Early Antiretroviral Therapy Not Associated With Higher Cryptococcal Meningitis Mortality in People With Human Immunodeficiency Virus in High-Income Countries: An International Collaborative Cohort Study

BACKGROUND

Randomized controlled trials (RCTs) from low- and middle-income settings suggested that early initiation of antiretroviral therapy (ART) leads to higher mortality rates among people with HIV (PWH) who present with cryptococcal meningitis (CM). There is limited information about the impact of ART timing on mortality rates in similar people in high-income settings.

METHODS

Data on ART-naive PWH with CM diagnosed from 1994 to 2012 from Europe/North America were pooled from the COHERE, NA-ACCORD, and CNICS HIV cohort collaborations. Follow-up was considered to span from the date of CM diagnosis to earliest of the following: death, last follow-up, or 6 months. We used marginal structural models to mimic an RCT comparing the effects of early (within 14 days of CM) and late (14-56 days after CM) ART on all-cause mortality, adjusting for potential confounders.

RESULTS

Of 190 participants identified, 33 (17%) died within 6 months. At CM diagnosis, their median age (interquartile range) was 38 (33-44) years; the median CD4+ T-cell count, 19/μL (10-56/μL); and median HIV viral load, 5.3 (4.9-5.6) log10 copies/mL. Most participants (n = 157 [83%]) were male, and 145 (76%) started ART. Mimicking an RCT, with 190 people in each group, there were 13 deaths among participants with an early ART regimen and 20 deaths among those with a late ART regimen. The crude and adjusted hazard ratios comparing late with early ART were 1.28 (95% confidence interval, .64-2.56) and 1.40 (.66-2.95), respectively.

CONCLUSIONS

We found little evidence that early ART was associated with higher mortality rates among PWH presenting with CM in high-income settings, although confidence intervals were wide.

Multiple imputation strategies for a bounded outcome variable in a competing risks analysis

In patient follow-up studies, events of interest may take place between periodic clinical assessments and so the exact time of onset is not observed. Such events are known as "bounded" or "interval-censored." Methods for handling such events can be categorized as either (i) applying multiple imputation (MI) strategies or (ii) taking a full likelihood-based (LB) approach. We focused on MI strategies, rather than LB methods, because of their flexibility. We evaluated MI strategies for bounded event times in a competing risks analysis, examining the extent to which interval boundaries, features of the data distribution and substantive analysis model are accounted for in the imputation model. Candidate imputation models were predictive mean matching (PMM); log-normal regression with postimputation back-transformation; normal regression with and without restrictions on the imputed values and Delord and Genin's method based on sampling from the cumulative incidence function. We used a simulation study to compare MI methods and one LB method when data were missing at random and missing not at random, also varying the proportion of missing data, and then applied the methods to a hematopoietic stem cell transplantation dataset. We found that cumulative incidence and median event time estimation were sensitive to model misspecification. In a competing risks analysis, we found that it is more important to account for features of the data distribution than to restrict imputed values based on interval boundaries or to ensure compatibility with the substantive analysis by sampling from the cumulative incidence function. We recommend MI by type 1 PMM.

Retrospective cohort study evaluating clinical, biochemical and pharmacological prognostic factors for prostate cancer progression using primary care data

OBJECTIVES

To confirm the association of previously reported prognostic factors with future progression of localised prostate cancer using primary care data and identify new potential prognostic factors for further assessment in prognostic model development and validation.

DESIGN

Retrospective cohort study, employing Cox proportional hazards regression controlling for age, prostate specific antigen (PSA), and Gleason score, was stratified by diagnostic stage.

SETTING

Primary care in England.

PARTICIPANTS

Males with localised prostate cancer diagnosedbetween 01/01/1987 and 31/12/2016 within the Clinical Practice ResearchDatalink database, with linked data from the National Cancer Registration andAnalysis Service and Office for National Statistics.

PRIMARY AND SECONDARY OUTCOMES

Primary outcome measure was prostate cancer mortality. Secondary outcome measures were all-cause mortality and commencing systemic therapy. Up-staging after diagnosis was not used as a secondary outcome owing to significant missing data.

RESULTS

10 901 men (mean age 74.38±9.03 years) with localised prostate cancer were followed up for a mean of 14.12 (±6.36) years. 2331 (21.38%) men underwent systemic therapy and 3450 (31.65%) died, including 1250 (11.47%) from prostate cancer. Factors associated with an increased risk of prostate cancer mortality included age; high PSA; current or ex-smoker; ischaemic heart disease; high C reactive protein; high ferritin; low haemoglobin; high blood glucose and low albumin.

CONCLUSIONS

This study identified several new potential prognostic factors for prostate cancer progression, as well as confirming some known prognostic factors, in an independent primary care data set. Further research is needed to develop and validate a prognostic model for prostate cancer progression.

Cause-specific mortality after diagnosis of cancer among HIV-positive patients: A collaborative analysis of cohort studies

People living with HIV (PLHIV) are more likely than the general population to develop AIDS-defining malignancies (ADMs) and several non-ADMs (NADMs). Information is lacking on survival outcomes and cause-specific mortality after cancer diagnosis among PLHIV. We investigated causes of death within 5 years of cancer diagnosis in PLHIV enrolled in European and North American HIV cohorts starting antiretroviral therapy (ART) 1996-2015, aged ≥16 years, and subsequently diagnosed with cancer. Cancers were grouped: ADMs, viral NADMs and nonviral NADMs. We calculated cause-specific mortality rates (MR) after diagnosis of specific cancers and compared 5-year survival with the UK and France general populations. Among 83,856 PLHIV there were 4,436 cancer diagnoses. Of 603 deaths after ADM diagnosis, 292 (48%) were due to an ADM. There were 467/847 (55%) and 74/189 (39%) deaths that were due to an NADM after nonviral and viral NADM diagnoses, respectively. MR were higher for diagnoses between 1996 and 2005 versus 2006-2015: ADMs 102 (95% CI 92-113) per 1,000 years versus 88 (78-100), viral NADMs 134 (106-169) versus 111 (93-133) and nonviral NADMs 264 (232-300) versus 226 (206-248). Estimated 5-year survival for PLHIV diagnosed with liver (29% [19-39%]), lung (18% [13-23%]) and cervical (75% [63-84%]) cancer was similar to general populations. Survival after Hodgkin's lymphoma diagnosis was lower in PLHIV (75% [67-81%]). Among ART-treated PLHIV diagnosed with cancer, MR and causes of death varied by cancer type, with mortality highest for liver and lung cancers. Deaths within 5 years of NADM diagnoses were more likely to be from cancer than AIDS.

Effects and cost of different strategies to eliminate hepatitis C virus transmission in Pakistan: a modelling analysis

BACKGROUND

The WHO elimination strategy for hepatitis C virus advocates scaling up screening and treatment to reduce global hepatitis C incidence by 80% by 2030, but little is known about how this reduction could be achieved and the costs of doing so. We aimed to evaluate the effects and cost of different strategies to scale up screening and treatment of hepatitis C in Pakistan and determine what is required to meet WHO elimination targets for incidence.

METHODS

We adapted a previous model of hepatitis C virus transmission, treatment, and disease progression for Pakistan, calibrating using available data to incorporate a detailed cascade of care for hepatitis C with cost data on diagnostics and hepatitis C treatment. We modelled the effect on various outcomes and costs of alternative scenarios for scaling up screening and hepatitis C treatment in 2018-30. We calibrated the model to country-level demographic data for 1960-2015 (including population growth) and to hepatitis C seroprevalence data from a national survey in 2007-08, surveys among people who inject drugs (PWID), and hepatitis C seroprevalence trends among blood donors. The cascade of care in our model begins with diagnosis of hepatitis C infection through antibody screening and RNA confirmation. Diagnosed individuals are then referred to care and started on treatment, which can result in a sustained virological response (effective cure). We report the median and 95% uncertainty interval (UI) from 1151 modelled runs.

FINDINGS

One-time screening of 90% of the 2018 population by 2030, with 80% referral to treatment, was projected to lead to 13·8 million (95% UI 13·4-14·1) individuals being screened and 350 000 (315 000-385 000) treatments started annually, decreasing hepatitis C incidence by 26·5% (22·5-30·7) over 2018-30. Prioritised screening of high prevalence groups (PWID and adults aged ≥30 years) and rescreening (annually for PWID, otherwise every 10 years) are likely to increase the number screened and treated by 46·8% and decrease incidence by 50·8% (95% UI 46·1-55·0). Decreasing hepatitis C incidence by 80% is estimated to require a doubling of the primary screening rate, increasing referral to 90%, rescreening the general population every 5 years, and re-engaging those lost to follow-up every 5 years. This approach could cost US$8·1 billion, reducing to $3·9 billion with lowest costs for diagnostic tests and drugs, including health-care savings, and implementing a simplified treatment algorithm.

INTERPRETATION

Pakistan will need to invest about 9·0% of its yearly health expenditure to enable sufficient scale up in screening and treatment to achieve the WHO hepatitis C elimination target of an 80% reduction in incidence by 2030.

FUNDING

UNITAID.

Estimating the risk of acute kidney injury associated with use of diuretics and renin angiotensin aldosterone system inhibitors: A population based cohort study using the clinical practice research datalink

Background

The risk of acute kidney injury (AKI) attributable to renin angiotensin aldosterone (RAAS) inhibitors and diuretics remains unclear.

