Elderly women with breast cancer who have severe mental illness have twice the risk of all-cause mortality as their peers without mental illness, and need more screening, surveillance, and coordinated care from primary care providers and specialists, researchers said.
Results from a large retrospective cohort study revealed an adjusted hazard ratio (HR) of 2.19 in breast cancer patients with severe mental illness compared with those without, according to Melissa L. Santorelli, PhD, of Rutgers School of Public Health in Piscataway, New Jersey, and colleagues.
The 5-year cumulative incidence for all-cause mortality in women with severe mental illness was 38.0%, compared with 19.4% in breast cancer patients without mental illness after adjusting for age, income, race, ethnicity, geographic location, and marital status (P<0.001), the study authors reported online in the Journal of Clinical Oncology.
There was also a statistically significant higher rate of all-cause mortality for women with depression (HR 1.39 after adjusting for age, income, race/ethnicity, SEER location, and marital status) and anxiety and depression (adjusted HR 1.26) than for women with no history of mental illness — likely because of late presentation and delayed diagnosis, the researchers said.
“Our descriptive analysis shows that patients with severe mental illness were diagnosed with later-stage breast cancer more frequently compared with patients without mental illness, which suggests that delayed diagnosis might play a role in survival disparities.”
Breast cancer patients with pre-existing severe mental illness may also be at increased risk of an aggressive form of advanced breast cancer, the researchers cautioned. Although a 20% increased hazard for breast cancer-specific death was observed in these patients, the adjusted HR (1.20) was not significant.
The study was conducted using SEER (Surveillance, Epidemiology, and End Results) and Medicare data on 19,028 women diagnosed with stages I to IIIa breast cancer from 2005 to 2007. Although 80% of patients did not have mental illness, 2.6% had a diagnosis of pre-existing bipolar disorder, schizophrenia, or some other psychotic disorder in the 3 years prior to breast cancer diagnosis. In addition, 7.7% of the study population had a diagnosis of depression, 6.0% had been diagnosed with anxiety, and 3.6% had both anxiety and depression.
When compared with women without mental illness, a larger proportion of patients with severe mental illness had:
- Diagnosis beyond stage I (46.4% versus 40.2%)
- Tumor larger than 20 mm (37.6% versus 30.3%)
- Poorly differentiated tumors (28.0% versus 24.0%)
- One or more positive lymph nodes at the time of initial diagnosis (40.7% versus 33.2%)
Clinicians need to be aware of these increased risks, step up screening efforts, and work collaboratively with other specialists to improve patient care, the researchers emphasized. Breast cancer patients with pre-existing severe mental illness were also more likely to have a lower median income, and were less likely to be married, the study showed.
“Primary care physicians must place an emphasis on early detection among women with severe mental illness to improve the likelihood that guideline-recommended screening mammograms occur,” Santorelli and colleagues wrote. “They also should work closely with psychiatrists and oncologists on the coordination of care for these patients.”
Similarly, oncologists need to make sure that surveillance mammograms are part of follow-up care for women with severe mental illness who are diagnosed with breast cancer, and more research is needed to better understand how mental illness reduces survival and to identify the best coordination of care models to improve patient outcomes.
Although breast cancer mortality has been declining over the past 30 years, it is estimated that in 2017, approximately 40,000 women in the United States will die from the disease. Elderly women have the highest incidence of breast cancer by age, the researchers pointed out.
The negative impact of mental health on mortality is not confined to patients with breast cancer, the team added. For example, an earlier meta-review of the literature showed that patients with severe mental disorders had an up to 150% increased risk of all-cause mortality.
In an accompanying editorial, Alison R. Hwong, MD, PhD, and Christina Mangurian, MD, of the University of California San Francisco, agreed that many questions remain — for example, the role of psychotropic medications in breast cancer morbidity and mortality needs to be better understood as well as how treatment decisions may differ for patients with severe mental illness.
“Future mixed-methods studies should examine patient understanding of and preference for treatment along with quality and outcomes data that compare women with and without severe mental illness.”
Noting that barriers to diagnosis and treatment currently exist for women with mental illness, Hwong and Mangurian warned that preventive care and treatment needs to be integrated into community mental health clinics “or these women will be overlooked.”
“We believe that preventive healthcare services should be delivered where women are already receiving care, especially for patients with severe mental illness who may have cognitive difficulties in accessing care, are marginally housed, and have low income,” the editorial continued. “Mobile mammography administrators could partner with community mental health clinics to deliver care where the patient already is being seen.”
Screening mammograms for this patient population wouldn’t be technically difficult to implement, but time and money will be needed as well as “an institutional commitment to improving overall medical care for people with severe mental illness.”
Limitations of the study, Santorelli et al noted, include the lack of assessment for psychiatric medications as well as the fact that behavioral factors such as alcohol and substance abuse were not evaluated. In addition, the results may not be generalizable to patients other than elderly women with Medicare coverage.
Santorelli reported having no conflicts of interest; several of the study coauthors reported financial relationships with industry.
Hwang and Mangurian reported having no conflicts of interest.
F. Perry Wilson, MD, MSCE Assistant Professor, Section of Nephrology, Yale School of Medicine and Dorothy Caputo, MA, BSN, RN, Nurse Planner