Risk factors of low vitamin D status in adolescent females in Kuwait: implications for high peak bone mass attainment

Poor dietary consumption and limited sun exposure are risk factors for vitamin D deficiency in premenopausal Kuwaiti women: A cross-sectional study

Background: Low serum vitamin D levels are reported constantly among females living in the Arabian Gulf countries, presumably due to their lifestyle, which limits direct sun exposure. Because Vitamin D deficiency has been implicated in a wide range of ailments, healthy females with the deficiency might be at risk for developing many health problems. Thus, the aim was to assess lifestyle risk factors for vitamin D deficiency in healthy women in Kuwait. Methods: A total of 104, disease-free, premenopausal women were recruited for assessment of their serum 25OHD and intact PTH levels. Physical examination, blood withdrawal and interviewer-administered questionnaires were used to collect the relevant data. Associations were detected statistically using nonparametric tests and logistic regression was used to identify risk factors for vitamin D deficiency. Results: Vitamin D deficiency ( < 25 nmol/L) occurred in 84.6%, and hyperparathyroidism ( ≥ 6.9 pmol/L) occurred in 25% of women, among which all were vitamin D deficient. Significant risk factors of vitamin D deficiency were nondaily milk intake (OR:25, CI%:4.2-147), no fish intake (OR:5, CI%:1-22.8), and no weekend sun exposure (OR:8.2, CI%:1.28-52.6). Having PTH ≥ 6 pmol/L was also associated with a higher likelihood of having vitamin D deficiency. Conclusion: Vitamin D deficiency is very common in disease-free, premenopausal Kuwaiti women and can be avoided by improving food consumption and obtaining more sun exposure.

Impact of high latitude, urban living and ethnicity on 25-hydroxyvitamin D status: A need for multidisciplinary action?

The effects of urban living on health are becoming increasingly important, due to an increasing global population residing in urban areas. Concomitantly, due to immigration, there is a growing number of ethnic minority individuals (African, Asian or Middle Eastern descent) living in westernised Higher Latitude Countries (HLC) (e.g. Europe, Canada, New Zealand). Of concern is the fact that there is already a clear vitamin D deficiency epidemic in HLC, a problem which is likely to grow as the ethnic minority population in these countries increases. This is because 25-hydroxyvitamin D (25(OH)D) status of ethnic groups is significantly lower compared to native populations. Environmental factors contribute to a high prevalence of vitamin D deficiency in HLC, particularly during the winter months when there is no sunlight of appropriate wavelength for vitamin D synthesis via the skin. Also, climatic factors such as cloud cover may reduce vitamin D status even in the summer. This may be further worsened by factors related to urban living, including air pollution, which reduces UVB exposure to the skin, and less occupational sun exposure (may vary by individual HLC). Tall building height may reduce sun exposure by making areas more shaded. In addition, there are ethnicity-specific factors which further worsen vitamin D status in HLC urban dwellers, such as low dietary intake of vitamin D from foods, lower production of vitamin D in the skin due to increased melanin and reduced skin exposure to UVB due to cultural dress style and sun avoidance. A multidisciplinary approach applying knowledge from engineering, skin photobiology, nutrition, town planning and social science is required to prevent vitamin D deficiency in urban areas. Such an approach could include reduction of air pollution, modification of sun exposure advice to emphasise spending time each day in non-shaded urban areas (e.g. parks, away from tall buildings), and advice to ethnic minority groups to increase sun exposure, take vitamin D supplements and/or increase consumption of vitamin D rich foods in a way that is safe and culturally acceptable. This review hopes to stimulate further research to assess the impact of high latitude, urban environment and ethnicity on the risk of vitamin D deficiency.

Awareness of medical students about vitamin D deficiency at Ahfad University for women, Sudan

Vitamin D deficiency is not only associated with rickets and osteomalacia, but also with several chronic diseases, such as cancer, ischaemic heart disease, and type 1and 2 diabetes mellitus. Worldwide, an estimated one billion people suffer from vitamin D deficiency. The prevalence of this problem is unknown in Sudan due to scarcity of research in this particular area of concern. The present study aimed to assess the awareness of vitamin D deficiency through the knowledge of the importance of vitamin D, the link to diseases, vitamin D resources and the importance of dietary supplements, in addition to assessing the sun exposure habits in a sample of female Sudanese medical students. It is a descriptive cross-sectional community-based study, conducted at Ahfad University for Women, Omdurman, Sudan. More than half (56 %) of the participants were aged 21-25 years and 30% were in the second academic class. The majority of the participants were aware of the importance of vitamin D; however, the awareness of relating it to the chronic diseases was poor. Overall, 61.9% declared that vitamin D supplementation is important, and sun exposure habits were good (64.5% didn't use sunblock and 87.6% get exposed for more than 10 minutes/day). There was significant association between the age categories and exposure to the sun without sunblock on a daily basis (p value = 0.007).

