Chapter 2 – Literature Review
Chapter II
The Review of the Related Literature
Introduction
During the past decades, breakthroughs in the study of Vitamin D and findings pointing to its importance in maintaining health have been made. Apart from the found importance of Vitamin D in human skeletal development, further evidence is attributing the benefits of adequate Vitamin D to the development of other tissues in the body. In addition, the prior belief regarding the amount of Vitamin D needed in the body was changed encompassing new findings that the human body needs more Vitamin D than usually thought (Holick, 2004). Given the new developments on the study of Vitamin D, health issues are beginning to concern experts particularly in the Middle East region because of the perceived increasing number of Saudi Arabian population suffering from Vitamin D deficiency. It is ironic at some point that Saudi Arabians are experiencing Vitamin D deficiency, given that the region is a suitable environment for Vitamin D production because it is abundant with the most important building block in producing Vitamin D, which is sunlight. Early studies of the aforementioned issue points out factors that contributes to Vitamin D deficiencies among the Saudi Arabian population such as cultural traditions, skin pigmentation and changing Saudi Arabian landscape.
Brief History
The problem of Vitamin D deficiency started to gain attention when incidences of rickets became prevalent in the British Isles region where the densely populated urban areas has affected the amount of sunlight exposure on its inhabitants (Owen, 1889). From the historical findings it is apparent that insufficient exposure to sunlight is among the common causes of several bone related problems due to lack of Vitamin D in the body. Christie and Mason (2011) conducted a study to test the knowledge and to determine practices of female students in Saudi Arabia that leads to the Vitamin D deficiency. From the historical perspective of the study, Vitamin D deficiency was proved to be associated with poor musculoskeletal health otherwise called osteomalacia or rickets (Christie and Mason, 2011). The study employed the use of descriptive socio cultural approach, which encompasses the use of structured interviews with a focus group to quantify the frequency of practices, level of knowledge and attitude of female Saudi Arabian students regarding sun exposure and the relationship of vitamin D deficiency to prevalence of rickets.
The finding suggests that test subjects have minimal awareness of vitamin D deficiency despite knowing that it is essential in maintaining musculoskeletal health. The socio-cultural focus of the Christie and Mason (2011) study describes the occurrence of vitamin D deficiency due to cultural practices. It is known Islamic traditions require females to wear “Abayas” when going out in public, which covers the entire body including the hands from direct sunlight. Historical narratives provide rational to the long-standing Islamic traditions, which is currently considered as a factor in Vitamin D deficiency problems. The study conducted by Christie and Mason (2011) was able to provide a historical perspective on of the factors that directly relates to the exploration of vitamin D deficiency problem in Saudi Arabia.
Vitamin D Deficiency Among Saudi Arabians
It was established that cultural practices in Saudi Arabia is attribute to vitamin D deficiency. However, the findings in Christie and Mason (2011) study suggests that significant number of Saudi Arabians particularly woman are not totally aware of the effects of the problem in the body. The same assumption was made in the study conducted by Al-Mogbel (2012) in which the vitamin D status of Saudi women were measured to determine the extent of deficiency among the country’s female population. Al-Mogbel (2012) conducted the cross-sectional study of 500 participants and divided them according to age groups of 19 to 40 years old and 41 onwards. After acquiring approval from the ethical research committee of King Abdullah International Medical Center the study was carried out in the course of four months in which blood samples were taken from the participants for vitamin D measurement (Al-Mogbel, 2012).
A total of 465b females in mixed age groups were found to have lower vitamin D levels serum 25-OH-vitamin D < 75 mnol /L (Al-Mogbel, 2012). Since 95% of the tested samples are evidently lacking the essential building blocks to produce vitamin D, the next step is to determine the effects of the deficiency among the samples. A great majority of the sampled female population in Saudi Arabia has shown to have musculoskeletal complications ranging from subacute rheumatism, metabolic diseases, cardiovascular diseases, multiple sclerosis, neoplastic diseases and cancer (Al-Mogbel, 2012; Al-Mahroos et al., 2013). A similar study by Al-Mahroos et al. (2013) was also conducted to measure the prevalence of risk factors in vitamin D deficiency among men in Saudi Arabia. Using a similar quantitative methodology, it was found that vitamin D deficiency is also common among men in the Saudi Kingdom due to factors related to lack of exposure to sunlight (Al-Mahroos et al., 2013). High income and high BMI were among the predictors of vitamin D deficiency among men.
