Multiple myeloma (MM) is a haematological malignancy responsible for significant morbidity, yet our knowledge regarding MM aetiology remains limited. This analysis investigated whether an history of allergic conditions was associated with MM risk.
Incident cases (n=782) of MM were recruited mainly via cancer registries in Victoria and NSW. The controls included in the analysis (n=733) were siblings (n=436) or partners (n=297) of cases. Unconditional multivariable logistic regression was used to estimate odds ratios (OR), 95% confidence intervals (CI) and p-values for associations between self-reported allergic conditions (asthma, eczema, food allergy, hay fever) and MM risk. Missing data was handled with multiple imputation and causal diagram analysis was used for covariate selection.
We found an history of eczema was inversely associated with MM risk (OR = 0.54, 95% CI = 0.42 – 0.70), as was history of any allergic condition (OR = 0.68, 95% CI = 0.55 – 0.84). We found that compared with no history of allergic conditions, higher frequency of reported conditions was associated with increasingly lower estimated risk of MM; from one reported condition (OR = 0.76, 95% CI = 0.58 – 0.98), to four conditions (OR = 0.50, 95% CI = 0.23 – 1.09). No notable associations were identified for food allergy, asthma, or hay fever alone.
Our findings extend the knowledge of MM risk factor epidemiology in Australia. Research into potential underlying mechanisms might help explain disparate results of various studies examining the association between MM and allergic conditions.