The effect of MHT use on LV and LA CMR parameters in fully adjusted models is detailed in Table 3. Use of MHT for ≥ 3 years was associated with a significant reduction in LV end-diastolic volume (123 ml vs 120 ml, effect size = -2.4%, 95% confidence interval [CI]: -4.2% to -0.5%; p = 0.013), LV stroke volume (74 ml vs 72 ml, effect size = -3.1%, 95% CI: -5.1% to -1.0%; p = 0.004) and LA maximal volume (60 ml vs 58 ml, effect size = -4.5%, 95% CI: -7.8% to -1.0%; p = 0.012). These associations remained significant at a false discovery rate of 10%. To further examine these associations produced by complete case analysis, multiple imputation of missing values was performed and the analysis repeated. The same CMR variables demonstrated significant associations with MHT use; these results are detailed in S1 Table.