The PURE-Saudi is the first cohort study in Saudi Arabia that assessed the current prevalence of CVD risk factors, in addition to the long-term clinical outcomes. Being part of the internationally standardized and validated surveys of the global PURE study allows for a valid interpretation and direct comparison of the results in the context of other enrolled countries with variable economic scales and health care systems. Our study showed two major findings. First, the high prevalence of CVD risk factors among the Saudi population: two-thirds had low physical activity, about half had obesity, one third consumed unhealthy diet, about one third had dyslipidemia, about one third had hypertension, and about one quarter had diabetes. Second, the relative proportion of the individual CVD risk factors varies according to age, sex, and residence place.
The PURE-Saudi study confirms that the prevalence of un-healthy life styles and CAD risk factors remains high in the Saudi population despite over a decade of several previous population cross-sectional surveys (Additional Table 4). The Coronary Artery Disease in the Saudis Study (CADISS) was a national epidemiological health survey between 1995 and 2000, and included 17,395 Saudis aged 30-70 years through a multistage stratified cluster sampling technique. The overall prevalence of hypercholesterolemia was 54%, obesity 35.6%, hypertension 26.1%, diabetes 23.7%, and smoking 12.8%. [11-13, 23-25]. Another national cross-sectional survey by the Saudi Ministry of Health involved 4758 participants aged 15 year to 64 year and aimed to estimate the prevalence of some of the risk factors of non‐communicable diseases (NCD) by using the WHO STEPwise approach for NCD surveillance. It indicated that the prevalence of physical inactivity was 67.6%, obesity 36.2%, hypercholesterolemia 19.1%, hypertension 11.6%, diabetes 15.3%, and current daily smoking 10.9%.[14] The Saudi Health Information Survey (SHIS) was done also by the Ministry of Health and enrolled 10,735 Saudis aged 15 years or older in 2013.The prevalence of physical inactivity was 39.8%, obesity 28.7%, daily consumption of < 2 servings of fruits and vegetables 61.6%, hypertension 15.2%, diabetes 13.4%, hypercholesterolemia 8.5%, and smoking 12.1%.[9, 10, 28, 29, 37]. As a result of such high prevalence of the CVD risk factors, patients in Saudi Arabia present almost a decade younger with acute coronary syndromes and acute heart failure compared to those in the developed countries; hence suffer from being at high risk for cardiovascular complications and mortality. [38-40]
Compared to the general population, patients with diabetes are 2 to 4 times more likely to develop CVD. [41]. According to the International Diabetes Federation diabetes Atlas (8th edition), Saudi Arabia is among the top ten countries in the prevalence of diabetes mellitus. [42] It is estimated that the diabetes prevalence will increase by 110% in the Middle East and North Africa (MENA) by 2045. The prevalence of diabetes in PURE Saudi was among the highest levels reported in the global PURE data. Overall, diabetes prevalence was 11%, and the prevalence of diabetes varied between country income groups, where prevalence of diabetes was lowest in HICs 6.6% and highest in low-income countries (LICs) 12.3%. [43]. Moreover, analysis of the global PURE data showed that hypertension prevalence was 40.8%, and that only third of the patients had reached their blood pressure targets.(44) A report of prevalence, awareness, treatment, and control of hypertension from baseline PURE data from four Middle East countries [Iran, Occupied Palestinian Territory (OPT), Saudi Arabia, and United Arab Emirates (UAE)] showed that one-third had hypertension, about half of them were aware and treated, but only one-fifth were controlled.[45] The prevalence of hypertension was highest in UAE (52%) and lowest in Iran (28%), while the awareness, treatment, and control of hypertension were higher in the OPT and Saudi Arabia, compared with UAE and Iran.[45] Other previous national studies reported suboptimal hypertension control in the Saudi population.[7, 24]. Affordability of medications is one of the main reasons for the low rate of hypertension control in the world. [46] However, in Saudi Arabia, healthcare and medications are free of charge, making them largely accessible to the population. Several barriers facing patients, physicians, and healthcare systems pursuing control of hypertension, indicating the need for multifaceted interventions.[47, 48] Forgetting to take medical therapies and medication side effects were important barriers to medication adherence.[48] Analysis data from a large household survey of 10,735 participants to identify barriers to healthcare in Saudi Arabia found that neither distance to nor type of healthcare clinic were barriers to management of chronic diseases, and highlighted the importance to individual’s healthcare seeking practices rather than system based as potential barriers. Possibly that some Saudi population have specific healthcare-seeking practices and they mostly seek healthcare when they are sick and that contradict the concept of an old Arab proverb ‘Prevention is better than treatment’.[49] Lack of primary care physicians knowledge and awareness of hypertension guidelines was also found where one-fourth of 322 primary care physicians had deficient knowledge regarding the correct definition of hypertension.[50] Regarding the healthcare systems barriers, inappropriate coordination between medical sectors has been reported as about one third of Saudi hypertensive patients did not have hypertension file at the primary health care centers and they received medical care at different health care sectors that led to missing their regular appointments.[47].
One of the main findings of PURE Saudi is that women are more obese compared to men. Possible explanation of higher obesity prevalence in women in this cohort may be due to some sociocultural factors and governmental bylaws such as – only until recently- the requirement of women to have a car driver for transportation purposes and barriers to practice physical activities in public places that could lead to increasing prevalence of sedentary lifestyle and obesity in Saudi women. Therefore, increasing accessibility of women to exercise facilities and providing safe walking areas are likely to help to reduce the obesity prevalence. Recently, women gymnasia in Saudi Arabia became more accessible and women were allowed to drive by themselves, which could potentially help in improving access to a healthier lifestyle. On the other hand, the lower rate of diabetes in women than men in our study may attributed to the well-recognized greater willingness of women than men to seek medical advice. [51] In addition, women are also more willing than men to adhere to diabetes daily management such as restricted diet, blood glucose monitoring, and medication adherence. [52]
Another important issue to be highlighted is the common belief that risk of developing CVD is higher in individuals who live in urban areas compared to those in rural areas. [53]. Findings from the global PURE cohort from high-income countries reported that similar INTERHEART risk score among population in rural areas in comparison to urban population. [35] However, the PURE Saudi study showed that population living in rural areas had higher CVD risk factors particularly in the prevalence of diabetes, hypertension and obesity compared to the urban population. Possible reasons might be related to ‘urbanization of rural life’, a term that described by some researchers,[54] where agriculture became mechanized, and cars are used for rural transport, road infrastructure improved, and more consumption of processed carbohydrates and commercially prepared and processed food through national and transnational companies, all of these would contribute to the increase in rural obesity.[55-57] In addition, the limited time and space for cooking healthy meals and possibly perceptions of large weight as a sign of affluence could also exacerbate these effects.[57, 58] Our findings might also reflect less access to and /or low availability of a health care prevention and management facilities in the rural areas. The reason behind these disparities may be due to inconsistent insurance policies, poor healthcare infrastructure and privatization, and accessibility to healthcare facilitates which largely focus on the urban population, leaving the rural population at disadvantage. [59] The higher prevalence of diabetes in rural rather than urban areas provide support for the link between diabetes and lifestyle risk factors (lifestyle changes are less prominent in rural areas). In addition, the lower educational level among rural population as demonstrated in this study may also partly explain the differences in risk factor levels, resembling what was found in the Vasterbotten Intervention Program study in Sweden.[60] For instance, rural population with only primary education level had consistently higher prevalence of hypertension than urban population with higher educational levels.[60] The data form global PURE that assessed socioeconomic status and risk of CVD in 20 low, middle, and high-income countries, education, rather than wealth, was the socioeconomic indicator most consistently associated with outcomes where the major CVD events and all cause morality were more common among people with low levels of education in all types of country studied. However, variances in outcomes between educational levels were not explained by variances in risk factors, which decreased as educational level increased in high-income countries, but increased as educational level increased in low-income countries.(61) Furthermore, results from MONICA study suggested that lower education level among rural population could enhance CVD risk, but causality is difficult to prove.[62]
In the present study, individuals living in urban areas were more prevalent in the consumption of unhealthy diet, sadness and stress. Recent global systematic evaluation of dietary consumption patterns across 195 countries found that improvement of diet prevents one in every five deaths globally and suboptimal diet was responsible for more deaths than other risk factors including smoking, highlighting the urgent need to improve people diet.[63] Urbanization is also associated with factors that could potentially influence the mental health and possibly the development of CVD, such as increased life stressors, overcrowding, higher level of violence, and less social support. [64] However, beside stress caused by transition from rural area to urban area, other cultural factors interplay with urban dynamics might contribute to the development psychological-related problems. Therefore, understanding how cultural dynamics interact with adaptation to urban life may help in appropriate management of mental disorders in cities. [65] Awareness of the negative impact of urbanization on mental health is needed across the Saudi society.
Healthcare is one of the main focus areas of the Saudi Vision 2030 where the Saudi government has initiated radical changes in the structure and function of its health-care system through its National Transformation Program (NTP) to achieve quality care and effective service delivery. In addition, the government has already recognized the importance of the primary prevention of CVD diseases and has announced recently four major projects, which aim to improve people lifestyle. [66-71] Furthermore, the World Heart Federation (WHF) has undertaken an initiative to develop a series of Roadmaps to reduce premature deaths from CVD by at least 25% by 2025. These Roadmaps can be used as guidance for countries toward developing or updating their national NCD programs for the prevention and control of NCD. [72]
There are few limitations of our study. First, the sampling framework of the PURE‐Saudi Study was not nationally representative; hence caution is needed in generalizing our findings to the whole Saudi population. Second, follow-up rates of CVD events and mortality were low, this might be due to short duration of follow-up and the sample size that was relatively small compared to the large population of Saudi Arabia. There are currently ongoing efforts to expand PURE Saudi to a larger population across all areas in the country in order to have meaningful event rates in the follow up. Lastly, we can not exclude the role of genetic predisposition to such high prevalence of CVD risk factors, which could be related to the high consanguinity in the Saudi population. We have reported recently a high prevalence of familial hypercholesterolemia in Saudi Arabia and the rest of the Arabian Gulf countries. [73]
In conclusion, the PURE-Saudi is the first population cohort study in Saudi Arabia. It demonstrated the continued high prevalence of CVD risk factors in the adult Saudi population despite over a decade of several population surveys, and some of these factors were even more prevalent in the rural than the urban population. National awareness programs and multi-faceted health care policy changes are urgently needed to reduce the future burden of CVD risk and mortality.