Long-term Cardiovascular Risk of Undiagnosed Chest Pain
Researchers classified chest pain as either diagnosed or undiagnosed at primary consultation.
Most patients with undiagnosed chest pain in primary care do not undergo cardiac diagnostic testing, but have an increased risk of fatal and non-fatal cardiovascular events for at least 5 years, according to a study published in the BMJ.
Kelvin P Jordan, MSc, PhD, from Keele University in the United Kingdom, and colleagues conducted a cohort study to determine the long-term cardiovascular outcomes in patients with undiagnosed chest pain after 6 months of the initial presentation. The study included 172,180 adults with no prior record of cardiovascular disease who were at least 18 years of age from 223 general practices.
Chest pain was classified from medical records as diagnosed (non-coronary condition or angina) or undiagnosed at first consultation. The main outcomes of the study included fatal or non-fatal cardiovascular events during 5.5 years of follow-up. The researchers adjusted for age, sex, deprivation, BMI, smoking status, year of index presentation, and history of diabetes or hypertension or previous prescription for lipid lowering drugs.
The results showed that 72.4% of patients did not have a cause for their chest pain at the index presentation. Of these, 95.2% did not receive any type of cardiovascular diagnosis within the next 6 months. In addition, 2.0% of patients with a non-coronary diagnosis, 11.7% of patients with an unattributed diagnosis, and 31.5% of patients with angina had a recorded cardiac diagnostic investigation during the first 6 months after presentation.
The long-term incidence of cardiovascular events was 4.7% in patients with an unattributed diagnosis compared with 3.0% of patients with an initial diagnosis of non-coronary pain (adjusted hazard ratios [HR] for 0.5 to 1 year after presentation, 1.95; HR for 1 to 3 years, 1.35; HR for 3 to 5.5 years, 1.21).
The researchers note that because of the larger number of patients in the unattributed group, there were more myocardial infarctions in the unattributed group than in the angina group (214 vs 132). Furthermore, patients who had cardiac diagnostic investigations within the first 6 months had a higher long-term risk of cardiovascular events regardless of the initial chest pain diagnosis.
“Prognostic models are needed to identify the patients most at risk, so they can be targeted with specific treatment and lifestyle advice directed at reducing the risk of life threatening cardiovascular events,” the study authors concluded.
Jordan KP, Timmis A, Croft P, et al. Prognosis of undiagnosed chest pain: linked electronic health record cohort study [published online April 3, 2017]. BMJ. doi:10.1136/bmj.j1194