Cardiovascular risk factors and TIA characteristics in 19,872 Swedish TIA patients.

BACKGROUND

Transient ischemic attack (TIA) constitutes a major risk factor for stroke, making TIA patients an important group for secondary intervention. The aim of this study was to account for risk factor prevalence in TIA patients and analyze the association between TIA characteristics and risk factors.

METHODS

We included 20,871 TIA events in 19,872 patients who were registered in the Swedish Riksstroke registry during the years 2010 through 2012. Data from other Swedish registers were used for comparison. The following variables were analyzed: age, sex, diabetes mellitus, atrial fibrillation (AF), cigarette smoking, and antihypertensive treatment.

RESULTS

Compared to the general population (based on data retrieved from Sweden's national public health survey 'Health on equal terms'), TIA patients more often had diabetes mellitus (prevalence ratio, PR = 2.3), AF without oral anticoagulants (OAC) (PR = 2.8), and AF on OAC (PR = 1.6). Blood pressure medication was less prevalent among TIA patients than in the general population (PR = 0.57). Increasing age was associated with longer attacks.

CONCLUSIONS

The fact that diabetes mellitus, atrial fibrillation, and smoking are more common in TIA patients than in the general population suggests that these factors are risk factors for TIA, even if causal relations cannot be proven. The relation between increasing age and longer attacks possibly reflects an increased proportion of embolic TIAs, or impaired recovery ability. Our results also suggest a significant proportion of untreated hypertension cases in the population.