The Effect of Clothing on Vitamin D Status, Bone Turnover Markers, and Bone Mineral Density in Young Kuwaiti Females

Many Arab women in the Gulf region cover their bodies for cultural and religious reasons, limiting the skin's exposure to sunlight and therefore its ability to synthesize vitamin D. The aim of this study is to determine whether the clothing style of Kuwaiti premenopausal women affects their vitamin D status, bone marker expression, and bone density. Three groups of healthy unmarried single Kuwaiti females (20-35 years old; n=30 per group) were recruited randomly from the general community: a control group who wear Western-style clothing (unveiled group), a group who wear a hejab that covers the whole body except for the face and hands (hejab group), and a group who wear a black veil with the entire body covered (veiled group). Bone mineral density (BMD), bone markers (procollagen type 1 N-terminal propeptide [P1NP], osteocalcin, and β-CrossLaps), 25-hydroxy vitamin D, intact parathyroid hormone [iPTH], and calcitonin were measured. The bone marker osteocalcin was significantly higher in the hejab group compared to the control group, whereas P1NP and β-CrossLaps were significantly higher in the veiled group compared to the control group. 25-hydroxy vitamin D, iPTH, calcitonin, and BMD were not significantly different across the three groups despite the observed elevation in bone turnover markers. The majority of participants in all three groups exhibited vitamin D deficiency; however, the lowest vitamin D levels were observed among the hejab and veiled participants. These findings suggest that clothing style may contribute to vitamin D deficiency in young Kuwaiti women.

Physical inactivity, gender and culture in Arab countries: a systematic assessment of the literature

Background

Physical inactivity is associated with excess weight and adverse health outcomes. We synthesize the evidence on physical inactivity and its social determinants in Arab countries, with special attention to gender and cultural context.

Methods

We searched MEDLINE, Popline, and SSCI for articles published between 2000 and 2016, assessing the prevalence of physical inactivity and its social determinants. We also included national survey reports on physical activity, and searched for analyses of the social context of physical activity.

Results

We found 172 articles meeting inclusion criteria. Standardized data are available from surveys by the World Health Organization for almost all countries, but journal articles show great variability in definitions, measurements and methodology. Prevalence of inactivity among adults and children/adolescents is high across countries, and is higher among women. Some determinants of physical inactivity in the region (age, gender, low education) are shared with other regions, but specific aspects of the cultural context of the region seem particularly discouraging of physical activity. We draw on social science studies to gain insights into why this is so.

Conclusions

Physical inactivity among Arab adults and children/adolescents is high. Studies using harmonized approaches, rigorous analytic techniques and a deeper examination of context are needed to design appropriate interventions.

Electronic supplementary material

The online version of this article (10.1186/s12889-018-5472-z) contains supplementary material, which is available to authorized users.

The Prevalence of Hypovitaminosis D and Its Associated Risk Factors Among Women of Reproductive Age in Saudi Arabia: A Systematic Review and Meta-Analysis

Vitamin D deficiency is currently a worldwide epidemic. Middle Eastern countries, including Saudi Arabia, have high vitamin D deficiency prevalence, most prominently among women, despite their plentiful year-round sunshine. Previous research investigating vitamin D status among Saudi women of reproductive age (15-49 years) is scarce, and no study has used a nationally representative sample, so this review quantified overall hypovitaminosis D prevalence among women in Saudi Arabia and explored the associated risk factors. The Web of Science, Scopus, and Medline databases were searched for prior studies in Saudi Arabia exploring vitamin D status among women of reproductive age, published between January 1, 2000 and May 25, 2017. Data were extracted from the identified studies, and a random effects model meta-analysis established the overall hypovitaminosis D prevalence. The initial search yielded 223 possibly relevant articles; 13 were confirmed as eligible, with samples totaling 2877 women aged between 15 and 49 years. Meta-analysis revealed a mean serum 25-hydroxyvitamin D, 25(OH)D, level of 13.1 ng/mL (95% confidence interval [CI]: 11.6-14.6) and an overall prevalence of hypovitaminosis D, defined as 25(OH)D < 30 ng/mL, of 77.4% (95% CI: 63.2-87.3), mostly due to insufficient sunlight exposure and low dietary vitamin D intake. There is therefore a need for a national strategy to raise vitamin D levels among women in Saudi Arabia by advising them on natural vitamin D sources, and recommending the timing and duration of sun exposure, while also defining a national approach to vitamin D fortification and supplementation.

