Cancer risk in people living with HIV and solid organ transplant recipients: a systematic review and meta-analysis.

BACKGROUND: Systematic evaluations of cancer risk in people living with HIV or AIDS (PLHIV) and solid organ transplant recipients provide unique insights into the role of the immune system in cancer development. In this systematic review and meta-analysis, we expand previous analyses of cancer risk for these two immunocompromised populations. METHODS: We considered studies published in English and listed on PubMed or Embase up to July 1, 2022. Studies were eligible for inclusion if they used population-based registries and compared cancer incidence in PLHIV or solid organ transplant recipients with the general population in the same geographical area. We extracted the number of observed site-specific cancers and expected cases and calculated meta-standardised incidence ratios for cancer within PLHIV and solid organ transplant recipients. In solid organ transplant recipients meta-standardised incidence ratios were compared by organ type. This project is registered on PROSPERO, CRD42022366679. FINDINGS: 46 studies in PLHIV and 67 in solid organ transplant recipients were included in the analysis. Meta-standardised incidence ratios for cancers associated with human papillomavirus were increased in both populations; the highest meta-standardised incidence ratio in PLHIV was anal cancer (37·28 [95% CI 23·65-58·75], I2=97·4%), and in solid organ transplant recipients was cutaneous squamous cell carcinoma (45·87 [31·70-66·38], I2=99·0%). Meta-standardised incidence ratios were significantly increased for most non-HPV viral-infection-related cancers in both populations; the highest standard incidence ratios were for Kaposi sarcoma (PLHIV: 801·52 [95% CI 200·25-3208·13], I2=100·0%; solid organ transplant recipients: 47·31 [23·09-96·95], I2=87·7%) and non-Hodgkin lymphoma (32·53 [19·64-53·87], I2=99·8%; 10·24 [8·48-12·35], I2=94·9%). Eight types of cancer with no known viral cause showed an increased risk in solid organ transplant recipients only; no cancer type showed increased risk in PLHIV only. INTERPRETATION: Cancer risk was increased for a range of infection-related cancers in both PLHIV and solid organ transplant recipients, but divergent results in these and other cancers have emerged. The cancer risk patterns probably reflect variances in the degree of impaired immunity, exposure to carcinogenic viruses, and perhaps exposure to carcinogenic immunosuppressive agents. FUNDING: US National Cancer Institute, National Institutes of Health.

Estimating the impact of bias in causal epidemiological studies: the case of health outcomes following assisted reproduction.

Researchers interested in causal questions must deal with two sources of error: random error (random deviation from the true mean value of a distribution), and bias (systematic deviance from the true mean value due to extraneous factors). For some causal questions, randomization is not feasible, and observational studies are necessary. Bias poses a substantial threat to the validity of observational research and can have important consequences for health policy developed from the findings. The current piece describes bias and its sources, outlines proposed methods to estimate its impacts in an observational study, and demonstrates how these methods may be used to inform debate on the causal relationship between medically assisted reproduction (MAR) and health outcomes, using cancer as an example. In doing so, we aim to enlighten researchers who work with observational data, especially regarding the health effects of MAR and infertility, on the pitfalls of bias, and how to address them. We hope that, in combination with the provided example, we can convince readers that estimating the impact of bias in causal epidemiologic research is not only important but necessary to inform the development of robust health policy and clinical practice recommendations.

Relative survival in patients with cancer and kidney failure.

BACKGROUND AND HYPOTHESIS: The population with kidney failure is at increased risk of cancer and associated mortality. Relative survival can provide insight into the excess mortality, directly or indirectly, attributed to cancer in the population with kidney failure. METHODS: We estimated relative survival for people all ages receiving dialysis (n = 4089) and kidney transplant recipients (n = 3253) with de novo cancer, and for the general population with cancer in Australia and New Zealand (n = 3 043 166) over the years 1980-2019. The entire general population was the reference group for background mortality, adjusted for sex, age, calendar year and country. We used Poisson regression to quantify excess mortality ratios. RESULTS: Five-year relative survival for all-site cancer was markedly lower than the general population for people receiving dialysis (0.25, 95%CI:0.23-0.26) and kidney transplant recipients (0.55, 95%CI:0.53-0.57). In dialysis, excess mortality was more than double (2.16, 95%CI:2.08-2.25) that of the general population with cancer and for kidney transplant recipients 1.34 higher (95%CI:1.27-2.41). There was no difference in excess mortality from lung cancer between people with kidney failure and the general population with cancer. Comparatively, there was a significant survival deficit for people with kidney failure, compared to the general population with cancer, for melanoma, breast cancer and prostate cancers. CONCLUSION: Decreased cancer survival in kidney failure may reflect differences in multi-morbidity burden, reduced access to treatment, or greater harm from or reduced efficacy of treatments. Our findings support research aimed at investigating these hypotheses.

The Medicines Intelligence Data Platform: A Population-Based Data Resource From New South Wales, Australia.

BACKGROUND: The Medicines Intelligence (MedIntel) Data Platform is an anonymised linked data resource designed to generate real-world evidence on prescribed medicine use, effectiveness, safety, costs and cost-effectiveness in Australia. RESULTS: The platform comprises Medicare-eligible people who are ≥18 years and residing in New South Wales (NSW), Australia, any time during 2005-2020, with linked administrative data on dispensed prescription medicines (Pharmaceutical Benefits Scheme), health service use (Medicare Benefits Schedule), emergency department visits (NSW Emergency Department Data Collection), hospitalisations (NSW Admitted Patient Data Collection) plus death (National Death Index) and cancer registrations (NSW Cancer Registry). Data are currently available to 2022, with approval to update the cohort and data collections annually. The platform includes 7.4 million unique people across all years, covering 36.9% of the Australian adult population; the overall population increased from 4.8 M in 2005 to 6.0 M in 2020. As of 1 January 2019 (the last pre-pandemic year), the cohort had a mean age of 48.7 years (51.1% female), with most people (4.4 M, 74.7%) residing in a major city. In 2019, 4.4 M people (73.3%) were dispensed a medicine, 1.2 M (20.5%) were hospitalised, 5.3 M (89.4%) had a GP or specialist appointment, and 54 003 people died. Anti-infectives were the most prevalent medicines dispensed to the cohort in 2019 (43.1%), followed by nervous system (32.2%) and cardiovascular system medicines (30.2%). CONCLUSION: The MedIntel Data Platform creates opportunities for national and international research collaborations and enables us to address contemporary clinically- and policy-relevant research questions about quality use of medicines and health outcomes in Australia and globally.

Cohort profile: understanding health service system needs for people with intellectual disability using linked data in New South Wales, Australia.

This cohort profile describes one of the largest linked datasets in the world concerning the health of people with intellectual disability. The cohort comprises a retrospective group of 100,089 individuals with intellectual disability who received disability and/or health services in New South Wales, Australia. Of these participants, 34% were female, with a median age at cohort entry of 3 years (interquartile range, 0 to 19 years). A separate comparator cohort included 455,677 individuals, matched by 5-year age group, sex, and residential postcode at a 5:1 ratio. Initial results indicate that between 2001 and 2018, people with intellectual disability experienced more than double the rate of hospitalisations (538 versus 235 per 1000 person-years), as well as markedly higher rates of emergency department presentations (707 versus 379 per 1000 person-years) and use of ambulatory mental health services (1012 versus 157 per 1000 person-years), relative to the comparator cohort. The largest disparities in hospital admissions were for mental disorders, dialysis, and diseases of the nervous system and sense organs. Furthermore, individuals with intellectual disability had more than double the rate of dispensed medications found in the comparator cohort. Of these medications, 46.6% were for the treatment of nervous system conditions, as opposed to 24.7% for the comparator cohort. The mean age at death was 52 years (standard deviation [SD], 19 years) for people with intellectual disability and 64 years (SD, 22 years) for the comparator participants.

Transmission and Non-transmission of Melanoma From Deceased Solid Organ Donors to Transplant Recipients: Risks and Missed Opportunities.

BACKGROUND: Biovigilance concerns are in tension with the need to increase organ donation. Cancer transmission risk from donor to recipient may be overestimated, as non-transmission events are rarely reported. We sought to estimate melanoma transmission risk in deceased organ donation and identify missed opportunities for donation in an Australian cohort with high melanoma prevalence. METHODS: We used a population-based approach and linked deceased organ donors, transplant recipients, and potential donors forgone, 2010-2018, with the Central Cancer Registry (CCR), 1976-2018. We identified melanomas using ICD-O-3 classification, assessed the probability of transmission, and compared suspected melanoma history in potential donors forgone with melanoma notifications in the CCR. RESULTS: There were 9 of 993 donors with melanoma in CCR; 4 in situ low-risk and 5 invasive high-to-unacceptable risk. Four were unrecognized before donation. Of 16 transplant recipients at risk, we found 0 of 14 transmission events (2 recipients had insufficient follow-up). Of 35 of 3588 potential donors forgone for melanoma risk alone, 17 were otherwise suitable for donation; 6 of 35 had no melanoma in CCR, 2 of 35 had in situ melanomas and 9 of 35 had thin invasive melanomas (localized, ≤0.8 mm thickness). CONCLUSIONS: Our findings contribute to current evidence that suggests donors with melanomas of low metastatic potential may provide an opportunity to safely increase organ donation and so access to transplantation.