Background: The objective of this study is to evaluate rates of all-cause pneumonia among "at-risk" and "high-risk" children and adults in Germany-in comparison with age-stratified healthy counterparts-during the period following the 2006 recommendation for universal immunization of infants with pneumococcal conjugate vaccine.
Methods: Retrospective cohort design and healthcare claims information for 3.4 M persons in Germany (2009-2012) were employed. Study population was stratified by age and risk profile (healthy, "at-risk" [with chronic medical conditions], and "high-risk" [immunocompromised]). At-risk and high-risk conditions, as well as episodes of all-cause pneumonia, were identified via diagnosis, procedure, and drug codes.
Results and discussion: Rates of all-cause pneumonia were 1.7 (95 % CI 1.7-1.8) to 2.5 (2.4-2.5) times higher among children and adults with at-risk conditions versus healthy counterparts, and 1.8 (1.8-1.9) to 4.1 (4.0-4.2) times higher among children and adults with high-risk conditions. Rates of all-cause pneumonia among at-risk persons increased in a graded and monotonic fashion with increasing numbers of conditions (i.e., risk stacking).
Conclusions: An increased risk for all-cause pneumonia in German children and adults with a spectrum of medical conditions persists in the era of widespread pneumococcal vaccination, and pneumonia risk in persons with ≥2 at-risk conditions is comparable or higher than those with high-risk conditions.