(P-372) Impact of Statin Treatment on COVID-19 Risk and Outcome – a Potential Positive Effect on Survival

Background: Statin treatment has been hypothesized to be protective for virus infections due to its immunomodulatory, anti-inflammatory and membrane rearranging effects. So far, the potential impact of statins on the development and severity of COVID-19 remains unclear.

Objectives: To investigate whether ongoing regular statin exposure may affect risk, severity or outcome of COVID-19 using large linked Swedish population register database (SCIFI-PEARL project).

Methods: A study population, free of COVID-19 on 1 Jan 2020, was obtained by age-sex stratified random sampling from Swedish national population registers including individuals aged 40 and above. People who developed COVID-19 were identified from several sources: positive SARS-CoV-2 polymerase chain reaction (PCR) test results from SmiNet, the national database of notifiable diseases; by condition (ICD-10) codes in the National Patient Register, Cause-of-Death Register; through several disease-specific national quality registers (NQRs); and for one large region also primary care data. Data from all of these registers plus the National Prescribed Drug Register and national sociodemographic registers, were linked to all study subjects. Regular ongoing statin exposure was identified as ≥3 filled prescriptions in the year before index date. Index dates for start of follow-up were 1 Jan 2020, COVID-19 onset (test positive or healthcare encounter), or hospital admission, and follow-up extended until end 2020. Outcomes investigated were COVID-19 test-positivity, onset, hospital admission, ICU admission and death. Cox regression was used to estimate hazard ratios, and confounding factors were addressed by propensity scores including covariates for comorbidities, drug exposures and sociodemographic factors, with inverse probability of treatment weighting (IPTW).

Results: After IPTW, good overlap and balance was achieved between exposed and unexposed (all covariates with SMD≤0.061 in all analyses). In the full study population cohort (n=127545 vs 445178 statin/non-statin), no associations were found between statin exposure and COVID-19 test positivity, COVID-19 onset, hospitalization or ICU admission, but a significant association was found for COVID-19 mortality, HR 0.71 [95%CI 0.63,0.81]. In the COVID-19 onset cohort (n=26242 vs 120364), results were similar – null for hospitalization and ICU, HR 0.81 [0.75,0.87] for mortality; and in the hospitalization cohort (n= 8557 vs 16147) it was null for ICU care and HR 0.86 [0.78,0.94] for mortality.

Conclusions: Statin users appear to have lower mortality from COVID-19 than people who do not use statins.