Patients with Alzheimer’s Disease Receive Less Aggressive Treatment for Breast Cancer

Abstract & Commentary

By William B. Ershler, MD, INOVA Fairfax Hospital Cancer Center, Fairfax, VA; Director, Institute for Advanced Studies in Aging, Washington, DC and is Editor of Clinical Oncology Alert. Dr. Ershler is on the speaker’s bureau for Amgen and does research for Ortho Biotech.

Synopsis: In a pattern-of-care analysis performed by linking the SEER database with Medicare claims data, it was found that, matched for age, breast cancer patients who had coexisting Alzheimer’s disease were less likely to have surgery, radiation or chemotherapy than those without Alzheimer’s disease.

Source: Gorin SS, et al. Treatment for breast cancer in patients with Alzheimer’s disease. J Am Geriatr Soc. 2005;53:1897-1904.

Alzheimer’s disease (AD) and breast cancer are both diseases of late life. Breast cancer occurs 5 times more frequently in women 65 years and older and the same is roughly observed for AD. It has been estimated that AD occurs in approximately 1 percent of people older than 65 and perhaps as high as 50 percent for those older than 95 years of age.1 Although the prevalence of breast cancer increases with age, diagnostic and treatment efforts become less intense. Of the many possible explanations for this, one is the concern that cognitive impairment may render an individual incapable of following screening recommendations or understanding the complexities of potentially toxic treatments.

The current study capitalized on the SEER (Surveillance, Epidemiology, and End Results) database and linked this to Medicare billing records for the purpose of evaluating breast cancer treatment in patients with AD. The SEER database provides detailed information regarding tumor pathology including, for patients with breast cancer, tumor size, grade, stage, and hormone receptor status. In addition, information about treatment and cause of death is also retrievable. A total of 137,391 cases of breast cancer from January 1992 to December 1999 were reviewed in the context of this research question and linked to Medicare records. Patients who were diagnosed before the age of 65 years or those who did not subscribe to Medicare A and B plans were excluded and the remainder (50,460 cases) served as the study population.

As predicted, the data indicate less overall breast cancer treatment provided for patients with coexisting AD. Those with AD were diagnosed with more advanced disease, had a lower likelihood of surgery (OR = 0.60; 95% CI = 0.46-0.81), radiation (OR = 0.31; 95% CI = 0.23-0.41), and chemotherapy (OR = 0.44; 95% CI = 0.34-0.58) than those without AD. Breast conserving treatment occurred more frequently in breast cancer patients with AD while mastectomy, radiation treatment, and chemotherapy occurred less frequently. Only 3.3% of the patients with AD received chemotherapy vs 10.5% of those without AD. The effects of race, stage, age, socioeconomic status, and co-morbidities other than dementia were evaluated by multivariate and logistic regression analysis. After stratifying by age, the greatest differences with regard to treatment occurred between ages 80 and 89, with patients diagnosed with AD being one half as likely to have surgery, one-quarter as likely to receive radiation treatment (if they had received breast-conserving surgery) and one half as likely to receive chemotherapy as other female Medicare beneficiaries. Thus, breast cancer patients with AD had a statistically significant decrease in any treatment when compared to their counterparts without AD, and the difference was magnified among the oldest patients.

Commentary

This is an interesting, albeit not at all surprising, report demonstrating lower rates of treatment for patients with AD. The findings are reminiscent of similar observations for other groups, including the elderly as a whole, minorities, and persons with other chronic conditions.2-4 Also, the inclination to provide less-aggressive treatment is consistent with a similar SEER-Medicare linked analysis of colorectal cancer treatment.5 With regard to these discrepancies observed for patients with dementia, there are a number of possible explanations, some defensible and some not. The fact remains that we have little data available on optimal treatment of cancer in general in patients in late-life and it may well be that non-treatment decisions made for the wrong reasons (eg, ageism) were actually correct.

Medical oncologists are going to be increasingly confronted with this issue as our population ages, particularly in the oldest-old sector. Defining optimal treatment for patients in this group is an imperative for investigative oncologists, and until data are available, practitioners will be faced with presenting to patients or their families treatment options unsubstantiated by research or no treatment at all. It is time to provide the evidence!

References

1. Cummings JL, Cole G. Alzheimer disease. JAMA. 2002;287:2335-2338.

2. Hurria A, et al. Factors influencing treatment patterns of breast cancer patients age 75 and older. Crit Rev Oncol Hematol. 2003;46:121-126.

3. McWhorter WP, et al. Black/white differences in type of initial breast cancer treatment and implications for survival. Am J Public Health. 1987;77:1515-1517.

4. Kiefe CI, et al. Chronic disease as a barrier to breast and cervical cancer screening. J Gen Intern Med. 1998;13:357-365.

5. Gupta SK, et al. Patterns of presentation, diagnosis, and treatment in older patients with colon cancer and comorbid dementia. J Am Geriatr Soc. 2004;52:1681-1687.