title: Impact of comorbidity on management and mortality in women diagnosed with breast cancer.
abstract: To investigate associations between comorbidity burden, management, and mortality in women with breast cancer. A total of 42,646 women diagnosed with breast cancer between 1992 and 2008 were identified in two Clinical Quality Registers in Central Sweden. Breast cancer-specific, conditional breast cancer, competing-cause and all-cause mortality were estimated in relation to comorbidity burden assessed by the Charlson comorbidity index. All analyses were stratified by stage at diagnosis using competing risk analyses, and all-cause mortality was estimated as a function of follow-up time. Following adjustment for age and calendar period, breast conserving surgery was significantly less likely to be offered to women with severe comorbidity (OR 0.63; 95 % CI 0.58-0.69). Similarly, the proportion treated with radiotherapy, tamoxifen, or chemotherapy was lower in women with severe compared to those with no comorbidity. In women with early stage disease, breast cancer-specific mortality was higher among patients with severe comorbidity (sHR 1.47; 95 % CI 1.11-1.94). In all stages of breast cancer, conditional breast cancer and competing-cause mortality were elevated in women with severe comorbidity. For all stages, the relative risk of all-cause mortality between women with severe versus no comorbidity varied by time since diagnosis, and was most pronounced at early follow-up. Comorbidity affects treatment decisions and mortality. In women with early stage breast cancer, severe comorbidity was associated not only with conditional breast cancer, competing-cause and all-cause mortality, but also breast cancer-specific mortality. The observed differences in breast cancer-specific mortality may be due to less extensive treatment, impaired tumor defense and differences in general health status and lifestyle factors.
authors: Department of Medical Epidemiology and Biostatistics, Karolinska Institutet, PO Box 281, 171 77 Stockholm, Sweden. anders.berglund@ki.se
authors: Anders
authors: A
authors: Berglund
authors: Annette
authors: A
authors: Wigertz
authors: Jan
authors: J
authors: Adolfsson
authors: Johan
authors: J
authors: Ahlgren
authors: Tommy
authors: T
authors: Fornander
authors: Fredrik
authors: F
authors: Wärnberg
authors: Mats
authors: M
authors: Lambe
mesh_terms: D000970:Antineoplastic Agents / Q000627:therapeutic use; D001943:Breast Neoplasms / Q000453:epidemiology* / Q000401:mortality* / Q000628:therapy; D002423:Cause of Death; D015897:Comorbidity; D019468:Disease Management; D005260:Female; D006304:Health Status; D006801:Humans; D015412:Mastectomy, Segmental; D012306:Risk; D013548:Sweden / Q000453:epidemiology; D013629:Tamoxifen / Q000627:therapeutic use; D016896:Treatment Outcome
chemical_list: D000970:Antineoplastic Agents; D013629:Tamoxifen