EVALUATION OF METABOLIC SYNDROME IN HEALTHY YEMENI POPULATIONS

The metabolic syndrome is characterized by several cardiovascular risk factors and is associated with an increased incidence of diabetes, cardiovascular events and mortality. The prevalence of metabolic syndrome is increasing in epidemic proportions worldwide. The present study aimed to investigate the prevalence of metabolic syndrome and its components in healthy populations in Sana'a, Yemen. This study was a cross-sectional study conducted from February 2019 to April 2019. A total of 120 healthy populations (40 years≤ old) were selected. The study protocol was approved by the institutional ethical committee and informed consent was obtained from all the enrolled study patients for their inclusion in the screening and participation in the research. In the present study, the diagnosis of metabolic syndrome based on the American Heart Association/National Heart, Lung, and Blood Institute (AHA/NHLBI) and to a joint statement from several large organizations. In the current study, the presence of more than or equal to any three of the above mentioned factors is required for the diagnosis of metabolic syndrome. The total prevalence of metabolic syndrome among the study subjects was 40.0% (P<0.001) and 62.5% of them were within 40-49 years old. In the present study, there was not statically significant difference between the khat chewing and the metabolic syndrome. According the distribution of metabolic syndrome criteria among subjects with metabolic syndrome, the prevalence of fasting blood glucose (FBG) was the highest (85%). The prevalence of metabolic syndrome among healthy Yemeni populations was very high and it is associated with increased morbidity and mortality. This emphasizes the need for more attention to investigate this condition to decreasing the prevalence of cardiovascular morbidity and mortality in these subjects.


INTRODUCTION
Metabolic syndrome was first identified during the late 1980 and was characterized by the clustering of abdominal obesity, elevated blood pressure, hyperglycemia, and dyslipidemia 1 . Subjects with metabolic syndrome are at increased risk for coronary artery disease (CAD), and the present of metabolic syndrome can increase the risk of all new-onset cardiovascular disease (CVD) by 25 % 2 . In addition, metabolic syndrome is associated with an increased risk of death from coronary heart diseases, cardiovascular diseases, and all other causes 3 . Metabolic syndrome increases the risk of type 2 diabetes mellitus and cardiovascular disease (CVD) by a 5-fold and 2-fold, respectively during the next 5 to 10 years 4 . Recently, the prevalence of metabolic syndrome has been reported to be between 10% and 84% globally according to the age, sex, and races of the population 5 . About twenty-five percent of adults in the U.S. have the metabolic syndrome 6 . The prevalence of metabolic syndrome in the Middle East and North African (MENA) region is known for its high, where it has been reported to be 45.5% and 24.3% in Tunisia, using the International Diabetes Federation (IDF) criteria and Adult Treatment Panel (ATP III) definition, respectively 7 . The prevalence of metabolic syndrome in Gulf countries, as part of the Middle East, has shown ranges from 17% in Oman 8 to 40.5% in the United Arab Emirates (UAE) 9 , according to the ATP III and IDF criteria, respectively. According to Al-Rubeaan et al., the prevalence of metabolic syndrome in Saudi Arabia was 39.8% and 31.6% in 2018, depending on the ATP III and IDF criteria 10 . The metabolic syndrome is recognized as a ISSN: 2456-8058 50 CODEN (USA): UJPRA3 significant public-health problem. Due to changes in the social environment, the numbers of people with metabolic syndrome have been increased during the past years. Therefore, the main aim of the current study was to estimate the prevalence of metabolic syndrome and its risk factors among the adult Yemeni population in comparison to other countries.

METHODS
This study was a cross-sectional study conducted from February 2019 to May 2019. A total of 120 of healthy populations (40 years≤ old) were selected. Full ethical clearance was obtained from the qualified authorities who approved the study design and the informed consent was obtained from all the study subjects for their inclusion in the screening and participation in the research.

Figure 1: Prevalence of metabolic syndrome among the study sample among gender and waist circumference
To institute the metabolic syndrome into clinical practice, several scientific organizations have attempted to introduce definition of the syndrome. In the present study, the diagnosis of metabolic syndrome based on the American Heart Association/National Heart, Lung, and Blood Institute (AHA/NHLBI) and to a joint statement from several large organizations 11 . The patients must meet at least three of the following criteria for diagnosis of metabolic syndrome:  In the current study, the presence of more than or equal to any three of the above mentioned factors is required for the diagnosis of metabolic syndrome. Populations with established chronic diseases were excluded to homogenize the study subjects. All the study subjects were personally interviewed by the trained interviewers. The following variables were evaluated: age, sex, waist circumference, HDL cholesterol, triglycerides, fasting glucose, and blood pressure. Statistical analysis was done by SPSS software version 21.0 by using Pearson's Chi-square test. Categorical variables were expressed as percentages. P-value of less than 0.05 was considered significant.

