Coronary heart disease mortality increased in Syria by over 60% between 1996 and 2006. These trends resembled those in other developing countries such as China (using the same IMPACT model), as well as India
[14, 59]. Much of this mortality rise can be attributed to adverse trends in major risk factors such as blood pressure, cholesterol and diabetes. This is the first study to examine factors underlying the rise of CHD mortality in Syria. It, therefore, provides important and timely information that could guide national efforts to reduce the burden of CHD in Syria. It also can potentially provide useful information for other comparable Arab countries in the EMR.
The largest fractions of CHD excess mortality paralleled the increases in major CHD risk factors, with almost 60% of the mortality increase being attributable to elevated blood pressure and total cholesterol. These trends are consistent with the overall shift in Arab societies towards urbanization, modernization and lifestyles characterized by unhealthy diet and inactivity. Available data from Syria and other Arab countries in the EMR consistently show dramatic increases in obesity and diabetes, whereby overweight and obesity among adults in the EMR range from 25% to a staggering 82%
. In Syria obesity now affects over half (52%) of adult women
. These unfavourable trends contribute to an adverse cardiovascular risk factors’ profile, including a higher prevalence of diabetes and elevated cholesterol levels, as is seen in this study. The common behavioural roots underlying CVD risk increases in the Syrian population potentially highlight opportunities to reduce mortality rates through population–based interventions promoting healthy eating and active lifestyles. This also emphasizes the need for a national strategy to address non-communicable diseases in Syria using a combination of health promotion, fiscal measures, market controls and community involvement to encourage healthy lifestyles
. The contribution of smoking to increased CHD mortality was modest, as smoking prevalence hardly changed between 1996 and 2006.
This reflects a lack of effective tobacco control policies in Syria, and a complex political situation, where the government agency responsible for tobacco production and sale is much more powerful that the tobacco control unit at the ministry of health.
Modern medical treatments together prevented or postponed 2145 excess deaths in Syria in 2006, equivalent to about one fourth of the total CHD mortality. The biggest contributions came from long-term management of CHD, mainly for secondary prevention, angina, and heart failure. The contributions from surgery and angioplasty were small, accounting for 4% of the mortality reduction. Our previous research in Syria showed that in spite of high prevalence of CHD risk factors, such as hypertension, awareness and, consequently, treatment and control of such conditions tended to be low
. For example, our research has shown that about 40.6% of population aged 18–65 years had hypertension, only 11.8% of them were aware of it, and only 8.6% were under treatment
. For diabetes, which affects 15.6% of population aged 25 years and above in Syria, only 11.2% were diagnosed, and only 16.7% of treated cases had their diabetes controlled adequately
. This modest contribution of medical treatment to reducing CHD mortality points out to a great potential for improvement in this area.
Treatment uptakes were moderate (60%-90%) for relatively cheap drugs, such as aspirin, thrombolytic therapy, and beta blockers, but much lower for more expensive surgical procedures. There was essentially no utilization of coronary artery bypass graft (CABG), primary transcutaneous coronary angioplasty (PTCA), rehabilitation, nor cardiac pulmonary resuscitation (CPR) in the community. In our study, surgical procedures had a very limited role in avoiding CHD deaths, resulting in approximately 100 fewer deaths (≈ 5% of total treatment benefit). This small role may reflect the effects of the high cost of these procedures, the lack of access to specialized care for the general population, the limited availability of expertise and facilities needed to perform such procedures and the underdevelopment of the private and public health insurance sectors--a situation similar to that found in other developing countries, such as China
. This contrasts with the higher uptake in developed countries where, for instance, community resuscitation (i.e. out of health care facilities) reached 48% in England and Wales
, and 50% in New Zealand
The IMPACT modelling in this study used a comprehensive approach, synthesizing data about all major risk factors and all standard treatment options used in the Syrian population between 1996 and 2006. However, this approach also has some limitations. The data used were of variable completeness and quality. We critically appraised the available data to ensure adequate quality for our modeling. For example, we did not rely on national death registry data for causes of death because these were incomplete and of questionable quality, instead, preferring mortality data from WHO estimates
[11, 12]. In addition, when data were not available, we used explicit assumptions including data from a comparable neighboring (Palestinian) population.
It is also perfectly reasonable to present the total deaths to explain as 8,515 deaths (6,370 + 2,145). In which case the 5140 deaths attributable to risk factor changes would represent approximately 60% of the total mortality increase.
Lag times were not formally considered in the model. However, increasing evidence suggests that substantial mortality increases or falls may occur within a few years of risk factor changes
. Furthermore, certain assumptions were needed to fill in the gaps for missing information. For example, for the small group aged 65–74 years where risk factor information was not available we had to make assumptions based on the risk factors levels in the nearest age groups. These assumptions are detailed in the
Additional file 1 and were supported by local expert opinions and literature from the region. All were tested in the sensitivity analysis. However, none of these limitations are expected to influence the validity of our main results, as the IMPACT model used in this study was developed to deal with such data problems.