Confidence, Not Just Knowledge: The Psychological Bridge That Gets Heart Patients to Take Their Pills

For millions of people living with coronary artery disease, the difference between a well-managed condition and a life-threatening relapse often comes down to a deceptively simple act: taking prescribed pills every day. Yet medication non-adherence remains one of the most stubborn problems in cardiology, undermining therapeutic goals, driving up morbidity and inflating healthcare costs across the globe. A new study published in Nursing Open suggests that the missing ingredient is not more information but something far more personal — a patient’s belief in their own capability. The research, conducted among 266 patients at a university-affiliated cardiology clinic in northwest Iran, offers a carefully tested psychological model of how empowerment is translated into the daily behaviour of taking medication.

The study, led by researchers at Tabriz University of Medical Sciences, set out to answer a question that has lingered in the chronic disease literature for years: does patient empowerment improve medication adherence directly, or does it work through an intermediate psychological mechanism? Drawing on Social Cognitive Theory, the team hypothesized that cardiac self-efficacy — a patient’s specific confidence in their ability to manage their heart condition, from controlling symptoms to maintaining daily function — serves as the essential bridge between feeling empowered and actually adhering to a medication regimen. The distinction matters enormously for clinical practice, because the two explanations call for very different interventions.

To test the model, the researchers recruited adults with confirmed coronary artery disease attending routine follow-up appointments, excluding anyone who had experienced an acute cardiac event within the previous 30 days. Participants completed three validated instruments: the 25-item Coronary Artery Disease Empowerment Scale, which measures self-determination, emotional self-regulation and personal competence; Sullivan’s 13-item Cardiac Self-Efficacy Scale, covering symptom control and maintaining function; and the widely used 8-item Morisky Medication Adherence Scale. All scales demonstrated good to excellent internal consistency in this sample, with Cronbach’s alpha values ranging from 0.75 to 0.92. The final sample of 266 complete responses exceeded the minimum of 259 participants required by an a priori power analysis.

The participants, whose mean age was 53.56 years and a slight majority of whom were women, were taking an average of just over four cardiovascular medications daily, most commonly antiplatelets, lipid-lowering agents and antihypertensives. Their average adherence score fell in the medium range, a pattern familiar to clinicians everywhere. On average, patients reported a total empowerment score of 97.71 out of a possible 125 and a cardiac self-efficacy score of 50.12 out of 65. Spearman’s correlations confirmed that all three key variables moved together: empowerment, self-efficacy and adherence were each positively and significantly associated with the others, with the strongest link appearing between self-efficacy and adherence.

The statistical heart of the study was a path analysis that modelled the three empowerment sub-dimensions as predictors of the two self-efficacy sub-dimensions, which in turn predicted medication adherence. The model fit the data remarkably well, with a chi-square to degrees of freedom ratio of 1.354, a Comparative Fit Index of 0.998 and a root mean square error of approximation of 0.037 — figures that comfortably exceed conventional thresholds for an excellent-fitting model. Because medication adherence is an ordinal measure, the team also ran a Bayesian estimation using Markov Chain Monte Carlo methods as a sensitivity check; the results were highly comparable, and convergence diagnostics confirmed the stability of the estimates.

The findings were striking in their specificity. Self-determination — the sense of autonomy and personal choice in managing one’s illness — emerged as the strongest predictor of both self-efficacy components, with standardized coefficients of 0.25 for symptom control and 0.33 for maintaining function. Emotional self-regulation also contributed significantly to maintaining function. But the personal competence sub-dimension, which captures knowledge and skills, failed to predict either component of self-efficacy. In other words, simply knowing what to do and how to do it did not build the confidence needed to do it. Bootstrap analysis with 1000 resamples confirmed that the indirect effects of self-determination and emotional self-regulation on adherence, transmitted through self-efficacy, were statistically significant, while the indirect effect of personal competence was not.

Perhaps the most consequential result came from the ordinal logistic regression. When both empowerment and self-efficacy were entered as predictors of adherence, self-efficacy remained a powerful and significant predictor — each one-unit increase in self-efficacy score was associated with a 9 percent increase in the odds of belonging to a higher adherence category — while total empowerment lost its significance entirely. The pattern suggests that the apparent relationship between empowerment and adherence reported in earlier studies may have been an artefact of failing to model self-efficacy simultaneously. Empowerment, in this model, does not act on behaviour directly; it acts by building the belief that action is possible.

This finding carries real theoretical weight. It lends empirical support to a long-standing critique in the empowerment literature, articulated by scholars such as Halvorsen and colleagues, that empowerment is too often reduced to a paternalistic process of transferring knowledge and skills. The Iranian data suggest exactly the opposite: the dimension associated with a genuine redistribution of power — self-determination — was the one that built self-efficacy, while the dimension resembling conventional patient education did not. The result also aligns neatly with Self-Determination Theory, which holds that supporting autonomy is the key to internalising motivation. Notably, the study found a much stronger correlation between empowerment and cardiac-specific self-efficacy than earlier work had found with general self-efficacy, underscoring the value of disease-specific measurement.

The clinical implications are direct. If self-efficacy is the bridge that empowerment must cross to become behaviour, then counselling strategies built purely on information delivery are unlikely to move the needle on adherence. Instead, the authors argue, nurses and other clinicians should deploy techniques that strengthen patients’ sense of autonomy — motivational interviewing, collaborative goal-setting and individualised self-management support. Empowerment-based interventions tested in randomized trials, from haemodialysis units to liver transplant programmes, have already shown that they can raise self-efficacy; this new path model helps explain why they work and which ingredients matter most.

The researchers are careful to acknowledge the limits of their design. The cross-sectional data cannot establish causal direction — successful adherence may itself reinforce self-efficacy over time — and all measures were self-reported, without objective pill counts, pharmacy refill records or clinical biomarkers. The convenience sample from a single referral clinic may not generalise widely, and unmeasured factors such as depression or health literacy could partly explain the observed pathways. Still, the study offers something the field has lacked: an empirically validated, ordered pathway from autonomy to confidence to action, tested in a Middle Eastern population where such models have rarely been examined. Future longitudinal and interventional studies, ideally with objective adherence measures and cross-cultural samples, will be needed to confirm the pathway. For now, the message to cardiology is clear: to get patients to take their pills, stop telling them what to do and start helping them believe they can.

Subject of Research: The mediating role of cardiac self-efficacy in the relationship between patient empowerment and medication adherence in coronary artery disease patients

Article Title: Cardiac Self‐Efficacy Mediates the Relationship Between Patient Empowerment and Medication Adherence: A Path Analysis in Patients With Coronary Artery Disease ‐ Empirical Research Quantitative

Article References: Allahbakhshian, A., Hashempour, F., Saiyadani, S., Sarbakhsh, P., Mohammadnezhad, M., & Radimaher, F. (2026). Cardiac Self‐Efficacy Mediates the Relationship Between Patient Empowerment and Medication Adherence: A Path Analysis in Patients With Coronary Artery Disease ‐ Empirical Research Quantitative. Nursing Open, 13(10), Article e70837. https://doi.org/10.1002/nop2.70837

Image Credits: AI Generated

DOI: 10.1002/nop2.70837

Keywords: coronary artery disease, medication adherence, patient empowerment, cardiac self-efficacy, path analysis, Social Cognitive Theory, self-determination, nursing, patient education, motivational interviewing, chronic disease self-management, Iran