Aims/hypothesisTo provide a systematic overview of the current body of evidence on high-risk phenotypes of diabetes associated with COVID-19 severity and death.MethodsThis is the first update of our recently published living systematic review and meta-analysis. Observational studies investigating phenotypes in individuals with diabetes and confirmed SARS-CoV-2 infection with regard to COVID-19-related death and severity were included. The literature search was conducted from inception up to 14 February 2022 in PubMed, Epistemonikos, Web of Science and the COVID-19 Research Database and updated using PubMed alert to 1 December 2022. A random-effects meta-analysis was used to calculate summary relative risks (SRRs) with 95% CIs. The risk of bias was evaluated using the Quality in Prognosis Studies (QUIPS) tool and the certainty of evidence using the GRADE approach.ResultsA total of 169 articles (147 new studies) based on approximately 900,000 individuals were included. We conducted 177 meta-analyses (83 on COVID-19-related death and 94 on COVID-19 severity). Certainty of evidence was strengthened for associations between male sex, older age, blood glucose level at admission, chronic insulin use, chronic metformin use (inversely) and pre-existing comorbidities (CVD, chronic kidney disease, chronic obstructive pulmonary disease) and COVID-19-related death. New evidence with moderate to high certainty emerged for the association between obesity (SRR [95% CI] 1.18 [1.04, 1.34],n=21 studies), HbA1c(53–75 mmol/mol [7–9%]: 1.18 [1.06, 1.32],n=8), chronic glucagon-like peptide-1 receptor agonist use (0.83 [0.71, 0.97],n=9), pre-existing heart failure (1.33 [1.21, 1.47],n=14), pre-existing liver disease (1.40 [1.17, 1.67],n=6), the Charlson index (per 1 unit increase: 1.33 [1.13, 1.57],n=2), high levels of C-reactive protein (per 5 mg/l increase: 1.07 [1.02, 1.12],n=10), aspartate aminotransferase level (per 5 U/l increase: 1.28 [1.06, 1.54],n=5), eGFR (per 10 ml/min per 1.73 m2increase: 0.80 [0.71, 0.90],n=6), lactate dehydrogenase level (per 10 U/l increase: 1.03 [1.01, 1.04],n=7) and lymphocyte count (per 1×109/l increase: 0.59 [0.40, 0.86],n=6) and COVID-19-related death. Similar associations were observed between risk phenotypes of diabetes and severity of COVID-19, with some new evidence on existing COVID-19  vaccination status (0.32 [0.26, 0.38],n=3), pre-existing hypertension (1.23 [1.14, 1.33],n=49), neuropathy and cancer, and high IL-6 levels. A limitation of this study is that the included studies are observational in nature and residual or unmeasured confounding cannot be ruled out.Conclusions/interpretationIndividuals with a more severe course of diabetes and pre-existing comorbidities had a poorer prognosis of COVID-19 than individuals with a milder course of the disease.RegistrationPROSPERO registration no. CRD42020193692.Previous versionThis is a living systematic review and meta-analysis. The previous version can be found athttps://link.springer.com/article/10.1007/s00125-021-05458-8FundingThe German Diabetes Center (DDZ) is funded by the German Federal Ministry of Health and the Ministry of Culture and Science of the State North Rhine-Westphalia. This study was supported in part by a grant from the German Federal Ministry of Education and Research to the German Center for Diabetes Research (DZD).Graphical AbstractSupplementary InformationThe online version contains peer-reviewed but unedited supplementary material available at 10.1007/s00125-023-05928-1.