RESEARCH ARTICLE               ISSN: 2467-9151             OPEN ACCESS

Prevalence of vitamin D deficiency among adult population of Western Region of Nepal

 

Mahesh Prakash Bhatta1*, Bhupendra Raj Pandey1, Khusi Man Gurung1, Rasmita Nakarmi1, Kshamata

Gurung1, Lal Bahadur Gurung1, Srijana Rana Magar1

1United Reference Laboratory, Pokhara, Nepal

 

ABSTRACT

Background: Vitamin D deficiency is major public health threat throughout the world, particularly among people living in low income nations like Nepal. It is a steroid hormone, vital for asserting calcium homeostasis and optimizing bone health. Decreased concentrations of vitamin D result in changes in calcium and phosphorus homeostasis, secondary hyperparathyroidism, bone loss, osteoporosis, and an increase in fracture risk. Vitamin D deficiency is determined as a level of 25-hydroxy vitamin D reduces to less than 25ng per milliliter. The aim of this study was to review the vitamin D condition and population-based occurrence of vitamin D deficiency, in western region of Nepal, in adult. A secondary aim was to examine determinants of vitamin D deficiency and its occurrence by gender, ethnicity and other demographic factors within this population.

Methods: A cross sectional laboratory based experimental study was done in total of 2158 subjects (19-60yrs) who visited United Reference Laboratory from 20th July, 2014 to 17th December, 2015. Data were collected on subjects from that days visit, including age, sex, self -declared ethnicity and place where they live. Determination of vitamin D was performed in serum of subjects in fully automated Cobas e411 analyzer. Data analysis was done by SPSS version 20.0 software.

Results: Out of 2158 subjects (692 male, 1466 female), 1590 (73.68%) had vitamin D deficiency, whereas only 568 (26.32%) had optimum level of vitamin D. Females were more deficient than male by 5.29% (P=0.016). Deficiency of vitamin D was found significant in all season, but deficiency percentage increases during winter (81.62%) and spring (88.82%) as compared to autumn (57.07%) and summer (70.39%) (P=0.00). It was found that Brahmins were significantly more deficient of vitamin D as compared to other ethnic group (P=0.00).

Conclusion: There is high prevalence of vitamin D deficiency in 73.68% of working adult population of Western Region of Nepal. This finding evinces that vitamin D deficiency is significantly associated with gender, season, and ethnicity variable.

Keywords: Cobas e411, Ethnicity, Gender, Season, 25-hydroxy vitamin D [25(OH)D]

BACKGROUND

Vitamin D denotes cholecalciferol, produced by the action of ultraviolet light with a wavelength of 290–320 nm on 7- dehydrocholesterol in the skin of humans. Once made in the skin or ingested, vitamin D is transported to the liver from kidney where it is hydroxylated into 25- hydroxy vitamin, which is the major circulating form of vitamin D [1].

Vitamin D is a steroid hormone with pleiotropic effects on calcium and phosphorus metabolism and the immune system[2].

*Correspondence: Mahesh Prakash Bhatta

1United Reference Laboratory, Pokhara, Nepal

E-mail: bhattamahesho4@gmail.com

Tel: 00977 – 98 04 112854

Vitamin D is essential for maintaining calcium homeostasis and bone health. Low concentrations of vitamin D lead to alterations in calcium and phosphorous homeostasis, secondary hyperparathyroidism, bone loss, osteoporosis, and an increase in fracture risk [3]. The standard method of assessing vitamin D status is by measuring serum concentration of the major circulating metabolite of vitamin D, 25-hydroxy vitamin D [25(OH)D] [3].

Low levels of 25-hydroxy vitamin D [25(OH)D], the principal circulating storage form of vitamin D, are present in as many as one third to one half of otherwise healthy middle-aged to elderly adults [4]. The high prevalence of low vitamin D status is assumed to result from inadequate sun exposure [5]. Increasing urbanization that results in poor outdoor activity and greater pollution, coupled with skin pigment, may further compound this problem [6]. Although there is no consensus on optimal levels of 25- hydroxy vitamin D as measured in serum, vitamin D deficiency is defined by most experts as a 25-hydroxy vitamin D level of less than 20 ng per millilitre [7].

Over the past two decades, several national population- based epidemiological   studies in the United States, Canada, United Kingdom, and   New Zealand     have reported that 52–77% of the populations had 25(OH)D levels <75 nmol/l and 18% to 36% had levels <50 nmol/l [8]. In Australia, vitamin D deficiency has been identified as a problem in certain subgroups, including elderly people, dark skinned and veiled women and those living in residential care [8].

The aim of this study was to assess the vitamin D status and population-based prevalence of vitamin D deficiency in western region of Nepal. This is the first epidemiological study to have evaluated the vitamin D status in western region of Nepal. A secondary aim was to examine determinants of vitamin D deficiency and

compare the prevalence rates by gender, ethnic, and other demographic factors within this population.

