Limitations
Our study should be reviewed with certain limitations to our analysis. Since we used admission-associated data rather than patient-level data we depended on administrative diagnosis codes. Therefore, the outcomes among the patients who were discharged cannot be defined due to limited information of follow-up. We were also unable to account for unmeasured confounders that could be associated with increased risk of TTS in AIS patients and the complications occurring during hospital stay. Data on medication records and follow-up were not available. Despite these limitations, the benefit of using a large, multi-center, representative sample affords a truly national perspective and preserves the validity of associations reported.