Furthermore, 364 out of 403 male subject or 90.3% have shown variations of deficiency effects described in Al-Mogbel (2012) study (Al-Mahroos et al., 2013). The study also revealed discrepancies in statistical results after analysis because one factor is not applicable to men as in women, which is the cultural practice of wearing veil. However, similar deficiency level was found in both men and women, which leads to the exploration of other predictors apart from BMI and lack of sun exposure. Al-Mahroos et al. (2013) study encompasses random selection of samples, which is composed of 72.8% or 265 Bahrainis and the rest of the samples are Saudi-based Asians and Europeans. A-Mahroos et al., (2013) study revealed significant variation of vitamin D deficiency levels among the sampled population showing Asians and Bahrainis having the highest deficiency levels. This finding introduced another contributing factor in vitamin D deficiency, which is skin pigmentation.
The abundant natural source of vitamin D apart from dietary intake is sunlight. Adequate exposure during the right time of the day and season of the year optimizes the body’s capability to produce adequate amount of vitamin D. However, skin pigmentation also plays a crucial role in vitamin D production. Alshahrani et al. (2013) conducted a study to determine the best time of sunshine in Riyadh, Saudi Arabia to get exposed to the sun for vitamin D production optimization. One of the factors pointed out in the study is the role of skin pigmentation in optimal vitamin D production. The melanin content of the skin was assumed to be blocking the absorption of solar UVB (290 to 315 nm), which is raw ingredient in vitamin D production in the body (Alshahrani et al., 2013). The photon absorbed in the epidermis is combined with 7-dehydrocholesterol existing in the plasma membrane (Alshahrani et al., 2013). The experimental method in the study replicates the reaction between sunlight photons and 7-dehydrocholesterol sealed under Argon in borosilicate ampoules in vitamin D production. Variations of light and shade were applied to the samples to depict skin coloration and other factors such as time, season, cloudy sky and atmospheric pollution (Alshahrani et al., 2013). The findings suggest that time of day, skin melanin content and seasons of the year influence the production of vitamin D due to variation in the sunlight absorption.
Symptoms Related to Vitamin D Deficiency
There is a reason why significant percentage of Saudi Arabian population is not aware that they have vitamin D deficiency. This is because the symptoms are highly correlated to more prominent health conditions, thus, vitamin D deficiency itself is often considered as an unforeseen causal factor. The association of vitamin D deficiency in the occurrence of rickets among Saudi Arabians is determinable based on a variety of symptoms. Al-Mutair, Nasrat and Russel (2012) studied the precursors to vitamin D deficiency by looking into CYP2R1 genetic mutation process. Secosteroid previtamin D converted by UV light is spontaneously rearranged to become the circulating vitamin form. However, the absence of key enzymes and loss of CYP2R1caused by genetic anomalies causes selective 25-hydroxyvitamin D deficiency (Al-Mutair, Nasrat and Russel, 2013). These findings are described through patient observation and administration of cholecalciferol 5,000 IU/d for patient 1 and doubled dosage of the same for patient 2 and both have vitamin D deficiency. The clinical observation encompasses reactive response of the patient to the optimization of vitamin D production by looking into occurred symptoms.
During the course of the observation, related symptoms were recorded including bone pain, which leads to physical activity restrictions. Other symptoms were more imminent in the observed patient such as difficulty in walking and bowing of the lower limbs. In addition, molecular genetic analysis of the patient’s CYP2R1 revealed genetic mutations, which was a result of improperly spliced mRNA leading to truncated CYP2R1 proteins and unstable mRNA (Al-Mutair, Nasrat and Russel, 2013). The findings of the study gave a highly technical evaluation of vitamin D deficiency symptoms, which is apparent in the occurrence of bone-related problems, aching and deformity.
Ali, Amin and Al-Ali (2012) also conducted a similar study to determine the symptoms of vitamin D deficiency in Saudi Arabian population through a structure interview of medical history and blood laboratory testing. The objective is to create a baseline for cross-analysis in which vitamin D levels in the blood were measured for adequacy. There were 94 female college students that participated in the study and 63% were found to have vitamin D deficiency and the same percentage is consistent with complaints about fatigue (Ali, Amin and Al-Ali, 2012). In addition, clinical diagnosis revealed that portion of the subjects with vitamin D deficiency is also suffering from combinations of muscle and bone pain, stress, fibromyalgia and chronic fatigue syndrome (Ali, Amin and Al-Ali, 2012). Furthermore, 55.6% of the subjects with vitamin D deficiency are also complaining about episodes of insomnia, lumbago and rheumatic symptoms. These findings suggest the number of predictors of vitamin D deficiency, which are symptoms that are also related to other types of illnesses.
Practical Approach in Improving Vitamin D Deficiency
Several studies suggest different approach in improving vitamin D deficiency. The study by Naeem et al. (2011) measured the prevalence of vitamin D deficiency among the population of Qassim region in Saudi Arabia through blood sampling and administering questionnaires. The study revealed similar findings in related research, which encompasses significant number of Qassim population with vitamin D deficiency (Naeem et al., 2011). However, the study also suggests practical methods to combat vitamin D deficiency apart from optimum exposure to direct sunlight. The serum vitamin D level among the sampled population of 180 has improved after following a formulated dietary plan consisting of eggs, liver, fish and cheese (Naeem et al., 2011). These foods are found to contain the essential protein enzymes in producing vitamin D in the body. The findings suggest one practical approach, which is a balanced and healthy diet. Food items such as dried mushrooms are naturally been fortified with vitamin D (Ali, Amin and Al-Ali, 2012).