Methods

We conducted a prospective cohort study using the Clinical Practice Research Datalink (2008–2015) linked to Hospital Episode Statistics – Admitted Patient Care and Office for National Statistics mortality data. Patients were included if they had one or more chronic diagnoses requiring medication. Exposed patients had a first ever prescription for RAAS inhibitors/diuretics during the study period. AKI risk associated with exposure was determined by multivariable Cox regression, propensity score-adjusted Cox regression and a prior event rate ratio (PERR) analysis.

Results

One hundred forty thousand nine hundred fifty-two individuals were included. Increased AKI risk in the exposed group was demonstrated in both the multivariable and propensity score-adjusted cox regressions (HR 1.23 (95% CI 1.04–1.45) and HR 1.24 (1.05–1.47) respectively). The PERR analysis provided a similar overall hazard ratio with a wider confidence interval (HR 1.29 (0.94–1.63)). The increased AKI risk in the exposed group was present only in those receiving two or more antihypertensives. Absolute AKI risk was small.

Conclusions

RAAS inhibitors/diuretics result in an increased risk of AKI. The absolute increase in AKI risk is small, however, and needs to be considered in the context of any potential benefits.

Modelling the potential prevention benefits of a treat-all hepatitis C treatment strategy at global, regional and country levels: A modelling study

The World Health Organization (WHO) recently produced guidelines advising a treat-all policy for HCV to encourage widespread treatment scale-up for achieving HCV elimination. We modelled the prevention impact achieved (HCV infections averted [IA]) from initiating this policy compared with treating different subgroups at country, regional and global levels. We assessed what country-level factors affect impact. A dynamic, deterministic HCV transmission model was calibrated to data from global systematic reviews and UN data sets to simulate country-level HCV epidemics with ongoing levels of treatment. For each country, the model projected the prevention impact (in HCV IA per treatment undertaken) of initiating four treatment strategies; either selected randomly (treat-all) or targeted among people who inject drugs (PWID), people aged ≥35, or those with cirrhosis. The IA was assessed over 20 years. Linear regression was used to identify associations between IA per treatment and demographic factors. Eighty-eight countries (85% of the global population) were modelled. Globally, the model estimated 0.35 (95% credibility interval [95%CrI]: 0.16-0.61) IA over 20 years for every randomly allocated treatment, 0.30 (95%CrI: 0.12-0.53) from treating those aged ≥35 and 0.28 (95%CrI: 0.12-0.49) for those with cirrhosis. Globally, treating PWID achieved 1.27 (95%CrI: 0.68-2.04) IA per treatment. The IA per randomly allocated treatment was positively associated with a country's population growth rate and negatively associated with higher HCV prevalence among PWID. In conclusion, appreciable prevention benefits could be achieved from WHO's treat-all strategy, although greater benefits per treatment can be achieved through targeting PWID. Higher impact will be achieved in countries with high population growth.

Quadruple versus triple combination antiretroviral therapies for treatment naive people with HIV: systematic review and meta-analysis of randomised controlled trials

OBJECTIVE

To evaluate the effects of four drug (quadruple) versus three drug (triple) combination antiretroviral therapies in treatment naive people with HIV, and explore the implications of existing trials for clinical practice and research.

DESIGN

Systematic review and meta-analysis of randomised controlled trials.

DATA SOURCES

PubMed, EMBASE, CENTRAL, Web of Science, and the Cumulative Index to Nursing and Allied Health Literature from March 2001 to December 2016 (updated search in PubMed and EMBASE up to June 2018); and reference lists of eligible studies and related reviews.

STUDY SELECTION

Randomised controlled trials comparing quadruple with triple combination antiretroviral therapies in treatment naive people with HIV and evaluating at least one effectiveness or safety outcome.

REVIEW METHODS

Outcomes of interest included undetectable HIV-1 RNA, CD4 T cell count, virological failure, new AIDS defining events, death, and severe adverse effects. Random effects meta-analyses were conducted.

RESULTS

Twelve trials (including 4251 people with HIV) were eligible. Quadruple and triple combination antiretroviral therapies had similar effects on all relevant effectiveness and safety outcomes, with no point estimates favouring quadruple therapy. With the triple therapy as the reference group, the risk ratio was 0.99 (95% confidence interval 0.93 to 1.05) for undetectable HIV-1 RNA, 1.00 (0.90 to 1.11) for virological failure, 1.17 (0.84 to 1.63) for new AIDS defining events, 1.23 (0.74 to 2.05) for death, and 1.09 (0.89 to 1.33) for severe adverse effects. The mean difference in CD4 T cell count increase between the two groups was -19.55 cells/μL (-43.02 to 3.92). In general, the results were similar, regardless of the specific regimens of combination antiretroviral therapies, and were robust in all subgroup and sensitivity analyses.

CONCLUSION

In this study, effects of quadruple combination antiretroviral therapy were not better than triple combination antiretroviral therapy in treatment naive people with HIV. This finding lends support to current guidelines recommending the triple regimen as first line treatment. Further trials on this topic should be conducted only when new research is justified by adequate systematic reviews of the existing evidence. However, this study cannot exclude the possibility that quadruple cART would be better than triple cART when new classes of antiretroviral drugs are made available.

Associations of mortality with own blood pressure using son's blood pressure as an instrumental variable

High systolic blood pressure (SBP) causes cardiovascular disease (CVD) and is associated with mortality from other causes, but conventional multivariably-adjusted results may be confounded. Here we used a son’s SBP (>1 million Swedish men) as an instrumental variable for parental SBP and examined associations with parents’ cause-specific mortality, avoiding reverse causation. The hazard ratio for CVD mortality per SD (10.80 mmHg) of SBP was 1.49 (95% CI: 1.43, 1.56); SBP was positively associated with coronary heart disease and stroke. SBP was also associated positively with all-cause, diabetes and kidney cancer mortality, and negatively with external causes. Negative associations with respiratory-related mortality were probably confounded by smoking. Hazard ratios for other causes were imprecise or null. Diastolic blood pressure gave similar results to SBP. CVD hazard ratios were intermediate between those from conventional multivariable studies and Mendelian randomization and stronger than those from clinical trials, approximately consistent with an effect of exposure duration on effect sizes. Plots of parental mortality against offspring SBP were approximately linear, supporting calls for lower SBP targets. Results suggest that conventional multivariable analyses of mortality and SBP are not substantially confounded by reverse causation and confirm positive effects of SBP on all-cause, CVD and diabetes mortality.

The contribution of injection drug use to hepatitis C virus transmission globally, regionally, and at country level: a modelling study

BACKGROUND

WHO aims to eliminate the hepatitis C virus (HCV) as a public health threat by 2030. Injection drug use is an important risk factor for HCV transmission, but its contribution to country-level and global epidemics is unknown. We estimated the contribution of injection drug use to risk for HCV epidemics globally, regionally, and at country level.

METHODS

We developed a dynamic deterministic HCV transmission model to simulate country-level HCV epidemics among people who inject drugs and the general population. Each country's model was calibrated using country-specific data from UN datasets and systematic reviews on the prevalence of HCV and injection drug use. The population attributable fraction of HCV transmission associated with injection drug use was estimated-defined here as the percentage of HCV infections prevented if additional HCV transmission due to injection drug use was removed between 2018 and 2030.

FINDINGS

The model included 88 countries (85% of the global population). The model predicted 0·23% (95% credibility interval [CrI] 0·16-0·31) of the global population were injection drug users in 2017, and 8% (5-12) of prevalent HCV infections were among people who currently inject drugs. Globally, if the increased risk for HCV transmission among people who inject drugs was removed, an estimated 43% (95% CrI 25-67) of incident HCV infections would be prevented from 2018 to 2030, varying regionally. This population attributable fraction was higher in high-income countries (79%, 95% CrI 57-97) than in countries of low and middle income (38%, 24-64) and was associated with the percentage of a country's prevalent HCV infections that are among people who inject drugs.

INTERPRETATION

Unsafe injecting practices among people who inject drugs contribute substantially to incident HCV infections globally. Any intervention that can reduce HCV transmission among people who inject drugs will have a pronounced effect on country-level incidence of HCV.

FUNDING

None.

Qualitative evaluation of a pilot educational intervention to increase primary care HIV-testing

BACKGROUND

UK guidelines recommend a 'routine offer of HIV testing' in primary care where HIV diagnosed prevalence exceeds 2 in 1000. However, current primary care HIV testing rates are low. Efforts to increase primary care HIV testing are needed. To examine how an educational intervention to increase HIV testing in general practice was experienced by healthcare professionals (HCPs) and to understand the perceived impacts on HIV testing.

METHOD

Qualitative interviews with general practitioners (GPs) and nurses 3-months after receiving an educational intervention developed from an adapted version of the Medical Foundation for HIV and Sexual Health (MEDFASH) HIV Testing In Practice (TIPs) online educational tool which included training on HIV associated clinical indicator conditions, why, who, and how to test. The intervention was delivered in 19 high-HIV prevalence general practices in Bristol. 27 semi-structured interviews were conducted across 13 practices with 16 GPs, 10 nurses and the sexual health clinician who delivered the intervention. Transcripts were analysed thematically informed by Normalisation Process Theory.

RESULTS

HCPs welcomed the opportunity to update their HIV knowledge through a tailored, interactive session. Post-training, HCPs reported increased awareness of HIV indicator conditions, confidence to offer HIV tests and consideration of HIV tests. Continued testing barriers include perceived lack of opportunity.

