitutional symptoms only), 12/44 had stage 2 disease (presence of diarrhoea and/or vomiting) and 23/44 had stage 3 disease (presence of diarrhoea and/or vomiting with organ failure), with case fatality rates of 11% (95% CI 1%-58%), 27% (95% CI 6%-61%), and 70% (95% CI 47%-87%) respectively (p = 0.009). Haemorrhage occurred in 17/41 (41%) patients. The majority (21/40) of patients had hypokalaemia with hyperkalaemia occurring in 12/40 patients. Acute kidney injury (AKI) occurred in 20/40 patients, with 14/20 (70%, 95% CI 46%-88%) dying, compared to 5/20 (25%, 95% CI 9%-49%) dying who did not have AKI (p = 0.01). Ebola virus (EBOV) PCR cycle threshold value at baseline was mean 20.3 (SD 4.3) in fatal cases and 24.8 (SD 5.5) in survivors (p = 0.007). Mean national early warning score (NEWS) at admission was 5.5 (SD 4.4) in fatal cases and 3.0 (SD 1.9) in survivors (p = 0.02). Central venous catheters were placed in 37/41 patients and intravenous fluid administered to 40/41 patients (median duration of 5 days). Faecal management systems were inserted in 21/41 patients, urinary catheters placed in 27/41 and blood component therapy administered to 20/41 patients.

CONCLUSIONS

EVD is commonly associated life-threatening electrolyte imbalance and organ dysfunction. We believe that the enhanced levels of protocolized care, scale and range of medical interventions we report, offer a blueprint for the future management of EVD in resource-limited settings.

Legislation of direct-to-consumer genetic testing in Europe: a fragmented regulatory landscape

Despite the increasing availability of direct-to-consumer (DTC) genetic testing, it is currently unclear how such services are regulated in Europe, due to the lack of EU or national legislation specifically addressing this issue. In this article, we provide an overview of laws that could potentially impact the regulation of DTC genetic testing in 26 European countries, namely Austria, Belgium, Cyprus, the Czech Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Ireland, Italy, Latvia, Lithuania, Luxembourg, Norway, Poland, Portugal, Romania, Slovakia, Slovenia, Spain, Sweden, the Netherlands and the United Kingdom. Emphasis is placed on provisions relating to medical supervision, genetic counselling and informed consent. Our results indicate that currently there is a wide spectrum of laws regarding genetic testing in Europe. There are countries (e.g. France and Germany) which essentially ban DTC genetic testing, while in others (e.g. Luxembourg and Poland) DTC genetic testing may only be restricted by general laws, usually regarding health care services and patients' rights.

Surgical management of a cat with hepatic arterioportal fistula

A 9-month-old domestic short-haired cat presented with stunted growth and chronic gastrointestinal signs. Tachypnoea, a heart murmur and cranial abdominal bruit were detected on physical examination. Echocardiography revealed volume overload in all heart chambers. CT angiography identified an abnormal communication between the hepatic arterial circulation and the portal vein, along with multiple acquired shunts. The abnormal vascular communication was surgically ligated. Echocardiography documented improvement in cardiac parameters following surgery and the cat continues to have no clinical signs 39 months after surgery. This report describes successful surgical management of feline hepatic arterioportal fistula for the first time.

Effect of Dialyser Composition and Reuse on Neutrophil Count and Elastase α-1 Proteinase Inhibitor Complex Formation

To assess the inter-relationship of leucopenia and PMN elastase release we undertook a prospective crossover study of 6 patients dialysed with new and reused cuprophane, cellulose acetate and polysulfone membranes. Serial blood samples were analysed for PMN count, and elastase-α 1-proteinase inhibitor complex (Eα1PI) concentrations.

