The association between spinal cord injury and acute myocardial infarction in a nationwide population-based cohort study.

Study Design: A spinal cord injury (SCI) retrospective cohort study was derived from the National Health Insurance Research Database of Taiwan.
Objective: We evaluated risk of acute myocardial infarction (AMI) in patients newly diagnosed with SCI.
Summary of Background Data: According to information of the World Health Organization, cardiovascular diseases are the most frequent causes of death in patients with SCI compared with those in the general population.
Methods: We obtained claims data from the National Health Insurance Research Database for this cohort study. The SCI group comprised 22,197 patients with a diagnosis of SCI. Case and control patients were based on risk-set sampling in a 1:4 ratio, and we excluded patients with a prior diagnosis of AMI. Comorbidities were categorized as the proportion of prior illnesses in the SCI and non-SCI groups. We used the Cox proportion model to explore adjusted hazard ratio (aHR) for developing AMI between case and control patients.
Results: Patients with SCI were significantly more likely to exhibit pre-existing illnesses associated with AMI than patients without SCI. Patients with a diagnosis of SCI exhibited significantly higher aHRs for developing AMI than patients without SCI (aHR=1.17; P<0.05). Patients with SCI, compared with patients without SCI, were associated with a subsequent AMI risk (aHR=1.17; P<0.05). Several comorbidities, such as cardiovascular disease (aHR=1.29; P<0.05), chronic obstructive pulmonary disease (aHR=1.51; P<0.05), hypertension (aHR=1.34; P<0.01), and renal disease (aHR=1.76; P<0.05), were associated with an increased AMI risk. Furthermore, T-spine SCI was significantly associated with an AMI risk (aHR=1.38; P<0.05).
Conclusion: Patients with as diagnosis of SCI exhibited an increased risk of AMI compared with patients without SCI. These findings have broad implications for surveillance among patients with SCI, and future studies should evaluate whether risk factor modification can decrease AMI risk among patients with SCI.
Level of Evidence: 3.