CONCLUSIONS

This qualitative study found that HIV education is perceived as valuable in relation to perceived awareness, confidence, and consideration of HIV testing. However, repetition and support from other strategies are needed to encourage HCPs to offer HIV tests. Future interventions should consider using behaviour change theory to develop a complex intervention that addresses not only HCP capability to offer an HIV test, but also issues of opportunity and motivation.

Increased non-AIDS mortality among persons with AIDS-defining events after antiretroviral therapy initiation

INTRODUCTION

HIV-1 infection leads to chronic inflammation and to an increased risk of non-AIDS mortality. Our objective was to determine whether AIDS-defining events (ADEs) were associated with increased overall and cause-specific non-AIDS related mortality after antiretroviral therapy (ART) initiation.

METHODS

We included HIV treatment-naïve adults from the Antiretroviral Therapy Cohort Collaboration (ART-CC) who initiated ART from 1996 to 2014. Causes of death were assigned using the Coding Causes of Death in HIV (CoDe) protocol. The adjusted hazard ratio (aHR) for overall and cause-specific non-AIDS mortality among those with an ADE (all ADEs, tuberculosis (TB), Pneumocystis jiroveci pneumonia (PJP), and non-Hodgkin's lymphoma (NHL)) compared to those without an ADE was estimated using a marginal structural model.

RESULTS

The adjusted hazard of overall non-AIDS mortality was higher among those with any ADE compared to those without any ADE (aHR 2.21, 95% confidence interval (CI) 2.00 to 2.43). The adjusted hazard of each of the cause-specific non-AIDS related deaths were higher among those with any ADE compared to those without, except metabolic deaths (malignancy aHR 2.59 (95% CI 2.13 to 3.14), accident/suicide/overdose aHR 1.37 (95% CI 1.05 to 1.79), cardiovascular aHR 1.95 (95% CI 1.54 to 2.48), infection aHR (95% CI 1.68 to 2.81), hepatic aHR 2.09 (95% CI 1.61 to 2.72), respiratory aHR 4.28 (95% CI 2.67 to 6.88), renal aHR 5.81 (95% CI 2.69 to 12.56) and central nervous aHR 1.53 (95% CI 1.18 to 5.44)). The risk of overall and cause-specific non-AIDS mortality differed depending on the specific ADE of interest (TB, PJP, NHL).

CONCLUSIONS

In this large multi-centre cohort collaboration with standardized assignment of causes of death, non-AIDS mortality was twice as high among patients with an ADE compared to without an ADE. However, non-AIDS related mortality after an ADE depended on the ADE of interest. Although there may be unmeasured confounders, these findings suggest that a common pathway may be independently driving both ADEs and NADE mortality. While prevention of ADEs may reduce subsequent death due to NADEs following ART initiation, modification of risk factors for NADE mortality remains important after ADE survival.

Curbing the hepatitis C virus epidemic in Pakistan: the impact of scaling up treatment and prevention for achieving elimination

Background

The World Health Organization (WHO) has developed a global health strategy to eliminate viral hepatitis. We project the treatment and prevention requirements to achieve the WHO HCV elimination target of reducing HCV incidence by 80% and HCV-related mortality by 65% by 2030 in Pakistan, which has the second largest HCV burden worldwide.

Methods

We developed an HCV transmission model for Pakistan, and calibrated it to epidemiological data from a national survey (2007), surveys among people who inject drugs (PWID), and blood donor data. Current treatment coverage data came from expert opinion and published reports. The model projected the HCV burden, including incidence, prevalence and deaths through 2030, and estimated the impact of varying prevention and direct-acting antiviral (DAA) treatment interventions necessary for achieving the WHO HCV elimination targets.

Results

With no further treatment (currently ∼150 000 treated annually) during 2016–30, chronic HCV prevalence will increase from 3.9% to 5.1%, estimated annual incident infections will increase from 700 000 to 1 100 000, and 1 400 000 HCV-associated deaths will occur. To reach the WHO HCV elimination targets by 2030, 880 000 annual DAA treatments are required if prevention is not scaled up and no treatment prioritization occurs. By targeting treatment toward persons with cirrhosis (80% treated annually) and PWIDs (double the treatment rate of non-PWIDs), the required annual treatment number decreases to 750 000. If prevention activities also halve transmission risk, this treatment number reduces to 525 000 annually.

Conclusions

Substantial HCV prevention and treatment interventions are required to reach the WHO HCV elimination targets in Pakistan, without which Pakistan’s HCV burden will increase markedly.

Evaluation of an educational intervention to increase HIV-testing in high HIV prevalence general practices: a pilot feasibility stepped-wedged randomised controlled trial

BACKGROUND

HIV-infected patients often present to primary care several times with HIV-indicator conditions before diagnosis but the opportunity to test by healthcare professionals (HCPs) is frequently missed. Current HIV testing rates in primary care are low and educational interventions to facilitate HCPs to increase testing and awareness of HIV are needed.

METHOD

We implemented a pilot feasibility stepped-wedged randomised controlled trial of an educational intervention in high HIV prevalence practices in Bristol. The training delivered to HCPs including General Practitioners (GP) aimed to increase HIV testing and included why, who, and how to test. The intervention was adapted from the Medical Foundation for HIV and Sexual Health HIV Testing in Practice (MEDFASH) educational tool. Questionnaires assessed HCP feedback and perceived impacts of the intervention. HIV testing rates were compared between control and intervention practices using 12 monthly laboratory totals.

RESULTS

169 HCPs (from 19 practices) received the educational intervention. 127 (75%) questionnaires were completed. Delivery of the intervention was received positively and was perceived as valuable for increasing awareness, confidence and consideration of testing, with HCPs gaining more awareness of HIV testing guidelines. The main pre-training HIV testing barrier reported by GPs was the patient not considering themselves at risk, whilst for nurses it was a concern about embarrassing or offending the patient. Most HCPs reported the intervention addressed these barriers. The HIV testing rate increased more in the control than in the intervention practices: mean difference 2.6 (95% CI 0.5,4.7) compared with 1.9 (- 0.5,4.3) per 1000 patients, respectively. The number of HIV tests across all practices increased from 1154 in the first 6 months to 1299 in the second 6 months, an annual increase in testing rate of 2.0 (0.7,3.4) from 16.3 to 18.3 per 1000 patients.

CONCLUSION

There was a small increase in HIV testing rates over the study period, but this could not be attributed to the educational intervention. More effective and sustainable programmes tailored to each practice context are needed to change testing culture and HCP behaviour. Repeated training, supported by additional measures, such as testing prompts, may be needed to influence primary care HIV testing.

Developing and validating Parkinson's disease subtypes and their motor and cognitive progression

OBJECTIVES

To use a data-driven approach to determine the existence and natural history of subtypes of Parkinson's disease (PD) using two large independent cohorts of patients newly diagnosed with this condition.

METHODS

1601 and 944 patients with idiopathic PD, from Tracking Parkinson's and Discovery cohorts, respectively, were evaluated in motor, cognitive and non-motor domains at the baseline assessment. Patients were recently diagnosed at entry (within 3.5 years of diagnosis) and were followed up every 18 months. We used a factor analysis followed by a k-means cluster analysis, while prognosis was measured using random slope and intercept models.

RESULTS

We identified four clusters: (1)  fast motor progression with symmetrical motor disease, poor olfaction, cognition and postural hypotension; (2) mild motor and non-motor disease with intermediate motor progression; (3) severe motor disease, poor psychological well-being and  poor sleep with an intermediate motor progression; (4) slow motor progression with tremor-dominant, unilateral disease. Clusters were moderately to substantially stable across the two cohorts (kappa 0.58). Cluster 1 had the fastest motor progression in Tracking Parkinson's at 3.2 (95% CI 2.8 to 3.6) UPDRS III points per year while cluster 4 had the slowest at 0.6 (0.1-1.1). In Tracking Parkinson's, cluster 2 had the largest response to levodopa 36.3% and cluster 4 the lowest 28.8%.

CONCLUSIONS

We have found four novel clusters that replicated well across two independent early PD cohorts and were associated with levodopa response and motor progression rates. This has potential implications for better understanding disease pathophysiology and the relevance of patient stratification in future clinical trials.

Usage of low dead space syringes and association with hepatitis C prevalence amongst people who inject drugs in the UK

INTRODUCTION

Syringes with attached needles (low dead space syringes [LDSS]) retain far less blood following injection than syringes with detachable needles (high dead space syringes [HDSS]). People who inject drugs (PWID) who share needles/syringes may be less likely to acquire Hepatitis C virus (HCV) infection using LDSS, compared with HDSS, but data are limited.

METHODS

Utilizing drug behavior and HCV antibody testing data from the UK 2014/2015 Unlinked Anonymous Monitoring Survey of PWID, we calculated the percentage of syringes used in the past month that were LDSS. We investigated which injecting characteristics and demographic factors were associated with 100% LDSS (against 0-99%) usage, and whether 100% LDSS use was associated with antibody HCV-status, after adjusting for confounders.

RESULT

Of 2174 participants, 55% always used LDSS, 27% always used HDSS, and 17% used both LDSS and HDSS. PWID that had injected into their groin during the past month were unlikely to use LDSS, adjusted odds ratio (aOR) 0.14 (95% confidence interval 0.11-0.17), compared to those not using the groin. Those injecting crack were less likely to use LDSS than those not, aOR 0.79 (0.63-0.98). Polydrug use was negatively associated with LDSS use, aOR 0.88 (0.79-0.98) per additional drug. LDSS use was associated with lower prevalent HCV among all PWID (aOR 0.77, [0.64-0.93]), which was stronger among recent initiates (aOR 0.53 [0.30-0.94]) than among experienced PWID (aOR 0.81 [0.66-0.99]).

