Disease profile and health-related quality of life (HRQoL) using the EuroQol (EQ-5D + C) questionnaire for chronic metallic mercury vapor intoxication

Abstract

BackgroundToxic mercury is still being used today for example by workers mining gold, resulting in diverse health symptoms in users and individuals in proximity. A considerable burden of disease (BoD) can be assumed, while previous analyses were limited by data scarcity. Besides limited epidemiological data, neither data about the health-related quality of life (HRQoL) nor about the disease severity (disability weight, DW) is available. The aim of the project was to develop disease profiles of chronic metallic mercury vapor intoxication (CMMVI) by including the HRQoL to improve the data basis for BoD analyses of gold miners exposed to mercury.MethodsDisease profiles comprising the disease label [a], differentiation into disease stages [b], description of the cause of exposure [c], a list of common symptoms [d], and an assessment of the HRQoL [e] were developed using expert elicitation and literature search. The HRQoL was assessed by experts using the five EuroQol dimensions accompanied by the cognition add-on questionnaire (EQ-5D + C).ResultsThe ten sources used for the analyses (interview transcript, presentation, and eight literature reviews) identified more than 250 terms describing 85 distinguishable health effects of CMMVI. The analysis revealed 29 common symptoms that were frequently mentioned. Moderate and severe CMMVI cases differ regarding their symptoms and/or symptom severity and HRQoL, resulting in the EQ-5D + C-3L codes 121222 and 233333, respectively.ConclusionsThe profiles should be used to facilitate the ascertainment of CMMVI cases, to compare the HRQoL with other diseases, to derive DWs for improving BoD estimates, and to foster discussions about how to reduce the associated burden.Electronic supplementary materialThe online version of this article (doi:10.1186/s12955-015-0388-0) contains supplementary material, which is available to authorized users.

Health-related quality of life (EQ-5D + C) among people living in artisanal and small-scale gold mining areas in Zimbabwe: a cross-sectional study

“…Four participants of this study, one having CMI (Additional files 4 and 7) reported a health state, which is the same or worse than the health state for a moderate (121222) form of chronic metallic mercury vapor intoxication assessed by expert interviews [22]. This could mean, that experts focus on the disease and its health limitations and therefore rate a health condition worse than the affected people would rate it [42].…”

“…This could mean, that experts focus on the disease and its health limitations and therefore rate a health condition worse than the affected people would rate it [42]. None of the participants stated a health state which corresponds to the health state for a severe (233333) form of chronic metallic mercury vapor intoxication [22]. It is assumable, that people suffering from the most severe form of this intoxication are no longer able to work [15] or to participate in such a study like this.…”

“…Furthermore, the HRQoL among miners in ASGM in Zimbabwe has been investigated and compared with Zimbabwean urban population [21]. The health states, as part of the HRQoL, for a moderate and a severe form of chronic metallic mercury vapor intoxication were assessed using expert interviews [22].…”

Global Burden of Disease of Mercury Used in Artisanal Small-Scale Gold Mining

“…Besides the DW of a moderate CMMVI, a different DW for severe CMMVI is available. 21 However, the available data do not allow a stratified estimate on the prevalence distinguishing between moderate and severe cases. Because of its severe effects on the human body, such as severe coordination problems and difficulties in concentrating, and its restrictions on the quality of life, such as not being able to perform usual activities, 21 it is likely that this health condition would restrict mining work.…”

“…Recently, DWs for chronic mercury intoxication as a result of metallic mercury vapor were derived to improve the input data for DALY quantifications. 20 The DWs were based on detailed case descriptions of moderate and severe chronic metallic mercury vapor intoxication (CMMVI), 21 which is assumed to be the main health outcome resulting from exposure to mercury in ASGM.…”