Heart disease is an important part of the problems of health systems worldwide, which is spreading rapidly in both developed and developing countries and is considered as the most important cause of death(1). The aim of this study was to determine the prevalence of common risk factors for coronary heart disease in the population aged 30-70 years in Yazd.
Results of our study showed that the prevalence of CHD was 8.08%. A study by Ghaemian et al. 2020 estimated the prevalence of CHD in Iran and in the city of Sari to be 9%, which is in line with our study(12). Our results also showed that the highest prevalence of CHD was in older patients especially in the age range of 50 to 60 years and most often in men. So the risk of coronary heart disease was about 6 times higher in people over 60 than those in range of 30-40 years. Ghaemian et al. 2020 showed that the risk of CHD at the age of 60 years was about 10.5 times higher than the age group 40-49 year (12). Kazemi et al. 2017(17), Hedaegh et al. 2009(18), Janghorbani 2006(19), Wong 2018 (20)all acknowledged that aging is directly related to the incidence of CHD.
Consistent with our findings, the 2017 study by Bots et al.(21) showed that the prevalence of disease and mortality was higher in men than women and this difference in prevalence at older ages was significant. Ahmari et al. 2017 in their study in Saudi Arabia also showed that the prevalence of CHD was significantly related to age and gender (22), so that the prevalence of the disease was twice as high in men than women. In other studies that calculated the risk of CHD, men were at higher risk than women (4, 23–25).
The result of Chi-square test in our study showed that the prevalence of the CHD was significantly different in education levels, so that the highest prevalence of the disease was in illiterate people with 17.6%. In 2019, Alquins et al. in study of 2,997 heart patients in Saudi Arabia declared that low education as factors associated with CHD prevalence(23). Nakhaei et al. 2018 in their study on Iranian population emphasized that people with higher education have a lower risk of CHD(16).
Iran's population is changing and aging in the meantime. Diabetes is one of the diseases that is increasing. The results of the study showed that the prevalence of CHD is associated with diabetes. Other studies have acknowledged this (10, 26, 27).
High blood pressure is a major factor in heart disease. STEP 2016 study(28), Nelwan etal. study in 2017(29), which examined cardiovascular risk factors in Indonesia, identified blood pressure as a major risk factor. In the present study, the prevalence of CHD was associated with high blood pressure, so that 22.4% of the prevalence of the disease was seen in people with high blood pressure.
Increased BMI is directly related to the risk of cardiovascular disease (Azarnejad et al. In 2020 stated that high body mass index is the cause of 18.8% of deaths in Iran (10). In the study of Kazemi et al. 2018 in Iran, age, gender and BMI was associated with CHD (17). Other studies have suggested a close association between cardiovascular disease and BMI (13, 14, 30, 31).
The findings of our study showed that there is a significant relationship between family history and the prevalence of CHD. In line with the present study, Wang et al. 2019 examined the risk factors associated with CHD in women and stated that family history is also a risk factor for the disease (20).
The results of MLR in the present study showed that age, education, gender, smoking, LDL-C, family history, diabetes, blood pressure are risk factors for CHD. The odds of getting CHD over the age of 60 was about 6 times than those aged 30-40, in the illiterate people it was about two times than the university education level. Smoking, family history, hypertension and diabetes increased the odds of getting CHD by 1.67, 1.59, 3.48 and 1.64, times than others, respectively. Ghaemian et al. 2020 in the study of factors related to CHD, age, drug use, low physical activity, diabetes, hypertension, abnormal amounts of HDL and LDL and total cholesterol and triglycerides as risk factors for the disease (12). Most studies in the field of CHD agree on the risk factors of age, diabetes, and blood pressure (4, 6, 16, 20, 23). In the present study, these three factors are also among the identified risk factors.
One of the limitations of this study is generalizability because the population studied in this study includes the population of 30 to 70 years in the city of Yazd in central Iran may not be generalizable to the entire population of Iran. Another limitation can be the lack of trust and honesty of the respondents about the questions. To solve this problem, the questioner tried to establish a close relationship with the respondents and assure them that your answers will not be abused in any way.
One of the strengths of this study is the relatively high sample size and many recorded parameters that can provide a good picture of the overall CHD in Yazd. Another advantage of this study was the relatively small amount of missing data, which was minimized by sufficient experience of experts in the study collection phase.