Knowledge attitude and behaviour towards dietary salt intake among Bangladeshi medical and nonmedical undergraduate students

Background: Noticeable proportion of Bangladeshi population is habituated with added salt use during meal, but there was no data among medical and nonmedical students. Objective: The objective of this study was to assess the knowledge, attitude and behavior about dietary salt among Bangladeshi medical and nonmedical undergraduate students. Methods: It was a cross-sectional study among 280 (140 medical; 140 nonmedical) undergraduate students. Medical students were from MBBS and physiotherapy background, whereas nonmedical students were from business, law, engineering and pharmacy background. A semi-structured questionnaire was developed using WHO Modified Salt Module of STEPS Questionnaire, and used for data collection. Data were analyzed in terms of both descriptive and comparative statistics. Results: Men dominated both groups (medical, 59.3% and nonmedical, 64.3%) and the mean age was 22.0±2.0 and 21.8±1.9 years in medical and nonmedical group respectively. Medical students possessed better knowledge and showed better positive attitude towards salt intake than the counterpart. There were significant differences between the groups regarding the perception on health effect of salt (p, 0.005) and importance of lowering salt (p, 0.040). Nonmedical students were significantly more habituated in practicing added salt (p, 0.001) than the counterpart. Conclusion: Medical students had better knowledge, attitude and less practicing habit towards dietary salt.


Introduction
High dietary salt (sodium chloride) consumption has been considered as an important risk factor for the development of noncommunicable diseases (NCD) especially cardiovascular diseases (World Health Organization, 2017a).It is wellestablished that high salt is intertwined with elevated blood pressure and hypertension leading to cardiovascular diseases, mainly heart attacks and stroke (Strazzullo et al., 2009 andKotchen et al., 2013).High salt intake has been found as responsible for 17-30% of hypertension and substantially increases the risk of blood pressurerelated cardiovascular diseases in normotensives (Geleijnse et al., 2005 andKearney et al., 2005).It has been reported that, 1.65 million annual deaths from cardiovascular events attributed to excess salt intake (Mozaffarian et al., 2014).Again, current world is facing a serious public health threat for tackling the burden of cardiovascular diseases as a major noncommunicable disease as well as the number one cause of global death.It has been estimated that 17.7 million people die annually around the world due to cardiovascular diseases occupying 31% of all global deaths (World Health Organization, 2017b).
On the other hand, people of Bangladesh are consuming more than threefold dietary salt (17gm/day) than the recommended level (<5gm/day) given by World Health Organization (Zaman et al., 2016a).Even, added salt intake behavior during meal is also remarkable.It has been reported that, 69-72% of Bangladeshi general population is habituated to use added salt during meal in the manner of Always-to-Rarely (Zaman et al., 2016a andMondal et al., 2017) though this prevalence was little less (66.3%) considering the same manner among the public health professionals like doctors and faculties (Zaman et al., 2016b).Moreover, NCD risk factors are initiated during the school age (The World Bank, 2011).Hence, it is very important to explore the dietary salt related information among students.
Therefore, this study was designed in order to assess the knowledge, attitude and behavior towards dietary salt among the medical and nonmedical undergraduate students in Dhaka city of Bangladesh.

Data and Methods
Study Design and Setting: A cross-sectional study was conducted in Dhaka city in 2016 among 280 adult (age≥18 years) medical and nonmedical undergraduate students to compare the knowledge, attitude and behavior regarding dietary salt intake between the groups.Each group comprised of equal number of students (140).Medical students were from MBBS and physiotherapy background, whereas nonmedical students were from business, law, engineering and pharmacy background.MBBS students were recruited from Shaheed Suhrawardy Medical College; physiotherapy students were from State College of Health Sciences; and other nonmedical students were from State University of Bangladesh, University of Development Alternative and Institute of Science and Technology.Institutions as well as the respondents both were selected purposively for this study.

Data Collection Instrument and Process:
A semi-structured questionnaire was developed using WHO Modified Salt Module of STEPS Questionnaire to collect data.And the data were collected by face-to-face interviews with the respondents.
Data Management and Analysis: After collection of all data, these were checked for completeness and consistency, and finally entered into SPSS-21 and analyzed.Descriptive statistics was used to illustrate the socio-demographic factors as well as the knowledge, attitude and behavior related factors regarding dietary salt intake, and comparative statistics like Chi-square test was used to illustrate the difference between the study groups.
All the ethical issues were maintained according to the guideline of Bangladesh Medical and Research Council (BMRC) and Volume 2, Issue 1, December 2017 both verbal and written informed consents were taken prior to data collection from each respondent.