DISCUSSION

People who inject into their groin were less likely to use LDSS. Exclusive LDSS use was associated with lower prevalence of HCV amongst PWID that started injecting recently, suggesting LDSS use is protective against HCV.

Identifying Risk of Viral Failure in Treated HIV-Infected Patients Using Different Measures of Adherence: The Antiretroviral Therapy Cohort Collaboration

Adherence to antiretroviral therapy (ART) is critical for successful treatment of Human Immunodeficiency Virus (HIV), but comparisons across settings are difficult because adherence is measured in different ways. We examined utility of different adherence measures for identification of patients at risk of viral failure (VF). Eight cohorts in the ART Cohort Collaboration contributed data from pharmacy refills or self-report questionnaires collected between 1996 and 2013 (N = 11689). For pharmacy data (N = 7156), we examined associations of percentage adherence during the 1st year of ART with VF (>500 copies/mL) at 1 year. For self-report data (N = 4533), we examined 28-day adherence with VF based on closest viral load measure within 6 months after questionnaire date. Since adherence differed markedly by measurement type, we defined different cut-off points for pharmacy (lower <45%, medium 45–99%, higher 100%) and self-report (lower ≤95%, medium 96–99%, higher 100%) data. Adjusted odds ratios (ORs) for VF in lower and medium, compared to higher adherence groups, were 23.04 (95% CI: 18.44–28.78) and 3.84 (3.36–4.39) for pharmacy data. For self-report data, they were 3.19 (2.31–4.40) and 1.08 (0.80–1.46). Both types of measure were strongly associated with VF. Although adherence measurements over longer time-frames are preferable for prediction, they are less useful for intervention.

Derivative estimation for longitudinal data analysis: Examining features of blood pressure measured repeatedly during pregnancy

Estimating velocity and acceleration trajectories allows novel inferences in the field of longitudinal data analysis, such as estimating change regions rather than change points, and testing group effects on nonlinear change in an outcome (ie, a nonlinear interaction). In this article, we develop derivative estimation for 2 standard approaches-polynomial mixed models and spline mixed models. We compare their performance with an established method-principal component analysis through conditional expectation through a simulation study. We then apply the methods to repeated blood pressure (BP) measurements in a UK cohort of pregnant women, where the goals of analysis are to (i) identify and estimate regions of BP change for each individual and (ii) investigate the association between parity and BP change at the population level. The penalized spline mixed model had the lowest bias in our simulation study, and we identified evidence for BP change regions in over 75% of pregnant women. Using mean velocity difference revealed differences in BP change between women in their first pregnancy compared with those who had at least 1 previous pregnancy. We recommend the use of penalized spline mixed models for derivative estimation in longitudinal data analysis.

The use of funnel plots with regression as a tool to visually compare HIV treatment outcomes between centres adjusting for patient characteristics and size: a UK Collaborative HIV Cohort study

Objectives

A measure used for assessing the effectiveness of HIV care and comparing clinical centres is the proportion of people starting antiretroviral therapy (ART) with viral suppression (VS) after 1 year. We propose a method that adjusts for patients’ demographic characteristics, and visually compares this measure between different sites accounting for centre size.

Methods

We analysed viral load measurements for UK Collaborative HIV Cohort (UK CHIC) patients starting ART between 2006 and 2013. We used logistic regression to estimate the proportion with VS after 1 year of ART adjusted for patient mix (in terms of age and a combined gender/ethnicity/acquisition mode variable) and calendar year. We compared outcomes between centres using funnel plots which account for centre size.

Results

The overall proportion of the cohort with VS 1 year after starting ART was 90% and increased from 83% to 93% between 2006 and 2013. VS was lower in younger individuals. White men who have sex with men (MSM) had the highest (94%), and black African (81%) and white (82%) heterosexual women the lowest proportions achieving VS. Comparing the unadjusted funnel plot with the adjusted, there were movements of some centres from outside to inside the 95% contour limits, which was largely explained by the patient mix of these centres.

Conclusions

VS 1 year after ART start was associated with demographic characteristics and centre size; therefore, to compare the performances of centres, adjustment for these factors is required. Adjusted funnel plot is an effective tool which accounts for both the demographic characteristics and the centre size. Social factors, rather than treatment decisions within the control of the centres, may drive differences in outcomes.

CD4:CD8 Ratio and CD8 Count as Prognostic Markers for Mortality in Human Immunodeficiency Virus-Infected Patients on Antiretroviral Therapy: The Antiretroviral Therapy Cohort Collaboration (ART-CC)

Background

We investigated whether CD4:CD8 ratio and CD8 count were prognostic for all-cause, AIDS, and non-AIDS mortality in virologically suppressed patients with high CD4 count.

Methods

We used data from 13 European and North American cohorts of human immunodeficiency virus–infected, antiretroviral therapy (ART)–naive adults who started ART during 1996–2010, who were followed from the date they had CD4 count ≥350 cells/μL and were virologically suppressed (baseline). We used stratified Cox models to estimate unadjusted and adjusted (for sex, people who inject drugs, ART initiation year, and baseline age, CD4 count, AIDS, duration of ART) all-cause and cause-specific mortality hazard ratios for tertiles of CD4:CD8 ratio (0–0.40, 0.41–0.64 [reference], >0.64) and CD8 count (0–760, 761–1138 [reference], >1138 cells/μL) and examined the shape of associations using cubic splines.

Results

During 276526 person-years, 1834 of 49865 patients died (249 AIDS-related; 1076 non-AIDS-defining; 509 unknown/unclassifiable deaths). There was little evidence that CD4:CD8 ratio was prognostic for all-cause mortality after adjustment for other factors: the adjusted hazard ratio (aHR) for lower vs middle tertile was 1.11 (95% confidence interval [CI], 1.00–1.25). The association of CD8 count with all-cause mortality was U-shaped: aHR for higher vs middle tertile was 1.13 (95% CI, 1.01–1.26). AIDS-related mortality declined with increasing CD4:CD8 ratio and decreasing CD8 count. There was little evidence that CD4:CD8 ratio or CD8 count was prognostic for non-AIDS mortality.

Conclusions

In this large cohort collaboration, the magnitude of adjusted associations of CD4:CD8 ratio or CD8 count with mortality was too small for them to be useful as independent prognostic markers in virally suppressed patients on ART.

Using observational data to emulate a randomized trial of dynamic treatment-switching strategies: an application to antiretroviral therapy

Background

When a clinical treatment fails or shows suboptimal results, the question of when to switch to another treatment arises. Treatment switching strategies are often dynamic because the time of switching depends on the evolution of an individual's time-varying covariates. Dynamic strategies can be directly compared in randomized trials. For example, HIV-infected individuals receiving antiretroviral therapy could be randomized to switching therapy within 90 days of HIV-1 RNA crossing above a threshold of either 400 copies/ml (tight-control strategy) or 1000 copies/ml (loose-control strategy).

Methods

We review an approach to emulate a randomized trial of dynamic switching strategies using observational data from the Antiretroviral Therapy Cohort Collaboration, the Centers for AIDS Research Network of Integrated Clinical Systems and the HIV-CAUSAL Collaboration. We estimated the comparative effect of tight-control vs. loose-control strategies on death and AIDS or death via inverse-probability weighting.

Results

Of 43 803 individuals who initiated an eligible antiretroviral therapy regimen in 2002 or later, 2001 met the baseline inclusion criteria for the mortality analysis and 1641 for the AIDS or death analysis. There were 21 deaths and 33 AIDS or death events in the tight-control group, and 28 deaths and 41 AIDS or death events in the loose-control group. Compared with tight control, the adjusted hazard ratios (95% confidence interval) for loose control were 1.10 (0.73, 1.66) for death, and 1.04 (0.86, 1.27) for AIDS or death.

Conclusions

Although our effective sample sizes were small and our estimates imprecise, the described methodological approach can serve as an example for future analyses.

Cinacalcet use and the risk of cardiovascular events, fractures and mortality in chronic kidney disease patients with secondary hyperparathyroidism

With the aim to expand the randomized controlled trial evidence of cinacalcet treatment to the unselected, general chronic kidney disease (CKD) population we analysed a large inception cohort of CKD patients in the region of Stockholm, Sweden 2006-2012 (both non-dialysis, dialysis and transplanted) with evidence of secondary hyperparathyroidism (SHPT). We used marginal structural models to account for both confounding by indication and time-dependent confounding. Over 37 months, 435/3,526 (12%) initiated cinacalcet de novo. Before cinacalcet initiation, parathyroid hormone (PTH) had increased progressively to a median of 636ng/L. After cinacalcet initiation, PTH declined, as did serum calcium and phosphate. In total, 42% of patients experienced a fatal/non-fatal cardiovascular event, 32% died and 9% had a new fracture. The unadjusted cardiovascular odds ratio (OR) associated with cinacalcet treatment was 1.01 (95% confidence interval: 0.83, 1.22). In the fully weighted model, the cardiovascular odds was lower in cinacalcet treated patients (OR 0.67: 0.48, 0.93). The adjusted ORs for all-cause mortality and for fractures were 0.79 (0.56, 1.11) and 1.08 (0.59, 1.98) respectively. Our study suggests cinacalcet treatment improves biochemical abnormalities in the wider CKD population, and adds real-world support that treating SHPT with cinacalcet may have beneficial effects on cardiovascular outcomes.