After 15 min dialysis with new membranes median PMN counts fell by 72.2%, 25.3% and 22.1% with cuprophane, cellulose and polysulfone, respectively. With reuse the decreases were reduced to 6.4%, 8% and 13.6%. All membranes produced a gradual increase of Eα1PI. Median Eα1PI accumulation rates (ng ml−1min−1) with new membranes were 175, 169 and 187 for cuprophane, cellulose acetate and polysulfone, respectively. With reuse of cuphro-phane and cellulose acetate these rates fell to 99 and 109 (p<0.05 and p<0.05, respectively), however, with polysulfone it remained unchanged at 180 ng ml−1 min−1. This study highlights differences between two aspects of the neutrophil response to haemodialysis, and demonstrates that extrapolation from individual parameters to conclusions concerning biocompatibility may be inappropriate.

Inhibition of STEP61 ameliorates deficits in mouse and hiPSC-based schizophrenia models

The brain-specific tyrosine phosphatase, STEP (STriatal-Enriched protein tyrosine Phosphatase) is an important regulator of synaptic function. STEP normally opposes synaptic strengthening by increasing N-methyl D-aspartate glutamate receptor (NMDAR) internalization through dephosphorylation of GluN2B and inactivation of the kinases extracellular signal-regulated kinase 1/2 and Fyn. Here we show that STEP₆₁ is elevated in the cortex in the Nrg1^+/- knockout mouse model of schizophrenia (SZ). Genetic reduction or pharmacological inhibition of STEP prevents the loss of NMDARs from synaptic membranes and reverses behavioral deficits in Nrg1^+/- mice. STEP₆₁ protein is also increased in cortical lysates from the central nervous system-specific ErbB2/4 mouse model of SZ, as well as in human induced pluripotent stem cell (hiPSC)-derived forebrain neurons and Ngn2-induced excitatory neurons, from two independent SZ patient cohorts. In these selected SZ models, increased STEP₆₁ protein levels likely reflect reduced ubiquitination and degradation. These convergent findings from mouse and hiPSC SZ models provide evidence for STEP₆₁ dysfunction in SZ.

Long-term effectiveness of recommended boosted protease inhibitor-based antiretroviral therapy in Europe

OBJECTIVES

The aim of the study was to evaluate the long-term response to antiretroviral treatment (ART) based on atazanavir/ritonavir (ATZ/r)-, darunavir/ritonavir (DRV/r)-, and lopinavir/ritonavir (LPV/r)-containing regimens.

METHODS

Data were analysed for 5678 EuroSIDA-enrolled patients starting a DRV/r-, ATZ/r- or LPV/r-containing regimen between 1 January 2000 and 30 June 2013. Separate analyses were performed for the following subgroups of patients: (1) ART-naïve subjects (8%) at ritonavir-boosted protease inhibitor (PI/r) initiation; (2) ART-experienced individuals (44%) initiating the new PI/r with a viral load (VL) ≤500 HIV-1 RNA copies/mL; and (3) ART-experienced patients (48%) initiating the new PI/r with a VL >500 copies/mL. Virological failure (VF) was defined as two consecutive VL measurements >200 copies/mL ≥24 weeks after PI/r initiation. Kaplan-Meier and multivariable Cox models were used to compare risks of failure by PI/r-based regimen. The main analysis was performed with intention-to-treat (ITT) ignoring treatment switches.

RESULTS

The time to VF favoured DRV/r over ATZ/r, and both were superior to LPV/r (log-rank test; P < 0.02) in all analyses. Nevertheless, the risk of VF in ART-naïve patients was similar regardless of the PI/r initiated after controlling for potential confounders. The risk of VF in both treatment-experienced groups was lower for DRV/r than for ATZ/r, which, in turn, was lower than for LPV/r-based ART.

CONCLUSIONS

Although confounding by indication and calendar year cannot be completely ruled out, in ART-experienced subjects the long-term effectiveness of DRV/r-containing regimens appears to be greater than that of ATZ/r and LPV/r.

Sarcopenia is associated with disability status-results from the KORA-Age study

We estimated the prevalence of sarcopenia and its impact on disability in older people. Sarcopenia was found to contribute to higher disability scores. However, our study was not able to show any influence of sarcopenia on the rate of functional decline. This directs attention to an accurate diagnosis of sarcopenia as the onset may be influenced, but its rate may not.

