Analyzing excess mortality from cancer among individuals with mental illness

MedicalResearch.com: eInterview with Siran M. Koroukian, Ph.D.
Population Health and Outcomes Research Core,
Clinical & Translational Science Collaborative
Associate Professor Department of Epidemiology and Biostatistics
School of Medicine Case Western Reserve University
Cleveland, OH 44106-7281

MedicalResearch.com: What are the main findings of the study?

Dr. Koroukian: Among individuals who died of cancer, those with mental illness (MI) died an average of 10 years earlier than those without MI.

Overall, there was excess mortality from cancer associated with having mental illness in all the race/sex strata: SMR, 2.16 (95% CI, 1.85-2.50) for black men; 2.63 (2.31-2.98) for black women; 3.89 (3.61-4.19) for nonblack men; and 3.34 (3.13-3.57) for nonblack women.

We note statistically significant higher SMRs for every anatomic cancer site in nonblack men and women and for most cancer sites in black men and women.

Except among Black women, the highest SMR with statistical significance was observed for laryngeal cancer (SMR, 3.94 [1.45-8.75] in black men, 6.51 [3.86-10.35] in nonblack men, and 6.87 [3.01-13.60] in nonblack women).

In Black women, the highest SMR was noted for the kidney and renal pelvis (8.54 [4.49-14.85]). SMRs for cancers of the urinary tract were also considerably elevated in nonblack women and men.

More than 5-fold excess mortality from hepatobiliary cancer was observed, especially in nonblack men and black women (SMR, 5.39 [3.75-7.52] and 5.26 [2.56- 9.65], respectively).

Finally, we observed SMRs elevated 3-5 times for cancer of the lung, trachea, and bronchus (SMR, 4.33 [3.82-4.88] in nonblack men, 4.22 [3.75-4.72] in nonblack women, and 2.99 [2.33-3.78] in black women).

MedicalResearch.com: Were any of the findings unexpected?

Dr. Koroukian: The finding that excess mortality from respiratory tract cancer (lung, trachea and bronchus) was observed at a higher magnitude among nonblacks than blacks across sex strata remains puzzling.

In the general population, a case-control study that examined sex-race differences in the risk of lung cancer risk associated with cigarette smoking showed that for a given level of smoking, blacks were at higher risk than whites of developing lung cancer (34). Studies also reported that although African Americans begin smoking later in life (35, 36) than whites, their rates of cessation are lower, (35-37) and they use brands with higher tar yields (38, 39).

Given this evidence, we would have expected a greater magnitude of excess mortality to be observed among blacks. We speculate that competing causes of death may be a possible explanation of this finding.

MedicalResearch.com: What should clinicians and patients take away from your report?

Dr. Koroukian: Our findings support the necessity for persons with MI to also have a primary care physician, whose focus is on preventive health care, including primary prevention and screening for early detection of disease, cancer risk assessment and screening, and health behavior assessment and counseling. Our findings also suggest a need for more intensive and coordinated efforts of medical, behavioral, and public health systems efforts in addressing 1) smoking cessation, 2) alcohol and substance abuse prevention and treatment, and 3) screening for and treatment of chronic hepatitis.

MedicalResearch.com: What recommendations do you have for future research as a result of this study?

Dr. Koroukian: Further investigation is necessary to not only explain variations of our results across the race/sex strata, but also to identify and address potential barriers to adequate primary and cancer-directed care.

Citation:

Analyzing excess mortality from cancer among individuals with mental illness.

Musuuza JS, Sherman ME, Knudsen KJ, Sweeney HA, Tyler CV, Koroukian SM.

Cancer. 2013 Apr 12. doi: 10.1002/cncr.28091.
[Epub ahead of print]

Last Updated on January 5, 2015 by Marie Benz MD FAAD