A psychophysical account of patient non-adherence to medical prescriptions. The case of insulin dose adjustment.

AIM: Diabetic patients often do not adjust their insulin doses using the algorithms that they have been taught. While this behavior may intuitively have a number of causes, such as the complexity of the decision or the fear of hypoglycaemia, we propose in this article a more general, "psychophysical", explanation based on behavioral economics concepts used to describe decisions made under uncertainty and risk. The concepts discussed herein may not be familiar to clinicians, who will find here an introduction to theories that may be helpful in understanding some aspects of non-adherence to medical prescriptions.
RESULTS: 1) The Prospect Theory of Kahneman and Tversky proposes that choices made in the context of risk are subject to loss aversion. 2) Decisions under uncertainty use mental short cuts called "heuristics", which can lead to biases; for instance, overestimating the probability of the risk. 3) To understand the very concept of risk, emotions must be considered with a special focus on anticipated regret. 4) Finally, selection difficulty is an important determinant of the preference for the status quo.
CONCLUSION: These concepts may be relevant for understanding a preference for the status quo in decisions made in a context of uncertainty and risk, such as insulin dose adjustment. We suggest that these mental mechanisms may also be involved in other aspects of patients' non-adherence. As other common human behaviors, non-adherence may actually often be a consequence of biases resulting from our ways of thinking, being both cognitive and emotional, and, according to Kahneman, more often "fast" than "slow". Empirical studies are needed to support this hypothesis.