Background: Immunocompromising conditions (ICs) are conditions that may be present at different moments in a person-s life and affect their health. In individuals with ICs, the body-s ability to effectively fight infections or mount a robust response to vaccination is weakened. It is thus important to understand the burden of ICs in part to inform public health policies on the procurement of vaccines for this population. However, no estimates of prevalence rates of ICs exist in Canada. Objective: Our objective was to address this gap. Intervention: We defined our list of ICs using different published sources and expert opinion. Using diagnoses coded with ICD-10 over a period of 14 years in the Discharge Abstract Database, we were able to estimate prevalence rates of ICs. Outcome: For all ICs combined and conservatively assuming a hospitalization rate of 0.1, general population prevalence rates is estimated at 1.8% for females and 1.9% for males. Inflammatory bowel disease, severe liver disease and severe cancers are among the most frequent ICs at all age groups and for both genders. Functional asplenia and Primary Immunodeficient conditions are mostly present at young ages. Transplantation and renal dialysis are also among the most frequent ICs. Conclusion: The prevalence of ICs estimated using DAD aligns with estimates obtained using other methods from other countries (2.7 to 6.6%) under certain assumptions for hospitalization rates. This work serves as the foundation for future investigation into obtaining more precise estimates of prevalence rates of ICs in Canada.

The authors have declared no competing interest.

This study did not receive any funding

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