IntroductionNon communicable diseases are the biggest cause of death worldwide. Beside mortality, these diseases also cause high rates of morbidity and disability. Their high prevalence is generally associated to multi-morbidity. Because they need costly prolonged treatment and care, non communicable diseases have social and economical consequences that affect individuals, households and the whole society. They raise the equity problem between and within countries.Methods and limitationsThis annotated bibliography is a systematic review on multimorbidy of non communicable diseases and health equity in WHO Eastern Mediterranean countries. Medline/PubMed, EMBASE and other sources were used to get peer reviewed papers dealing with the review theme. The words/strings used for search and inclusion criteria were: multimorbidity, comorbidity, equity, non communicable diseases, chronic diseases, WHO Eastern Mediterranean and Arab countries.Bibliography with annotationsAccording to the inclusion criteria, 26 papers were included in the present review. Generally, lack or paucity of publications was encountered in themes like headache, cancer and respiratory diseases. Of the 26 contributions selected, twelve dealt with comorbidity of depression and mental disorders with other chronic diseases. Another set of 11 publications was devoted to multimorbidity of diabetes, cardiovascular diseases (CVDs), hypertension, metabolic syndrome and obesity. Considering association of multimorbidity and social determinants, this review shows that female gender, low income, low level of education, old age and unemployed/retired are the most exposed to multimorbidity. It should also be stressed that, geographically, no contribution was issued from North African countries.Non communicable diseases are one of the biggest challenges facing health decision makers in WHO Eastern Mediterranean countries where the multidimensional transition is boosting increases in multimorbidity of depression and mental diseases, cardiovascular diseases, diabetes, cancer and respiratory diseases among the whole population but with the highest burden among the least disadvantaged individuals or subpopulations. Health ministries in WHO Eastern Mediterranean countries should pay a particular attention to the association between equity and multimorbidity and opt for cost effective strategies based on early diagnosis and sensitisation for healthy diet, physical activity, no smoking and no alcohol.

Introduction: Arab populations have many similarities and dissimilarities. They share culture, language and religion but they are also subject to economic, political and social differences. The purpose of this study is to understand the causes of the rising trend of diabetes prevalence in order to suggest efficient actions susceptible to reduce the burden of diabetes in the Arab world. Method: We use principal component analysis to illustrate similarities and differences between Arab countries according to four variables: 1) the prevalence of diabetes, 2) impaired glucose tolerance (IGT), 3) diabetes related deaths and 4) diabetes related expenditure per person. A linear regression is also used to study the correlation between human development index and diabetes prevalence. Results: Arab countries are mainly classified into three groups according to the diabetes comparative prevalence (high, medium and low) but other differences are seen in terms of diabetes-related mortality and diabetes related expenditure per person. We also investigate the correlation between the human development index (HDI) and diabetes comparative prevalence (R = 0.81). Conclusion: The alarming rising trend of diabetes prevalence in the Arab region constitutes a real challenge for heath decision makers. In order to alleviate the burden of diabetes, preventive strategies are needed, based essentially on sensitization for a more healthy diet with regular exercise but health authorities are also asked to provide populations with heathcare and early diagnosis to avoid the high burden caused by complications of diabetes.

BACKGROUND: Diabetes needs costly prolonged treatment and care. Its burden affects the whole society. Six of the top 10 countries with the highest prevalence of diabetes are in the Middle East. Following the studies carried out in Latin America and the Caribbean countries, and in the WHO African region, an estimation of the direct cost of diabetes in the Arab region is proposed. METHOD: Arab countries were classified into three income groups. The prevalence of diabetes was estimated in each country. The direct cost of diabetes included the cost of insulin, oral drugs, reagent strips, urine strips, lancets, glucose meters, laboratory tests, outpatient consultation and hospitalization. To overcome the problem of disparity in prices, three scenarios were used (Low, Medium and High price). RESULTS:The annual average per capita direct cost of diabetes is estimated in US dollars at USD 351, USD 529 and USD 860 according to the low, medium and high cost scenarios, respectively. The cost varies also according to the income group. The annual total direct cost of diabetes in the 21 countries of the Arab world is estimated to be between USD 9 billion and USD 22 billion. The annual average per capita direct cost of diabetes in the Arab region is 1.4 to 3.5 times higher than the average per capita health expenditure of the region (USD 250). The direct cost of diabetes in the third income group is 4.8 to 11.4 higher than the average per capita health expenditure of the group (USD 66.5) whereas, in the first group, the ratio is 0.4 to 1.14. Although indirect cost is not considered in this paper, it is stressed that diabetes also incurs indirect costs due to loss of productivity caused by premature death and disability, and intangible and non-quantifiable costs. CONCLUSION: This study shows that the direct cost of diabetes is high compared to health expenditure in Arab countries. A sincere call is sent to health decision makers to give more importance to sensitisation, early diagnosis and treatment of diabetes.

Diabetes is a chronic disease with a huge and growing socioeconomic burden affecting individuals, families and the whole society. In this paper, we propose an optimal control approach modeling the evolution from pre-diabetes to diabetes with and without complications. We show the existence of an optimal control and then use a numerical implicit finite-difference method to monitor the size of population in each compartment. Our model shows that, using optimal control, the number of diabetics with and without complications can be significantly reduced in a period of 10 years.

Worldwide, diabetes is affecting 370 million people, causing nearly five million deaths and absorbing more than 471 billion USD per year. Mathematical models have been developed to simulate, analyse and understand the dynamics of β-cells, insulin and glucose. In this paper, we consider the effect of genetic predisposition to diabetes on dynamics of β-cells, glucose and insulin. We assume that the β-cell dynamics is governed by the differential equation: