Determinants of undernutrition among khat chewing and non-khat chewing male adults in Addis Ababa, Ethiopia: a comparative cross-sectional study

Khat chewing is a deep-rooted socio-cultural tradition that affects appetite, gastric emptying, and food intake, ultimately influencing nutritional status. Moreover, there is significant variation in lifestyles and ways of living among khat chewing and non-chewing people. However, there is limited evidence on the disaggregated determinants of undernutrition among khat chewers and non-chewers in Ethiopia. A community-based comparative cross-sectional study was conducted with 253 Khat-chewing and 249 non-chewing male adults in Addis Ababa, Ethiopia. Weight and height were measured under standard procedure and used to calculate the body mass index (BMI < 18.5 kg/m2 indicates undernutrition). Variables with p-values below 0.25 in the bi-variable analysis were entered into a multivariable logistic regression model to identify factors associated with undernutrition and to control confounding respectively. An adjusted odds ratio with 95% confidence interval was used to declare the presence and the strength of association between the independent and outcome variable. Statistical significance was declared at a p value of 0.05. In this study, a total of 138 (27.5%: 23.6–31.6%) adult males were undernourished; among them, 78 (32.0%) were khat chewers and 60 (23.9%) were non chewers. Christian religion (AOR = 1.49; 1.02–2.30), vegetable consumption (AOR = 1.69; 95% CI 1.12–2.55) and khat chewing (AOR = 1.60; 1.04–2.45) were independent risk factors for undernutrition. However, none of the above factors showed a statistically significant association among non-khat chewer male adults. In conclusion, undernutrition was a public health concern in male adults in the study area. Frequent consumption of fruits, vegetables and family size of the households were the independent predictors of undernutrition. The practical implication of identifying risk factors of undernutrition among chewers and non-chewers could be helpful in depicting the relevant risk factors by exposure category and helping to further refine intervention packages. In addition, focusing on interventions which can increase the availability and accessibility of fruits and vegetables are important to improve the nutritional status of adult male populations.


Sample size determination
The sample size was calculated using Epi Info version 7 for the sample size module using the following assumptions: 39.0% and 22.4% prevalence of undernutrition among khat chewers and non-khat chewers from previous similar study, respectively 16 , with 95% certainty, 5% significance level, 80% power of detection, 10% non-response rate, the proportion of khat chewers to non-chewers being 1:1 and considering a design effect of 2, the final calculated sample size for this study was 506.

Sampling technique
Addis Ababa city is comprised of 11 sub-cities.However, for this study, one randomly selected sub-city was targeted, which could be very representative of the whole city.The selected sub-city (kolfe-keraniyo) in turn consists of 11 smaller administrative levels (kebeles).Using the same sampling technique (SRS), four kebeles were selected, and all khat chewing shops in the selected kebeles were listed.Using the list, we identified 253 khat-chewers from the chewing shops and 249 non-chewers of similar groups engaged in different activities around the shop.In the meantime, stratified random sampling with proportional allocation was employed to select the number of adults for each kebele and study group.

Data collection procedures
A structured, pretested questionnaire was used for the face-to-face interview.The questionnaire was prepared after reviewing different literatures [2][3][4]7,9,20,33 . Anthropomtric data was collected using standard procedures 35 .Relevant socio-demographic and other data were captured in a standardized manner in local languages.Weight was measured using a portable battery-operated Seca digital scale (Seca, Germany).The weighing scale was adjusted to zero before the adult was asked to stand on it. Inaddition, the proper functioning of each scale was checked every day by a known 3-kg sand-filled plastic bottle before the fieldwork.During the procedure, the subjects were dressed in light clothes and took off their shoes.The weight was recorded to the nearest 0.1 kg.Height was measured using a portable stadiometer.All participants have been measured against the wall in an upright position, without foot wear, with heels together, their heads positioned in such a way that the posterior part (the occipital prominence) touches the vertical measuring board, and their eyes looking straight ahead (Frankfurt plane), so that the line of sight is perpendicular to the body.The knees are straight, arms at sides, and the heels, buttocks, and shoulder blades touch the vertical surface of the stadiometer.The height was recorded to the nearest 0.1 cm.Both weight and height measurements were taken in duplicate and the average of the two measurements was considered for the final analysis.
The operational definitions given to the most important variables were: 'Underweight' , defined as a condition when the BMI (body mass index) is below 18.5 kg/m 2 , obtained by dividing the weight of an individual in kilograms, to the square of height in meters.It is classified as: 'underweight' if BMI < 18.5 kg/m 2 , 'normal' if BMI ≥ 18.5 to 24.9 kg/m 2 , 'overweight' if BMI ≥ 25.0 to 29.9 kg/m 2 and obesity if the BMI is 30.0 kg/m 2 or higher 34 .'Dietary patterns' , was defined as quantities, proportions, variety, or combination of different foods, drinks, and nutrients in diets and the frequency with which they are habitually consumed in each meal.In this study, a dietary pattern was considered as 'poor' if an individual consumed two or less meal per day and 'good' if three or more meals were consumed per day 36 .'Vegetable and fruit consumptions' , implying a coded responses to vegetable and fruit related questions in the form of servings/week and the level of participant's consumption of fruits and vegetables.Accordingly, the individual was labeled as 'less frequent consumer' if he used six or less servings per week and frequent if he consumed seven or more servings per week.Khat chewer: An individual who chewed khat at least once in the last month before the study and currently actively engaged in khat buying and chewing 37 .

