Scheduling early primary care follow-up after pneumonia: A retrospective target trial emulation in five hospitals

Current guidelines make no recommendations on discharge interventions or scheduling outpatient follow-up after hospitlization for commnity-acquired pneumonia (CAP).

To assess the impact of scheduling early primary care follow-up prior to discharge home among survivors of hypoxemic CAP hospitalizations.

We conducted an observational target trial emulation of 3332 adults (age ≥18 years) with hypoxemic CAP (requiring ≥2 liters oxygen) admitted to a 5-hospital system and discharged home between 2019 and 2024. Treated and control patients were propensity score-matched with replacement on 30 prespecified confounders. Treated patients had early primary care follow-up (to occur within 14 days of discharge) scheduled predischarge. The Average Treatment effect on the Treated (ATT) on a primary composite outcome of postdischarge mortality or readmission was assessed 90 days postdischarge.

After weighting, the matched cohort included 894 patients with equal treated and control groups (median age 66 [interquartile range [IQR]: 54-77]). Treated patients completed 14-day follow-up more frequently compared with controls (85% vs. 36%). The observed reduction in the incidence of the primary outcome in the treated group was not statistically significant (ATT: -1.1% [CI: -7.3, 5.1], p = 0.72). In a post-hoc analysis of 301 treated patients who subsequently completed scheduled follow-up, there was a statistically significant reduction in the incidence of the primary outcome in the treated group (ATT: -7.0% [CI: -13.9, -0.01], p = 0.049).

Scheduling early primary care follow-up after hospitalization for hypoxemic CAP was associated with reduced 90-day readmission and mortality only among patients who completed follow-up. Future work is needed to enhance the completion of scheduled primary care follow-up for hypoxemic CAP survivors.