A quantitative weight of evidence assessment of Hill's guidelines for causal inference for cosmetic talc as a cause of mesothelioma

Can Weight of Evidence, Quantitative Bias, and Bounding Methods Evaluate Robustness of Real-world Evidence for Regulator and Health Technology Assessment Decisions on Medical Interventions?

PURPOSE

High-quality evidence is crucial for health care intervention decision-making. These decisions frequently use nonrandomized data, which can be more vulnerable to biases than randomized trials. Accordingly, methods to quantify biases and weigh available evidence could elucidate the robustness of findings, giving regulators more confidence in making approval and reimbursement decisions.

METHODS

We conducted an integrative literature review to identify methods for determining probability of causation, evaluating weight of evidence, and conducting quantitative bias analysis as related to health care interventions. Eligible studies were published from 2012 to 2021, applicable to pharmacoepidemiology, and presented a method that met our objective.

FINDINGS

Twenty-two eligible studies were classified into 4 categories: (1) quantitative bias analysis; (2) weight of evidence methods; (3) Bayesian networks; and (4) miscellaneous. All of the methods have strengths, limitations, and situations in which they are more well suited than others. Some methods seem to lend themselves more to applications of health care evidence on medical interventions than others.

IMPLICATIONS

To provide robust evidence for and improve confidence in regulatory or reimbursement decisions, we recommend applying multiple methods to triangulate associations of medical interventions, accounting for biases in different ways. This approach could lead to well-defined robustness assessments of study findings and appropriate science-driven decisions by regulators and payers for public health.

An updated review of diffuse mesothelioma of the pleura - A sentinel health event of potential elongate mineral particle pathogenicity

There are approximately 400 inorganic minerals in the Earth's crust, some of which can be encountered as elongate mineral particles [EMPs] with dimensional characteristics similar to the six minerals known as asbestos and other asbestiform amphiboles with established human pathogenicity. In addition, the rapidly developing field of nanotechnology is producing an ever-increasing array of high aspect ratio engineered nanomaterials [HARNs] with physical dimensions and biodurability similar to the asbestos fiber types with recognized pathogenic potential. Many of these non-asbestos/non-asbestiform EMPs and HARNs with the potential for aerosolization into the breathing zones of workers and in individuals in non-occupational environments have not yet been thoroughly studied with respect to their potential human pathogenicity, a fact which obviously poses concerns for both occupational health and public health professionals. On the basis of dose-response considerations it seems reasonable to infer that if any of these non-regulated EMPs or HARNs actually are pathogenic, then those mineral fiber exposure-induced disorders associated with the lowest cumulative exposure doses of the commercial amphibole types of asbestos, that is, diffuse mesothelioma of the pleura, and its non-malignant correlate of benign parietal pleural plaques, are those which are most likely to occur following inhalational exposures to any of the non-regulated EMPs and HARNs. Because of that observation, this paper reviews certain aspects of diffuse mesothelioma, including a summary of recent changes in the nomenclature of diffuse mesothelioma of the pleura; of both the descriptive and the analytical epidemiology of the disease; of the etiologies of mesothelioma, both "exposure" related and endogenous in nature; and of the asbestos population attributable fraction for diffuse mesotheliomas in the USA, both historically and in the future.

Updated Italian cohort data continues to confirm lack of mesothelioma risk in pooled cohort of international cosmetic talc miners and millers

OBJECTIVES

To assess potential mesothelioma risk following inhalation of cosmetic talc, we updated previous iterations of a pooled cohort analysis, post-study statistical power analysis, and confidence interval function analysis for a pooled cohort of international cosmetic talc miners/millers given new Italian cohort data.

METHODS

Five cohorts of cosmetic talc miners/millers were pooled. Expected numbers of mesotheliomas for each cohort were reported by the original authors. We based our post-study statistical power analysis on an a priori one-sided significance level of 0.05, and exact Poisson and approximate distribution probabilities. To evaluate the confidence interval function for the observed pooled mesothelioma standardized mortality ratios (SMRs), we calculated the probability for the upper 100(1-2α)% confidence limit that equals various SMRs of interest.

RESULTS

The pooled cohorts generated a total observation time of 135,524.38 person-years. Overall, 4.14 mesotheliomas were expected (mid-value estimate), though only one case of mesothelioma has been confirmed in the pooled cohort to date. We calculated 71% and 87% post-study power to detect a 2.5-fold or greater and a 3.0-fold or greater increase in mesothelioma, respectively. Our complimentary confidence interval function analysis demonstrated that the probability that the true mesothelioma SMR for the pooled cohort was at or above 2.0 or at or above 3.0 was 0.00235 and 0.00005, respectively.

CONCLUSIONS

Based on the updated results of our various analyses, the current epidemiological evidence from cosmetic talc miner/miller cohort studies continues to not support the hypothesis that the inhalation of cosmetic talc is associated with an increased risk of mesothelioma.

Standardized Incidence Ratio and Standardized Mortality Ratio of Malignant Mesothelioma in a Worker Cohort Using Employment Insurance Database in Korea

Malignant mesothelioma is one of the appropriate indicators for assessing the carcinogenic effects of asbestos. This study compared the risk ratio of mesothelioma according to the industry in the worker cohort. A cohort was constructed using the Korean employment insurance system during 1995–2017, enrolling 13,285,895 men and 10,452,705 women. The standardized mortality ratio (SMR) and standardized incidence ratio (SIR) were calculated using the indirect standardization method. There were 641 malignant mesotheliomas that occurred; the SIR was significantly higher than the general population (men 1.36, 95% confidence interval (CI) 1.24–1.48, women 1.44, 95% CI: 1.23–1.7). More than half (52.8%) of malignant mesothelioma cases occurred in the manufacturing (n = 240, 38.6%, SIR: men, 1.72, 95% CI: 1.37–2.15, women, 3.31, 95% CI: 1.71–5.79) and construction industries (n = 88, 14.2%, SIR: men, 1.54 95% CI: 1.33–1.78, women, 1.62 95% CI: 1.25–2.11). The accommodation and food service (men, 2.56 95% CI: 1.28–4.58, women 1.35, 95% CI: 0.65–2.48) and real estate (men 1.34, 95% CI: 0.98–1.83, women 1.95, 95% CI: 0.78–4.02) also showed a high SIR, indicating the risk of asbestos-containing materials in old buildings. The incidence of malignant mesothelioma is likely to increase in the future, given the long latency of this disease. Moreover, long-term follow-up studies will be needed.