Obesity prevalence in adults and patients with hepatitis C: results from screening a population of 50 million in Egypt

Obesity is a global health problem and has been increasing in Egypt over the last several decades. A national popu‑ lation screening program for hepatitis C included screening for obesity. Here we report the outcome of body mass index (BMI) calculation for the screened population and for patients with hepatitis C. Methods Adults 18 years and older (a target population of 62.5 million) were invited to participate in a screening program between October 2018 and April 2019. Persons had their BMI calculated. All data were entered in real‑time to a central database via cellular networks. BMI data for patients with hepatitis C virus (HCV) infection before starting direct antiviral therapy were obtained from the National Committee for the Control of Viral Hepatitis (NCCVH) Findings 49.6 million persons (25.6 million females and 24.0 million males) voluntarily participated and had valid height and weight data. 12.7 million females (49.51%) and 7.09 million males (29.53%) were affected by obesity (BMI ≥ 30kg/m 2 ). Obesity increased with age, was more prevalent in females, was more prevalent in the Nile Delta states and in urban areas. Detailed district‑level prevalence for the whole country is identified. Prevalence of obesity among 335,504 patients with HCV was higher in females, increased with age, and was significantly lower overall and in males and females than in the screened general population. Conclusion This is the largest population screening program for obesity. We show that obesity prevalence in the gen‑ eral population is currently among the highest in the world, starting in young adults, and highlight the high preva‑ lence areas. Prevalence is lower in patients with HCV.


Introduction
Obesity is a major health problem, increasing the risk of many diseases including fatty liver disease, type 2 diabetes mellitus, cardiovascular, cerebrovascular, musculoskeletal disorders, Alzheimer's disease, some cancers, and all-cause mortality [1][2][3].Obesity is also a cause of poor quality of life in some instances, due to discrimination, stigmatization, and impact on employment chances.Currently, the World Obesity Federation views obesity as a chronic progressive disease, and not just a risk factor for other diseases [4].
Obesity is increasing globally.The World Health Organization (WHO) estimates that the global prevalence of obesity has tripled between 1975 and 2017 [5].In Egypt, the prevalence of obesity has been increasing.However, all previous data on obesity prevalence in Egypt [6][7][8][9][10][11][12][13][14][15][16][17][18] included relatively small sample sizes (the 2017 WHO's STEPwise approach to surveillance of non-communicable diseases (STEPS) survey included 6670 persons [15], the 2014 Demographic and Health Survey (DHS) included 19,021 adult females [17] and the 2015 Health Issues Survey included body mass index (BMI) data for 15,602 adult males and females [16]).In the last quarter of 2018, Egypt embarked on the largest population disease screening campaign in history, aiming at identifying and treating patients infected with the hepatitis C virus (HCV).Over 7 months in 2018 and 2019, 49.6 million persons were screened for HCV antibodies [19].During the same screening, persons also had their height and weight checked and body mass index (BMI) calculated.They also had their blood glucose and blood pressure measured.
Here we present the details of the BMI calculation for 49,630,319 Egyptian adults and compare it to the BMI data of 335,504 patients with HCV infection.

