Ocular Adverse Events after Coronavirus Disease 2019 mRNA Vaccination: Matched Cohort and Self-Controlled Case Series Studies Using a Large Database.

PURPOSE: To investigate the risk of ocular adverse events after Coronavirus Disease 2019 (COVID-19) mRNA vaccination. DESIGN: Matched cohort and self-controlled case series (SCCS) studies. PARTICIPANTS: We used a population-based database of medical claims and vaccination records in a large Japanese city. In the matched cohort study, we identified individuals who received COVID-19 vaccination (BNT162b2) from February 2021 to September 2021. One control was selected from nonvaccinated individuals by matching time, date of birth, sex, Charlson comorbidity index, and the enrollment period for health insurance. In the SCCS study, we analyzed individuals who developed ocular adverse events. METHODS: In the matched cohort study, we applied the Kaplan-Meier estimator to estimate the cumulative incidence of ocular adverse events over 21 days after the first dose and 84 days after the second dose. In the SCCS method, we used conditional Poisson regression to estimate the incidence rate ratio (IRR) of ocular adverse events during the risk periods (0-21 days after the first dose and 0-84 days after the second dose) compared with the remaining periods. MAIN OUTCOME MEASURES: Composite outcome of uveitis, scleritis, retinal vein occlusion (RVO), and optic neuritis. RESULTS: There were 99 718 pairs eligible for the matched cohort study after the first dose (mean age, 69.3 years; male, 44%). The vaccinated and control groups developed 29 and 21 events, respectively, over 21 days after the first dose, and 79 and 28 events, respectively, over 84 days after the second dose. The differences in cumulative incidence (reference, the control group) were 2.9 (95% confidence interval, -14.5 to 19.1) events/100 000 persons and 51.3 (16.2-84.3) events/100 000 persons, respectively, for the first and second doses. The SCCS study showed the IRRs of 0.89 (0.62-1.28) and 0.89 (0.71-1.11) for the first and second doses, respectively. CONCLUSIONS: The matched cohort analysis found an increased risk for the composite outcome after the second dose; however, the SCCS analysis showed no increased risk. Considering that the SCCS can cancel out time-invariant confounders, the current results suggest that COVID-19 vaccination is unlikely to causally increase the risk of ocular adverse events. FINANCIAL DISCLOSURE(S): Proprietary or commercial disclosure may be found after the references.

Duration of influenza vaccine effectiveness in the elderly in Japan: A retrospective cohort study using large-scale population-based registry data.

BACKGROUND: The immune response to influenza vaccination in the elderly is likely to be lower than that in young adults. Clinical protection may not persist year-round in the elderly. However, the effectiveness of influenza vaccine in the elderly has not been adequately studied, especially in terms of the duration of effectiveness. METHODS: We used a linked database of healthcare administrative claims data and vaccination records maintained by the municipality of a city in Kanto region of Japan. We studied individuals who were aged 65 years or older at baseline and were followed up between April 1, 2014 to March 31, 2020. The duration of influenza vaccine effectiveness by age category was analyzed using a time-dependent piecewise Cox proportional hazard model with time-dependent vaccine status, prior season vaccination and covariates confirmed in the baseline period (age, sex, cancer, diabetes, chronic obstructive pulmonary diseases, asthma, chronic kidney diseases, and cardiovascular diseases). RESULTS: We identified an analysis population of 83,146 individuals, of which 7,401 (8.9%) had experienced influenza and 270 (0.32%) underwent influenza-related hospitalization. Individuals who were vaccinated during the first season (n = 47,338) were older than non-vaccinated individuals (n = 35,808) (average age, 75.8 vs. 74.1 years, respectively). The multivariable analysis showed a lower incidence of influenza in vaccinated individuals (hazard ratio [HR], 0.47; 95% confidence interval [CI], 0.43-0.51; P < 0.001), while the incidence of hospitalization for influenza did not differ significantly by vaccination status (HR, 0.79; 95% CI, 0.53-1.18; P = 0.249). Protective effectiveness against incidence was maintained for 4 or 5 months after vaccination in those aged 65-69 and 80-years, 5 months in 70-79 years. CONCLUSIONS: Our study identified moderate vaccine effectiveness in preventing the incidence of influenza in the Japanese elderly. Vaccine effectiveness showed a trend of gradual attenuation. Clinicians should suspect influenza infection even in those vaccinated, especially in elderly individuals who had received vaccination more than 4 or 5 months previously.

Validity of diagnoses of respiratory diseases recorded in a Japanese administrative database.

