Environmental factors associated with familial or non-familial forms of Paget's disease of bone.

Objectives: The most frequent mutation linked to Paget's disease of bone (PDB), p.Pro392Leu within SQSTM1 gene, leads to phenotypic characteristics of PDB, but this mutation is seemingly insufficient to result in complete pagetic osteoclast phenotype, suggesting that possible environmental factors play a role in PDB pathogenesis. We performed an exploratory study to identify environmental factors potentially associated with familial or non-familial form of PDB in the French-Canadian population.

Methods: We investigated environmental factors through a questionnaire in 176 pagetic patients, including 86 patients with a familial form, and 147 healthy controls. All participants lived in the same geographic area, within a 120km radius of Quebec City. Associations between environmental factors and familial and non-familial forms of PDB were searched.

Results: In the multivariate model adjusted for intra-familial correlation, PDB was associated with wood fired heating in childhood and/or adolescence (OR=2.10; 95% CI 1.13-3.90, P=0.02). In the multivariate model without considering correlation for family relatedness, familial form of PDB was associated with residency near a mine (OR=11.70; 95% CI 2.92-46.80, P<0.01) and hunting (OR=2.92; 95% CI 1.14-7.47, P=0.03). Wood fired heating during childhood and/or adolescence (P=0.02) was associated with both familial and non-familial forms.

Conclusions: In conclusion, PDB was significantly associated with wood fired heating in childhood and/or adolescence, regardless of the form of PDB, familial or not.