TY - JOUR

T1 - Occupational exposure to solar ultraviolet B radiation and risk of subtypes of breast cancer in Danish women

AU - Pedersen, Julie Elbaek

AU - Strandberg-Larsen, Katrine

AU - Andersson, Michael

AU - Hansen, Johnni

PY - 2021

Y1 - 2021

N2 - Objectives Previous epidemiological studies have indicated that solar ultraviolet B radiation (UVR) may have a protective effect on breast cancer. However, the evidence remains inconclusive. Despite the fact that outdoor work history may be considered a reliable measure of long-Term UVR exposure, objective information on lifetime employment has not been included in previous investigations focusing on breast cancer. To address this issue, we explored the association between occupational UVR exposure and female breast cancer, including subtypes. Methods A total of 38 375 women under the age of 70 years were identified with primary breast cancer using the Danish Cancer Registry. Five female controls born on the same year, alive and free of breast cancer at the time of diagnosis of the index case, were randomly selected from the Danish Civil Registration System. The Danish Supplementary Pension Fund Register was used to retrieve full employment history, and a job exposure matrix was used to assess occupational UVR exposure. Conditional logistic regression with adjustment for important confounders was used to estimate the OR. Results We observed no overall association between occupational UVR exposure and breast cancer. After the age of 50 years, longer duration of UVR exposure (≥20 years: OR=0.83, 95% CI 0.75 to 0.92) and highest cumulative exposure (OR=0.89, 95% CI 0.83 to 0.95) were inversely associated with risk. Our results did not reflect any notable risk difference by oestrogen receptor status. Conclusions This study indicates an inverse association between long-Term occupational UVR exposure and late-onset breast cancer. This finding needs further attention in future occupational studies.

AB - Objectives Previous epidemiological studies have indicated that solar ultraviolet B radiation (UVR) may have a protective effect on breast cancer. However, the evidence remains inconclusive. Despite the fact that outdoor work history may be considered a reliable measure of long-Term UVR exposure, objective information on lifetime employment has not been included in previous investigations focusing on breast cancer. To address this issue, we explored the association between occupational UVR exposure and female breast cancer, including subtypes. Methods A total of 38 375 women under the age of 70 years were identified with primary breast cancer using the Danish Cancer Registry. Five female controls born on the same year, alive and free of breast cancer at the time of diagnosis of the index case, were randomly selected from the Danish Civil Registration System. The Danish Supplementary Pension Fund Register was used to retrieve full employment history, and a job exposure matrix was used to assess occupational UVR exposure. Conditional logistic regression with adjustment for important confounders was used to estimate the OR. Results We observed no overall association between occupational UVR exposure and breast cancer. After the age of 50 years, longer duration of UVR exposure (≥20 years: OR=0.83, 95% CI 0.75 to 0.92) and highest cumulative exposure (OR=0.89, 95% CI 0.83 to 0.95) were inversely associated with risk. Our results did not reflect any notable risk difference by oestrogen receptor status. Conclusions This study indicates an inverse association between long-Term occupational UVR exposure and late-onset breast cancer. This finding needs further attention in future occupational studies.

KW - environment

KW - epidemiology

KW - occupational health

KW - women

U2 - 10.1136/oemed-2020-107125

DO - 10.1136/oemed-2020-107125

M3 - Journal article

C2 - 33531359

AN - SCOPUS:85100408663

VL - 78

SP - 286

EP - 292

JO - Occupational and Environmental Medicine

JF - Occupational and Environmental Medicine

SN - 1351-0711

IS - 4

ER -