Cognitive impairment affects treatment choices for breast cancer

Co-existing cognitive impairment affects the way older breast cancer patients are treated, a recent study has found. For those with severe dementia, standard cancer treatment may be too much.

Researchers conducted a prospective, multicentre cohort study of 3,416 older women (aged ≥70 years) with primary operable breast cancer. The mini-mental state examination (MMSE), or a previous diagnosis of dementia, was used to evaluate participants’ cognitive state. Outcomes of interest included overall survival (OS) and breast cancer-specific survival, as compared between patients with vs without cognitive impairment.

Of the participants, 2,938 were deemed cognitively healthy, while 336, 59, and 83 patients had mild, moderate, and severe cognitive impairment, respectively.

Most of the patients (82.3 percent) underwent surgery, with or without adjuvant treatments, while 14.8 percent received primary endocrine therapy (PET). Treatment choices differed according to cognitive status. PET, for example, was given to only 12.4 percent of women who were cognitively healthy, as opposed to 22.3 percent, 35.6 percent, and 51.8 percent of participants with mild, moderate, and severe impairment, respectively.

Adjuvant chemotherapy and radiotherapy were both more common in cognitively healthy participants, but the differences in numbers did not reach statistical significance.

Cognitive status likewise affected outcomes. Women with cognitive impairment had significantly lower overall survival (hazard ratio, 2.10, 95 percent confidence interval, 1.77–2.5; p<0.001). This effect remained significant, though strongly weakened in magnitude, after adjusting for confounders.

“[T]he severity of cognitive impairment is a significant predictor of PET for older women with breast cancer, and cognition appears to play a significant part in deciding how to treat older women with breast cancer,” the researchers said.