The Prospective Epidemiological Research Studies in IrAN (PERSIAN) is a nationwide cohort study launched in the year 2014, in order to assess the prevalence of the most common chronic diseases in Iran and identify the risk factors associated with them.

The PERSIAN Cohort was designed and executed to tackle the rising incidence of non-communicable diseases (NCD) in Iran. Today, NCDs cause over 80% of deaths in the country, with cardiovascular diseases, neoplasms and diabetes topping the list. While many smaller, isolated studies and cohorts had previously investigated NCDs, a nationwide investigation was needed because of the great diversity in Iranians’ lifestyles, ethnic and cultural practices, as well as social and environmental exposures, which can differently influence disease development.

All major ethnic populations of Iran are included in the PERSIAN Cohort, which also covers a variety of geographical areas such as the humid northern coast, central deserts, mountainous regions and the semi-tropical south, to fully capture the diverse exposures and possible disease risk factors.

The PERSIAN Cohort initially started with the Main Adult Cohorts, enrolling men and women 35-70 years of age through multiple centers. But soon after its successful execution, researchers from various fields showed interest in starting cohorts in other age groups, which gave rise to the launch of the PERSIAN Birth, Youth, Elderly, and Employee Cohorts. While the overall aim of each cohort is assessing factors influencing NCDs, each cohort has specific aims, related to its target population.


The PERSIAN Birth Cohort enrolls pregnant women and follows their newborn infants to investigate the relationship between genetic, environmental and social factors on human development, while the PERSIAN Youth Cohort focuses on psychiatric disorders and substance use among the teen and young adult population. The PERSIAN Elderly Cohort, studies the aging process and the quality of life of older adults, and the PERSIAN Employee Cohort, assesses occupational risk factors of NCDs.

Within the Main Adult cohort, other sub-cohorts such as the PERSIAN Eye Cohort and the PERSIAN Ear Cohort have also been initiated, with a greater focus on eye and ear disorders. The newest cohort joining the PERSIAN Cohorts is the PERSIAN Traffic Safety and Health Cohort, which is of great importance given that traffic accidents cause the highest rate of deaths in Iran, after NCDs.

Today, the PERSIAN Cohort—encompassing 51 cohort centers—is the largest cohort in the Middle East and Northern Africa, with the largest and most comprehensive dataset and biobank.  PERSIAN has encouraged research in the fields of medicine, epidemiology, health, and nutrition, and has empowered medical universities around the country with the necessary resources to take part in the study and conduct high quality research.

The PERSIAN Cohort is an active member of the Asian Cohort Consortium and the International HundredK+ Cohorts Consortium, taking part in international research studies and collaborations.

The ultimate goal of the PERSIAN Cohort, however,—reforming the health system—is still yet to come…