Methods
The details of the national health and HCV screening campaign in Egypt have been described previously [19,20].In brief, goals were set to screen the entire population 18 years of age or older (a target population of 62.5 million) for hepatitis C and to provide treatment to all those with HCV viremia, with the screening and treatment paid for by the state.In addition, all persons participating in screening had their height and weight recorded to calculate their body mass index (BMI) as part of screening for some noncommunicable diseases (NCDs).They also had their blood glucose and blood pressure checked.Results of HCV serostatus, BMI, blood glucose level, and blood pressure were recorded on a paper card given to the person for her/his records and entered electronically into a central database via computers or handheld devices via cellular networks.
Participation in screening was voluntary.Persons seropositive for HCV were referred for evaluation and treatment as described previously [19].Persons with elevated blood glucose or blood pressure were referred to the closest general hospital for evaluation and management, and persons with a BMI over 30 kg/m 2 were counseled about lifestyle modification and the need to lose weight.
Detailed population data for 2019 for the analysis of the screening data were obtained from the Central Agency for Public Mobilization and Statistics (CAPMAS) (the National Statistical Agency of Egypt), and the 2022 population to calculate current prevalence was obtained from CAPMAS report of October 2022 [21].
Overweight/obese is defined as a BMI of 25 kg/m 2 and above.Obesity is defined as a BMI of 30 kg/m 2 and above.A BMI of 30 kg/m 2 to less than 35 kg/m 2 is defined as class I obesity, a BMI between 35 kg/m 2 and 40 kg/m 2 as class II obesity, and a BMI of 40 kg/m 2 and higher as class III (morbid) obesity.A BMI of 25 kg/m 2 and less is defined as normal or underweight [22].
BMI data for patients with HCV viremia were obtained from the National Committee for Control of Viral Hepatitis (NCCVH) database at baseline before therapy with direct antiviral agents and compared to the general population by gender and age group.
Blood pressure was measured once in the sitting position using mercurial sphygmomanometers.Elevated blood pressure was considered if the blood pressure was ≥ 140 mmHg systolic and/or ≥ 90 mmHg diastolic.Blood glucose was measured using a capillary blood drop obtained through the same finger-prick used to test for the HCV antibody, using Accu-Check meters and strips from Roche Diabetes Care, Inc., Indianapolis, IN, USA.Persons were not required to be fasting or questioned about their fasting status, and all persons were presumed not to be fasting.Elevated blood glucose was considered if the blood glucose was 200 mg/dl or higher.

Statistical analysis
The following were calculated for country, state, and district levels: the percentage of persons in the target population who participated in screening and the prevalence of different weight categories among all screened persons categorized by gender and age group.Obesity prevalence was compared by gender and age group and compared to patients with hepatitis C infection.Results in each state and district were compared and analyzed according to sex, age group, and urban versus rural residence.
To assess the global ranking of obesity in Egypt compared to other countries, the age-standardized prevalence of obesity was calculated [24].Prevalence was compared to other countries' latest published age-standardized data obtained from the literature, and if no morerecent data was available, the WHO data for 2016 was used., [23,[25][26][27][28].
State obesity prevalence was correlated to state HCV prevalence obtained from the screening data [19] S2).
Applying the same prevalence rates to the 2022 population, the current number of persons with obesity in Egypt would be 26,599,410 (10,285,741 males and 16,313,669 females), and the number of overweight persons 23,457,410 (13,424,059 males and 10,033,351 females) (Supplementary Table S1).Thus 73.85% of the adult population is estimated to be currently overweight or affected by obesity.
Table 3 and Fig. 1 show the geographic distribution of obesity in males and females.In all states, obesity prevalence was significantly higher in females.The prevalence of obesity and female obesity was highest in the Nile Delta states (female obesity prevalence in Dakahlia was 62.4% (95% CI 62. 34-62.48)and in Gharbia 62.2% (95% CI 62.08-62.24), and more than 80% of adults in these two states are overweight or affected by obesity) and was lowest in the states in the south of the Nile valley with male obesity lowest in Qena (19.82% (95% CI 19.73-19.91))(Figs. 1 and 2, Supplementary Figures 3-5).In no state was overall obesity prevalence   S6).
Overall and in all states, obesity was higher in urban than in rural areas (Supplementary Table S2).Supplementary Tables S3-S11 show the age-related prevalence of weight categories in all states.

HCV
Weight data were obtained from the NCCVH database for 355,504 patients with HCV viremia at baseline before  S13, Figure S8) and increased with age till age 60 (Table S14, Figure S9).The prevalence of obesity was significantly lower in HCV patients than in the screened population (difference 3.54% (95% CI 3.24-3.64%)and 2.39% (95% CI 2.15-2.63%) in males and females respectively) (Supplementary Table S15, Supplementary Figure S9), and in all age groups (Supplementary Table S16).

