PCV13 Tied to Fewer Pneumonia Hospitalizations in Older Adults

The 13-valent pneumococcal conjugate vaccine (PCV13; Prevnar 13) may have averted 35,000 hospitalized pneumonia cases among Medicare Part A/B recipients in recent years, a cohort study suggested.

From 2014 to 2017, the vaccine effectiveness with PCV13 among this population was estimated at 6.7% (95% CI 5.9-7.5) for hospitalized pneumonia, including 4.7% (95% CI 3.9-5.6) for pneumonia acquired outside the healthcare setting and 5.8% (95% CI 2.6-8.9) for lobar pneumonia cases, reported Miwako Kobayashi, MD, MPH, of the CDC in Atlanta, and colleagues.

This translated to an estimated 35,127 cases of hospitalized pneumonia averted, including an estimated 24,643 fewer cases of pneumonia acquired outside the healthcare setting and 1,294 fewer lobar pneumonia cases, according to their findings in JAMA Internal Medicine.

"Vaccine effectiveness was lower among older age groups compared with younger age groups, as well as in adults with underlying medical conditions compared with adults without underlying medical conditions," the researchers wrote, adding that effectiveness was also observed among adults with immunocompromising conditions, who were largely excluded from clinical trials.

The Advisory Committee on Immunization Practices (ACIP) in 2014 recommended the use of PCV13 for all adults 65 and older but subsequently removed this routine recommendation in 2019, in favor of shared decision-making, when surveillance data suggested the vaccine had a limited association with reducing PCV13-type invasive pneumococcal disease.

Writing in an accompanying commentary, Amber Hsiao, MPH, and Nicola Klein, MD, PhD, both of the Kaiser Permanente Vaccine Study Center in Oakland, California, noted that the findings "may have important policy and research implications," given that the 2021 ACIP recommendation reinstated a routine recommendation for PCV in people 65 and older with the newly available 15-valent and 20-valent pneumococcal vaccines (PCV15 and PCV20).

Prior research on the effectiveness of PCV13 has been mixed, but the new findings "are consistent with U.S. estimates including our recent one from Kaiser Permanente Northern California," according to Hsiao and Klein.

"Although the populations varied depending on low-risk and high-risk definitions," Medicare-age adults who received PCV13 had a 10.0% (95% CI 2.4-17.0) reduction in hospitalized all-cause pneumonia, they noted. And a cohort study from Kaiser Permanente Southern California found a "similar, although not significant" 8.8% (95% CI -0.2 to 17.0) reduction in hospitalized pneumonia.

"Based on these emerging data, we are hopeful that the recently streamlined ACIP routine recommendation for the higher-valent pneumococcal conjugate vaccines in all adults 65 years or older will increase vaccination rates in this population and further reduce pneumonia hospitalizations and other serious sequelae," said Hsiao and Klein.

Kobayashi's group noted that "use of PCV15 and PCV20 in adults has the potential to further reduce pneumococcal disease incidence in U.S. adults, given the broader serotype coverage and expanded eligibility for PCV receipt in adults younger than 65 years."

The current study looked at 24,121,625 Medicare beneficiaries enrolled from September 2014 to December 2017, of which 20.5% had received the PCV13 vaccine. At baseline, 0.8% were vaccinated against PCV13, which grew to 41.5% by study end.

The cohort represents nearly half (49%) of the U.S. population age 65 or over. Of these, 57% were women, and 46% were 75 years or older. Most were white (86%), while 8% were Black, 2% were Hispanic, and 2% Asian. In the vaccinated group, 34.3% had no comorbidities versus 48.2% in the unvaccinated group.

In total, there were 162,579 pneumonia hospitalizations in beneficiaries who received a PCV13 vaccination, with 130,939 cases acquired outside the healthcare setting, and 9,029 lobar pneumonia cases. In individuals who received no PCV13 vaccine, there were 755,467 pneumonia hospitalizations, including 590,482 cases of pneumonia acquired outside healthcare and 29,014 lobar pneumonia cases.

Highlighting the hospitalizations averted, Hsiao and Klein noted that the average cost per hospitalized pneumonia episode in people 65 and older had been estimated to reach nearly $11,000 prior to the initial 2014 recommendations.

"While costs will vary depending on individual risk, preventing pneumonia hospitalizations in older, vulnerable populations using an available, effective vaccine offers value from a clinical and public health perspective," the duo wrote.

Correction: This article has been updated to include the Kaiser Permanente Northern California study cited by the commentary authors.

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