Trends in cancer diagnoses among inpatients hospitalized with stroke

Cancer, by conferring a hypercoagulable state, may lead to an ischemic stroke. Relatively little is known about the prevalence and evolution of cancer among stroke patients over the last decade.

We used the Nationwide Inpatient Sample to identify discharges with any InternationalClassification of Diseases, Ninth Revision, diagnosis code for cancer and ischemic stroke from 1997 to 2006. We then calculated age-adjusted yearly acute ischemic stroke hospitalization rates among adult populations with and without cancer.

Prevalence of cancer among hospitalized stroke patients increased from 1997 to 2006 (N = 31,075 [9.1% of all ischemic stroke hospitalizations] to 34,138 [10.6%], P < .0001). The most common types of cancer among hospitalized stroke patients in 1997 and 2006 were prostate (21% versus 19%), breast (19% versus 19%), gastrointestinal (16% versus 13%), and colorectal (13% versus 13%). Over the decade there was a significant decrease in the prevalence of stroke hospitalizations (slope -3.02, 95% confidence interval -3.69 to -2.34), but not among cancer patients (slope 1.35, 95% confidence interval -0.88 to 3.58).

About 1 in 10 hospitalized ischemic stroke patients in the United States has comorbid cancer, and there has been a slight rise in this rate over the last decade. This is likely due to enhanced survival from better cancer treatments, but further study is warranted.