METHODOLOGY Study population

We studied 2158 patients (19-60 years) who visited

United Reference Laboratory from 20th July, 2014 to 17th December, 2015. Exclusion criteria included a chronic illness and use of medications known to affect bone metabolism. All participants provided oral informed consent. The Committee on Clinical Investigation, URL approved the protocol.

Data collection

Data were collected on patients from that day’s visit, including age, sex, self-declared ethnicity and place where they live.

Laboratory measurements

One blood sample (5 mL) was obtained in gel tube for each subject and serum was separated by the use of centrifuge to estimate vitamin D [25(OH)D]. Vitamin D estimation was performed in the United Reference Laboratory (URL) using kits provided by the Roche. Serum 25(OH)D levels were measured by automated electrochemiluminescence (ECLIA, Cobas e411, Roche diagnostics, Germany). On the basis of serum 25(OH)D concentrations, patients were divided into 3 diagnostic categories, as rounded to the nearest integer. Subjects with

25(OH)D level concentration less than 10ng/ml were classified as severe deficiency, 10 to 24ng/ml as mild- moderate deficiency and greater than or equal to 25ng/ml as optimum level [9].

Statistical analysis

Data analysis was done by using Statistical Package for the Social Sciences (SPSS) Version 20.0. Mean value and standard deviation were represented as mean +S.D. Data with P value <0.05 were considered to be significant.

RESULTS

The present article is based on laboratory based cross sectional study of 2158 samples of adult (19-60 years). Population aged less than 19 years and greater than 60 years were not included in this study, only working population were included. This report is focused on the

distribution and determination of vitamin D status in the

60%

50%

40%

30%

20%

10%

0%

17%

19%

53%

57%

Male

Female

30%

25%

adult population of western region of Nepal.

Status of vitamin D on the basis of level and gender

severe deficiency

Mild-Moderate Optimum Level deficiency

Out of total 2158 samples collected from participants visiting united reference laboratory, 394 subjects (18.26%) were under severe deficiency whereas nearly greater than half, (55.42%) 1196 accounted for mild to moderate deficiency, and only remaining (26.32%) 568 have

optimum levels of vitamin D as shown in Fig 1.

Fig 2: Status of Vitamin D among Male and Female

Table 1: Mean value and standard deviation of

Vitamin D

 

Total             Male         Female

 

25(OH)D

 

Trends

Mean     S.D.   Mean   S.D.   Mean   S.D.

 

 

 

 

26%

18%

 

 

 

56%

severe deficiency

 

Mild-Moderate deficiency

 

Optimum Level

Severe deficient

6.49     2.49     6.83     2.02     6.35     2.21

 

 

 

 

 

 

Fig 1: Vitamin D status of adult population

 

 

In the context of male and female, out of 692 male, 119 (17.20%) were in severe deficient phases, 366 (52.89%) were in mild to moderate deficient phases and remaining

207 (29.91%) had optimum levels of vitamin D. Similarly out of 1466 female, 275 (18.76%) were severely deficient,

830 (56.62%) were mild to moderately deficient and remaining 361 (24.62%) had optimum levels of vitamin D. Comparatively, in the overall perspective, female showed more Vitamin D deficiency than male as shown in Fig 2 and Table 1.

S.D. = Standard Deviation

 

 

Mild- Moderate deficient 17.20 4.16         17.29   3.97         17.16   4.24
Optimum levels 33.19 8.08         33.06   7.99     33.6           8.14

 

Status of vitamin D on the basis of season

 

 

Seasonal wise study reveals, 10.30% of population were severely deficient, 60.08% of population were in mild to moderate deficient phase and 29.62% of population had optimum level of vitamin D in summer. Similarly 5.40% of population were severely   deficient, 51.65% of population were in mild to moderate deficient phase and

42.93% of people had optimum level in autumn, whereas in winter 28.88% of population were severely deficient,

53.33% of population were in mild to moderate deficient phase and 17.79% had optimum levels. Likewise, 34.18%

 

 

 

of population were severely   deficient, 54.63% of population were in mild to moderately deficient phase and

11.18% had optimum level of vitamin D in spring (Fig 3). This study utterly indicates most of people were vitamin

D deficient especially during winter (16.19+9.71) and spring (14.68+9.41) as compared to summer (20.93+ 9.61) and autumn (24.4+10.93). Vitamin D is found at optimum level mainly in autumn and in summer. This study elucidates, people are more deficient of vitamin D in

spring and then in winter as a whole.

