The Omicron variant of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) emerged in November 2021 and spread worldwide. This review summarizes the reported mortality and morbidity rates of coronavirus disease (COVID-19) caused by Omicron variants. In 21 previous studies, the mortality of patients infected with Omicron variants ranged from 0.01 to 13.1%, whereas that of those infected with previous variants was from 0.08% to 29.1%. The proportions of intensive care unit admissions and mechanical ventilation were lower for Omicron variants than for the previous variants. Future studies should clarify the mechanisms of transmissibility and severity of COVID-19 caused by the Omicron variants.

BACKGROUND

Acute exacerbation of idiopathic interstitial pneumonias (AE-IIPs) has a high mortality. However, there is no established treatment for AE-IIPs. Therefore, we aimed to compare the efficacy of high- and low-dose corticosteroid therapies in AE-IIPs patients.

METHODS

Data were retrospectively collected from the Japanese Diagnosis Procedure Combination database from July 2010 to March 2018. Adult patients with AE-IIPs who received high-dose (methylprednisolone at a dose of 500–1000 mg/day for 3 days starting within 4 days after admission) or low-dose (methylprednisolone at a dose of 100–200 mg/day for at least 5 days starting within 4 days after admission) corticosteroid therapy were identified. Eligible patients (n = 17,317) were divided into the high-dose (n = 16,998) and low-dose (n = 319) groups. A stabilized inverse probability of treatment weighting using propensity scores was performed to compare outcomes between the groups.

RESULTS

The primary outcome was in-hospital mortality, and the secondary outcomes were 28-day mortality, infections during hospitalization, length of hospitalization, duration of steroid use, and discharge to home. The in-hospital mortality rates of the high- and low-dose corticosteroid groups were 50.6% and 47.0%, respectively. In-hospital mortality did not significantly differ between the two groups after stabilized inverse probability of treatment weighting, and the odds ratio in the low-dose corticosteroid group was 0.86 (95% confidence interval: 0.64–1.16; p = 0.33). The secondary outcomes also did not significantly differ between the groups.

CONCLUSIONS

There was no significant difference in outcomes between patients with AE-IIPs who received high- and low-dose corticosteroid therapies.

BACKGROUND

This study aimed to calculate one-year total costs of incisional glaucoma surgery and laser therapy in a real-world clinical setting.

METHODS

We conducted a retrospective cohort study from July 2010 to March 2021 using the Diagnosis Procedure Combination database. We included patients hospitalized for incisional glaucoma surgery (trabeculectomy, trabeculotomy, tube shunt surgery, Ex-PRESS surgery, or iStent implantation) or laser therapy (laser peripheral iridotomy, surgical iridectomy, laser trabeculoplasty, cyclocryotherapy, or cyclophotocoagulation). The outcomes were total costs, including costs of hospitalization, re-admissions, antiglaucoma drugs, ophthalmic examinations, and outpatient visits for incisional glaucoma surgery and laser therapy within one year.

RESULTS

We identified 49,202 eligible hospitalizations. The one-year median total cost was 707,497 yen [interquartile range: 546,887–944,664 yen]. The median total cost was the highest in patients undergoing tube shunt surgery, followed by Ex-PRESS surgery, iStent implantation, and trabeculectomy. The number and cost of postoperative outpatient visits and length of hospital stay were higher in patients who underwent trabeculectomy and Ex-PRESS surgery than in those after tube shunt surgery. The total costs of laser therapies were lower than those of incisional glaucoma surgeries. The total cost was the highest in the 0–19 age group (856,398 [649,419–1,258,844] yen).

CONCLUSIONS

Tube shunt surgery was the costliest in terms of total one-year costs. Trabeculectomy and Ex-PRESS surgery were associated with long hospital stays and incurred high postoperative costs. The costs of laser therapies were relatively low. However, cost-effectiveness of laser therapies compared with incisional surgeries needs to be analyzed in future research.

BACKGROUND

Administrative claims databases are increasingly being used worldwide for research purposes. We reviewed original published articles that used one of the four nationwide administrative claims databases in Japan: the National Database of Health Insurance Claims and Specific Health Checkups (NDB), NDB Open Data, the JMDC Claims Database, and the Diagnosis Procedure Combination (DPC) database.

METHODS

Studies published from January 2010 to July 2022 using the JMDC and DPC databases, and from January 2013 to July 2022 using the NDB and NDB Open Data were identified using PubMed. The number of original articles was divided into 19 fields. The annual growth rate of the number of studies was calculated using the four databases.

RESULTS

Overall, 1047 studies were included (95 for the NDB, 31 for the NDB Open Data, 222 for the JMDC database, and 699 for the DPC databases). Studies using one of these four databases increased from around 2010, and the average annual growth rate was approximately 41% from 2010 to 2021. DPC database studies had a higher proportion of articles on surgery (19.2%), urology (3.0%), neurosurgery (6.2%), anesthesiology (1.9%), and emergency medicine (14.0%), whereas the NDB and JMDC data had higher proportions of those regarding internal medicine.

CONCLUSIONS

Since 2010, these four databases have increasingly attracted attention, and the number of studies using them has grown rapidly. Our review suggests that each has unique features, and researchers should understand the database characteristics to operate their studies.