Hypoglycemia and Long-Term Cardiovascular Outcomes in Diabetes Mellitus: A Systematic Review of Prognostic Evidence

Hypoglycemia is a frequent complication of glucose-lowering therapy in diabetes mellitus and has been increasingly linked to adverse cardiovascular outcomes. This systematic review aimed to evaluate the association between hypoglycemic episodes and long-term cardiovascular outcomes, including cardiovascular mortality, major adverse cardiovascular events (MACE), and all-cause mortality. A comprehensive search of PubMed/Medical Literature Analysis and Retrieval System Online (MEDLINE), Scopus, and Web of Science was conducted for studies published between January 2000 and December 2024. Randomized trial-derived analyses and observational cohort studies assessing hypoglycemia as an exposure and reporting cardiovascular or mortality outcomes in adults with diabetes were included. Seven studies met the inclusion criteria. Across the included studies, severe hypoglycemia was consistently associated with an increased risk of cardiovascular events and mortality. In contrast, non-severe hypoglycemia showed less consistent associations and appeared to confer risk primarily at higher frequencies. Temporal analyses suggested an elevated risk of adverse outcomes shortly after hypoglycemic episodes, while some studies demonstrated dose-response relationships. However, interpretation remains complex, as hypoglycemia often occurs in patients with higher baseline risk, raising the possibility that it may act as both a contributing factor and a marker of vulnerability. In conclusion, severe hypoglycemia is associated with increased cardiovascular risk and mortality in patients with diabetes. These findings support the importance of individualized glycemic management strategies that minimize hypoglycemia while maintaining effective metabolic control.