Vitamin D levels in schoolchildren: a cross-sectional study in Kuwait

Background

Ongoing studies in the Middle East, particularly in the Arabian Gulf countries, have reported extremely low levels of serum vitamin D across age and gender. In Kuwait, vitamin D deficiency is prevalent in adolescent girls and in adult women. A number of risk factors have been reported, among which gender, age, and obesity are a few. Because adequate vitamin D status is necessary to promote bone mineral accrual in childhood, and because low vitamin D levels have been associated with a wide range of health problems, there is concern that growing children with low vitamin D may be at higher risk for developing diseases. The aim of this study was to assess vitamin D levels in elementary schoolchildren.

Methods

Kuwaiti schoolchildren were recruited and assessed for their serum vitamin D, 25(OH)D, parathyroid hormone (PTH) and adjusted serum calcium (adj-Ca). Anthropometric measurements and data on lifestyle and health status were recorded during an interview.

Results

In a total of 199 schoolchildren, median (IQR) age was 8.5 (7.0–9.5 years), 25(OH)D was 30 (22–39 nmol/L), PTH was 4.7 (3.8–5.9 pmol/L), and adj-Ca was 2.39 (2.33–2.44 mmol/L). Boys had higher levels of 25(OH)D (18.3% vs 6.6% had levels ≥50 nmol/L) and lower levels of PTH (94.6% vs 80.2% had levels <7 pmol/L) than girls. Significant risk factors for 25(OH)D levels <25 nmol/L included being ≤8.5 years old (OR 4.95, 95% CI: 1.92–12.74), having PTH ≥7 pmol/L (OR 2.28, 95% CI: 1.17–4.46), being female (OR 2.44, 95% CI: 1.22–4.88), and being overweight or obese (OR 2.18, 95% CI: 1.11–4.26).

Conclusions

The results show relatively low levels of 25(OH)D in young schoolchildren in Kuwait, with lower levels in girls. Given the association of 25(OH)D with a wide range of ailments, it is necessary to further examine the causes and risk factors of low vitamin D in this age group to prevent associated health problems.

Computational model for vitamin D deficiency using hair mineral analysis

Vitamin D deficiency is prevalent in the Arabian Gulf region, especially among women. Recent studies show that the vitamin D deficiency is associated with a mineral status of a patient. Therefore, it is important to assess the mineral status of the patient to reveal the hidden mineral imbalance associated with vitamin D deficiency. A well-known test such as the red blood cells is fairly expensive, invasive, and less informative. On the other hand, a hair mineral analysis can be considered an accurate, excellent, highly informative tool to measure mineral imbalance associated with vitamin D deficiency. In this study, 118 apparently healthy Kuwaiti women were assessed for their mineral levels and vitamin D status by a hair mineral analysis (HMA). This information was used to build a computerized model that would predict vitamin D deficiency based on its association with the levels and ratios of minerals. The first phase of the proposed model introduces a novel hybrid optimization algorithm, which can be considered as an improvement of Bat Algorithm (BA) to select the most discriminative features. The improvement includes using the mutation process of Genetic Algorithm (GA) to update the positions of bats with the aim of speeding up convergence; thus, making the algorithm more feasible for wider ranges of real-world applications. Due to the imbalanced class distribution in our dataset, in the second phase, different sampling methods such as Random Under-Sampling, Random Over-Sampling, and Synthetic Minority Oversampling Technique are used to solve the problem of imbalanced datasets. In the third phase, an AdaBoost ensemble classifier is used to predicting the vitamin D deficiency. The results showed that the proposed model achieved good results to detect the deficiency in vitamin D.

Fractures in Kuwait: incidence and distribution

The absence of descriptive epidemiological data on the frequency and distribution of fractures in a population is serious and may underestimate the actual importance of this public health problem. In this study, we report the crude and standardized incidence rates of fractures in the population of Kuwait during the period 2009-2012. Using the Ministry of Public Health's national registry, demographic data of all fracture cases between 2009 and 2012 were retrieved. These were further categorized into fractures at the hip or any other sites. Average annual incidence rates were calculated and standardized using the world's population in 2010 as a reference. Thus, 18,119 fractures among males and 6,362 among females were recorded. The overall estimated annual incidence rates of fractures per 100,000 person-years were 207 for males and 111.8 for females. Moreover, 13.3% of all fractures were in the hip, with incidence rates of 24.8 for males and 18.9 for females; while 86.7% were in other sites, with corresponding incidence rates of 182.2 and 92.8, respectively. The age-specific fracture incidence rates in females remained below the corresponding rates of males until ≥50 years of age, after which the female age groups showed successively higher rates. The age-standardized incidence rates for all fractures (hip and other sites) were 247.4 for males, 175.4 for females, and 216.2 for both sexes. The burden of this major public health challenge is set to rise, and such population-based incidence data call for an urgent need for action to reduce the projected human impact and socioeconomic costs of fracture.