Results:
Men dominated by three in every five of the respondents in both groups (medical, 59.3% and nonmedical, 64.3%).The mean age off the respondents was 22.0±2.0years (medical, 22.0±2.0years; nonmedical, 21.8±1.9years), whereas around three quarter of the respondents were aged between 20-24 years in both groups.Medical and nonmedical groups were dominated by 4 th and 3 rd year respectively.Most of the respondents had monthly income of BDT 30,000-50,000 in both groups (Table -1).
Regarding knowledge about salt intake, mixed results have been found for the perception towards individual's salt intake which didn't reflect significant difference between the groups (p, 0.364).Yet, medical students perceived more that they were used to take just the right amount of salt than the counterpart (51.4% vs. 60.7).Medical students also perceived more that too much salt could cause serious health problem which was significantly differed (p, 0.005).Regarding attitude toward individual's salt intake, lowering salt intake was important more among medical students than the counterpart reflecting significant difference (p, 0.040), [table-2].
Current study found that nearly two-thirds of overall students (64.3%) were used to take added salt during their meal, whereas nonmedical students were habituated more than the medical students ( 71  There was a significant difference of salt practice between the groups (p, 0.001).Always users were noticeably more in nonmedical group than the counterpart (17.9% vs. 5.0%), whereas the statistics was viceversa for sometimes users.The similar statistics was found also for high salt contained processed food intake behavior between the groups with significant difference (0.012).As Bangladeshi context, all of the respondents (100%) mentioned that salt was used in always manner during their food preparation (not shown in table).Again, study didn't found noticeable difference regarding the activities to control individual's salt practice except avoid eating out (p, 0.031) [table-3].

Discussion
Overall, 56.1% of the all undergraduate students of this study believed that they were used to take just the right amount of salt, whereas this proportion was lesser among the Bangladeshi general population reflecting 44.4% (Mondal et al., 2017).Again, 60.7% of the medical students believed the same, which was more than the doctors and faculties of Bangladesh as well as medical students of London and Angola expressing 29.3%, 47.7% and 56.1% respectively (Magalhães et al., 2015;Kabir et al., 2016;and Zaman et al., 2016b)).Overall, 84.6% students of this study mentioned that too much salt could cause serious health problem, whereas this proportion was lesser among the Bangladeshi general population reflecting 60.7% (Mondal et al., 2017).Again, 89.9% of the medical students believed the same, which was lesser than the doctors and faculties of Bangladesh as well as medical students of London and Angola expressing 93.5%, 93.9% and 99.2% respectively (Magalhães et al., 2015;Kabir et al., 2016;and Zaman et al., 2016b).Overall 54.5% students mentioned that lowering salt in diet is very important, whereas this  proportion was also lesser among the Bangladeshi general population reflecting 38.8% (Mondal et al., 2017).Again, 57.6% of the medical students believed the same, which was lesser than the doctors and faculties of Bangladesh as well as medical students of London and Angola expressing 72.8%, 65.9% and 91.9% respectively (Magalhães et al., 2015;Kabir et al., 2016;and Zaman et al., 2016b).
Nearly two-thirds of overall students (64.3%) were used to take added salt during their meal, whereas this prevalence was higher among the Bangladeshi general population reflecting ranged 69.0-72.5% (Mondal et al., 2017 andZaman et al., 2016a).Again, 57.1% of the medical students were used do the same, whereas this prevalence was also higher among the doctors and faculties of Bangladesh as well as medical students of London and Angola  expressing 66.3%, 78.7% and 75.6% respectively (Magalhães et al., 2015;Kabir et al., 2016;and Zaman et al., 2016b).Again, most of the students (47.1%) were used to take high salt contained processed food in sometimes manner, whereas this prevalence was higher than the Bangladeshi general population reflecting ranged 29.8% (Mondal et al., 2017).Total, 49.3% of the medical students were habituated with the same manner which was also higher than the doctors and faculties of Bangladesh as well as medical students of London expressing 26.6% and 38.6% respectively (Kabir et al., 2016 andZaman et al., 2016b).
The students of this study showed little less knowledge and attitude towards salt intake than the doctors and faculties of Bangladesh as well as medical students of London and Angola, whereas the practice of salt and salty food was with mixed scenarios.Yet, the current study population was with lesser mean age as well as with not having work experience than the counterparts, especially doctors and faculties of Bangladesh and medical students of London.

Conclusion
Current study revealed that medical students possessed more knowledge and showed more positive attitude towards dietary salt intake than the nonmedical students.Significant differences were found for perception on health effect of salt and importance of lowering salt.Nonmedical students were significantly more habituated in salt practice and high salt contained processed food intake behavior than the counterpart.Yet, health education program is needed for undergraduate students especially for the nonmedical background to encourage less dietary salt practice.