Data quality control
The questionnaire was prepared in English and then translated into the local language (Amharic).Before using the Amharic version for data collection, a re-translation back to English was made by language experts to check for consistency.Five percent of the sample was pretested in a non-selected sub-city (Gulele) to ensure that respondents were able to understand the questions and to check the wording, logic, and skip order of the questions in a sensible way.A slight modification of the questionnaire was made based on pre-test findings.Two days of demonstration-based training were given for data collectors.Measuring devices were kept at a standard level.Validation and calibration of the instrument after each measurement and after moving the instrument from one place to another were performed.Data collectors were recruited based on their qualifications, fluency in local language for effective communication and prior experience in data collection.All the procedures were checked for consistency and accuracy during supervision periods.www.nature.com/scientificreports/

Data processing and analysis
After data collection, each questionnaire was checked manually for completeness, missed values, and unlikely responses, then coded, and entered using Epi-data version 3.1 for data exploration and cleaning.The cleaned data was exported to SPSS version 23.0 for statistical analysis.Descriptive statistics were computed to determine frequencies and summary statistics (mean, standard deviation, and percentage) to describe the study population.Data were presented using tables, graphs, and figures.Bi-variable logistic regression analysis was used to show the association between dependent and predictor variables.Variables that were found to be statistically significant at p-value < 0.25 during bi-variable analysis were considered for further analysis in multivariable logistic regression model.Adjusted odds ratios with their 95% CI was computed and variables having p-value less than or equal to 0.05 in the multivariable logistic regression model were considered statistically significant and independent predictors of the outcome variable.Hosmer-Lemeshow's goodness-of-fit statistics 38,39 were conducted to determine whether the model adequately describes the data (p-value of 0.53 indicating a fit model).

Ethical approval
The ethical approval was obtained from the Institutional Review Board of Wolkite University, College of Medicine and Health Sciences.Then, the detailed purpose of the study was explained to all study participants, and written informed consent was obtained from each participant.All information collected from the respondents was kept confidential by the investigator.The participants had the right to withdraw from participation whenever they wanted to.A work permission letter was obtained from the office of the local health bureau and all methods and procedures were conducted in accordance with the approved ethical standard and, with respect to studies involving human subjects, in accordance with the Helsinki Declaration.

Socio-demographic characteristics
A total of 502 individuals participated in this study (253 khat chewers and 249 non-chewers).Among the nonkhat chewer participants, four individuals refused to answer the questions, giving a response rate of 99.2%.The mean age ± Standard deviation of participants was 37.5 ± 11.29 years.The leading khat chewers were in the age group 15-24 years, constituting 269 (67.8%), followed by the age group 25-64 years, constituting 108 (27.2%).These two, together comprising a total of 95.0% of khat chewers, were in the active and productive age groups.More than half of khat chewers, 226 (56.9%) and 241 (60.7%) were married and college graduates, respectively).About two-thirds of the respondent's average monthly income lies between 2500 and 5000 Ethiopian birr per month for both groups (US$43-92).Regarding family size, half of the respondents in the khat-chewer group had small families size (1-3).In addition, there was no statistically significant difference in the baseline characteristics of study participants among khat chewers and non-khat chewers (Table 1).

Factors associated with undernutrition
In the regression analysis model, we employed three separate models.While the first was to explore the determinants of undernutrition (khat chewing included) among the general population, the latter two involve separate models among khat chewers and non-chewers.We explored the factors associated with undernutrition after checking for model fitness using Hosmer and Lemeshow's test (p = 0.622).First, bi-variable logistic regression analysis was conducted and all variables with a p-value ≤ 0.25 in the bi-variable analysis were fitted into the multivariable logistic regression analysis.Accordingly, religion, vegetable consumption per week, and khat chewing were found to be significant predictors of undernutrition at p-values ≤ 0.05.Being Christian in religion (AOR = 1.49; 95% CI 1.02-2.30)and having frequent vegetable intakes per week (AOR = 1.69; 95% CI 1.12-2.55)were associated with 1.49 times and 1.69 times increased risk of undernutrition, respectively.More importantly, khat chewing was significantly associated with a 60% increased risk of being undernourished (AOR = 1.60; 95% CI 1.04-2.45).This indicated that khat chewing is an important determining factor for undernutrition among adult males (Table 3).

Factors associated with undernutrition among khat chewers and non-chewers (comparison)
As presented above, khat chewing was a main determinant factor for undernutrition in this study (Table 3).In this section, we tried to compare factors other than khat chewing in relation to undernutrition in khat chewers and their non-chewer counterparts.

