Prevalence and correlates of multiple non-communicable diseases risk factors among adults in Sudan: Results of the first national STEPS survey in 2016


 Background

Non-communicable diseases (NCDs) are on the rise in low- and middle-income countries. The aim of this study was to assess the prevalence and correlates of multiple NCD risk factors among adults in Sudan.
Methods

Cross-sectional nationally representative data were analysed from 7,722 18–69 year-old individuals (median age = 36 years) that took part in the “2016 Sudan STEPS survey.”
Results

The prevalence of individual NCD risk factors was 94.6% inadequate fruit and vegetable intake, followed by hypertension (31.6%), general overweight/obesity (28.0%), low physical activity (21.3%), current tobacco use (15.7%), raised total cholesterol (13.6%), diabetes (5.9%), and heavy episodic drinking (1.7%). In all, 34.2% had 0–1 NCD risk factor, 33.5% 2 risk factors, and 32.4% 3 or more NCD risk factors. In adjusted ordinal logistic regression analysis, compared to individuals 18–34 years old, persons 50–69 years old were 3.52 times (AOR: 3.52, 95% CI: 2.88–4.31) more likely to have multiple NCD risk factors. Men were 21% (AOR: 1.21, 95% CI: 1.00-1.46) more likely than women to have multiple NCD risk factors. Individuals residing in urban areas were 86% (AOR: 1.86, 95% CI: 1.49–2.32) more likely than individuals residing in rural areas to have multiple NCD risk factors, and compared to persons never married, married participants and persons separated, divorced or widowed persons were 51% (AOR: 1.51, 95% CI: 1.22–1.87) and 74% (AOR: 1.74, 95% CI: 1.22–2.47), respectively, more likely to have multiple NCD risk factors. Compared to persons with less than 500 pounds household income, persons with over 2000 pounds household income were 75% (AOR: 1.75, 95% CI: 1.28–2.38) more likely to have multiple NCD risk factors. Compared to women who cannot read or write, women who had more than primary education were 38% (AOR: 1.38, 95% CI: 1.06–1.80) more likely to have multiple NCD risk factors. Compared to men who were self-employed, engaged in non-paid work, were students or unemployed (able to work), government employees, non-government employees, retired or unemployed (unable to work) had a significantly higher odds of having multiple NCD risk factors.
Conclusion

Almost one in three participants had three or more NCD risk factors and several associated variables were identified that can facilitate in designing intervention programmes.

Non-communicable diseases (NCDs) are "estimated to account for 52% of all deaths in Sudan in 2016" [1]. More than 85% of NCD "premature" deaths occur in low-and middle-income countries [2]. Cardiovascular diseases, cancers, respiratory diseases, and diabetes contribute to over 80% of all premature NCD deaths [2]. Poor diets, tobacco use, harmful alcohol use, and low physical activity all increase the risk of dying from a NCD [2]. In the rapid increase of NCDs in sub-Saharan Africa and the Eastern Mediterranean region, it is "crucial to have a careful understanding of the local drivers of NCDs" [3,4]. There is lack of national data on the prevalence of multiple NCD risk factors and associated factors among adults in community-based surveys in Sudan, a low-income country geographically in sub-Saharan Africa. Some population-based studies among adults in Sudan were sub-national and only focused on speci c NCD risk factors, such as the prevalence of overweight/obesity was 56.1% in four states (Khartoum, Gezira, Blue Nile, and Kassala) [5], 59.0% in Gadarif, Eastern Sudan [6], hypertension was 16.6% in four states (Khartoum, Gezira, Blue Nile, and Kassala) [7], 40.8% in Gadarif, Eastern Sudan [8], the 35.7% in four main cities of the River Nile State, north Sudan [9], 23.6% in the [2005][2006] Khartoum State STEPS survey [10], and 27.6% in Khartoum State in Sudan [11]. The prevalence of diabetes was 19.1% in four main cities of the River Nile State, north Sudan [12], 18.7% in the Northern State and River Nile State [13], and 19.8% in the 2005-2006 Khartoum State STEPS survey [10]. In a community-based study in Khartoum state, Sudan, the prevalence of physical inactivity was 53.8% [14], the prevalence of current smoking was 12.0% in the 2005-2006 Khartoum State STEPS survey [10], and in a cross-sectional survey of 403 households in Kassala State, Sudan, 72.8% and 36.2% rarely or did not consume fruit and vegetables, respectively [15].

