Toward Kidney-Specific Causality Assessment Tool

Abstract

Purpose: Current nonspecific causality assessment tools lack the assessment of drug-induced acute kidney injury (DIAKI). We recently published an editorial letter for developing a specific causality assessment tool for DIAKI. The purpose of the present review was to suggest the possible required parameters and outline the path to developing a kidney-specific causality assessment tool (KSCAT).

Methods: A stepwise approach for developing a KSCAT is important as this will be first version of this new tool. Thus, as a first step, we performed a screening of previously published articles on nonspecific and liver-specific causality assessment tools to define possible parameters. The suggested parameters for KSCAT fall into 3 categories: (1) drug-related; (2) kidney-related; and (3) terminology. A tri-polar method was then created that consists of definitive adverse drug reactions (ADRS), terminology, and without ADRS to suggest that the new KSCAT be efficient, specific, user friendly, and less time-consuming. Finally, a pyramid model is suggested to offer the perspectives of experts in the fields of pharmacovigilance, pharmacoepidemiology, and nephrology, as well as decision makers, while developing a KSCAT.

Findings: Causality assessment tools, either nonspecific or organ-specific, fall into 3 categories: (1) expert judgment; (2) algorithms; and (3) probabilistic methods. None of the current causality assessment tools is sufficient for assessing the causality of kidney-related ADRs and for screening the expanded definition of ADR included in European Union Directive 2010/84/EU.

Implications: The causal relationship between drug(s) and DIAKI may be difficult and may not be assessed appropriately with the use of nonspecific tools or approaches. The aim of this article was to reiterate the need for KSCAT development and to propose the associated steps by stating the main principles: namely, the definition of ADR, suggested parameters to be included in the KSCAT, and integration of technology. Our ultimate desire is to invite experts to develop this new tool using an interdisciplinary approach and to benefit from our review in pursuing the next steps. The development of a KSCAT should start with regular and interdisciplinary consortium meetings of experts; the tool should then be tested for its usability, specificity, and practicality; and, finally, it should be used in real-life pharmacovigilance practices, as well as in research by health authorities, regulators, decision-makers, scientists, and clinicians. A KSCAT would support the provision of reliable and reproducible measures of the relationship likelihood in suspected cases of ADR to overcome uncertainty and provide a standardized approach.

Keywords: DIAKI; causality assessment tool; drug safety; drug-induced acute kidney injury; pharmacoepidemiology; pharmacovigilance.