A 2021 CDC report on 378,048 US deaths attributed to COVID-19 identified a co-occurring diagnosis of chain-of-event condition (COE) (e.g., pneumonia, respiratory failure), or significant contributing condition (SCC) (e.g., diabetes, dementia), or both; in 91.9% of the patients. This study assessed the prevalence of comorbid COE and/or SCC among diagnosed COVID-19 patients in a large open-source US claims database. Patients with any claim including COVID-19 diagnosis in IQVIA’s longitudinal medical and pharmacy claims databases from 4/1/2020 to 4/30/2022 were identified. Among these COVID-19 patients, presence of a COE diagnosis (within +/- 7d of COVID-19 diagnosis) or history of SCC, or both, were identified. Within this subset, patients with no subsequent claims activity > 30 days after the last COVID-19 diagnosis were flagged. Flagged patients were linked to Veritas database containing >33 million death records. Among the 17,682,111 patients with any claim for COVID-19, acute respiratory failure (7.4%), pneumonia (5.1%) and asphyxia (4.7%) were the most common COE conditions. Essential hypertension (36.5%) was the most common SCC, followed by hyperlipidemia (22.5%), obesity (19.7%) and type 2 diabetes (19.1%). Overall, 970,324 patients were flagged with COE and/or SCC and no subsequent claims activity >30 days after the last COVID-19 diagnosis; of those, 34.6% patients aged 65-75 and 42.4% aged >75 years had a death flag in Veritas data. The prevalence of metabolic SCC is high among patients treated for COVID-19 in the US. Concurrent COE/SCC and an end of claims activity within 30 days was associated with over a third of deaths among elderly patients. The findings from this study could be used in combination with other known risk factors for poor outcomes among COVID-19 patients to identify patients at high risk of mortality.