not-yet-known not-yet-known not-yet-known unknown The COVID-19 pandemic, caused by SARS-CoV-2, has led to significant global health challenges. This study analyses the dynamics of SARS-CoV-2 variants among patients admitted to Barts Health NHS Trust hospitals using data from the CLIMB-COVID decentralized digital infrastructure allowing precise identification of SARS-CoV-2 variants. A total of 423 patients admitted between October 2020 and March 2021 were included in the study and divided into two groups: the Alpha lineage group, which comprised the B.1.1.7 variant, and the other lineages group, which included all other variants. Whole-genome sequencing of SARS-CoV-2 genomes was conducted using the COVID-CLIMB pipelines. Clinical outcomes, such as mortality rates and deterioration within 28 days, were analysed. To ensure robust findings, analyses were adjusted for confounding factors, including age and comorbidities. Our findings revealed a significant increase in mortality with age for the Alpha lineage and other lineages. The study underscores the importance of age adjustment in clinical studies to accurately assess the impact of different variants. Consistent genomic sequencing and data completeness are crucial for obtaining reliable results and guiding public health responses. These insights are vital for improving patient outcomes and providing a truthful picture of the pandemic, informing both current and future healthcare strategies.