Global ranking
Other than the 10 Pacific Island countries, Kuwait is the country with the highest prevalence of obesity followed by Qatar and the USA.Egypt ranks 4th country globally in overall obesity and ranks 1st in female obesity (Supplementary Table S17).

Elevated blood pressure and blood glucose
Five thousand three hundred forty-four persons (0.01%) had missing blood pressure and blood glucose data, and the analysis includes data for 49,624,975 persons.The prevalence of elevated blood pressure (> 140 mmHg systolic and/or 90 mmHg diastolic) was 21.03% (95% CI 21.02-21.05),was more common in males nationally and in all states, increased with age and was higher in urban than rural areas (Supplementary Table S18).The prevalence of elevated blood glucose (> 200 mg/dl) was 5.19% (95% CI 5.18-5.19), increased with age, was higher in females, and was higher in urban than rural areas (Supplementary Table S18).

Discussion
Globally, people are at higher risk of dying prematurely from NCDs.This risk is highest in low-and middleincome countries where the capacity to identify and treat NCDs might not be adequate.In Egypt, 84% of annual mortalities are attributed to NCDs [30].We show that, similar to the increasing global prevalence of obesity [1,31,32], the overall prevalence of obesity in Egypt has increased.Obesity prevalence had doubled from 12% in 1975 to 24% in 2003 [33], and the results presented here show that the prevalence has more than tripled to a prevalence rate of 39.84% (95% CI 39.82-39.85)by 2019 (Fig. 4).With the current data, Egypt has become the country with the highest prevalence of female obesity in the region and globally after the scarcely populated Pacific Island Nations [32][33][34][35].Ward et al. [36] classified obesity into moderate (BMI ≥ 30-< 35 kg/m 2 ) and severe (BMI ≥ 35 Kg/m 2 ) in their study on the future of obesity in the USA; a classification that is also used by the US National Center for Health Statistics (NCHS) in its reports on obesity in the USA [25].In this analysis, however, we used the WHO's  Similar to most countries in the Mediterranean and Middle East region [28], and unlike most countries in Europe [37] and recent data from the USA [25], the prevalence of obesity in Egypt is higher in females than in males.
Obesity as a global health problem has been recognized and addressed by several international policy strategies and plans.The World Health Assembly in 2004 [38] and the 2011 United Nations General Assembly's High-Level Political Declaration on the Prevention and Control of Non-communicable Diseases (NCDs) ( [39] resulted in the introduction of the "WHO Global Strategy on Diet,   Physical Activity and Health" that describes actions to support healthy diets and regular physical activity [40]. In addition, the "Global Action Plan on Physical Activity 2018-2030: More Active People for a Healthier World" provides policy actions to increase physical activity globally as measures to address the global rise in the prevalence of obesity.The targets for alleviating the impact of NCDs agreed upon by member states of the World Health Organization in 2013 [41] include a 25% reduction of premature deaths from non-communicable diseases by 2025, and halting the increase in the rise of obesity by the year 2025 to the prevalence level of 2010 [40], a target that is unachievable in Egypt.The overall prevalence of obesity in Egypt in 2010 was 27.2% (95% CI 23.9-29.8%), of male obesity was 18.4% (95% CI 14-23.3%)and of female obesity 35.9% (95% CI 30.8-41.2%).Although the rate of increase of the prevalence of obesity has been decreasing slightly in Egypt over the last three decades, the 2019 prevalence data (60% increase in male obesity and 38% increase in female obesity over the 2010 levels) indicate that the WHO's target of a prevalence in 2025 equal to the 2010 levels cannot be achieved.Although the rate of increase of obesity appears leveling off or stagnating in several high-income countries [42][43][44][45], this does not appear to be happening any time soon in Egypt, and unless major changes take place, the increasing trend will continue.
What makes the problem more crucial is the high prevalence of obesity in young adults.Between age 18 and 25, 34% are overweight and 18% are affected by obesity, with 58% in Gharbia in the Nile Delta either overweight or affected by obesity.Among all those younger than 35, 64% are either overweight or affected by obesity, a prevalence that reaches 78% in the several Nile Delta states.In addition, of 17,045,798 women of child-bearing age Halting the increase in obesity requires the national adoption of comprehensive social, educational, and food policies to change the population's eating habits and promote physical activity.In acknowledgement of the problem, the Egyptian government and the MoH have started to undertake several steps to confront the high prevalence and increasing trend of obesity.A sin-tax is being prepared for beverages with sugar levels exceeding 5 mg/100 ml.Annual follow-up of schoolchildren in school clinics and MoH primary healthcare facilities includes anthropometric measures, and since 2019, all schoolchildren between 6 and 12 years have annually screened for obesity, anemia, and stunting.For adults, efforts to advertise and promote exercise and physical activity have started, and the number of nutrition clinics supervised by the National Nutrition Institute and bariatric surgery centers in government hospitals has been scaled up.However, with the current prevalence in this report, a comprehensive national plan should be employed to address this important problem and to halt and reverse the rising trend.The results in this report highlight the hottest spots of obesity which require intensive interventions on behalf of the MoH and policy makers.
