Occupational exposures among hairdressers and the occurrence of hormone-related conditions.

Abstract

To investigate the association between hairdresser exposures and hormone-related conditions. Using data from 50 800 eligible Sister Study participants (enrolled 2003-2009, aged 35-74 years), we estimated ORs and 95% CIs for associations between ever working as a hairdresser (n=1803) and prevalent fibroids, endometriosis, hysterectomy and oophorectomy. We estimated HRs and 95% CI for incident fibroids, endometriosis, breast, uterine and ovarian cancers among ever hairdressers versus never hairdressers. We also examined associations of hormone-related diseases and professional use of products such as bleach, perms, chemical straighteners, permanent hair colour, hairspray, barbicide, formaldehyde and alcohol, comparing data from 985 long-term hairdressers who worked ≥2 years to non-long-term hairdressers (never workers and those working <2 years). Ever-hairdressers were more likely than never-hairdressers to have had a prebaseline hysterectomy (OR=1.23: 95% CI 1.11 to 1.36). Hysterectomies were more common among long-term hairdressers with more frequent applications of perms, chemical straighteners and permanent hair colour compared with less frequent applicators or never hairdressers. Ever-hairdressers had higher rates of incident endometriosis (477 cases, HR=1.61: 95% CI 1.08 to 2.38) compared with never-hairdressers, but there were no notable associations between working as a hairdresser and fibroids (1805 cases, HR=1.04: 95% CI 0.80 to 1.34), breast cancer (4628 cases, HR=0.98: 95% CI 0.83 to 1.16), ovarian cancer (300 cases, HR=1.33: 95% CI 0.77 to 2.29) or uterine cancer (447 cases, HR=1.04: 95% CI 0.60 to 1.77). In race-stratified analyses, Black hairdressers were more likely to be diagnosed with fibroids than Black never-hairdressers (201 cases, HR=1.56: 95% CI 0.93 to 2.62). Hairdresser occupation was associated with increased odds of hysterectomy and increased rates of incident endometriosis and possibly fibroids among Black women.