PPSV23 Prevents Hospitalization Risk Due to Community-Acquired Pneumonia

The 23-valent pneumococcal polysaccharide vaccine (PPSV23, Pneumovax 23; Merck Sharp & Dohme Corp) prevented 25.2% and 44% of hospitalizations due to non-severe community-acquired pneumonia (CAP) and severe CAP, respectively. According to results published in Human Vaccines & Immunotherapeutics, PPSV23 demonstrated effective reductions in the risk of hospitalizations due to CAP for older individuals.¹

PPSV23, hospitalization, pneumonia, pneumococcal, CAP | Image Credit: © Bernard Chantal | stock.adobe.com

In October 2024, the CDC Advisory Committee on Immunization Practice expanded the recommendation for the use of certain pneumococcal vaccines to include individuals 50 and older. In the expansion, the CDC suggests that those 50 years and older should discuss their need for vaccination with a health care provider. The vaccines included as part of the recommendation include the 20-valent pneumococcal conjugate vaccine (Prevnar 20; Pfizer) and pneumococcal 21-valent conjugate vaccine (Capvaxive; Merck). However, there was no mention in this recommendation for PPSV23.²

Earlier in 2024, updated safety data for PPSV23 showed that the vaccine is not associated with higher risk of serious systemic adverse events, which has been a concern due to outdated evidence. The data demonstrate that there is no increased risk of cardiovascular, neurological, or immunological events after vaccination. Further, Bell palsy and Guillain-Barré syndrome were not associated with vaccination, and there were no increased risk of sepsis, thrombocytopenia, or anaphylaxis.³

In the current study, investigators divided patients into groups, including those with primary CAP and patients with other respiratory tract infections. Their aim was to determine the effectiveness of the vaccine in preventing hospitalization due to CAP. Individuals were included between January 1, 2023, to June 30, 2023, and a total of 40,115 individuals were hospitalized in the respiratory departments of 103 hospitals in Suzhou, China. Approximately 17,822 had primary pulmonary infection, 7931 had other types of pneumonia, including bacterial and viral pneumonia, 5805 with CAP, and 5881 with other respiratory tract infections, including bronchitis, acute upper respiratory tract infection, and others. Investigators included the patients with all-cause CAP and the 5881 patients with other respiratory tract infections.¹

Individuals with CAP had lower vaccination rates with PPSV23 compared with the control group at 3.27% and 4.81%, respectively. Investigators noted that the differences in males between the 2 groups (52.9% and 54.79%, respectively) was statistically significant and the median age of cases was higher than the controls at 76 years and 75 years, respectively.¹

Older adults who received PPSV23 had a lower risk of hospitalization due to all-cause CAP with a lowered the risk of hospitalization by 26.7%. In the univariate and multivariate analysis, the risk of CAP was lower in older men compared with older women, according to the investigators. Furthermore, individuals who had any 1 or 2 or more comorbidities had a higher risk of CAP compared with those who did not have common comorbidities. Non-severe CAP individuals had a lower vaccination rate compared with the control group at 3.43% and 4.81%, respectively. Similarly, severe CAP had a lower vaccination rate compared with the control group at 1.94% and 4.81%, respectively. The risk of non-severe CAP was also lower for older men than women, but severe CAP was higher for older men than women, according to the results.¹

REFERENCES

1. Liu N, Wang L, Luan L, Wang H. Preventive effects of 23-valent pneumococcal polysaccharide vaccine on community-acquired pneumonia hospitalization in older individuals in China: A case-control study. Hum Vaccin Immunother. 2024;20(1):2420450. doi:10.1080/21645515.2024.2420450

2. Gallagher A. ACIP Lowers Pneumococcal Vaccination Recommendation to Age 50. Pharmacy Times. October 24, 2024. Accessed December 4, 2024. https://www.pharmacytimes.com/view/acip-lowers-pneumococcal-vaccination-recommendation-to-age-50

3. Gallagher A. Medication Safety: Analysis Shows PPSV23 Is Not Associated With Higher Risk of Serious Outcomes. Pharmacy Times. March 15, 2024. Accessed December 4, 2024. https://www.pharmacytimes.com/view/medication-safety-analysis-shows-ppsv23-is-not-associated-with-higher-risk-of-serious-outcomes