Predicting prostate cancer progression: protocol for a retrospective cohort study to identify prognostic factors for prostate cancer outcomes using routine primary care data

INTRODUCTION

Prostate cancer is the most common cancer in men in the UK, with nearly 40 000 diagnosed in 2014; and it is the second most common cause of male cancer-related mortality. The clinical conundrum is that most men live with prostate cancer rather than die from it, while existing treatments have significant associated morbidity. Recent studies have shown very low mortality rates (1% after a median of 10-year follow-up) and no treatment-related reductions in mortality, in men with localised prostate cancer. This study will identify prognostic factors associated with prostate cancer progression to help differentiate aggressive from more indolent tumours in men with localised disease at diagnosis, and so inform the decision to adopt conservative (active surveillance) or radical (surgery or radiotherapy) management strategies.

METHODS AND ANALYSIS

The Clinical Practice Research Datalink (CPRD) contains 57 318 men who were diagnosed with prostate cancer between 1 January 1987 and 31 December 2016. These men will be linked to the Office for National Statistics (ONS) and the National Cancer Registration and Analysis Service registry databases for mortality, TNM stage, Gleason grade and treatment data. Men with a diagnosis date prior to 1 January 1987 and men with lymph node or distant metastases at diagnosis will be excluded. A priori determined prognostic factors potentially associated with prostate cancer mortality, the end point of cancer progression, will be measured at baseline, and the participants followed through to development of cancer progression, death or the end of the follow-up period (31 December 2016). Cox proportional hazards regression will be used to estimate crude and mutually adjusted HRs. Mortality risk will be predicted using flexible parametric survival models that can accurately fit the shape of the hazard function.

ETHICS AND DISSEMINATION

This study protocol has approval from the Independent Scientific Advisory Committee for the UK Medicines and Healthcare products Regulatory Agency Database Research (protocol 17_041). The findings will be presented in peer-reviewed journals and local CPRD researcher meetings.

Application of causal inference methods in the analyses of randomised controlled trials: a systematic review

BACKGROUND

Applications of causal inference methods to randomised controlled trial (RCT) data have usually focused on adjusting for compliance with the randomised intervention rather than on using RCT data to address other, non-randomised questions. In this paper we review use of causal inference methods to assess the impact of aspects of patient management other than the randomised intervention in RCTs.

METHODS

We identified papers that used causal inference methodology in RCT data from Medline, Premedline, Embase, Cochrane Library, and Web of Science from 1986 to September 2014, using a forward citation search of five seminal papers, and a keyword search. We did not include studies where inverse probability weighting was used solely to balance baseline characteristics, adjust for loss to follow-up or adjust for non-compliance to randomised treatment. Studies where the exposure could not be assigned were also excluded.

RESULTS

There were 25 papers identified. Nearly half the papers (11/25) estimated the causal effect of concomitant medication on outcome. The remainder were concerned with post-randomisation treatment regimens (sequential treatments, n =5 ), effects of treatment timing (n = 2) and treatment dosing or duration (n = 7). Examples were found in cardiovascular disease (n = 5), HIV (n = 7), cancer (n = 6), mental health (n = 4), paediatrics (n = 2) and transfusion medicine (n = 1). The most common method implemented was a marginal structural model with inverse probability of treatment weighting.

CONCLUSIONS

Examples of studies which exploit RCT data to address non-randomised questions using causal inference methodology remain relatively limited, despite the growth in methodological development and increasing utilisation in observational studies. Further efforts may be needed to promote use of causal methods to address additional clinical questions within RCTs to maximise their value.

A novel strategy to reduce very late HIV diagnosis in high-prevalence areas in South-West England: serious incident audit

Background

Very late diagnosis of HIV is a serious public health issue. We used serious incident reporting (SIR) to identify and address reasons for late diagnoses across the patient pathway.

Methods

Cases of very late HIV diagnosis were reported via SIR in two 6-month batches between 2011 and 2012 in Bournemouth, Poole and Bristol. Case notes were reviewed for missed opportunities for earlier diagnosis using a root-cause analysis tool.

Results

A total of 33 patients (aged 30-67 years, 66% male) were diagnosed very late. Although the majority were white British (n = 17), Black African (n = 9) and Eastern European (n = 4) ethnicities were over-represented. Twenty-four (73%) patients had clinical indicator conditions for HIV, 30 (91%) had a risk factor for HIV acquisition, with 13 (39%) having 2 or more (men-who-have-sex-with-men (n = 11), partner HIV positive (n = 11), from high-prevalence area (n = 12)). Actions resulting from SIR included increasing awareness of indicator conditions, HIV education days within primary care, and initiatives to increase testing within hospital specialities.

Conclusions

SIR allowed identification of reasons for very late HIV diagnosis and provided an impetus for initiatives to address them. SIR may be part of an effective strategy to prevent late diagnosis of HIV which would have important benefits for individual and population health.

Estimating the impact of antiretroviral treatment on adult mortality trends in South Africa: A mathematical modelling study

BACKGROUND

Substantial reductions in adult mortality have been observed in South Africa since the mid-2000s, but there has been no formal evaluation of how much of this decline is attributable to the scale-up of antiretroviral treatment (ART), as previous models have not been calibrated to vital registration data. We developed a deterministic mathematical model to simulate the mortality trends that would have been expected in the absence of ART, and with earlier introduction of ART.

METHODS AND FINDINGS

Model estimates of mortality rates in ART patients were obtained from the International Epidemiology Databases to Evaluate AIDS-Southern Africa (IeDEA-SA) collaboration. The model was calibrated to HIV prevalence data (1997-2013) and mortality data from the South African vital registration system (1997-2014), using a Bayesian approach. In the 1985-2014 period, 2.70 million adult HIV-related deaths occurred in South Africa. Adult HIV deaths peaked at 231,000 per annum in 2006 and declined to 95,000 in 2014, a reduction of 74.7% (95% CI: 73.3%-76.1%) compared to the scenario without ART. However, HIV mortality in 2014 was estimated to be 69% (95% CI: 46%-97%) higher in 2014 (161,000) if the model was calibrated only to HIV prevalence data. In the 2000-2014 period, the South African ART programme is estimated to have reduced the cumulative number of HIV deaths in adults by 1.72 million (95% CI: 1.58 million-1.84 million) and to have saved 6.15 million life years in adults (95% CI: 5.52 million-6.69 million). This compares with a potential saving of 8.80 million (95% CI: 7.90 million-9.59 million) life years that might have been achieved if South Africa had moved swiftly to implement WHO guidelines (2004-2013) and had achieved high levels of ART uptake in HIV-diagnosed individuals from 2004 onwards. The model is limited by its reliance on all-cause mortality data, given the lack of reliable cause-of-death reporting, and also does not allow for changes over time in tuberculosis control programmes and ART effectiveness.

CONCLUSIONS

ART has had a dramatic impact on adult mortality in South Africa, but delays in the rollout of ART, especially in the early stages of the ART programme, have contributed to substantial loss of life. This is the first study to our knowledge to calibrate a model of ART impact to population-level recorded death data in Africa; models that are not calibrated to population-level death data may overestimate HIV-related mortality.

Importance and Contribution of Community, Social, and Healthcare Risk Factors for Hepatitis C Infection in Pakistan

Pakistan has a high prevalence of hepatitis C virus (HCV) infection, estimated at 4.9% (2,290/46,843) in the 2007 national HCV seroprevalence survey. We used data from this survey to assess the importance of risk factor associations with HCV prevalence in Pakistan. Exposures were grouped as community (going to the barbers, sharing smoking equipment, having an ear/nose piercing, tattoo, or acupuncture), healthcare (ever having hemodialysis, blood transfusion, or ≥ 5 injections in the last year), demographic (marital status and age), and socio-economic (illiterate or laborer). We used mutually adjusted multivariable regression analysis, stratified by sex, to determine associations with HCV infection, their population attributable fraction, and how risk of infection accumulates with multiple exposures. Strength of associations was assessed using adjusted odds ratios (aOR). Community [aOR females 1.5 (95% confidence interval [CI]: 1.2, 1.8); males 1.2 (1.1, 1.4)] and healthcare [females 1.4 (1.2, 1.6); males 1.2 (1.1, 1.4)] exposures, low socio-economic status [females 1.6 (1.3, 1.80); males 1.3 (1.2, 1.5)], and marriage [females 1.5 (1.2, 1.9); males 1.4 (1.1, 1.8)] were associated with increased HCV infection. Among married women, the number of children was associated with an increase in HCV infection; linear trend aOR per child 1.06 (1.01, 1.11). Fewer infections could be attributed to healthcare exposures (females 13%; males 6%) than to community exposures (females 25%; males 9%). Prevalence increased from 3% to 10% when cumulative exposures increased from 1 to ≥ 4 [aOR per additional exposure for females 1.5 (1.4, 1.6); males 1.2 (1.2, 1.3)]. A combination of community, healthcare, and other factors appear to drive the Pakistan HCV epidemic, highlighting the need for a comprehensive array of prevention strategies.

