Coverage of Iodized Salt and Associated Factors at Household Level in Goba Town, Bale Zone, South East Ethiopia, 2015

Background: Iodine Deficiency Disorder is one of the biggest worldwide public health problems of today. Fortification of salt with iodine is recognized as the most simple and cost effective strategy to achieve recommended daily intake of iodine. Hence this study wanted to assess coverage of adequately iodized salt & associated factors at household level in Goba town. Methods: Community based cross-sectional survey conducted among 598 households using concurrent qualitative & quantitative method in Goba town, South East Ethiopia from August 1-30, 2013. Data were collected by trained diploma nurses supervised by BSC nurses. Interviewer administered questionnaire & rapid field test kits were used to collect the data. Data were cleaned, coded & entered in to EPI Info and exported to SPSS for analysis. Data were summarized in tables & charts. Variables having p value ≤ 0.2 in univariate analysis were entered into multivariate logistic regression to test association between the outcome and predictable variables at p value ≤ 0.05. Results: From a total of 596 households included in the study, only 30% of the households were covered by adequately iodized salt. Regarding the associated factors, about coverage of adequately iodized salt, not exposing to sunlight, purchasing from supermarkets or big shops & perceived cheap were found to be statistically significant with AOR (95% CI) = 2.20 (1.31, 3.60), 1.91 (1.10, 3.34), 1.70 (1.10, 2.0) respectively. Conclusion: Coverage of adequately iodized salt at household level was low (30%) in Goba town. The main associated factors were not exposing to sun light, purchased from big shop or supermarket & perceived cheap. Households’ should be educated about proper handling of iodized salt at household level.


Background
Iodine presents in the body in a minute amounts, mainly in the thyroid gland. Its main role is in the synthesis of thyroid hormones. When requirements are not met, thyroid hormone synthesis is impaired, resulting in hypothyroidism and a series of functional and developmental abnormalities grouped under the heading of "Iodine Deficiency Disorders [1]. Failure to have adequate iodine leads to insufficient production of thyroid hormones, which affects different parts of the body, particularly muscle, heart, liver, kidney, and the developing brain. Inadequate hormone production adversely affects these tissues resulting in the disease states known collectively as iodine deficiency disorders [2]. The WHO/UNICEF/ICCIDD recommends that iodine concentration in salt at the point of production should be within the range of 20-40 mg of iodine per kg of salt (i.e. 20-40 ppm of iodine) in order to Provide 150 mcg of iodine per person per day [3]. The actual availability of iodine in the iodized salt at the consumer level can vary over a wide range as a result of variability in the amount of iodine added during the iodization process, uneven distribution of iodine in the iodized salt, the extent of loss iodine due to salt impurities, packaging & environmental conditions during storage & transportation, loss of iodine due to washing & cooking process in the household, & the availability of non-iodized salt from unconventional marketing sources [4]. Iodine deficiency is a major global public health problem, particularly for young children & pregnant women. The most serious effect of iodine deficiency is mental retardation. It is one of the world's major causes of preventable cognitive impairment, posing a threat to social & economic development of countries [5].

Study Design, Period & Setting
Community based cross-sectional quantitative study were used. The study was conducted from August 1 -30, 2013 in Goba town which is located in the southeastern part of the country along Addis Ababa Goba road which is 445 via Assela. Goba is one of the highland towns situated at the foot of Bale Mountain chain which is characterized by rugged terrain landscape. The relief of Goba town was found between 2510 and 2800 meters above sea level & the average elevation being about 2655 meters above sea level. The total populations were 41,328 of which male accounts 19,643 (47.5%), & female being 21,685 (52.5%). The largest proportion of population of Goba town were Orthodox (71.9%), Muslim (21%), followed by others (7.1%) [24].

Study Population, Sample Size & Sampling Procedure
The study population was selected households in the selected kebeles in Goba town. Member of households whose age was 18 & above & more responsible in purchasing food items and mostly involved in food preparation were interviewed. The sample size was determined by using formula for estimating single population proportion.
The following assumptions were used to obtain the optimum sample size. P = proportion of households consuming adequately iodized salt (15%) [10]. Z statistic =1.96, d = the maximum allowable error taken (3%), & non-response rate 10% giving final sample size 598 households. After identifying the center of the town (market area) the starting point for sampling, the east direction were identified randomly & the first household number was selected by using lottery method & then by systematic random sampling technique every 14 th household was visited to get the required number of study subjects in each kebeles.