These data show that, excluding the Pacific Island countries, Egypt has become the fourth country globally in overall obesity and ranks first in female obesity, with an age-standardized prevalence of obesity of more than 50% in adult females.Published data for other countries, however, are based on rather old screening studies (the latest available data and published reports for Qatar are based on the 2012 STEPS and for Kuwait on the 2014 STEPS reports).This ranking might change when more recent data become available from other countries.
The high prevalence of overweight and obesity is undoubtedly having and will continue to have a large impact on health in Egypt.It is probably a major factor in the 17.2% (95% CI 9.2-19.6)prevalence of T2DM [47], and the 29.2% (95% CI 27.5-31.0)prevalence of hypertension reported in the 2017 STEPS survey [15] among Egyptian adults.This high prevalence of obesity is probably also contributing to the incidence of cardiovascular, cerebrovascular, and musculoskeletal diseases, cognitive decline, many types of cancer, and overall mortality [1].The economic impact, both in direct and indirect cost, has not been calculated and is expected to be massive.
The reason for the high prevalence of overweight and obesity in Egypt is probably multifactorial.The type of diet with high content of wheat and carbohydrates is a contributing factor, where the per-capita consumption of wheat and sugar in Egypt are among the highest in the world with national per-capita wheat consumption three times the global per-capita average and sugar consumption double the global per-capita average [48].Over the past three decades, Egypt has witnessed increasing personal income, which probably impacted the increase in the prevalence of obesity as evidenced by the inverse correlation of state obesity prevalence and state poverty level.In addition, Egypt has seen an increase in urbanization and a sedentary lifestyle, which is coupled with a lack of exercise and physical activity, and cultural factors limiting female exercise.These factors contribute to the impact of diet habits in increasing the prevalence of overweight and obesity.
Prevalence of obesity in patients with hepatitis C viremia was lower than in the screened population, but similar to the screened population, increased with age till age 60, and was higher in females than in males in all age groups.In all age groups and in males and females, patients with HCV were less affected by obesity than the screened general population.The reason for the lower prevalence of obesity in HCV patients is not directly known, and the severity of liver disease in these patients was not evaluated.
The strength of this study is the huge sample size which is the largest screening campaign and BMI evaluation in history.
However, the study also had several limitations.Although the European Association for the Study of the Liver (EASL), the European Association for the Study of Diabetes (EASD), and the European Association for the Study of Obesity (EASO), in joint clinical practice guidelines, recommended screening for non-alcoholic fatty liver disease (NAFLD) in people with obesity [49], yet the persons with obesity in this program were not screened for NAFLD by laboratory tests or ultrasound, and we cannot comment on the prevalence of NAFLD from our results.
The only anthropometric measure calculated in this screening program was the BMI.Several reports suggest that waist-circumference, waist-hip ratio, and waistheight ratio are better measures to predict the risk of development of cardiovascular disease or diabetes in relation to obesity [50][51][52].We did not record waist circumference, and none of these measures were registered in the current screening.
No questionnaires or data were collected regarding dietary and exercise habits, personal and household income, or social parameters.The huge number of screened population and large daily flow (the average daily flow was 230,000 persons, and as many as 550,000 persons were screened in one day when the screening campaign was ongoing in Cairo) did not allow for collecting these data.
Although obesity is a known risk factor for the development of T2DM and hypertension, its role in the screened population cannot be determined from the current data.The screening program identified 2.57 million persons (5.19% (95% CI 5. 18-5.19) of the screened population) with blood glucose ≥ 200 mg/dl.However, these do not represent the prevalence of diabetes in Egypt.The number of patients with diabetes and blood glucose < 200 mg/dl on medication for raised blood glucose among the screened population is not known, the fasting state of the screened population was not recorded, and the prevalence of diabetes in the population and its correlation to weight categories cannot be determined.In the WHO's 2017 Egypt STEPS survey, the total prevalence of elevated blood glucose or treatment for diabetes was 15.5 [15], and the International Diabetes Federation (IDF) estimated the prevalence of T2DM in adults in Egypt in 2017 at 15.1% [95% CI 8.1-17.2][47].Similarly, although the prevalence of elevated blood pressure in the screened population was 21.03% (95% CI 21.02-21.05%),this does not represent the prevalence of hypertension in the screened population, and the number of persons on antihypertensive medication is not known.In the WHO's 2017 Egypt STEPS survey that included data for 6680 adults, the percentage of persons with elevated blood pressure or on anti-hypertensive medication was 29.5% (95% CI 28.0-31.0%)[15].
In conclusion, this is the largest national screening program for overweight and obesity, where we have highlighted that obesity is a major health problem in Egypt and that its prevalence is still increasing, and is currently among the highest in the world.Addressing the problem requires the national adoption of comprehensive social, educational, and food policies and the promotion of physical activity.We have highlighted that the obesity problem starts in young adults and identified the high prevalence areas at the district level.