Cross-sectional study to evaluate Trichomonas vaginalis positivity in women tested for Neisseria gonorrhoeae and Chlamydia trachomatis, attending genitourinary medicine and primary care clinics in Bristol, South West England

BACKGROUND

Highly sensitive, commercial nucleic acid amplification tests (NAAT) for Trichomonas vaginalis have only recently been recommended for use in the UK. While testing for T. vaginalis is routine in symptomatic women attending genitourinary medicine (GUM) clinics, it is rare in asymptomatic women or those attending primary care. The aim of this study was to evaluate the positivity of T. vaginalis using a commercial NAAT, in symptomatic and asymptomatic women undergoing testing for chlamydia and gonorrhoea in GUM and primary care settings.

METHODS

Samples from 9186 women undergoing chlamydia and gonorrhoea testing in South West England between May 2013 and Jan 2015 were also tested for T. vaginalis by NAAT alongside existing tests.

RESULTS

T. vaginalis positivity using NAAT was as follows: in GUM 4.5% (24/530, symptomatic) and 1.7% (27/1584, asymptomatic); in primary care 2.7% (94/3499, symptomatic) and 1.2% (41/3573, asymptomatic). Multivariable regression found that in GUM older age, black ethnicity and deprivation were independent risk factors for T. vaginalis infection. Older age and deprivation were also risk factors in primary care. Testing women presenting with symptoms in GUM and primary care using TV NAATs is estimated to cost £260 per positive case diagnosed compared with £716 using current microbiological tests.

CONCLUSIONS

Aptima TV outperforms existing testing methods used to identify T. vaginalis infection in this population. An NAAT should be used when testing for T. vaginalis in women who present for testing with symptoms in primary care and GUM, based on test performance and cost.

Benchmarked performance charts using principal components analysis to improve the effectiveness of feedback for audit data in HIV care

BACKGROUND

Feedback tools for clinical audit data that compare site-specific results to average performance over all sites can be useful for quality improvement. Proposed tools should be simple and clearly benchmark the site's performance, so that a relevant action plan can be directly implemented to improve patient care services. We aimed to develop such a tool in order to feedback data to UK HIV clinics participating in the 2015 British HIV Association (BHIVA) audit assessing compliance with the 2011 guidelines for routine investigation and monitoring of adult HIV-1- infected individuals.

METHODS

HIV clinic sites were asked to provide data on a random sample of 50-100 adult patients attending for HIV care during 2014 and/or 2015 by completing a self-audit spreadsheet. Outcomes audited included the proportion of patients with recorded resistance testing, viral load monitoring, adherence assessment, medications, hepatitis testing, vaccination management, risk assessments, and sexual health screening. For each outcome we benchmarked the proportion for a specific site against the average performance. We produced performance charts for each site using boxplots for the outcomes. We also used the mean and differences from the mean performance to produce a dashboard for each site. We used principal components analysis to group correlated outcomes and simplify the dashboard.

RESULTS

The 106 sites included in the study provided information on a total of 7768 patients. Outcomes capturing monitoring of treatment of HIV-infection showed high performance across the sites, whereas testing for hepatitis, and risk assessment for cardiovascular disease and smoking, management of flu vaccination, sexual health screening, and cervical cytology for women were very variable across sites. The principal components analysis reduced the original 12 outcomes to four factors that represented HIV care, hepatitis testing, other screening tests, and resistance testing. These provided simplified measures of adherence to guidelines which were presented as a 4 bar dashboard of performance.

CONCLUSION

Our dashboard performance charts provide easily digestible visual summaries of locally relevant audit data that are benchmarked against the overall mean and can be used to improve feedback to HIV services. Feedback from clinicians indicated that they found these charts acceptable and useful.

First estimates of the global and regional incidence of neonatal herpes infection

Background

Neonatal herpes is a rare but potentially devastating condition (60% fatality without treatment). Transmission usually occurs during delivery from mothers with herpes simplex virus type 1 (HSV-1) or HSV-2 genital infection. The global burden has never been quantified. We developed a novel methodology for burden estimation and present first WHO global and regional estimates of the annual number of neonatal herpes cases during 2010–2015.

Methods

Previous estimates of HSV-1 and HSV-2 prevalence and incidence in women aged 15–49 years were applied to 2010–2015 birth rates to estimate infections during pregnancy. Published risks of neonatal HSV transmission were then applied according to whether maternal infection was incident or prevalent with HSV-1 or HSV-2 to estimate neonatal herpes cases.

Findings

Globally the overall rate of neonatal herpes was estimated to be ~10 cases per 100,000 births, equivalent to a best-estimate of ~14,000 cases annually (HSV-1: ~4,000; HSV-2: ~10,000). We estimated that the most neonatal herpes cases occurred in Africa, due to high maternal HSV-2 infection and high birth rates. HSV-1 contributed more cases than HSV-2 in the Americas, Europe and Western Pacific. High rates of genital HSV-1 infection and moderate HSV-2 prevalence meant the Americas had the highest overall rate. However, our estimates are highly sensitive to the core assumptions, and considerable uncertainty exists for many settings given sparse underlying data.

Interpretation

These neonatal herpes estimates mark the first attempt to quantify the global burden of this rare but serious condition. Better primary data collection on neonatal herpes is critically needed to reduce uncertainty and refine future estimates. This is particularly important in resource-poor settings where we may have underestimated cases. Nevertheless, these first estimates suggest development of new HSV prevention measures such as vaccines could have additional benefits beyond reducing genital ulcer disease and HSV-associated HIV transmission, through prevention of neonatal herpes.

Funding

World Health Organization

Analysis of trends in adolescent suicides and accidental deaths in England and Wales, 1972-2011

BACKGROUND

Previous analyses of adolescent suicides in England and Wales have focused on short time periods.

AIMS

To investigate trends in suicide and accidental deaths in adolescents between 1972 and 2011.

METHOD

Time trend analysis of rates of suicides and deaths from accidental poisoning and hanging in 10- to 19-year-olds by age, gender and deprivation. Rate ratios were estimated for 1982-1991, 1992-2001 and 2002-2011 with 1972-1981 as comparator.

RESULTS

Suicide rates have remained stable in 10- to 14-year-olds, with strong evidence for a reduction in accidental deaths. In males aged 15-19, suicide rates peaked in 2001 before declining. Suicide by hanging is the most common method of suicide. Rates were higher in males and in 15- to 19-year-olds living in more deprived areas.

CONCLUSIONS

Suicide rates in adolescents are at their lowest since the early 1970s with no clear evidence that changes in coroners' practices underlie this trend.

Equating scores of the University of Pennsylvania Smell Identification Test and Sniffin' Sticks test in patients with Parkinson's disease

Background

Impaired olfaction is an important feature in Parkinson's disease (PD) and other neurological diseases. A variety of smell identification tests exist such as “Sniffin’ Sticks” and the University of Pennsylvania Smell Identification Test (UPSIT). An important part of research is being able to replicate findings or combining studies in a meta-analysis. This is difficult if olfaction has been measured using different metrics. We present conversion methods between the: UPSIT, Sniffin’ 16, and Brief-SIT (B-SIT); and Sniffin’ 12 and Sniffin’ 16 odour identification tests.

Methods

We used two incident cohorts of patients with PD who were tested with either the Sniffin’ 16 (n = 1131) or UPSIT (n = 980) and a validation dataset of 128 individuals who took both tests. We used the equipercentile and Item Response Theory (IRT) methods to equate the olfaction scales.

Results

The equipercentile conversion suggested some bias between UPSIT and Sniffin’ 16 tests across the two groups. The IRT method shows very good characteristics between the true and converted Sniffin’ 16 (delta mean = 0.14, median = 0) based on UPSIT. The equipercentile conversion between the Sniffin’ 12 and 16 item worked well (delta mean = 0.01, median = 0). The UPSIT to B-SIT conversion showed evidence of bias but amongst PD cases worked well (mean delta = −0.08, median = 0).

Conclusion

We have demonstrated that one can convert UPSIT to B-SIT or Sniffin’ 16, and Sniffin’ 12 to 16 scores in a valid way. This can facilitate direct comparison between tests aiding future collaborative analyses and evidence synthesis.

•

Need to harmonise olfaction tests (UPSIT and Sniffin’ Sticks) for meta-analysis.

•

Use of Item Response Theory and equipercentile methods to convert scores.

•

Validation shows high concordance and little bias between true and converted scores.

•

New age and gender corrected centiles for impaired olfaction from Sniffin’ scores.

Risk of reproductive complications following chlamydia testing: a population-based retrospective cohort study in Denmark

BACKGROUND

Uncertainty in the risk of reproductive complications (pelvic inflammatory disease, ectopic pregnancy, and tubal factor infertility) following chlamydia infection and repeat infection hampers the design of evidence-based chlamydia control programmes. We estimate the association between diagnosed chlamydia and episodes of hospital health care (inpatient, outpatient, and emergency department) for a reproductive complication.

METHODS

We constructed and analysed a retrospective population-based cohort of women aged 15-44 years from administrative records in Denmark (1995-2012). We used a subset of the national Danish Chlamydia Study. The master dataset contains all residents of Denmark (including Greenland) who had a positive chlamydia test recorded by a public health microbiology laboratory from Jan 1, 1992, to Nov 2, 2011. Individuals were randomly matched (by age and sex) to four individuals drawn from the population register (Danish Civil Registration System) who did not have a positive chlamydia test during this interval. The outcomes in the study were hospital episodes of health-care (inpatient, outpatient, and emergency department) with a diagnosis of pelvic inflammatory disease, ectopic pregnancy, or tubal factor infertility.