Measures
Outcome variables: NCD risk factors Behavioural NCD risk behaviour variables included inadequate fruit and vegetable intake (<5 servings/day), low physical activity based on the "Global Physical Activity Questionnaire", current tobacco use (smoking and/or smokeless tobacco), and episodic heavy alcohol use (six or more in one session) in the past months [23].
Biological NCD risk factors. Fasting (≥10 hours) blood sugar measurements were conducted and diabetes was de ned as "fasting plasma glucose levels ≥7.0 mmol/L, and/or currently taking insulin or oral hypoglycemic drugs." [23] Hypertension was assessed based on measured blood pressure (BP) (mean of the last two of three readings) de ned as systolic BP ≥140 mm Hg and/or diastolic BP ≥90 mm Hg or currently on antihypertensive medication; raised total cholesterol (TC) ("fasting TC ≥5.0 mmol/L or currently on medication for raised cholesterol"); Body Mass Index (measured 25-29.9kg/m 2 overweight and ≥30 kg/m 2 obesity) [23].
Exposure variables included, sex, age, work status, education, household income, residence status and marital status [23].

Data analysis
Statistical analyses were conducted with "STATA software version 15.0 (Stata Corporation, College Station, Texas, USA)," considering the complex study design. All results were weighted by age and sex categories." [23] The number of NCD risk factors (10) were classi ed into three groups, 1=0-1, 2=2 and 3=3-8 NCD risk factors, and described with frequency counts and bar graphs. Unadjusted and adjusted ordered logistic regression were used to assess predictors of one or more NCD risk factors. Missing values were not included in the analysis. P<0.05 was accepted as signi cant.

Sample and NCD risk factor characteristics
The sample included 7,722 adults (35.1% males and 64.9% females) aged 18 to 69 years, median age 31 years (IQR: 23-43). About one-third of the participants (34.0%) could not read and write, 51.7% had an household income of 1000 or less Sudanese pounds, and 62.9% were residing in rural areas.
The prevalence of individual NCD risk factors was 94.6% inadequate fruit and vegetable intake, followed by hypertension (31.6%), general overweight/obesity (28.0%), low physical activity (21.3%), current tobacco use (15.7%), raised total cholesterol (13.6%), diabetes (5.9%), and heavy episodic drinking (1.7%). The prevalence of tobacco use and heavy episodic drinking was signi cantly higher in men than in women, while low physical activity, general overweight/obesity, raised total cholesterol and diabetes was signi cantly higher in women than in men (Table 1).
Individuals residing in urban areas were 86% (AOR: 1.86, 95% CI: 1.49-2.32) more likely than individuals residing in rural areas to have multiple NCD risk factors, and compared to persons never married, married participants and persons separated, divorced or widowed persons were 51% (AOR: 1.51, 95% CI: 1.22-1.87) and 74% (AOR: 1.74, 95% CI: 1.22-2.47), respectively, more likely to have multiple NCD risk factors. Compared to persons with less than 500 pounds household income, persons with over 2000 pounds household income were 75% (AOR: 1.75, 95% CI: 1.28-2.38) more likely to have multiple NCD risk factors. Compared to women who cannot read or write, women who had more than primary education were 38% (AOR: 1.38, 95% CI: 1.06-1.80) more likely to have multiple NCD risk factors. Compared to men who were self-employed, engaged in non-paid work, were students or unemployed (able to work), government employees, non-government employees, retired or unemployed (unable to work) had a signi cantly higher odds of having multiple NCD risk factors (Table 3).

