Believing You Control Your Health May Shape How Well People Manage Diabetes

Why do some people with diabetes meticulously count carbohydrates, test their blood sugar, and never miss a medication dose, while others with the same disease and the same access to care struggle to keep up with even the basics of self-management? A new study from Saudi Arabia suggests that part of the answer may lie not in the pancreas but in the mind — specifically, in what psychologists call health locus of control, the degree to which a person believes that their health outcomes are governed by their own actions, by powerful figures such as physicians, or simply by chance and fate. The research, published in BMC Endocrine Disorders, offers a technically detailed picture of how these belief systems translate into daily diabetes self-care, and it identifies illness perceptions as a critical bridge between what people believe and what they actually do.

The study was led by Majed M. Aljabri, Alya Alghamdi, and Bandar S. Alharbi, researchers in the Community and Psychiatric Mental Health Nursing Department at the College of Nursing, King Saud University in Riyadh. The team recruited 413 adults with diabetes who were attending primary healthcare centers in the Saudi capital. Roughly one-third of the participants — 31.0 percent — had lived with diabetes for more than a decade, and just over a quarter, 26.9 percent, reported experiencing diabetes-related complications, a reminder that the cohort included many people for whom the stakes of good self-care were already painfully concrete. Ethical approval was obtained from the Research Ethics Committee of King Saud University, and the study was conducted in accordance with the principles of the Declaration of Helsinki, with informed consent from all participants.

To capture the psychological dimensions of the problem, the researchers deployed three well-established instruments. The 18-item Multidimensional Health Locus of Control Scale, or MHLC, breaks health-related beliefs into distinct components: Internal Health Locus of Control, reflecting confidence in one’s own agency; Powerful Others Health Locus of Control, reflecting reliance on healthcare professionals and other authority figures; and Chance or Fate Health Locus of Control, reflecting the sense that health outcomes are determined by luck or destiny. Illness perceptions were measured with the Brief Illness Perception Questionnaire, which probes how patients understand their condition — its consequences, its timeline, its controllability, and the emotional weight it carries. Self-care behavior was assessed with the Summary of Diabetes Self-Care Activities, a validated measure covering domains such as diet, exercise, blood glucose testing, foot care, and medication adherence.

The analytical strategy unfolded in two stages, each answering a different question. First, the team used multivariable linear regression to ask whether each locus-of-control dimension was associated with diabetes self-care after statistically adjusting for sociodemographic and clinical characteristics — a crucial step, because raw correlations between beliefs and behavior can easily be distorted by age, education, disease duration, or the presence of complications. Second, the researchers turned to structural equation modeling, a statistical framework that allows investigators to test hypothesized pathways linking variables simultaneously, including indirect effects that pass through an intermediate variable. Here, the intermediate variable was positive illness perception, and the question was whether locus of control influences self-care directly, or whether it works by first shaping how patients mentally frame their disease.

The regression results were striking in their asymmetry. Internal Health Locus of Control showed a positive association with diabetes self-care, with a standardized coefficient of 0.29 and a 95 percent confidence interval running from 0.11 to 0.47. Powerful Others Health Locus of Control was nearly identical in magnitude, with a coefficient of 0.28 and a confidence interval of 0.09 to 0.47. In plain terms, people who believed they controlled their own health, and people who trusted the power of their healthcare providers, both tended to report better self-care. The Chance and Fate dimension, by contrast, showed no significant direct association with self-care at all — a finding that might seem to suggest fatalism is irrelevant to diabetes management, until the structural equation modeling revealed otherwise.

