Incidence and Temporal trends of Primary Immunodeficiency: A Population Based Cohort Study

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Incidence and Temporal trends of Primary
ImmunodeficiencyA Population Based Cohort Study
Avni Joshi, MD
Allergy/Immunology
Pediatric Infectious Diseases
Mayo Clinic Rochester, Minnesota
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Background

• The field of PID is ever expanding
• Newer molecular defects are being recognized
• There is a greater impetus for a newborn screen
  for PID esp. SCID
• To determine the cost-effectiveness of routine
  screening, we will need population estimates of
  the incidence and prevalence of the disease in
  the population
• Incidence of PID is not known in USA
• Data based from registries in European
• countries

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Study Objective

• 1)Describe the epidemiology of PID in a defined
  population in Olmsted County, Minnesota over a
  31-year period using the Rochester Epidemiology
  Project (REP)
• 2) Evaluate factors associated with morbidity and
  mortality in the long term care of patients with
  PID

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Methods

• Unique record linkage system
• Non referent population
• Allows to ascertain the incident cases in a
  non-referent population
• Cases were initially identified using ICD-9
  diagnostic codes

Cohort Study Design
Dec. 31,2006
Jan1,1976
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Overall and B cell defect incidence rates
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Overall and Age-Specific Incidence of Primary
Immunodeficiency (PID) in Olmsted County,
Minnesota, USA from 1976 to 2006
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Distribution of different types of Primary
Immunodeficiency in Olmsted County, MN, USA
1976-2006
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Delay in diagnosis over three decades
lt/198617.5yrs 1987-19966.7yrs gt/19972.7yrs
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Delay in diagnosis and subsequent IgG
supplementation
Longer delay in diagnosis associated with
subsequent IgG replacement (Wilcoxon Sign rank
test, Plt0.001)
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Kaplan-Meier Survival Curves for subjects with
and without Primary Immunodeficiency (PID), in
Olmsted County, MN, 1976-2006