RESULTS
The overall prevalence of metabolic syndrome was 40% (P-value< 0.001), and was significantly higher in women than in men (52.9% vs 30.4%, respectively; P-value=0.01). Out of 69 males, 21 (30.4%) had Metabolic Syndrome and 27 (52.9%) of females had metabolic syndrome (Table 2). There was significantly relationship between the prevalence of waist circumference and metabolic syndrome (P-value<0.001). Twenty six of patients with increased waist circumference had metabolic syndrome, in comparison, 22 of patients with metabolic syndrome did not have increased waist circumference. Table 3 showed the distribution of metabolic syndrome by Triglyceride. Results in this table indicated that the relationship between metabolic syndrome and prevalence of triglyceride was high significant (P-value< 0.001). In addition, out of 48 subjects with metabolic syndrome, 31 of them had high triglyceride. The relationship between metabolic syndrome and HDL cholesterol level was statistically significant (P- value<0.001). According to the study findings, 37(77.1%) of subjects with metabolic syndrome had low HDL (<40 mg/dl in male or <50 in female). However, 11 of subjects with metabolic syndrome had normal HDL cholesterol level. The association between metabolic syndrome and blood pressure was analyzed in the  The study results reported a high prevalence of metabolic syndrome criteria among subjects with metabolic syndrome. The most frequently observed component of metabolic syndrome was found to be Fasting Blood Glucose (FBG), followed by HDL-C (Table 5). According to the study findings, HDL-C had significant relationship between men and women (P-value<0.001). However, there was not statistically significant between men and women in other metabolic syndrome criteria (Table 6).There were not statistically significant between the khat chewing and metabolic criteria. In addition, there were not statistically significant between the metabolic syndrome and khat chewing.

DISCUSSION
Metabolic syndrome is a serious health problem and its prevalence increasing globally. To our knowledge, this is the first Yemeni study that focuses on the estimation of the prevalence of metabolic syndrome in the general population by using the American Heart Association/National Heart, Lung, and Blood Institute (AHA/NHLBI) and to a joint statement from several large organizations. According to the study results, the prevalence of metabolic syndrome was seen in 40 % of the study subjects. This result is consistent with results from other studies, where the prevalence of metabolic syndrome was 38.5% among Americans 12 and of 33.5% in the population of India 13 . However; it is high compared to prevalence in the South African population 14 (25.5%) and lower than that of the population of Nepal (61.7%) 15 . These differences in the prevalence can be explained by the interaction of genetic and environmental factors, which have long been known to play a key role in the pathophysiology of metabolic syndrome 16 . Furthermore, the study of the metabolic syndrome prevalence according to sex showed a significantly higher prevalence in females (52.9%) %) compared to males (30.4%). This result is similar to many studies 17,18 . However, it was in consistent with others where the prevalence is similar between both sexes 19 . Factors such as weight gain after pregnancy, diabetes mellitus during pregnancy, polycystic ovary syndrome, preeclampsia, use of hormonal contraceptives, and menopause may increase the risk of metabolic syndrome in women 20 . In addition, we observed a variation in the prevalence of metabolic syndrome according to age with a maximum at the fourth decade among the study sample (62.5%).This may be related to the most study subjects within this age group (64.2%). A decline was observed in the prevalence of metabolic syndrome in patients aged over 60 years. This may be related to the increase of the mortality in people with metabolic syndrome of >=60 years old. Moreover, the association between premature mortality and the presence of metabolic syndrome has been described in many studies 17, 21 . Also the lack of consensus on metabolic syndromes definitions and the cutoff points used for its components, especially regarding waist circumference, has resulted in these differences. The comparisons between Yemen and other countries must be made with caution. Because in Yemen and most of other studies were conducted in a small area or a city, they cannot be representative of the whole country. Therefore, generalizing the study results to all population is a point of concern 22 . Also the differences between people might to genetic variations that could effect on metabolic syndrome criteria 23 . In terms of individual criteria, the major factors contributing to metabolic syndrome were fasting blood glucose (85%), followed by HDL-C and triglyceride (77.1% and 67.6%; respectively). These findings could be associated with the high prevalence of insulin resistance and the propensity for elevated triglyceride levels in patients with metabolic syndrome. Furthermore, about 34.2% of participants in the sample survey were unaware of preexisting diabetes.

CONCLUSION
In conclusion, this study places Yemen as one of the countries with the highest prevalence of metabolic syndrome. The risk factors for metabolic syndrome in Yemeni populations were similar to those reported internationally. In addition, women were at a greater risk of having metabolic syndrome. The major causes of metabolic syndrome are unhealthy life styles and eating habits. This emphasizes the need for more attention to evaluate this condition to decreasing the prevalence of cardiovascular morbidity and mortality in these subjects. Furthermore, in order to prevent metabolic syndrome, policy makers should consider the promotion of a healthy diet and physical activity in the future strategies of health care of Yemeni population.

AUTHOR'S CONTRIBUTION
The manuscript was carried out, written, and approved in collaboration with all authors.