In a recent study published in the journal Dr eClinical MedicineA group of researchers evaluated the cost-effectiveness and health impact of implementing a combined genomic screening program for hereditary breast and ovarian cancer (HBOC), Lynch syndrome (LS), and familial hypercholesterolemia (FH) in young Australian adults, at a national level. Public health system.
Population genomic screening offers a significant public health opportunity for early detection and prevention of cancer and heart disease from high-risk genetic conditions such as HBOC, LS, and FH.
An estimated 1.3% of people carry pathogenic variants associated with this condition, which are excellent candidates for screening because of their common and effective intervention. Current detection is limited due to restrictive testing criteria, missing many who may benefit from early risk-reduction strategies such as surgery or drugs. Further research is needed to optimize and fully understand the implications of comprehensive genomic screening for high-risk conditions, addressing its feasibility, ethical considerations, and equitable access within public health systems.
About the study
The researchers developed three decision-analysis models with Markov elements to investigate the outcomes associated with pathogenic variants (PVs) for HBOC (BRCA)1 and BRCA2 genes in breast cancer; LS in MutL Homolog (MLH)1 and MutS Homolog (MSH)2 genes for colorectal and endometrial cancer; and FH in LDLR (low-density lipoprotein receptor), apolipoprotein B (APOB), and proprotein convertase subtilisin/kexin type 9 (PCSK9) genes for coronary heart disease (CHD).
Partners and localizers of BRCA2 (PALB2) and MSH6 were excluded due to insufficient data.
Each model began with discrete state analysis, progressing to integrated multistate transition models for larger cohorts, incorporating health state transitions based on probabilities.
Two strategies were evaluated: existing Australian criteria-based testing (Strategy 1) and a proposed universal genomic screening (Strategy 2) with an ideal detection rate, 50% uptake and assuming perfect test sensitivity among Australians aged 18–40, modeled First year at the beginning.
A life-table approach evaluates morbidity and mortality among identified PV carriers over a lifetime by incorporating genetic counseling, standard risk management, and intervention costs.
Following Australian guidelines, the risk is based on published data and models reflecting an incremental cost-effectiveness ratio (ICER) targeting an AU$50,000/QALY threshold of life years and cancer/CHD events prevented by screening.
The models included Australian data for the 18–40 population with 50% screening uptake expected from 2023. Strategies have addressed cancer surveillance and preventive surgery for HBOC, intensive surveillance for LS, and statins with varying adherence rates for FH.
Utility scores and associated costs were sourced from existing studies. Costs for Strategy 1 in Australia mirrored current genetic testing rates, with Strategy 2 costing AU$200 per test.
Viability was tested through scenario and sensitivity analysis, which included Monte Carlo simulations to determine factors affecting cost-effectiveness. Analyzes were from a healthcare perspective with a 5% annual discount.
Results of the study
The researchers compared the current practice of criteria-based genetic testing with an alternative strategy of widespread population genomic screening for three high-risk health conditions.
The results were striking: the screening approach was estimated to avoid numerous health events over the lifetime of the population – 2,612 cancer cases, 542 non-fatal CHD events and 4,047 cancer or CHD deaths.
Translated on a per-100,000-person basis, this means 63 fewer cancer cases, 31 fewer CHD cases and 97 fewer deaths. In terms of life years, genomic screening may gain an additional 20,553 years of life and 31,094 QALYs compared to the status quo, which equates to 494 more life years and 747 more QALYs per 100,000 individuals screened.
In a financial overview, introducing genomic screening at a 50% participation rate would cost Australia AU$832 million upfront on top of current genetic testing costs, plus AU$282 million in continuing care for identified pathogenic variant carriers.
The strategy’s preventive benefits are expected to outweigh its costs, potentially saving more than AU$394 million in reduced costs from chronic disease and mortality, resulting in a net screening cost of AU$825.54 million. The procedure is expected to remain cost-effective despite an increase in test costs of AU$325.
Scenario analyzes explored the cost-effectiveness of expanding population genomic screening to different age ranges. Extending screening to ages 18–50 or 25–50 years was cost-effective, with ICERs significantly below the payment threshold.
However, the core 18–40 age group proved to be the most cost-efficient strategy, providing the best balance of costs and QALYs gained. When evaluating individual conditions, screening for FH was economically justified, while screening for HBOC or LS alone was not within the same population structure.
From a broader societal perspective, genomic screening was cost-effective at AU$200 per test, considering productivity losses. Even at an increased cost of AU$325 per test, screening remained within acceptable cost-effectiveness margins.
However, the increase to AU$500 per test breached the cost-effectiveness threshold. Furthermore, adjusting the base-case discount rate from 5% to 3% dramatically reduced the ICER, showing a more favorable cost-benefit scenario often adopted outside of Australia.
Sensitivity analyzes assessed the robustness of the base-case model for combined genomic screening of HBCO, LS, and FH at AU$200 per test. One-way sensitivity analysis confirmed that all variations in input parameters resulted in ICERs below the AU$50,000/QALY threshold. Probabilistic sensitivity analysis further supports the cost-effectiveness of screening, with simulations showing that the method will be cost-effective in 70% of cases, cost-saving in 25% of cases, and not cost-effective in only 5% of cases.