INTRODUCTION

The objectives of this study using data from a population-based cohort were to estimate the prevalence of sarcopenia in older people in Germany and to test the hypothesis that sarcopenia is associated with disability in older adults.

METHODS

Cross-sectional (n = 927) and longitudinal analyses (n = 859) of participants aged ≥65 years at baseline from southern Germany enrolled in the Cooperative Health Research in the Region Augsburg (KORA)-Age study (2009-2012). Sarcopenia was defined based on the European Working Group on Sarcopenia in Older People (EWGSOP) algorithm which includes the presence of both low muscle mass and low muscle function (strength or performance). Disability status was measured by the Health Assessment Questionnaire-Disability Index (HAQ-DI). The presence of disability was defined as HAQ-DI >0. Directed acyclic graphs (DAGs) were constructed to identify potential confounders. The effect of sarcopenia on disability was analyzed using linear mixed effect models with disability values as a continuous outcome.

RESULTS

The overall prevalence of sarcopenia was 5.7% (men 4.0%, women 7.5%) and increased with age. The 3-year incidence of disability was 32.7%. After adjustment for potential confounders, presence of sarcopenia was significantly associated with higher disability scores (0.142 [confidence interval 0.029-0.254]).

CONCLUSION

The prevalence of sarcopenia is consistent with estimates from other European studies using this algorithm. Our results suggest that sarcopenia can contribute to higher disability scores in older adults. However, our study was not able to show any influence of sarcopenia on the rate of functional decline using the EWGSOP diagnostic algorithm for sarcopenia. This directs attention to an accurate diagnosis of sarcopenia as the onset may be influenced, but its rate may not.

Higher rates of triple-class virological failure in perinatally HIV-infected teenagers compared with heterosexually infected young adults in Europe

OBJECTIVES

The aim of the study was to determine the time to, and risk factors for, triple-class virological failure (TCVF) across age groups for children and adolescents with perinatally acquired HIV infection and older adolescents and adults with heterosexually acquired HIV infection.

METHODS

We analysed individual patient data from cohorts in the Collaboration of Observational HIV Epidemiological Research Europe (COHERE). A total of 5972 participants starting antiretroviral therapy (ART) from 1998, aged < 20 years at the start of ART for those with perinatal infection and 15-29 years for those with heterosexual infection, with ART containing at least two nucleoside reverse transcriptase inhibitors (NRTIs) and a nonnucleoside reverse transcriptase inhibitor (NNRTI) or a boosted protease inhibitor (bPI), were followed from ART initiation until the most recent viral load (VL) measurement. Virological failure of a drug was defined as VL > 500 HIV-1 RNA copies/mL despite ≥ 4 months of use. TCVF was defined as cumulative failure of two NRTIs, an NNRTI and a bPI.

RESULTS

The median number of weeks between diagnosis and the start of ART was higher in participants with perinatal HIV infection compared with participants with heterosexually acquired HIV infection overall [17 (interquartile range (IQR) 4-111) vs. 8 (IQR 2-38) weeks, respectively], and highest in perinatally infected participants aged 10-14 years [49 (IQR 9-267) weeks]. The cumulative proportion with TCVF 5 years after starting ART was 9.6% [95% confidence interval (CI) 7.0-12.3%] in participants with perinatally acquired infection and 4.7% (95% CI 3.9-5.5%) in participants with heterosexually acquired infection, and highest in perinatally infected participants aged 10-14 years when starting ART (27.7%; 95% CI 13.2-42.1%). Across all participants, significant predictors of TCVF were those with perinatal HIV aged 10-14 years, African origin, pre-ART AIDS, NNRTI-based initial regimens, higher pre-ART viral load and lower pre-ART CD4.

CONCLUSIONS

The results suggest a beneficial effect of starting ART before adolescence, and starting young people on boosted PIs, to maximize treatment response during this transitional stage of development.