That second stage of analysis is where the study becomes genuinely illuminating. Internal Health Locus of Control was strongly and positively associated with positive illness perceptions, with a coefficient of 0.620 and a p-value below 0.001. Positive illness perceptions, in turn, were strongly associated with better diabetes self-care, with a coefficient of 0.506, again at p below 0.001. When the researchers traced the indirect pathway — from internal control beliefs, through more constructive perceptions of the illness, to self-care behavior — the indirect effect was 0.314, with a confidence interval of 0.126 to 0.502 that excluded zero. In other words, a substantial share of the relationship between believing in one’s own agency and actually practicing good self-care appears to run through the way patients conceptualize their disease: how controllable they judge it to be, how serious they consider its consequences, and how coherent their understanding of it feels.

Perhaps the most unexpected result concerned the Chance and Fate dimension. Although fatalistic beliefs showed no direct link to self-care in the regression models, the structural equation model detected a significant indirect association: the pathway from Chance Health Locus of Control through positive illness perceptions to self-care carried a coefficient of 0.113, with a confidence interval of 0.025 to 0.201. This suggests that the relationship between fatalism and diabetes behavior is more nuanced than a simple negative correlation. The authors concluded that Internal and Chance dimensions of health locus of control are associated with self-care primarily through their relationships with illness perceptions, whereas the Powerful Others dimension showed a direct association with self-care behavior — implying that trust in clinicians may motivate action more immediately, without needing to first reshape how the patient views the disease.

The clinical implications of this pathway analysis are considerable. Diabetes self-care is the foundation of glycemic control and the primary defense against the long-term complications that make diabetes one of the world’s most burdensome chronic diseases — retinopathy, nephropathy, neuropathy, and cardiovascular disease among them. Yet self-care is notoriously difficult to change through education alone. If the Saudi findings generalize, interventions that target illness perceptions — for example, helping patients develop a more coherent and controllable mental model of their diabetes — could unlock self-care improvements that information-only programs fail to achieve. The results also hint that different patients may need different psychological levers: those with strong internal control beliefs might benefit most from perception-focused work, while those who defer heavily to their doctors may respond well to structured clinical support and clear, actionable guidance from trusted providers.

The study’s context matters as well. Saudi Arabia faces a substantial and growing diabetes burden, and primary healthcare centers in Riyadh serve a diverse population in which cultural and religious framings of health and destiny can shape how illness is understood. The cross-sectional design, however, imposes an important limitation: because beliefs, perceptions, and behaviors were all measured at a single point in time, the analysis cannot prove that locus of control causes illness perceptions, or that illness perceptions cause self-care. Reverse pathways — in which successful self-management fosters a stronger sense of control, for instance — remain plausible, and longitudinal or interventional studies will be needed to establish directionality. The authors also relied on self-report instruments, which are vulnerable to social desirability and recall bias, although all three scales are widely validated in diabetes research.

Even with those caveats, the research adds a compelling piece to the psychology of chronic disease management. It suggests that the mind’s model of an illness is not merely a passive reflection of medical facts but an active mechanism that converts belief into behavior. For the 413 adults in Riyadh who participated, and for the hundreds of millions of people worldwide living with diabetes, the message is that how you think about your disease — whether you see it as manageable, coherent, and within your influence — may matter almost as much as the medications in your cabinet. And for the clinicians treating them, the study argues that listening to how patients perceive their illness could be as clinically productive as prescribing the next dose.

Subject of Research: Health locus of control, illness perceptions, and diabetes self-care among adults with diabetes in Saudi Arabia

Article Title: Associations of health locus of control with diabetes self-care: the role of illness perceptions among adults with diabetes in Saudi Arabia

Article References: Aljabri, M. M., Alghamdi, A., & Alharbi, B. S. (2026). Associations of health locus of control with diabetes self-care: the role of illness perceptions among adults with diabetes in Saudi Arabia. BMC Endocrine Disorders. https://doi.org/10.1186/s12902-026-02567-6

Image Credits: AI Generated

DOI: 10.1186/s12902-026-02567-6

Keywords: diabetes, health locus of control, illness perceptions, diabetes self-care, self-management, health psychology, structural equation modeling, Saudi Arabia, primary health care, chronic disease, patient behavior, endocrinology