In national survey of adults 40 and older, we found that low education was associated with a 43% greater likelihood of undiagnosed angina. These effects persisted after controlling for age, sex, race, income and having a physician visit in the past year. These findings are consistent with previous studies suggesting that low education may pose an awareness and health communication issue, resulting in possible diagnosis errors and treatment delays.24, 25
To our knowledge, these findings, based on national data using a validated measure for angina symptoms, are novel.
Our data do not indicate why low education is associated with undiagnosed angina symptoms. Our analysis controlled for having had a visit with health care provider within the past year, so having a recent physician visit is unlikely to be the sole explanation. Potentially, this association reflects low patient health literacy and resulting breakdowns in patient-provider communication. There is a strong association between low education and low health literacy.6, 7, 26
Patients with low education are less likely to associate angina symptoms with heart disease.8, 9
Clinicians may not appreciate that patients with low education are describing angina or to clearly communicate their diagnosis to the patients. Physicians often use medical jargon that is poorly understood, particularly by patients with low health literacy.27, 28
Other communication barriers include limited patient knowledge, patient embarrassment regarding asking questions, and suboptimal physician communication behavior.29
When caring for patients with low education, physicians tend to listen less, provide less reassurance, underestimate the information patients desire, fail to engage the patient in shared-decision making, offer patients too little health information, and display less empathy.30, 31
For these reasons, we suspect that our results may reflect communication failures between physicians and their patients with low education.
Other patient demographic characteristics besides low education are also significantly associated with undiagnosed angina. These include being female, Black, and not having seen a physician/health care professional in the past year. Although these reflect post-hoc findings warranting replication through further study, they suggest that clinicians be especially attuned to unrecognized angina among these groups.
Less than 20% of females over the age of 35 are aware that cardiovascular disease is a major cause of death for females.32
The Atherosclerosis Risk in Communities study which used the Rose Questionnaire also revealed higher rates of angina among females compared to males.33
Undiagnosed angina may be attributable to the language used in physician-patient encounters and inaccurate physician beliefs. Females ask more questions than men and try to retrieve more medical information, yet are less likely to be diagnosed as suffering from cardiovascular disease and are more likely to have their symptoms attributed to emotional or psychosomatic causes.34
Despite higher burdens in cardiovascular diseases, Blacks lag behind Whites in cardiovascular disease recognition and awareness.2, 33
Cardiovascular disparities among Blacks are largely attributable to lower educational attainments and more risk factors, particularly hypertension.11
Individuals over 55 years of age were less likely to have undiagnosed angina compared to individuals aged 40–54 years. This may be explained by several factors. Increasing age is associated with greater risk for cardiovascular disease, including angina.2
The association of older age with greater diagnosis likely increases cardiovascular awareness among individuals in this age group. In addition, physicians may also have higher suspicion for angina and cardiovascular diseases in this age group.
Low education is associated with higher risk of developing angina and worse treatment and survival rates for both fatal and nonfatal cardiac events.1
Thus, it is critical for physicians to be cognizant of the communication needs of persons with low education and to employ principles of clear communication, including teach-back.35, 36
Specifically, providers and staff can communicate more effectively with less educated patients through the following steps: providing patients with adequate time and opportunities to voice their concerns and symptoms; showing respect including listening attentively; encouraging the patient to ask follow-up questions; rephrasing complex questions or terms into plain language; using appropriate pictures and graphics to enhance patients’ comprehension of the material being discussed; encouraging the patient to explain their understanding in their own words;37
and actively engaging the patient in decision making.
Health information provided by physicians can be reinforced through public health programs and community outreaches that target persons with low education using simple and informative health messages about cardiac symptoms. Information should also include steps to take if cardiac symptoms occur including contacting emergency medical services immediately.38
Our findings are subject to several limitations. Data are self-reported and potentially subject to recall and reporting bias. No cause and effect can be established due to the nature of the cross-sectional design. We cannot pinpoint where breakdowns in communication occurred. Further study is needed to determine whether higher prevalence of unrecognized angina among those with low education results from patients failing to report symptoms or from clinicians failing to ask and/or recognize symptoms.
Most participants likely completed their formal education more than 20 years ago. However, the effect of educational attainment on literacy persists over time. National data show a similar pattern between years of education and reading ability regardless of age.39
Finally, we cannot exclude the possibility that other factors not accounted for in our model may be confounded with our results.