Fig. 1
Fig. 1 District-level prevalence of obesity (BMI ≥ 30 kg/m 2 ) in males and females.The enlarged area of the country maps includes the Urban, Nile Delta, and Nile Valley States (98.3% of the population)

Fig. 2
Fig. 2 Bubble chart for the state prevalence of obesity (BMI ≥ 30 kg/m 2 ) and number of persons with obesity in the screening program.The size of the bubble represents the number of persons with obesity in the state, and the y-axis is the prevalence of obesity (%) in the state.The states are arranged by the number of persons with obesity on the x-axis, with the largest number of persons with obesity to the far left, and the least numbers to the far right

Fig. 3
Fig.3Correlation between state prevalence of obesity (BMI ≥ 30 kg/m 2 ) and state prevalence of poverty (% of state population poor)

Table 1
Weight categories among Egyptian males and females

Table 2
Prevalence of obesity (BMI ≥ 30 kg/m 2 ) among Egyptian males and females by age group

Table 4
Weight categories in male and female patients with HCV

Table 5
Weight categories in different age groups in patients with HCV

Table 6
Weight categories in males and females in patients with HCV and screened population

Table 7
[46]ht categories in different age groups in patients with HCV and screened population Trend of the prevalence of obesity (BMI≥ 30 kg/m 2 ) with confidence intervals (A) and of mean BMI (B) in males and females since 1992 screened, 43.60%, (95% CI 43.57-43.62%)wereaffectedby obesity.This increases the possibility of obesity in their children, as the risk of childhood and future obesity increases by more than 250% with maternal obesity[46].Overweight/obesity that starts at a young age indicates that interventions and efforts to address the problem must start early in life and must include interventions to reduce obesity in all women of reproductive age.