178662 Cryptosporidiosis-related hospitalization in the US elderly population

Sunday, October 26, 2008

Siobhan M. Mor, BVSc BSc(Vet) , Division of Infectious Diseases, Tufts University School of Veterinary Medicine, North Grafton, MA
Elena Naumova, PhD , Department of Public Health and Community Medicine, Tufts School of Medicine, Boston, MA
The protozoan, Cryptosporidium spp., is a major cause of gastrointestinal illness worldwide. Though cryptosporidiosis has been a nationally notifiable disease in the USA since 1995, surveillance estimates are greatly undermined by failures to diagnose infection in the healthcare setting as well as report identified cases to health authorities. It is widely believed that immune senescence leads to enhanced vulnerability to cryptosporidiosis in the elderly, however this is not generally supported by surveillance data. The Centers for Medicare and Medicaid Services (CMS) databases present a novel means to investigate the burden of cryptosporidiosis in the elderly US population without the bias of underreporting. We abstracted all records (n=1304) containing a diagnosis of cryptosporidiosis-related (CR) illness in persons aged ≥65 years for the years 1991-2004. Annual rates of CR hospitalization were calculated and compared to surveillance data published by the CDC. Comorbidity and outcome of hospitalization was also assessed. CR hospitalizations increased during the study period, from 0.15 to 0.39 cases per 100,000 elderly per year, most likely due to increased awareness and testing. Comparison between the annual rates of CR hospitalization and CDC surveillance data revealed considerable state-to-state variation. Annual rates of CR hospitalization increased with age, such that the rate in persons aged >85 years more than doubled that in persons aged 65-74. Fluid and electrolyte imbalance was a common comorbidity while cancer was surprisingly infrequent. In-hospital death occurred in 5.4% of cases; the highest case fatality was in persons aged >85 (7.1%) and those with HIV (12.8%).

Learning Objectives:
1. Understand the limitations in existing surveillance data for cryptosporidiosis. 2. Describe the demographic and statewide trends in cryptosporidiosis among the US elderly. 3. Identify the main comorbidities afflicting elderly inpatients with cryptosporidiosis.

Keywords: Elderly, Infectious Diseases

Presenting author's disclosure statement:

Qualified on the content I am responsible for because: I contributed substantially and independently to the analysis and writing of the work described herein.
Any relevant financial relationships? No

I agree to comply with the American Public Health Association Conflict of Interest and Commercial Support Guidelines, and to disclose to the participants any off-label or experimental uses of a commercial product or service discussed in my presentation.