FINDINGS

The 516 720 women (103 344 positive, 182 879 negative, 230 497 never-tested) had a mean follow-up of 7·96 years. Compared with women with only negative tests, the risk of each complication was 30% higher in women with one or more positive tests (pelvic inflammatory disease, adjusted hazard ratio [AHR] 1·50 [95% CI 1·43-1·57]; ectopic pregnancy, AHR 1·31 [1·25-1·38]; tubal factor infertility, AHR 1·37 [1·24-1·52]) and 60% lower in women who were never-tested (pelvic inflammatory disease, AHR 0·33 [0·31-0·35]; ectopic pregnancy, AHR 0·42 [0·39-0·44]; tubal factor infertility AHR 0·29 [0·25-0·33]). A positive test had a minor absolute impact on health as the difference in the lifetime incidence of complications was small between women who tested positive and those who tested negative (pelvic inflammatory disease, 0·6%; ectopic pregnancy, 0·2%; tubal factor infertility, 0·1%). Repeat infections increased the risk of pelvic inflammatory disease by a further 20% (AHR 1·20, 95% CI 1·11-1·31).

INTERPRETATION

A single diagnosed chlamydia infection increased the risk of all complications and a repeat diagnosed infection further increased the risk of pelvic inflammatory disease. Therefore, control programmes must prevent first and repeat infections to improve women's reproductive health.

FUNDING

Unrestricted partial funding from Frederiksberg Kommune, Frederiksberg, Denmark. BD held an Medical Research Council Population Health Scientist Fellowship (G0902120). KT held an National Institute for Health Research Post-Doctoral Fellowship 2009-02-055.

Cause-Specific Mortality in HIV-Positive Patients Who Survived Ten Years after Starting Antiretroviral Therapy

OBJECTIVES

To estimate mortality rates and prognostic factors in HIV-positive patients who started combination antiretroviral therapy between 1996-1999 and survived for more than ten years.

METHODS

We used data from 18 European and North American HIV cohort studies contributing to the Antiretroviral Therapy Cohort Collaboration. We followed up patients from ten years after start of combination antiretroviral therapy. We estimated overall and cause-specific mortality rate ratios for age, sex, transmission through injection drug use, AIDS, CD4 count and HIV-1 RNA.

RESULTS

During 50,593 person years 656/13,011 (5%) patients died. Older age, male sex, injecting drug use transmission, AIDS, and low CD4 count and detectable viral replication ten years after starting combination antiretroviral therapy were associated with higher subsequent mortality. CD4 count at ART start did not predict mortality in models adjusted for patient characteristics ten years after start of antiretroviral therapy. The most frequent causes of death (among 340 classified) were non-AIDS cancer, AIDS, cardiovascular, and liver-related disease. Older age was strongly associated with cardiovascular mortality, injecting drug use transmission with non-AIDS infection and liver-related mortality, and low CD4 and detectable viral replication ten years after starting antiretroviral therapy with AIDS mortality. Five-year mortality risk was <5% in 60% of all patients, and in 30% of those aged over 60 years.

CONCLUSIONS

Viral replication, lower CD4 count, prior AIDS, and transmission via injecting drug use continue to predict higher all-cause and AIDS-related mortality in patients treated with combination antiretroviral therapy for over a decade. Deaths from AIDS and non-AIDS infection are less frequent than deaths from other non-AIDS causes.

Impact of Opioid Substitution Therapy on Antiretroviral Therapy Outcomes: A Systematic Review and Meta-Analysis

This meta-analysis provides strong evidence that opioid substitution therapy improves several key outcomes of the HIV care continuum among people who inject drugs, including recruitment onto antiretroviral therapy, retention in care, adherence, and viral suppression.

Background. Human immunodeficiency virus (HIV)–infected people who inject drugs (PWID) frequently encounter barriers accessing and remaining on antiretroviral therapy (ART). Some studies have suggested that opioid substitution therapy (OST) could facilitate PWID's engagement with HIV services. We conducted a systematic review and meta-analysis to evaluate the impact of concurrent OST use on ART-related outcomes among HIV-infected PWID.

Methods. We searched Medline, PsycInfo, Embase, Global Health, Cochrane, Web of Science, and Social Policy and Practice databases for studies between 1996 to November 2014 documenting the impact of OST, compared to no OST, on ART outcomes. Outcomes considered were coverage and recruitment onto ART, adherence, viral suppression, attrition from ART, and mortality. Meta-analyses were conducted using random-effects modeling, and heterogeneity assessed using Cochran Q test and I² statistic.

Results. We identified 4685 articles, and 32 studies conducted in North America, Europe, Indonesia, and China were included. OST was associated with a 69% increase in recruitment onto ART (hazard ratio [HR], 1.69; 95% confidence interval [CI], 1.32–2.15), a 54% increase in ART coverage (odds ratio [OR], 1.54; 95% CI, 1.17–2.03), a 2-fold increase in adherence (OR, 2.14; 95% CI, 1.41–3.26), and a 23% decrease in the odds of attrition (OR, 0.77; 95% CI, .63–.95). OST was associated with a 45% increase in odds of viral suppression (OR, 1.45; 95% CI, 1.21–1.73), but there was limited evidence from 6 studies for OST decreasing mortality for PWID on ART (HR, 0.91; 95% CI, .65–1.25).

Conclusions. These findings support the use of OST, and its integration with HIV services, to improve the HIV treatment and care continuum among HIV-infected PWID.

Parkinson's Disease Subtypes in the Oxford Parkinson Disease Centre (OPDC) Discovery Cohort

Background: Within Parkinson’s there is a spectrum of clinical features at presentation which may represent sub-types of the disease. However there is no widely accepted consensus of how best to group patients.

Objective: Use a data-driven approach to unravel any heterogeneity in the Parkinson’s phenotype in a well-characterised, population-based incidence cohort.

Methods: 769 consecutive patients, with mean disease duration of 1.3 years, were assessed using a broad range of motor, cognitive and non-motor metrics. Multiple imputation was carried out using the chained equations approach to deal with missing data. We used an exploratory and then a confirmatory factor analysis to determine suitable domains to include within our cluster analysis. K-means cluster analysis of the factor scores and all the variables not loading into a factor was used to determine phenotypic subgroups.

Results: Our factor analysis found three important factors that were characterised by: psychological well-being features; non-tremor motor features, such as posture and rigidity; and cognitive features. Our subsequent five cluster model identified groups characterised by (1) mild motor and non-motor disease (25.4%), (2) poor posture and cognition (23.3%), (3) severe tremor (20.8%), (4) poor psychological well-being, RBD and sleep (18.9%), and (5) severe motor and non-motor disease with poor psychological well-being (11.7%).

Conclusion: Our approach identified several Parkinson’s phenotypic sub-groups driven by largely dopaminergic-resistant features (RBD, impaired cognition and posture, poor psychological well-being) that, in addition to dopaminergic-responsive motor features may be important for studying the aetiology, progression, and medication response of early Parkinson’s.

Validation of conversion between mini-mental state examination and montreal cognitive assessment

INTRODUCTION

Harmonizing data across cohorts is important for validating findings or combining data in meta-analyses. We replicate and validate a previous conversion of MoCA to MMSE in PD.

METHODS

We used five studies with 1,161 PD individuals and 2,091 observations measured with both the MoCA and MMSE. We compared a previously published conversion table using equipercentile equating with log-linear smoothing to our internally derived scores.

RESULTS

Both conversions found good agreement within and across the studies when comparing true and converted MMSE (mean difference: 0.05; standard deviation: 1.84; median difference: 0; interquartile range: -1 to 1, using internal conversion).

CONCLUSIONS

These results show that one can get a reliable and valid conversion between two commonly used measures of cognition in PD studies. These approaches need to be applied to other scales and domains to enable large-scale collaborative analyses across multiple PD cohorts.

Joint longitudinal hurdle and time-to-event models: an application related to viral load and duration of the first treatment regimen in patients with HIV initiating therapy

Shared parameter joint models provide a framework under which a longitudinal response and a time to event can be modelled simultaneously. A common assumption in shared parameter joint models has been to assume that the longitudinal response is normally distributed. In this paper, we instead propose a joint model that incorporates a two-part 'hurdle' model for the longitudinal response, motivated in part by longitudinal response data that is subject to a detection limit. The first part of the hurdle model estimates the probability that the longitudinal response is observed above the detection limit, whilst the second part of the hurdle model estimates the mean of the response conditional on having exceeded the detection limit. The time-to-event outcome is modelled using a parametric proportional hazards model, assuming a Weibull baseline hazard. We propose a novel association structure whereby the current hazard of the event is assumed to be associated with the current combined (expected) outcome from the two parts of the hurdle model. We estimate our joint model under a Bayesian framework and provide code for fitting the model using the Bayesian software Stan. We use our model to estimate the association between HIV RNA viral load, which is subject to a lower detection limit, and the hazard of stopping or modifying treatment in patients with HIV initiating antiretroviral therapy. Copyright © 2016 John Wiley & Sons, Ltd.

Mortality According to CD4 Count at Start of Combination Antiretroviral Therapy Among HIV-infected Patients Followed for up to 15 Years After Start of Treatment: Collaborative Cohort Study

The strong association of CD4 count at start of combination therapy with subsequent survival in HIV-infected patients diminished during the first 5 years of treatment. After 5 years, lower baseline CD4 counts were not associated with higher mortality.

Background. CD4 count at start of combination antiretroviral therapy (ART) is strongly associated with short-term survival, but its association with longer-term survival is less well characterized.

