In summary, we did not find many significant differences between late and early presenting Veterans. Veterans attending some college or vocational school were more likely to present early, however this effect did not hold when adjusting for other variables. Having a STEMI was independently associated with presenting early and reporting ≥2 angina episodes or missing data for the 24
hours prior to hospital admission were independently associated with presenting late. Overall, our findings were both similar and different from what has been found to predict late presentation in the general population.
Our finding that Veterans having a STEMI (vs. NSTEMI) were more likely to present early is consistent with what has been found in the general population
]. Ting et al found that STEMI patients with the shortest delay times had the highest adjusted in-hospital mortality rates
]. These findings suggest that the shortest delays may be an indicator of more severe symptoms and therefore more severe underlying disease. More generally, longer delays are associated with a decreased likelihood for reperfusion therapy and higher mortality rates in STEMI patients
]. For NSTEMI patients, longer delays have not been associated with increased mortality
]. This is encouraging given that 82% of our analytic cohort had an NSTEMI diagnosis. However, because neither patients nor physicians can reliably differentiate between STEMI and NSTEMI without an ECG, and symptoms can manifest very differently for different patients, efforts to decrease delay should be taken for all patients with potential AMI
We also found that Veterans having ≥2 angina episodes or missing data on angina episodes in the 24
hours prior to admission were significantly more likely to present late. This finding is somewhat difficult to interpret given the missing data. For those patients with complete data, having more angina episodes in the previous 24
hours may simply reflect that they had been having the same symptoms for longer. The association of missingness and late presentation may in part be based on the self reported nature of the variable. Veterans who have waited longer to present may be less likely to remember the frequency or duration of their symptoms.
There were several factors associated with late presentation in the general population that were not associated with late presentation among Veterans. These included comorbid conditions and living alone. In a study comparing Veterans with AMI to their Medicare counterparts, Peterson et al. found that Veterans had a higher prevalence of many comorbidities including diabetes and stroke
]. While comorbid conditions have been associated with atypical symptoms of AMI leading to increased delays in studies in the general population
], we did not find such relationships despite Veterans’ higher prevalence of comorbidities. This may be associated with our initial exclusions of Veterans with concurrent noncardiac admission or DNR. In addition, we were somewhat limited in the number of covariates we could include in the model and were therefore not able to examine all potential comorbidities.
Living alone or being single (versus married) has been associated with delayed presentation in the general population especially among men
]. This is of particular concern among Veterans who are predominantly male and may be at a higher risk of living alone due to difficulties forming social attachments or PTSD based on combat experiences
]. Other physical and mental vestiges of military service such as physical disability or substance abuse, may further contribute to self-isolation among Veterans. An estimated quarter to a third of VHA users live alone
]. Despite these concerns, we did not find an association of living alone and late presentation among Veterans. This may be explained in part by findings reported by Guzman et al. that older Veterans who live alone actually have increased outpatient service utilization suggesting that Veterans living alone may seek out social support through health care encounters
]. This finding of increased outpatient service utilization suggests both a risk and a benefit for late presentation among Veterans. The risk is that Veterans living alone may contact or present to their primary care doctor before going to the hospital, further delaying presentation. The benefit however is that more frequent healthcare encounters creates the opportunity for targeted patient education for those at high risk of AMI.
While patient education efforts have had limited success in the general population
], the 2004 VHA patient education intervention known as Time is Life
(TiL) suggests the potential for success among Veterans. The TiL intervention asked providers to distribute educational materials to high risk Veterans during outpatient services. The educational materials promoted development of a survival plan, early recognition of symptoms and calling an ambulance at the first sign of AMI. Of the 4,884 Veterans surveyed, 2,593 responded. Eighty-two percent of respondents said that they never saw the patient education materials. After reviewing the materials, 90% responded that they would call an ambulance if they experienced symptoms of AMI. Personal communication with programdirector Sandra Pineros ofthe VA Puget Sound’sHealth Care System coordinatingcenter, regarding the unpublishedshort communication “An evaluationof a patient educationinitiative in VHA: Timeis Life for HeartAttack”]
Thus, there is evidence that Veterans would be receptive to a targeted patient education intervention. The TiL study also illuminates a system failure to disseminate patient materials during outpatient visits. Future patient education interventions to decrease late presentation among Veterans must have effective strategies in place to avoid such system failures. Focused efforts on dissemination and provider buy-in may help avoid this pitfall with future interventions.
A major limitation of our study is that our research questions and analysis were designed post hoc. In addition, we excluded patients based on several criteria including having a concurrent acute noncardiac condition at admission biasing our cohort towards much healthier patients. The majority of those excluded were early presenters which may have also biased our analysis. In this case, early presentation may be associated with the noncardiac condition for which they were admitted. Participants missing time from symptom onset may have not been able to report or remember the time of symptom onset (based on poor health or length of elapsed time), thus excluding them may have also introduced significant bias. Nearly half of the Veterans in our study were missing information on angina within the prior 24
hours, which may have been a significant predictor of delay if we had complete data. Those participants missing this data were significantly more likely to be late presenters suggesting potential unmeasured confounding. Finally, the self-report nature of our outcome measure may have further been subject to patient recall bias.