Prevalence of vitamin D deficiency and association with metabolic syndrome in a Qatari population

OBJECTIVES

Despite long hours of sunlight in Qatar and other regions of the Middle East, vitamin D deficiency has been rising. In parallel, the prevalence of metabolic syndrome has also been increasing in Qatar. Vitamin D levels have been associated with metabolic syndrome but the data are inconsistent and no studies have addressed these inter-relationships in a Middle Eastern population where the prevalence of these conditions is high. The objective is to investigate the prevalence of vitamin D deficiency and its association with metabolic syndrome and its components in the Qatar Biobank population.

METHODS

A cross-sectional study of 1205 participants (702 women and 503 men) from the Qatar Biobank, comprising Qataris and non-Qataris between the ages of 18 and 80 years, was used to perform multivariate linear regression analyses to examine the association between metabolic syndrome and prevalence of vitamin D deficiency (defined as <20 ng ml-1 serum vitamin D levels) adjusting for age, sex, ethnicity, season of blood collection, physical activity and education. Odds ratios and 95% confidence intervals were calculated for all analyses.

RESULTS

Approximately 64% of participants were vitamin D deficient (<20 ng ml-1) with more men being deficient (68.6%) than women (61.3%). Serum vitamin D was 8% lower in individuals with metabolic syndrome (RR: 0.92, 95%CI: 0.87-0.98, P-value: 0.01) compared to individuals without metabolic syndrome. Waist circumference and HDL as well as high triglyceride levels were also significantly positively associated with vitamin D deficiency. No association was found between the other components of metabolic syndrome or diabetes and the presence of vitamin D deficiency.

CONCLUSIONS

Vitamin D deficiency is prevalent in this Qatari population. Presence of metabolic syndrome was associated with presence of vitamin D deficiency. Future prospective studies need to be conducted to investigate the potential for causality.

Prevalence and Predictors of Hypovitaminosis D Among Female University Students in Tabuk, Saudi Arabia

BACKGROUND

A high hypovitaminosis D prevalence has repeatedly been reported in Middle Eastern countries. Previous data regarding the vitamin D status of young women in Saudi Arabia and the related hypovitaminosis D risk factors are scarce, so this research assessed hypovitaminosis D prevalence and its risk factors among apparently healthy female university students in Tabuk, Saudi Arabia.

METHODS

This cross-sectional research used a convenience sample of healthy female students (n = 180) aged between 19 and 25 years in May 2016. Information was gathered on the participants' sociodemographics, health, lifestyle, dietary intakes, anthropometry, and serum 25-hydroxyvitamin D (25(OH)D), and a logistic regression analysis was performed to assess hypovitaminosis D risk factors.

RESULTS

The sample's hypovitaminosis D prevalence (25(OH)D <30 ng/mL) was 80.6%. The main determinants of hypovitaminosis D were as follows: urban residence (odds ratio [OR] = 6.54; 95% confidence interval [CI], 2.74-5.63), rare sun exposure (OR = 6.14; 95% CI, 2.15-17.55), and insufficient vitamin D intake (OR = 2.50; 95% CI, 1.07-5.81).

CONCLUSIONS

The findings emphasize that despite plentiful sunshine, Saudi Arabia and the Middle East face a vitamin D deficiency epidemic. Vitamin D status must therefore be assessed at the national level so that strategies aimed at boosting vitamin D levels can be instigated.

Association of self-reported symptoms with serum levels of vitamin D and multivariate cytokine profile in healthy women

BACKGROUND

Although a large number of studies have investigated possible relationships among serum levels of vitamin D or cytokines with disease progress and prognosis, similar studies on self-reported symptoms are still controversial. The overall objective of this study was to look into the association between serum levels of vitamin D or cytokines with self-reported symptoms related to musculoskeletal pain, sleep disorders, and premenstrual syndrome (PMS) in healthy adult women.

SUBJECTS AND METHODS

Venous blood samples were collected from 117 healthy adult women, and serum levels of vitamin D, pro-inflammatory cytokines (IL-1β, IL-6, IL-8, IL-17, IFN-γ, and TNF-α) and anti-inflammatory cytokines (IL-4, IL-10, and IL-13) were measured. Groups were tested for differences in single parameters, pro-:anti-inflammatory cytokine ratios, and differences in multivariate patterns.

