Risk of Repeated Adverse Effects following Booster Dose of mRNA COVID-19 Vaccine: Results from the MOSAICO Study.

The successful deployment of safe and effective vaccines against coronavirus disease 2019 (COVID-19) has been crucial in reducing the global disease burden. Owing to the need for vaccination series over time, continuous observational studies are needed to estimate the COVID-19 vaccine response in real-world conditions. In particular, the detection, assessment, and understanding of adverse effects following immunization (AEFI) with a COVID-19 vaccine are crucial to better address vaccination strategies. Therefore, this study aimed to investigate the risk of repeated AEFI post-administration of a booster dose of mRNA COVID-19 vaccine in a sample of healthcare workers (HCWs) in an Italian teaching hospital. The data on any local and systemic AEFI were studied in multivariate Poisson regression analyses to model the association between the incidence of each postvaccination symptom and its prior reporting after the administration of the previous doses. Overall, compared with the primary vaccination series, the majority of post-third dose AEFI were less reported. The results from multivariable models showed that the likelihood of reporting an AEFI after the third dose was higher in those who experienced the same postvaccination symptom after the second dose (all AEFI except for itch at injection site) and, although not significant for all AEFI, after the first dose. Any associations with age, gender, smoking habits, previous SARS-CoV-2 infection and other characteristics, as well as the health impact of AEFI were also assessed. Taken together, the results from this research support reframe AEFI symptoms as signals of a robust postvaccination reaction as well as of common vaccine response, and they add important data to inform booster vaccination strategies in HCWs and, extensively, in the adult population.

Statins Use in Patients with Cardiovascular Diseases and COVID-19 Outcomes: An Italian Population-Based Cohort Study.

BACKGROUND: The role of statins among patients with established cardiovascular diseases (CVDs) who are hospitalized with COVID-19 is still debated. This study aimed at assessing whether the prior use of statins was associated with a less severe COVID-19 prognosis. METHODS: Subjects with CVDs infected with SARS-CoV-2 and hospitalized between 20 February 2020 and 31 December 2020 were selected. These were classified into two mutually exclusive groups: statins-users and non-users of lipid-lowering therapies (non-LLT users). The relationship between statins exposure and the risk of Mechanical Ventilation (MV), Intensive Care Unit (ICU) access and death were evaluated by using logistic and Cox regressions models. RESULTS: Of 1127 selected patients, 571 were statins-users whereas 556 were non-LLT users. The previous use of statins was not associated with a variation in the risk of need of MV (Odds Ratio [OR]: 1.00; 95% Confidence Intervals [CI]: 0.38-2.67), ICU access (OR: 0.54; 95% CI: 0.22-1.32) and mortality at 14 days (Hazard Ratio [HR]: 0.42; 95% CI: 0.16-1.10). However, a decreased risk of mortality at 30 days (HR: 0.39; 95% CI: 0.18-0.85) was observed in statins-users compared with non-LLT users. CONCLUSIONS: These findings support the clinical advice for patients CVDs to continue their treatment with statins during SARS-CoV-2 infection.

Azithromycin use and outcomes in patients with COVID-19: an observational real-world study.

OBJECTIVES: Previous studies ruled out the benefits of azithromycin for treatment of patients with COVID-19 who are hospitalized. However, the effects of azithromycin for treatment of patients with positive SARS-CoV-2 test results in the community remains a matter of debate. This study aimed to assess whether azithromycin, when used in subjects with positive test results for SARS-CoV-2, is associated with a reduced risk of hospitalization, in-hospital COVID-19 outcomes, and death. METHODS: Two study cohorts were selected. Cohort A included subjects with positive test results for SARS-CoV-2 between February 20, 2020 and December 10, 2020; cohort B included subjects infected with SARS-CoV-2 and hospitalized between February 20, 2020 and December 31, 2020. We compared the risk of hospitalization, intensive care unit access, need for mechanical ventilation, and death in azithromycin users versus nonusers. A clustered Fine-Gray analysis was employed to assess the risk of hospitalization; logistic and Cox regressions were performed to assess the risk of intensive care unit access, mechanical ventilation, and death. RESULTS: In cohort A, among 4861 azithromycin users and 4861 propensity-matched nonusers, azithromycin use was associated with higher risk of hospitalization (hazard ratio [HR] 1.59, 95% confidence interval [CI] 1.45-1.75) compared with nonuse. In cohort B, among 997 subjects selected in both groups, azithromycin use was not significantly associated with intensive care unit access (odds ratio [OR] 1.22, 95% CI 0.93-1.56), mechanical ventilation (OR 1.30, 95% CI 0.99-1.70), 14-day mortality (HR0.88, 95% CI 0.74-1.05), or 30-day mortality (HR 0.89, 95% CI 0.77-1.03). CONCLUSION: Our findings confirm the lack of benefits of azithromycin treatment among community patients infected with SARS-CoV-2, raising concern on potential risks associated with its inappropriate use.

Time-Varying Effect of Hybrid Immunity on the Risk of Breakthrough Infection after Booster Dose of mRNA COVID-19 Vaccine: The MOSAICO Study.

