Population-Based Risk Assessment for Multiple Myeloma: A Novel Approach for Identifying Potential Environmental Associations.

Given the continued uncertainty of multiple myeloma (MM) etiology, environmental epidemiologic investigations remain an important approach for generating hypotheses regarding potentially significant exposures. We assessed MM incidence in Arkansas using a novel population-based approach that combines county agricultural and industrial characteristics with environmental hazard mapping techniques to determine case distribution throughout the state and to identify significant trends associated with case distribution. Our investigation revealed a significant association between manufacturing-dependent counties and MM incidence (OR = 1.26, p = 0.004), a significant inverse association between non-specialized counties and MM incidence (OR = 0.62, p < 0.00001), and no significant association between agriculture-dependent counties and MM incidence (OR=0.92, p=0.636). Analyses of sixteen selected industries and their associations with MM incidence revealed primarily wood-related industries (paper mills, sawmills, wood preservation, and softwood, veneer and plywood manufacturing) exhibited significant associations with MM incidence (OR= 1.79 – 2.02, p< 0.05). Trend analyses demonstrated increasing MM incidence with increasing proportion of the population employed in the aforementioned wood-related industries. This is the first such statewide assessment of associations between general environmental exposure and MM incidence within counties. The methods developed in this study can be applied to data from other states or regions to produce a larger body of information from several geographic areas regarding MM incidence or other disorders with suspected environmental associations. Subsequently, meta-analysis can be performed to support or refute the existence of apparent associations, provide insight regarding national trends of MM incidence, and potentially suggest additional sources of exposure for further investigation.