RESULTS

There were no significant associations between serum levels of vitamin D and any of the self-reported symptoms studied. However, serum levels of certain pro-inflammatory cytokines were significantly higher in subjects with musculoskeletal pain (IL-8, P=0.008), sleep disorders (IFN-γ, P=0.02), and PMS (IL-8 and TNF-α, P=0.009 and 0.002, respectively) compared to subjects who reported no symptoms. The pro-:anti-inflammatory cytokine ratios showed pro-inflammatory cytokine dominance in subjects with self-reported symptoms, particularly in the groups with deficient levels of vitamin D. However, the multivariate cytokine-pattern analysis was significantly different between PMS groups only.

CONCLUSION

These data point to a possible role of pro-inflammatory cytokines as a contributing factor in self-reported symptoms related to musculoskeletal pain, sleep disorders, and PMS.

Association between levels of vitamin D and inflammatory markers in healthy women

Background

No one can deny that the biological importance of vitamin D is much beyond its classical role in bone metabolism. Several recent publications have highlighted its potential role in the functioning of the immune system. The overall objective of this study was to look into possible correlations between levels of vitamin D and inflammatory markers in sera of healthy adult women. These markers included proinflammatory cytokines (interleukin [IL]-1β, IL-6, IL-8, IL-17, interferon [IFN]-γ, and tumor necrosis factor [TNF]-α), anti-inflammatory cytokines (IL-4, IL-10, and IL-13), as well as C-reactive protein (CRP) as a general indicator of inflammation.

Methods

Venous blood samples were collected from 118 healthy adult women and serum levels of vitamin D, CRP, proinflammatory cytokines (IL-1β, IL-6, IL-8, IL-17, IFN-γ, and TNF-α), and anti-inflammatory cytokines (IL-4, IL-10, and IL-13) were measured.

Results

There were no significant direct correlations between serum levels of vitamin D and any of the inflammatory markers measured. However, subjects with deficient levels of vitamin D and high CRP produced significantly higher levels of the proinflammatory cytokines (TNF-α and IL-8) as compared to subjects with low CRP levels with nondeficient and deficient levels of vitamin D. Further, the anti-inflammatory/proinflammatory ratios suggest a role of vitamin D in maintaining an anti-inflammatory environment at low levels of CRP, an association that is weaker at high CRP levels in subjects with subclinical inflammatory situations.

Conclusion

These data point to a possible role of vitamin D as a contributing factor in balancing cytokines toward an anti-inflammatory role in inflammatory situations.

Vitamin D status among indigenous Mayan (Kekchi) and Afro-Caribe (Garifuna) adolescents from Guatemala: a comparative description between two ethnic groups residing on the Rio Dulce at the Caribbean coast in Izabal Province, Guatemala

OBJECTIVE

To assess vitamin D status and the influence of risk factors such as skin pigmentation and time spent outdoors on hypovitaminosis D among Guatemalan Kekchi and Garifuna adolescents.

DESIGN

Cross-sectional study, with convenient sampling design. Blood samples, anthropometric and behavioural data were all collected during the dry season. Serum 25-hydroxyvitamin D (25(OH)D) concentrations were measured by RIA.

SETTING

Communities of Rio Dulce and Livingston, Izabal Province, Caribbean coast of Guatemala, with latitude and longitude of 15°49'N and 88°45'W for Livingston and 15°46'N and 88°49'W for Rio Dulce, respectively.

SUBJECTS

Eighty-six adolescents, divided evenly by sex and ethnicity, with mean age of 14 years.

RESULTS

Mean (sd) 25(OH)D value was 27·8 (7·2) ng/ml for the total group, with 25·8 (5·9) and 29·8 (7·9) ng/ml, respectively, in Kekchis and Garifunas (P=0·01). Use of vitamin D supplementation, clothing practices and sun protection were not statistically different between groups. Skin area exposed on the day of data collection ranged from 20·0 % minimum to 49·4 % maximum, with mean (sd) exposure of 32·0 (8.5) %. With univariate regression analysis, age (P=0·034), sex (P=0·044), ethnicity (P=0·010), time spent outdoors (P=0·006) and percentage skin area exposed (P=0·001) were predictive. However, multivariate analysis indicated that only sex (P=0·034) and percentage skin area exposed (P=0·044) remained as predictors of 25(OH)D.

CONCLUSIONS

Despite residing in an optimal geographic location for sunlight exposure, nearly 65 % of study adolescents were either insufficient or deficient in vitamin D. Correction and long-term prevention of this nutritional problem may be instrumental in avoiding adverse effects in adulthood attributed to low 25(OH)D during adolescence.