Discussion
The findings from this study revealed that the overall prevalence of undernutrition among adult males was 27.5%.This finding was in line with the studies conducted in Gulalle sub-city, Addis Ababa 29 , Chiro district, eastern Ethiopia 16 , and Jimma town, southwest Ethiopia 5 .The similarity of the findings could be due to the similarity in the study area and participant population.When disaggregated by khat chewing status, the prevalence of undernutrition was higher among khat chewers (32.0%) than their non-chewer counterparts (23.9%), but such difference was not statistically significant in current study.Similar findings were reported by different researches conducted in Brazil, Taiwan, and among slum dwellers in Guwahati.As revealed by all of these researches, chewing khat was not significantly associated with BMI 9,13,15 which was in agreement with our study findings.Khat chewers are usually prone to concurrent consumption of large volumes of sugary drinks and sweets to counteract the bitter taste of khat.Most ultra-processed foods and sugar-sweetened beverages are categorized as unhealthy foods.Frequent consumption of these foods has been associated with undernutrition and vitamin deficiencies by providing excess calories while lacking important micronutrients.This coupled with reduced appetite and poor nutrition further exacerbates the nutritional disturbances 29 .
Concerning factors associated with undernutrition, the vegetable and fruit intake of khat chewer adults was found to be associated with undernutrition.Those adults whose vegetable and fruit intake were below the optimum were more likely to be undernourished as compared to those who were taking optimum fruits and vegetables.This was comparable with the studies conducted in Addis Ababa and eastern Ethiopia 16,29 .The reason behind this might be that adults with low intakes of vegetables and fruit may not get adequate nutrients in their diets that meet the increased nutrient requirements, which in turn results in undernutrition due to depletion.
In the current study, we found that the odds of undernutrition were higher among Christian khat chewers (AOR = 1.90; 95% CI 1.04-3.44)as compared to their Muslim counterparts.Contrary to our finding, previous studies reported a higher prevalence of undernutrition among Muslim khat chewers [20][21][22] compared to Orthodox Christians.Another national study estimated that 23.6% of adults consume khat, and the odds of khat chewing increased by 18-fold among Muslim followers 19 .Hence, these might indicate the role of extraneous factors like season (since this study was conducted from February to March which is fasting time for Easter in orthodox Christians), limiting actual food intakes, and repeated fasting and animal-source food restrictions.In addition, the smaller number of Christian khat chewers might be more addicted, with limited adaptation affecting their actual food intakes 28 and predispose them to undernutrition 14 .
Another factor that partly determines undernutrition among khat chewers is family size.Adult khat chewers who had extended family (≥ 4 members) were more likely to become undernourished as compared to those who had fewer family numbers (1-3).A comparable study from Nekemte, Ethiopia, revealed that participants who had a larger family were five times more likely to be underweight 11 .Another study conducted in Arba Minch Zuria district, southern Ethiopia, showed similar findings.According to the study, lactating mothers who had a family size of 4-6 members were 2.3 times more likely to be undernourished compared to those who had a family size of 1-3 members 12 .
The findings of this study have wide practical implications.Reducing the khat chewing habit in adults could have an important effect on their health and, in turn, on the economic development of the nation.It is important to have such information on khat chewing practices to identify predisposing factors associated with it and draw due attention to alleviate the negative impacts of khat chewing on the individual, family, and society as a whole.Finally, the study was not free of limitations.In this study, generalization of the findings was limited as all the participants were adult males recruited from an urban setting.Another limitation could be under-reporting, as www.nature.com/scientificreports/some of the respondents might hide their actual feeding practices or khat-chewing habits.Since the data collection was based on self-report, it may be subjected to recall bias.However, due attention was given to the entire procedure, and since the respondents were probed, its effect might not be a threat to the findings of the study.

Conclusion
Overall, we tried to quantify the burden of undernutrition and modifiable risk factors for the development of undernutrition among two comparative groups (khat chewers and non-chewers).Hence, undernutrition was a public health concern among male adults in the study area.Khat chewing was found to be a significant predictor of undernutrition in addition to dietary consumption of fruits, vegetables and family size of the households.Moreover, identifying risk factors of undernutrition among chewers and non-chewers could be helpful in depicting the relevant risk factors by exposure category and helping to further refine intervention packages.Based on the finding, the following recommendations can be drawn for government, health professionals and future researchers.Government should give due emphasis on the harmful effects of khat chewing beyond its potential source of export income.Health professionals working at community and health facility level should counsel adult khat chewers about the negative effect of khat on health and to reduce the habit of chewing khat.We also suggest future researchers in the same topic to consider feminine gender in rural community, since this study addressed only male adult with urban setting. https://doi.org/10.1038/s41598-024-54471-5

Table 2 .
Diet-related factors and substance use between khat chewer and non-chewer in Addis Ababa, Ethiopia, 2022.

Category Khat chewers Non-chewers P-value Number (%) Number (%)
Prevalence of undernutrition by the khat chewing status of adult male in Addis Ababa, Ethiopia, 2022.

Table 3 .
Bi-variable and multivariable logistic regression output for factors associated with undernutrition among adult males in Addis Ababa, Ethiopia, 2022.¶ No significant association at P < 0.05.*Significant association at P < 0.05.