Data Collection Procedures
Data were collected using pretested interviewer administered structured questionnaires on respondents: educational level, occupation, availability of iodized salt, monthly household income, environmental factors, knowledge, attitude, & perception on price of iodized salt. In addition to the training given to the data collectors, the questionnaire was pretested 5 days before the actual data collection days in one of the kebeles in Robe town which is 12 kilometers away from Goba town on 5% of the total sample size. Moreover data collection & completeness of filled questionnaire was checked in the field. To assess the coverage of iodized salt at household level, a teaspoonful of salt sample used for cooking was tested by using rapid test kit obtained from UNICEF & Micronutrient Initiative. Six trained diploma nurses and two supervisors were recruited during data collection.

Data Management and Analysis
After data collection, each questionnaire was checked for completeness and consistency by supervisors. Data were cleaned using computer software program & entered in to epi-info version 3.5.1 & exported to SPSS version 20.0 for analysis. Data summarized with tables & charts. Variables having p-value ≤ 0.2 in the univariate analysis were entered in to multivariate logistic regression models to control confounding factors. Then odds ratio at 95% confidence interval was used to show association between dependent and independent variables. P value of ≤ 0.05 considered statistically significant in the multivariate analysis. Participants who respond above mean for seven knowledge questions were considered to have sufficient knowledge & who respond below the mean for seven knowledge questions were considered to have insufficient knowledge. Participants who respond above the mean for seven attitudinal questions were considered to have favorable attitude & who respond below the mean for seven attitudinal questions were considered to have unfavorable attitude. Adequately iodized salt at household level: is defined as salt sample which had ≥15 parts per million (PPM) of iodine during salt sample test.
Data quality assurance was done during questionnaire designing, data collection & data entry. Questionnaire was logically sequenced, free of scientific terms, non-leading and pretested. Data was checked for its consistency and completeness every day on the sites by supervisors.

Ethical Considerations
Ethical clearance was obtained from the Ethical Committee of Bahir Dar University, College of Medicine & Health Science. Letters of permission was gained from Oromia Regional Health Bureau, Bale Zone Health Bureau and Goba Town Health Office. Informed consent was obtained from participants involved in the study, from head of household & study participants. The participants were allowed to consider their participation and given the opportunity to withdraw from the study at any point in the course of the study if they wished to do so. Participants' name or personal identifier was not included in the written questionnaires to ensure participants' confidentiality. Health education on the importance and source of iodized salt and proper handling of it at household level was given by the data collectors for households after data collection.

Results
Socio demographic characteristic of the respondents: A While 246 (41.3%) of the respondents exposed salt to sunlight when it becomes humid. Concerning washing practice, 62 (10.4%) of respondents reported that they washed salt to remove impurities. Regarding the time when the salt is added during cooking, 341 (57.2) of respondents reported that they add salt at the end of cooking just before the dish is out of fire (Table 2).

Factors Associated with Coverage of Adequately Iodized Salt at Household Level
The investigation on the presence of association between associated factors and coverage of adequately iodized salt revealed the following results: Having family size greater than five, storing in a dry place, purchasing from supermarket or big shops & using cover for salt containers, storing salt at home for less than 2 months, not exposing to sunlight, not washing before consumption & perceived price were significantly associated variables with coverage of adequately iodized salt at household level during univariate analysis.
But, only purchasing from big shops or supermarkets, not exposed to sun light & perceived cheap were significantly associated with coverage of adequately iodized salt at household level in multivariate analysis. Regarding source of purchase, those who purchased iodized salt from big shops or supermarkets were 1.91 times more likely to have adequately iodized salt at household level than those who purchased from small shops & market (AOR =1.91, 95%CI (1.10, 3.34)) Regarding exposure to sun light those who did not expose to sunlight were 2.20 times more likely to have adequately iodized salt at household level than those who exposed to sun light (AOR =2.20, 95%CI (1.31, 3.60)). Regarding perceived price of iodized salt those who perceived iodized salt as cheap were 1.70 times more likely to have adequately iodized salt at household level than those who perceived it expensive (AOR =1.70, 95% CI (1.10, 2.60)) ( Table 3).