This longitudinal observational study investigated the risk of breakthrough SARS-CoV-2 infection up to 6 months after a booster dose of an mRNA COVID-19 vaccine in infection-naïve vs. previously infected healthcare workers (HCWs), and whether this difference varied over time. A Cox proportional hazard regression model with Aalen's additive analysis was fitted to examine the association between the risk of infections and predictor variables. Overall, we observed an incidence rate of 2.5 cases per 1000 person-days (95% confidence interval [CI] 2.0-3.0), which dropped at 0.8 per 1000 person-days (95% CI 0.3-2.0) in recipients with prior SARS-CoV-2 infection. The fitted analysis indicated an adjusted hazard ratio of 0.32 (95% CI 0.13-0.80; p-value = 0.01) for those with hybrid immunity with a slope that became steeply negative roughly starting from day 90. No difference was seen according to participants' smoking habits. Characteristics of infected HCWs were also described. Our study quantifies the time-varying effects of vaccine-induced and hybrid immunity after the booster dose (during the Omicron variant predominance in Italy) and observed that the protection waned more rapidly in infection-naïve recipients starting from the third month. The results add important evidence that can be used to inform COVID-19 vaccination strategies.

Antidepressants Drug Use during COVID-19 Waves in the Tuscan General Population: An Interrupted Time-Series Analysis.

In Italy, during the COVID-19 waves two lockdowns were implemented to prevent virus diffusion in the general population. Data on antidepressant (AD) use in these periods are still scarce. This study aimed at exploring the impact of COVID-19 lockdowns on prevalence and incidence of antidepressant drug use in the general population. A population-based study using the healthcare administrative database of Tuscany was performed. We selected a dynamic cohort of subjects with at least one ADs dispensing from 1 January 2018 to 27 December 2020. The weekly prevalence and incidence of drug use were estimated across different segments: pre-lockdown (1 January 2018-8 March 2020), first lockdown (9 March 2020-15 June 2020), post-first lockdown (16 June 2020-15 November 2020) and second lockdown (16 November 2020-27 December 2020). An interrupted time-series analysis was used to assess the effect of lockdowns on the observed outcomes. Compared to the pre-lockdown we observed an abrupt reduction of ADs incidence (Incidence-Ratio: 0.82; 95% Confidence-Intervals: 0.74-0.91) and a slight weekly decrease of prevalence (Prevalence-Ratio: 0.997; 0.996-0.999). During the post-first lockdown AD use increased, with higher incidence- and similar prevalence values compared with those expected in the absence of the outbreak. This pandemic has impacted AD drug use in the general population with potential rebound effects during the period between waves. This calls for future studies aimed at exploring the mid-long term effects of this phenomenon.

Impact of COVID-19 Lockdown, during the Two Waves, on Drug Use and Emergency Department Access in People with Epilepsy: An Interrupted Time-Series Analysis.

BACKGROUND: In 2020, during the COVID-19 pandemic, Italy implemented two national lockdowns aimed at reducing virus transmission. We assessed whether these lockdowns affected anti-seizure medication (ASM) use and epilepsy-related access to emergency departments (ED) in the general population. METHODS: We performed a population-based study using the healthcare administrative database of Tuscany. We defined the weekly time series of prevalence and incidence of ASM, along with the incidence of epilepsy-related ED access from 1 January 2018 to 27 December 2020 in the general population. An interrupted time-series analysis was used to assess the effect of lockdowns on the observed outcomes. RESULTS: Compared to pre-lockdown, we observed a relevant reduction of ASM incidence (0.65; 95% Confidence Intervals: 0.59-0.72) and ED access (0.72; 0.64-0.82), and a slight decrease of ASM prevalence (0.95; 0.94-0.96). During the post-lockdown the ASM incidence reported higher values compared to pre-lockdown, whereas ASM prevalence and ED access remained lower. Results also indicate a lower impact of the second lockdown for both ASM prevalence (0.97; 0.96-0.98) and incidence (0.89; 0.80-0.99). CONCLUSION: The lockdowns implemented during the COVID-19 outbreaks significantly affected ASM use and epilepsy-related ED access. The potential consequences of these phenomenon are still unknown, although an increased incidence of epilepsy-related symptoms after the first lockdown has been observed. These findings emphasize the need of ensuring continuous care of epileptic patients in stressful conditions such as the COVID-19 pandemic.

Occupational Exposure in the Lombardy Region (Italy) to SARS-CoV-2 Infection: Results from the MUSTANG-OCCUPATION-COVID-19 Study.

Sero-epidemiological surveys are valuable attempts to estimate the circulation of SARS-CoV-2 in general or selected populations. Within this context, a prospective observational study was conducted to estimate the prevalence and persistence of SARS-CoV-2 antibodies in different categories of workers and factors associated with positivity, through the detection of virus-specific immunoglobulin G and M (IgG/IgM) in serum samples. Enrollees were divided in low exposure and medium-high groups on the basis of their work activity. Antibody responders were re-contacted after 3 months for the follow-up. Of 2255 sampled workers, 4.8% tested positive for SARS-CoV-2 IgG/IgM antibodies, with 81.7% to IgG only. Workers who continued to go to their place of work, were healthcare workers, or experienced at least one COVID-19-related symptom were more likely to test positive for SARS-CoV-2 antibodies. SARS-CoV-2 antibodies prevalence was significantly higher in the medium-high risk vs. low-risk group (7.2% vs. 3.0%, p < 0.0001). At 3-month follow-up, 81.3% of subjects still had antibody response. This study provided important information of SARS-CoV-2 infection prevalence among workers in northern Italy, where the impact of COVID-19 was particularly intense. The presented surveillance data give a contribution to refine current estimates of the disease burden expected from the SARS-CoV-2.