Journal of Health Literacy

Journal of Health Literacy

Metabolic Factors as Mediators of the Association between Health Literacy and Incident Hypertension: Findings from the Shahrekord Persian Cohort Study

Articles in Press

Document Type : Original Article

Authors
Vahid Khosravi 1
Maede Hosseinnia 2
Ali Ahmadi 3
Masoumeh Alidosti 4
Elahe Tavassoli 5
Samaneh Torkian 6
1 PhD, Department of Public Health, Social Determinants of Health Research Center, School of Health, Shahrekord University of Medical Sciences, Shahrekord, Iran.
2 PhD, Child Growth and Development Research Center, Research Institute for Primordial Prevention of Non-Communicable Disease, Isfahan University of Medical Sciences, Isfahan, Iran.
3 Professor, Department of Epidemiology and Biostatistics, School of Health, Shahrekord University of Medical Sciences, Shahrekord, Iran.
4 Assistant Professor, Department of Public Health, School of Health, Shahrekord University of Medical Sciences, Shahrekord, Iran.
5 Associate Professor, Social Determinants of Health Research Center, Shahrekord University of Medical Sciences, Shahrekord, Iran.
6 Assistant Professor, Department of Epidemiology and Biostatistics, School of Health, Shahrekord University of Medical Sciences, Shahrekord, Iran.
10.22038/jhl.2026.96223.1983
Abstract
Background and Objective: Hypertension is a major global health concern, yet the role of health literacy in its development remains unclear, especially in Middle Eastern populations. This prospective cohort study examined the association between health literacy and incident hypertension in southwestern Iran.

Materials and Methods: This cohort study included 4,217 adults aged 35–70 years without baseline hypertension from the Shahrekord PERSIAN Cohort, followed for 7 years. Health literacy was assessed using the HELIA questionnaire, with inadequate literacy defined as below the 25th percentile. Incident hypertension was confirmed through physician diagnosis or antihypertensive medication use. Hierarchical logistic regression estimated odds ratios (ORs) with 95% confidence intervals (CIs), with progressive adjustment for confounders. Causal mediation analyses were conducted using Stata's mediate command.

Results: Participants' mean age was 47.55 ± 8.33 years. During follow-up, 107 incident hypertension cases (2.6%) were recorded. Mediation analyses showed significant indirect effects for triglycerides (27.4%, p = 0.001) and fasting blood sugar (15.6%, p = 0.027), though both fell below the 30% threshold for meaningful mediation, suggesting only partial mediation. These variables were therefore treated as confounders in the final model.
In the crude model, inadequate health literacy was linked to higher odds of hypertension (OR: 1.72, 95% CI: 1.02, 2.90). This association persisted after adjustment for age, ethnicity, BMI, physical activity, and depression (OR: 1.78, 95% CI: 1.02, 3.11). However, with further adjustment for fasting blood sugar and triglycerides, the association became non-significant (OR: 1.67, 95% CI: 0.95, 2.92). In the fully adjusted model, age, obesity, depression, and elevated triglycerides remained independently associated with hypertension.

Conclusion: Triglycerides and fasting blood sugar partially mediated the association between health literacy and incident hypertension. These findings suggest that metabolic factors may lie on the pathway between health literacy and hypertension, though the modest mediation proportions indicate that other pathways also contribute.
Keywords
Health Literacy
Hypertension
Incidence
Cohort Study
Metabolic Factors
Iran

Acknowledgements: The authors would like to thank the participants of the Shahrekord PERSIAN Cohort Study for their valuable contribution. We also acknowledge the staff of the PERSIAN cohort for their dedicated work in data collection and follow-up. We are grateful to the Shahrekord University of Medical Sciences for providing access to the cohort data.


Availability of data and materials: The data supporting the findings of this study are available from the Shahrekord PERSIAN Cohort Study but restrictions apply to the availability of these data, which were used under license for the current study. Data are available from the corresponding author upon reasonable request and with permission of the Shahrekord University of Medical Sciences.


Conflicts of interest: The authors declare that they have no competing interests.


Consent for publication: Not applicable. This manuscript does not contain any individual person's data in any form (including individual details, images, or videos).


Ethics approval and consent to participate: This study was conducted in accordance with the Declaration of Helsinki. The protocol of this study was approved by the Ethics Committee of Shahrekord University of Medical Sciences (approval number: IR.SKUMS.NUMHE.REC.1405.016). All participants provided written informed consent at the time of enrollment into the PERSIAN cohort study. For the present analysis, all data were anonymized before access.


Funding: This study received no specific funding from any funding agency in the public, commercial, or not-for-profit sectors. The Shahrekord PERSIAN Cohort Study was funded by the Ministry of Health and Medical Education of Iran and Shahrekord University of Medical Sciences.


Author Contributions: Vahid Khosravi: Conceptualization, Methodology, Writing – Original Draft, Supervision. Maede Hosseinnia: Investigation, Resources, Methodology, Writing – Review & Editing. Ali Ahmadi: Data curation, Methodology, Validation, Writing – Review & Editing. Masoumeh Alidosti: Investigation, Resources, Writing – Review & Editing. Elaheh Tavasooli:  Methodology, Visualization, Writing – Review & Editing. Samaneh Torkian: Conceptualization, Formal analysis, Methodology, Supervision, Writing – Review & Editing, Project administration. All authors read and approved the final manuscript.


AI Statement: During the preparation of this manuscript, the authors used DeepSeek AI (deepseek.com) for English language editing, literature search, and summarization. After using this tool, the authors reviewed and edited the content as necessary and take full responsibility for the content of the publication. No AI tools were used for data collection, statistical analysis, or drawing scientific conclusions.

 

Open Access Policy: This is an open access article under the terms of the Creative Commons Attribution License, which permits use, distribution and reproduction in any medium, provided the original work is properly cited. To view a copy of this license, visit https://creativecommons.org/licenses/by/4.0/

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Journal of Health Literacy

Articles in Press, Accepted Manuscript
Available Online from 03 October 2026