BACKGROUND: Validating the information recorded in administrative databases is essential. However, no study has comprehensively validated the accuracy of Japanese Diagnosis Procedure Combination (DPC) data on various respiratory diseases. Therefore, this study aimed to evaluate the validity of diagnoses of respiratory diseases in the DPC database. METHODS: We conducted chart reviews of 400 patients hospitalized in the departments of respiratory medicine in two acute-care hospitals in Tokyo, between April 1, 2019 and March 31, 2021, and used them as reference standards. The sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) of DPC data on 25 respiratory diseases were determined. RESULTS: Sensitivity ranged from 22.2% (aspiration pneumonia) to 100% (chronic eosinophilic pneumonia and malignant pleural mesothelioma) and was <50% for eight diseases, while specificity was >90% for all diseases. PPV ranged from 40.0% (aspiration pneumonia) to 100% (coronavirus disease 2019, bronchiectasis, chronic eosinophilic pneumonia, pulmonary hypertension, squamous cell carcinoma, small cell carcinoma, lung cancer of other histological types, and malignant pleural mesothelioma) and was >80% for 16 diseases. Except for chronic obstructive pulmonary disease (82.9%) and interstitial pneumonia (other than idiopathic pulmonary fibrosis) (85.4%), NPV was >90% for all diseases. These validity indices were similar in both hospitals. CONCLUSIONS: The validity of diagnoses of respiratory diseases in the DPC database was high in general, thereby providing an important basis for future studies.

Comparative effectiveness of BNT162b2 and mRNA-1273 booster dose after BNT162b2 primary vaccination against the Omicron variants: A retrospective cohort study using large-scale population-based registries in Japan.

BACKGROUND: Direct comparative effectiveness of booster doses of BNT162b2 and mRNA-1273 after BNT162b2 primary vaccination is unknown. METHODS: We investigated comparative effectiveness of BNT162b2 and mRNA-1273 booster dose using data from registry systems for vaccination and COVID-19 infection in a local city in Japan. We followed participants aged ≥16 years who completed the BNT162b2 primary vaccination between November 22, 2021, and April 15, 2022. We collected information on age, sex, vaccination status, vaccine type, and infection status. Age was categorized as 16-44, 45-64, 65-84, and ≥85 years. Vaccine effectiveness for mRNA-1273 and no booster vaccination against BNT162b2 was estimated using age-stratified Cox regression adjusted for age, sex, and days since the second vaccination. The estimated hazard ratios for mRNA-1273 and no booster vaccinations were integrated separately using random effects meta-analyses. RESULTS: During the study period, we identified 62,586 (40.4%), 51,490 (33.2%), and 40,849 (26.4%) participants who received BNT162b2, mRNA-1273, and no booster dose, respectively. The median age was 69, 71, and 47 years for BNT162b2, mRNA-1273, and no booster dose, respectively. The integrated hazard ratio with reference to BNT162b2 was 1.72 for no booster vaccination and 0.62 for mRNA-1273. The comparative effectiveness of mRNA-1273 was similar across age categories. CONCLUSIONS: Both homologous and heterologous vaccinations are effective against Omicron variants. In the head-to-head comparison, the effect was stronger in people who received heterologous vaccination than in those who received homologous vaccination. These findings may help improve logistics and decision making in future vaccination programs.

Intensive care unit versus high-dependency care unit for mechanically ventilated patients with pneumonia: a nationwide comparative effectiveness study.

BACKGROUND: Many mechanically ventilated patients in Japan are treated in high-dependency care units (HDUs) rather than intensive care units (ICUs). HDUs can provide intermediate-level care with reduced costs; however, there is limited evidence on whether mechanically ventilated patients should be treated in the ICU or HDU. METHODS: This was a comparative effectiveness study using a nationwide administrative database in Japan. We identified mechanically ventilated patients with pneumonia in ICU or HDU on the day of admission in the Japanese Diagnosis Procedure Combination inpatient database from April 2014 to March 2019. The primary outcome was 30-day in-hospital mortality. Propensity score matching analysis was performed to compare this outcome between patients treated in the ICU and HDU. The robustness of the analyses was evaluated with multivariable regression, overlap weighting, and instrumental variable analyses. FINDINGS: Of 14,859 mechanically ventilated patients with pneumonia, 7,528 (51%) were treated in the ICU and 7,331 (49%) were treated in the HDU. After propensity score matching, patients treated in the ICU had significantly lower 30-day in-hospital mortality than did those treated in the HDU (24.0% vs. 31.2%; difference, -7.2%; 95% confidence interval, -10.0% to -4.4%). The multivariable regression, overlap weighting, and instrumental variable analyses showed a similar direction and magnitude of association. INTERPRETATION: Critical care for mechanically ventilated patients with pneumonia in the ICU was associated with a 7.2% decrease in 30-day in-hospital mortality vs. care in the HDU. Residual confounding may still play a role in the effect estimates. FUNDING: This study received funding from Ministry of Health, Labour and Welfare, Japan, and Ministry of Education, Culture, Sports, Science and Technology, Japan.