Methods. We estimated mortality rates (MRs) by time since start of ART (<0.5, 0.5–0.9, 1–2.9, 3–4.9, 5–9.9, and ≥10 years) among patients from 18 European and North American cohorts who started ART during 1996–2001. Piecewise exponential models stratified by cohort were used to estimate crude and adjusted (for sex, age, transmission risk, period of starting ART [1996–1997, 1998–1999, 2000–2001], and AIDS and human immunodeficiency virus type 1 RNA at baseline) mortality rate ratios (MRRs) by CD4 count at start of ART (0–49, 50–99, 100–199, 200–349, 350–499, ≥500 cells/µL) overall and separately according to time since start of ART.

Results. A total of 6344 of 37 496 patients died during 359 219 years of follow-up. The MR per 1000 person-years was 32.8 (95% confidence interval [CI], 30.2–35.5) during the first 6 months, declining to 16.0 (95% CI, 15.4–16.8) during 5–9.9 years and 14.2 (95% CI, 13.3–15.1) after 10 years’ duration of ART. During the first year of ART, there was a strong inverse association of CD4 count at start of ART with mortality. This diminished over the next 4 years. The adjusted MRR per CD4 group was 0.97 (95% CI, .94–1.00; P = .054) and 1.02 (95% CI, .98–1.07; P = .32) among patients followed for 5–9.9 and ≥10 years, respectively.

Conclusions. After surviving 5 years of ART, the mortality of patients who started ART with low baseline CD4 count converged with mortality of patients with intermediate and high baseline CD4 counts.

Immunologic response in treatment-naïve HIV-2-infected patients: the IeDEA West Africa cohort

INTRODUCTION

Response to antiretroviral therapy (ART) among individuals infected with HIV-2 is poorly described. We compared the immunological response among patients treated with three nucleoside reverse-transcriptase inhibitors (NRTIs) to boosted protease inhibitor (PI) and unboosted PI-based regimens in West Africa.

METHODS

This prospective cohort study enrolled treatment-naïve HIV-2-infected patients within the International Epidemiological Databases to Evaluate AIDS collaboration in West Africa. We used mixed models to compare the CD4 count response to treatment over 12 months between regimens.

RESULTS

Of 422 HIV-2-infected patients, 285 (67.5%) were treated with a boosted PI-based regimen, 104 (24.6%) with an unboosted PI-based regimen and 33 (7.8%) with three NRTIs. Treatment groups were comparable with regard to gender (54.5% female) and median age at ART initiation (45.3 years; interquartile range 38.3 to 51.8). Treatment groups differed by clinical stage (21.2%, 16.8% and 17.3% at CDC Stage C or World Health Organization Stage IV for the triple NRTI, boosted PI and unboosted PI groups, respectively, p=0.02), median length of follow-up (12.9, 17.7 and 44.0 months for the triple NRTI, the boosted PI and the unboosted PI groups, respectively, p<0.001) and baseline median CD4 count (192, 173 and 129 cells/µl in the triple NRTI, the boosted PI and the unboosted PI-based regimen groups, respectively, p=0.003). CD4 count recovery at 12 months was higher for patients treated with boosted PI-based regimens than those treated with three NRTIs or with unboosted PI-based regimens (191 cells/µl, 95% CI 142 to 241; 110 cells/µl, 95% CI 29 to 192; 133 cells/µl, 95% CI 80 to 186, respectively, p=0.004).

CONCLUSIONS

In this observational study using African data, boosted PI-containing regimens had better immunological response compared to triple NRTI combinations and unboosted PI-based regimens at 12 months. A randomized clinical trial is still required to determine the best initial regimen for treating HIV-2 infected patients.

Global and Regional Estimates of Prevalent and Incident Herpes Simplex Virus Type 1 Infections in 2012

Background

Herpes simplex virus type 1 (HSV-1) commonly causes orolabial ulcers, while HSV-2 commonly causes genital ulcers. However, HSV-1 is an increasing cause of genital infection. Previously, the World Health Organization estimated the global burden of HSV-2 for 2003 and for 2012. The global burden of HSV-1 has not been estimated.

Methods

We fitted a constant-incidence model to pooled HSV-1 prevalence data from literature searches for 6 World Health Organization regions and used 2012 population data to derive global numbers of 0-49-year-olds with prevalent and incident HSV-1 infection. To estimate genital HSV-1, we applied values for the proportion of incident infections that are genital.

Findings

We estimated that 3709 million people (range: 3440–3878 million) aged 0–49 years had prevalent HSV-1 infection in 2012 (67%), with highest prevalence in Africa, South-East Asia and Western Pacific. Assuming 50% of incident infections among 15-49-year-olds are genital, an estimated 140 million (range: 67–212 million) people had prevalent genital HSV-1 infection, most of which occurred in the Americas, Europe and Western Pacific.

Conclusions

The global burden of HSV-1 infection is huge. Genital HSV-1 burden can be substantial but varies widely by region. Future control efforts, including development of HSV vaccines, should consider the epidemiology of HSV-1 in addition to HSV-2, and especially the relative contribution of HSV-1 to genital infection.

Time trends for risk of severe age-related diseases in individuals with and without HIV infection in Denmark: a nationwide population-based cohort study

BACKGROUND

Whether the reported high risk of age-related diseases in HIV-infected people is caused by biological ageing or HIV-associated risk factors such as chronic immune activation and low-grade inflammation is unknown. We assessed time trends in age-standardised and relative risks of nine serious age-related diseases in a nationwide cohort study of HIV-infected individuals and population controls.

METHODS

We identified all HIV-infected individuals in the Danish HIV Cohort Study who had received HIV care in Denmark between Jan 1, 1995, and June 1, 2014. Population controls were identified from the Danish Civil Registration System and individually matched in a ratio of nine to one to the HIV-infected individuals for year of birth, sex, and date of study inclusion. Individuals were included in the study if they had a Danish personal identification number, were aged 16 years or older, and were living in Denmark at the time of study inclusion. Data for study outcomes were obtained from the Danish National Hospital Registry and the Danish National Registry of Causes of Death and were cardiovascular diseases (myocardial infarction and stroke), cancers (virus associated, smoking related, and other), severe neurocognitive disease, chronic kidney disease, chronic liver disease, and osteoporotic fractures. We calculated excess and age-standardised incidence rates and adjusted incidence rate ratios of outcomes for time after HIV diagnosis, highly active antiretroviral therapy (ART) initiation, and calendar time. The regression analyses were adjusted for age, sex, calendar time, and origin.

FINDINGS

We identified 5897 HIV-infected individuals and 53,073 population controls; median age was 36·8 years (IQR 30·6-44·4), and 76% were men in both cohorts. Dependent on disease, the HIV cohort had 55,050-57,631 person-years of follow-up and the population controls had 638,204-659,237 person-years of follow-up. Compared with the population controls, people with HIV had high excess and relative risk of all age-related diseases except other cancers. Overall, the age-standardised and relative risks of cardiovascular diseases, cancers, and severe neurocognitive disease did not increase substantially with time after HIV diagnosis or ART initiation. Except for chronic kidney diseases, the age-standardised and relative risks of age-related diseases did not increase with calendar time.

INTERPRETATIONS

Severe age-related diseases are highly prevalent in people with HIV, and continued attention and strategies for risk reduction are needed. The findings from our study do not suggest that accelerated ageing is a major problem in the HIV-infected population.

FUNDING

Preben og Anna Simonsens Fond, Novo Nordisk Foundation, Danish AIDS Foundation, Augustinus Foundation, and Odense University Hospitals Frie Fonds Midler.

Bariatric surgery in morbidly obese insulin resistant humans normalises insulin signalling but not insulin-stimulated glucose disposal

Aims

Weight-loss after bariatric surgery improves insulin sensitivity, but the underlying molecular mechanism is not clear. To ascertain the effect of bariatric surgery on insulin signalling, we examined glucose disposal and Akt activation in morbidly obese volunteers before and after Roux-en-Y gastric bypass surgery (RYGB), and compared this to lean volunteers.

Materials and Methods

The hyperinsulinaemic euglycaemic clamp, at five infusion rates, was used to determine glucose disposal rates (GDR) in eight morbidly obese (body mass index, BMI=47.3±2.2 kg/m²) patients, before and after RYGB, and in eight lean volunteers (BMI=20.7±0.7 kg/m²). Biopsies of brachioradialis muscle, taken at fasting and insulin concentrations that induced half-maximal (GDR₅₀) and maximal (GDR₁₀₀) GDR in each subject, were used to examine the phosphorylation of Akt-Thr308, Akt-473, and pras40, in vivo biomarkers for Akt activity.

Results

Pre-operatively, insulin-stimulated GDR was lower in the obese compared to the lean individuals (P<0.001). Weight-loss of 29.9±4 kg after surgery significantly improved GDR₅₀ (P=0.004) but not GDR₁₀₀ (P=0.3). These subjects still remained significantly more insulin resistant than the lean individuals (p<0.001). Weight loss increased insulin-stimulated skeletal muscle Akt-Thr308 and Akt-Ser473 phosphorylation, P=0.02 and P=0.03 respectively (MANCOVA), and Akt activity towards the substrate PRAS40 (P=0.003, MANCOVA), and in contrast to GDR, were fully normalised after the surgery (obese vs lean, P=0.6, P=0.35, P=0.46, respectively).

Conclusions

Our data show that although Akt activity substantially improved after surgery, it did not lead to a full restoration of insulin-stimulated glucose disposal. This suggests that a major defect downstream of, or parallel to, Akt signalling remains after significant weight-loss.