Mehdi Jafari Oori - Department of Nursing, University of Social Welfare and Rehabilitation Sciences, Tehran, Iran
Farahnaz Mohammadi - Associate Professor, Iranian Research Center on Aging AND Department of Nursing Education, University of Social Welfare and Rehabilitation Sciences, Tehran, Iran
Kian Norouzi-Tabrizi - Associate Professor, Department of Nursing, University of Social Welfare and Rehabilitation Sciences, Tehran, Iran
Masoud Fallahi-Khoshknab - Professor, Department of Nursing, University of Social Welfare and Rehabilitation Sciences, Tehran, Iran
Abbas Ebadi - Professor, Behavioral Sciences Research Center, Lifestyle Institute, School of Nursing, Baqiyatallah University of Medical Sciences, Tehran, Iran

BACKGROUND: Medication adherence (MA) has a crucial role in controlling of hypertension (HTN). A difference was observed in the prevalence of anti-hypertensive MA reported in different studies in Iran, so we aimed to determine the overall prevalence of MA.METHODS: Using the English and Persian keywords extracted from Mesh, the databases of MagIran, Barakat Knowledge Network System, Scientific Information Database (SID), Web of Sciences, PubMed, Science Direct, and Google Scholar were reviewed from ۲۰۰۰ to ۲۰۱۸. The overall prevalence of MA was estimated using Random effect mode. The I۲ and Egger’s tests were used to assess heterogeneity and publication bias, respectively. Meta-regression and subgroup analysis were conducted based on variables such as age, marital status, regions, and tools.RESULTS: The overall prevalence of MA was ۳۳%. Moreover, the prevalence of MA based on ‎the ۸-Item Morisky Medication Adherence Scale‎ (MMAS-۸), Hill-Bone Medication Adherence (HBMA) scale, researcher-made tools, and self-care tools, were ۱۳%, ۳۴%, ۴۸%, and ۴۷%, respectively. A higher MA prevalence (۳۸%) was observed among older adults compared to other age groups, and married patients (۳۲%) compared to single (۲۳%) individuals. The highest MA prevalence (۵۰%) was related to region ۵ of the country. Meta-regression results showed a significant relationship between the used tools and MA prevalence.CONCLUSION: The overall prevalence of MA is low in Iran. Furthermore, MA was measured using different questionnaires, such as standard international scales and researcher-made tools. It is proposed that a standard international questionnaire should be used in future studies. 

Medication Adherence, Prevalence, Hypertension, Systematic Review, Meta-Analysis, Iran