Given the cultural practices in the Islamic world, it would be an immense challenge for the Saudi Arabian women to change their traditions for the sake of the vitamin D deficiency. Therefore, recommendations for practical improvement of the deficiency condition can be in a form of consuming vitamin D rich food (Naeem et al., 2011). In addition, public education and awareness are also crucial in keeping the rest of Saudi Arabians free from deficiency with the help of the local health government unit in terms of information dissemination. Naeem et al. (2011) mentioned in her study that it is not necessary to expose the entire body to direct sunlight in order to optimize vitamin D production. Having the arms or legs exposed for at least 30 minutes with the absence of sunblock applications is enough to allow the body to produce enough vitamin D (Naeem, et al., 2011). Saudi Arabia’s ministry of health could also impose mandatory fortification of vitamin D among the locally processed food in the country. Other practical approach can be in a form of taking vitamin D supplements and exercise.
Summary
Vitamin D deficiency constitutes both short and long term health problems when not immediately addressed. Previous researches indicate significant number of Saudi Arabians with vitamin D deficiency due to number of factors including cultural practices and lack of awareness. Uncontrollable factors such as skin pigmentation can be addressed by exposing the sunlight at predetermined time of the day for optimal results. On the other hand, predictors of deficiency symptoms can be resolved through practical approach as suggested by previous researches.
Chapter III Overview
The next part of this study will comprise of discussion, conclusion, and implications for practice, recommendations, and further study. The discussion encompasses thorough evaluation of the concepts in Vitamin D deficiency, which includes analysis of the factors leading to the perceived deficiency among the Saudi Arabia population. The importance of exploring this area is to strongly establish the causes and the attributed factors pointing to the current issue of vitamin D deficiency. In addition, discussing the significant factors on the issue will provide scientific perspectives on the issue, which will validate the formulated hypotheses and findings of the study. Discussing the important elements in Vitamin D deficiency study will frame the components that are paramount to the conclusion of the study. At this point of the study, it can be concluded that Vitamin D deficiency is primarily due to socio-cultural factors that prevents Saudi Arabians from getting enough exposure to sunlight and skin pigmentation. The relevant findings of the study constitute significant implications to practice due to the changes on people’s perception about the importance of Vitamin D. However, the study itself encompasses limitations, which requires further study such as the possibilities of socio-cultural change that will enable greater number of Saudi Arabians particularly females to get adequate sun exposure.
References
Al-mahroos, F. T., Al-Sahlawi, H. S., Al-Amer, E., Radhi, H. T., & Khalaf, S. (2013). Prevalence and Risk Factors of Vitamin D Deficiency among Men. Bahrain Medical Bulletin, 35(3), 1-8.
Al-Mogbel, E. S. (2012). Vitamin D status among Adult Saudi Females visiting Primary Health Care Clinics. International Journal of Health Sciences, Qassim University, 6(2), 99-107.
Ali, A., Amin, L., & Al-amin, A. (2012). Vitamin D level Among Female Students in College of Nursing in Saudi Arabia and its Relation to Students’ Symptoms. Journal of American Science, 8(11), 132-138.
Alshahrani, F. N., Almalki, M. S., Aljohani, N., Alzahrani, A., Alsaleh, Y., & Holick, M. F. (2013). Vitamin D Light side and best time of sunshine in Riyadh, Saudi Arabia. Dermato-Endocrinology, 5(1), 177–180.
Christie, F. T., & Mason, L. (2011). Knowledge, attitude and practice regarding vitamin D deficiency among female students in Saudi Arabia: a qualitative exploration. International Journal of Rheumatic Diseases.
Mutair, A. N., Nasrat, G. N., & Russell, D. W. (2012). Mutation of the CYP2R1 Vitamin D 25-Hydroxylase in a Saudi Arabian Family with Severe Vitamin D Deficiency. J Clin Endocrinol Metab, 97(10), 1-4. doi:10.1210/jc.2012-1340
Naeem, Z., AlMohaimeed, A., Sharaf, F., Ismail, H., Shaukat, F., & Inam, S. (2011). Vitamin D status among population of Qassim Region, Saudi Arabia. International Journal of Health Sciences, Qassim University, 5(2), 116-124.
Owen, I. (1889). Geographical distribution of rickets, acute and subacute rheumatism, chorea, cancer and urinary calculus in the British Islands. British Medical Journal, 1, 113.
