A commentary notes the ASCOT Legacy study is one of the first trials of antihypertensive and lipid-lowering treatment to show long-term beneficial effects persisting beyond the active treatment period. The other large trial of the effects of blood pressure-lowering and lipid-lowering therapy on cardiovascular disease outcomes is the Antihypertensive and Lipid-Lowering to Prevent Heart Attack Trial (ALLHAT).
It adds that a major limitation of the ASCOT Legacy study is the lack of access to post-trial data on non-fatal CVD outcomes or antihypertensive and lipid-lowering medications, making it impossible to attribute any beneficial effects solely to the treatments provided during the active treatment phase. Furthermore, the absence of information on post-trial patient use of ASCOT trial medications prevents the drawing of conclusions about so-called carry-over rather than legacy effects. Lastly, the ASCOT Legacy study only involved UK residents, not the entire ASCOT patient population. It suggests that the findings of the ASCOT Legacy study have important implications for future long-term follow-up studies of clinical trial participants. Its inability to capture non-fatal CVD outcomes of the ASCOT participants after the closure of the active treatment phase points to the need to establish registries to permit long-term assessment of morbidity and mortality in participants involved in RCTs of interventions for CVD. It is noted that the ASCOT investigators have recently had the opportunity to collect data on morbidity outcomes through National Health Service digital. These data will be forthcoming in the next year or so.