Discussion
The present study aimed to assess the prevalence and correlates of multiple NCD risk factors in a national community-based survey among 18-69 year-old individuals in Sudan.  [16]. The clustering of three of more NCD risk factors was common in this survey predisposing the adult population in Sudan to a greater risk of NCDs.
In agreement with some studies [16,[19][20][21][22], this study showed that older age, male sex, being married, urban residence, higher household income, being in salaried employment, and among women higher education increased the odds for multiple NCD risk factors. Regarding increasing age, early screening, in particular among males, those with higher income, higher education and residing in urban areas, should be propagated to prevent an accumulation of NCD risk factors in Sudan.
Regarding individual NCD risk factors, the four most prevalent were inadequate fruit and vegetable intake (94.6%), hypertension (31.6%), overweight/obesity (28.0%), and low physical activity (21.3%). Similar results were found in the Kenya [16] and Nepal [19] STEPS surveys. The prevalence of hypertension was higher than in previous three local surveys, in four states (Khartoum, Gezira, Blue Nile, and Kassala) (16.6%) [7], in the 2005-2006 Khartoum State SEPS survey (23.6%) [10], and in Khartoum State in Sudan (27.6%) [11], but lower than in two other local surveys in Gadarif, Eastern Sudan (40.8%) [8], and in four main cities of the River Nile State, north Sudan (35.7%) [9]. The prevalence of overweight/obesity (28.0%) was lower than in four states (Khartoum, Gezira, Blue Nile, and Kassala) (56.1%) [5], and in Gadarif, Eastern Sudan (59.0%) [6]. The high prevalence of inadequate fruit and vegetable intake (94.6%) in this survey was also found in a community in Kassala State, Sudan (72.8% and 36.2% rarely or did not consume fruit and vegetables, respectively) [15]. The 2016 Sudan STEPS survey team recommend to "strengthen health literacy and capacity of individuals to make healthy choices e.g. by making fruits and vegetable more affordable" [23].
The prevalence of current tobacco use (15.7%) and heavy episodic alcohol use (1.7%) in this study was in terms of tobacco use similar to the 2005-2006 Khartoum State STEPS survey (current smoking 12.0%) [10], the Kenya STEPS survey (smoking: 10.2%) [16] and the Malawi STEPS survey (tobacco smokers: 14.1%) [17] but lower in terms of heavy drinking in the Kenya STEPS survey (harmful alcohol use: 13.8%) [16] and the Malawi STEPS survey (excessive alcohol drinkers: 7.7%) [17]. Increasing exercise taxes and prices on tobacco products may be recommended in Sudan [24].
The prevalence of low physical activity (21.3%) in this survey was lower than in a study in Khartoum state, Sudan, (53.8%) [14]. The proportion of raised total cholesterol (13.6%), and diabetes (5.9%) in this study was lower than in the 2005-2006 Khartoum State STEPS survey (raised total cholesterol 19.8% and diabetes 19.8%) [10] in four main cities of the River Nile State, north Sudan (diabetes 19.1%) [12], in the Northern State and River Nile State (diabetes 18.7%) [13], but higher than in the Malawi STEPS survey (raised cholesterol: 8.7% and raised fasting blood glucose: 5.6%) [17] and the Kenya STEPS survey (high blood total cholesterol: 10.1% and diabetes: 2.6% [16]. Some of the found NCD risk factors differed by sex. Current tobacco use and heavy episodic drinking was signi cantly higher in men than in women, while low physical activity, general overweight/obesity, raised total cholesterol and diabetes was signi cantly higher in women than in men. In the Kenya STEPS survey daily tobacco and harmful alcohol use was also more prevalent in men than in women, obesity and raised total cholesterol was more common among women than men were [16]. Similarly, in the Malawi STEPS survey, the prevalence of alcohol use and tobacco smoking was higher in men than women, and overweight/obesity and raised cholesterol were higher in women than men were [17]. The higher prevalence of overweight/obesity in women may be attributed to "in Sudan, obesity is associated with beauty. Furthermore, some young women in Sudan use steroids to gain weight and refuse to take metformin because it is associated with weight loss." [25]. These gender differences in the prevalence of different individual NCD risk factors as well as multiple NCD risk factors need to be taking into account in NCD health promotion interventions [17].
This study was limited because of the self-report of the interview data as well as its cross-sectional design. Further, the public use dataset of the Sudan 2016 STEPS survey did not include some of the variables, such as region and state, which could therefore not be included in the analysis.

Conclusion
The study found among a nationally representative population of 18 to 69 years in Sudan that almost one in three participants had three or more NCD risk factors. Several associated factors were identi ed for multiple NCD risk factors, including older age, male sex, urban residence, higher household income and among women higher level of education, which can assist in guiding interventions to prevent multiple NCD risk factors in the Sudanese population. Considering the clustered nature of NCD risk factors, interventions are needed that target multiple, in particular modi able, NCD risk factors.

Availability of data and materials
The data on which this analysis were based are publicly available at the World Health Organization NCD