Discussion
This study revealed that only 30% of the households in Goba town were covered by adequately iodized salt (≥15ppm) which was very low compared to study conducted among 8 states of India (51%), Lucknow district of India (64.2%), & West Bengal (73%) district of India [11][12][13]. In Cameron, Kenya, Rwanda, Zimbabwe, Lesotho & Tanzania households were consuming 85-92% of adequately iodized salt, this might be due to availability & accessibility of iodized salt in the market, legislation & policies to fortify salt with iodine, regular follow up & monitoring regarding utilization of iodized salt in these countries. Compared to these countries the study area had low coverage of adequately iodized salt (30%), but better than Sudan (1%), Niger (15%), Senegal (16%), Pakistan (17%), Afghanistan (28%) [19]. The finding was also slightly high when compared to National nutrition baseline survey of Ethiopia 2009 (5%), EDHS 2011 report of the national coverage of iodized salt in Ethiopian 15.4% & Oromia region 17.4%, Bahirdar (24.9%), Gondar (28.9%) [10,21,22]. This difference might be study area difference as EDHS were conducted both in urban & rural setting but this study conducted in urban setting. Since Urban dwellers are expected to use iodized salt compared to rural dwellers as data from EDHS 2011 report.
Regarding factors associated with coverage of adequately iodized salt, not exposing to sunlight was associated with the coverage of adequately iodized salt at household level. Findings from qualitative study also showed that salt samples from households not exposing to sun light were found to have adequately iodized salt compared to households exposing salt to sun light. Study conducted in New Delhi documented that there was about 31% of loss iodine from iodized salt when exposed to sun light [26]. Similar study conducted in London also revealed that exposure to sunlight was associated with loss of iodine level of salt due to the volatile nature of iodine content from salt by heat [27]. Similar study done in Kazakhstan revealed that iodine from iodized salt losses its content gradually when exposed to sun light [28]. Study conducted in Gondar town also revealed that not exposing to sun light was significantly associated with the availability of adequately iodized salt at household [23].
Purchasing from big shop/supermarkets were associated with the coverage of adequately iodized salt at household level, this might be due to proper storage practice in the supermarket than in market & small shop. Findings from qualitative study also showed that being purchased from supermarkets /big shops found to have adequately covered iodized salt compared to salt from small shops & markets. Study done in Gondar town showed that from households whose salt samples tested to have adequately iodized salt, majority of them had got iodized salt from supermarkets [23].
Households who perceived iodized salt as cheap were more likely to have adequately iodized salt at household level as they might be more likely to afford to buy iodized salt than households who perceived it expensive. As this might be due to difference on socio economic status. Findings from qualitative study showed that the major reasons for not using iodized salt by the households were the price of iodized salt which was expensive compared to ordinary salt. Few respondents mentioned that reasons for using iodized salt were it is finer in size, easily dissolved & palatable. This finding is similar for the study conducted in Cambodia found that reasons for using refined salt were "already refined ", easy to dissolve & good to add in a soup & saltier than coarse salt & also majority of the respondents added salt at beginning during cooking of food [29]. Improper practice (i.e. Washing salt before consumption would reduce potential iodine added to the salt) among respondents identified as a major problem for inadequate availability of iodized salt at household level which was similar for study conducted in Haiti that most Haitians wash salt before consumption to remove debris & impurities [30].

Limitation of the Study
This study used rapid field testing kit to determine availability of adequately iodized salt from salt samples which did not include titration level of iodine & urinary iodine concentration testing of iodine to determine body iodine level.

Conclusion & Recommendations
The proportion of households covered by adequately iodized salt in Goba town was very low (30%) compared to the internationally recommended value to control IDD (90% & above). Perceived cheap in price, not exposing to sun light & being purchased from big shop or supermarket were factors significantly associated with availability of adequately iodized salt at household level in Goba town. Households should be educated about proper handling of iodized salt at household level to achieve universal salt iodization by Goba town health office.