Impact of the 13-valent pneumococcal conjugate vaccine on incidence of all-cause pneumonia in adults ≥ 60 years: a population-based cohort study

 

Objectives There is an ongoing debate about the optimal pneumococcal vaccination strategy in adults. For the 13-valent conjugate vaccine (PCV-13), a large randomized trial showed significant efficacy against vaccine type pneumococcal pneumonia, but a non-significant 5% reduction of all-cause pneumonia. To our best knowledge there are no additional data on the effectiveness of PCV-13 on all-cause pneumonia.

Methods We performed a population based cohort study including adults ≥ 60 years of age (n = 516 144) based on statutory health insurance data. PCV-13 vaccination status was collected from 2012 to 2016. Patients with PPV-23 vaccination between 2009 and 2016 were excluded. The primary outcome all-cause pneumonia incidence was evaluated 2014 – 2016 and identified via ICD-10 codes, ambulatory cases were validated by antibiotic prescription within 7 days. The effect of PCV-13 was analyzed after propensity score based matching including comorbidities, age, sex, and influenza vaccination.

Results We identified 11 395 individuals ≥ 60 years with PCV-13 but no other pneumococcal vaccination. After matching on the propensity score, we found a significant reduction of all-cause pneumonia from 1812/34 185 (5.30%) in non-vaccinated controls to 532/11 395 (4.67%) in the PCV-13 vaccinated cohort, resulting in a 0.63% (95%CI 0.07 – 1.20; p = 0.028) absolute and 11.9% relative risk reduction (NNV to prevent one pneumonia 159 [84 – 1429]). Subgroup analyses according to sex indicated PCV-13 effectiveness only in females (absolute risk reduction 0.79% [0.16 – 1.44], p = 0.015), but not in males (p = 0.62). Subgroup analysis according to age (60 – 79 years versus ≥ 80 years) showed a numerically higher absolute effectiveness in the very elderly.

Conclusions PCV-13 vaccination in adults ≥ 60 years was associated with a significant risk reduction of all-cause pneumonia.