Qom University of Medical Sciences Journal

Introduction
The rapid increase of population ageing has made it necessary to focus on healthy aging and improving the quality of life (QoL) in old age. Therefore, the concept of “successful aging” has become important in adopting a positive view of aging. Most of studies on successful aging have been conducted in high-income countries whose determinants of successful aging may be different compared to low- and middle-income countries, such as Iran. Therefore, this study aims to identify the frequency of successful aging and the related factors in Tehran city of Iran with the highest number of old people in the country.
Methods
This is a cross-sectional study. Participants were 637 older people aged >60 years in Tehran who were selected using a multi-stage cluster sampling method according to the number of older people in each district. From each district, three neighborhoods were randomly selected. They were divided into two groups of with successful aging and without successful aging based on three components of Rowe and Kahn’s successful aging model including avoidance of disease and disability, maintenance of good physical and cognitive function, and good social engagement. Those who met all three criteria were considered as those with successful elderly. This measure of successful aging was done based on operational definitions that have been made in on previous studies in Iran. In this regard, successful aging refers to not having chronic diseases and disability, being able to perform activities of daily living, count money, and use medications, and having three out of four components of good social engagement.
Results
Based on operational definitions, 42.5% met the first criterion (no disease and disability), 85.1% met the second criterion (good physical and cognitive function), and 45.1% met the last criterion (good social engagement). Only 19.6% had successful aging and 80.4% had unsuccessful aging.
The results of correlation test showed that, among the study factors, only the factor of “living in own house” had no significant relationship with successful aging. The factors of living arrangements, educational level, and age had the highest significant relationship level with successful aging (P<0.001). The results of multiple logistic regression analysis showed that only age, educational level, smoking, and physical activity could significantly predict successful aging. The factors of gender, marital status, living arrangements, employment status, and insurance coverage were removed from the regression model.
Discussion
Consistent with previous studies, the results of this study showed that successful aging in Iran is affected by age, educational level, smoking, and physical activity. Regarding the age factor, the result may be related to the increase of dependency and disability following age. In old age, disability can result in reduced physical activity and mobility. Chronic diseases, especially cardiovascular diseases, also increase in old age, which reduces the QoL. The positive relationship between educational level and successful aging can be due to the fact that higher levels of education lead to better job opportunities and economic state. Education, directly by improving behaviors and healthy lifestyle and indirectly by providing better job opportunities, can lead to fewer disabilities and better economic, social, nutrition and housing conditions, and create a better health-related QoL.
It should be noted that changes in health-related behaviors may take longer to produce significant improvements in successful aging. For example, smoking is harmful and causes many chronic diseases in lone time. Physical activity has also a long-term effect on people’s health and is an important component for successful aging. People who are physically active are more likely to have a healthier lifestyle and avoid smoking or alcohol consumption.
Ethical Considerations
Compliance with ethical guidelines
This study obtained its ethical approval from Iran National Science Foundation (Code:IR.4001970).
Funding
This study was funded by Iran National Science Foundation.


Authors contributions
Conceptualization, writing the initial draft, data collection: Mohammad Sasanipour; Methodology, data analysis, editing & review: Saeedeh Shahbazin.

Conflicts of interest
The authors declare no conflict of interest.
Acknowledgements
The authors would like to thank all participants for their cooperation.