Severe deficient                   Mild-moderate Deficient

Optimum levels

 

60%

 

40%

 

20%

 

0%

 

 

 

 

Ethnic groups

 

 

 

   
 
 
 
 
 
 
         

 

70%

60%

50%

40%

30%

20%

10%

0%

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Season

 

 

 

Severe

Deficient

 

 

Mild- Moderate deficient

 

Optimum level

Fig 4: Distribution of vitamin D among ethnic group

 

 

DISCUSSION

 

This was cross-sectional laboratory based experimental study, conducted mainly to   determine prevalence of vitamin D deficiency   and compare prevalence rate with gender, season and ethnicity in western region of Nepal. According to this study, the prevalence rate of vitamin D deficiency was 73.68% (1590 out of 2158 subjects) in adult population. This study showed significant deficiency of vitamin D in adult population of Western Region of Nepal. Similar data was presented in the study conducted

by GannagéYared et al., showing 72.8% of population

 

 

Fig. 3: Seasonal wise Vitamin D patterns

 

 

Status of vitamin D on the basis of ethnicity

 

 

The study shows, all ethnic group population were vitamin D deficient, out of which, Brahmins were most deficient, followed by Chhetri, Dalit, Newar, Gurung and other ethnic groups whereas Magar community was least deficient of vitamin D. This study shows, in all ethnic groups vitamin D is significantly deficient, and amongst them, most in Brahmin and least in Magar (Fig 4).

affected by hypovitaminosis D [10].

 

This study elucidated females were significantly more deficient of vitamin D as compared to male (70.08% vs.

75.37%) (P=0.016). This is due to socio economic status

 

as most of male were exposed to external environment that is working outside at sun for long time. Study by Roomi et al. in India also found similar outcome, that is female are significantly more deficient than male [11], which is also

supported by Verdoia et al [12], GannagéYared et al [10],

and also by Bolland et al. [13].

 

Deficiency of vitamin D was found significant in all season, but more deficient during winter (81.62%) and spring (88.82%) as compared to autumn (57.07%) and

 

 

 

summer (70.39%) (P=0.00), which was similar to the findings of van der Mei et al , Goswami et al and Daly et al [14, 8, 15] . Study done in Australian population by Gill et al [16]   and Korean adults by Choi [17] also demonstrated the similar outcome.

In context of ethnicity wise comparison of prevalence rate of vitamin D deficiency, there were still no any data available related to it, but in our study, vitamin D was found significantly more deficient in Brahmin (77.7%) and least in Magar (61.9%) (P=0.00).

 

 

CONCLUSION

 

Our study shows significant deficiency of vitamin D among working population of Western Region of Nepal. The prevalence of insufficiency is significantly more in female population than in male population. It is also observed that vitamin D is significantly less deficient in summer and autumn as compared to winter and spring. It is less deficient in Magar as compared to other ethnic groups. This finding evinces, vitamin D variation is significantly associated with gender, season, and ethnicity variable.

 

 

COMPETING INTERESTS

 

The authors declare that they have no competing interests concerning the work reported in this paper.

 

 

CONTRIBUTIONS

 

MPB, KG, LBG, RN, SRM performed the sample collection, data collection and laboratory experiments. BRP supervised and guided in the research. MPB, KMG performed statistical analysis, conceived part of this study and revised the manuscript. All authors read and approved the final manuscript.

 

 

 

ETHICAL CONSIDERATION

 

This study was approved by Institutional Review

 

Committee of United Reference Laboratory, Pokhara,

Nepal. Informed verbal agreement was taken from patients.

 

 

ACKNOWLEDGEMENTS

 

The study was funded by the United Reference Laboratory (URL), Pokhara, Nepal. We would like to thank Mr. Thakur Prasad Panta, managing director, Mr. Sushil Thapa, advisor, Board of directors as well as the entire team of URL for their unlimited support without which this work would not have been completed.

 

REFERENCES

 

  1. 1.   Munns C, Zacharin MR, Rodda CP, Batch JA. Prevention and treatment of infant and childhood vitamin D deficiency in Australia and New Zealand: a consensus statemen Medical Journal of Australia. 2006;185(5):268.

 

  1. 2.   Hintzpeter B, Scheidt-Nave C, Müller MJ, Schenk L, Mensink G Higher prevalence of vitamin D deficiency is associated with immigrant background among children and adolescents   in   Germany.   The Journal   of nutrition.

2008;138(8):1482-90.

 

 

  1. 3.   Holick MF, Siris ES, Binkley N, Beard MK, Khan A, Katzer JT, et a Prevalence of vitamin D inadequacy among postmenopausal North American women receiving osteoporosis therapy. The Journal of Clinical Endocrinology

& Metabolism. 2005;90(6):3215-24.

 

 

  1. 4.   Gordon CM, DePeter KC, Feldman HA, Grace E, Emans S

 

Prevalence of vitamin D deficiency among healthy adolescents. Archives of pediatrics & adolescent medicine.

2004;158(6):531-7.

 

 

  1. 5.   Binkley N, Novotny R, Krueger D, Kawahara T, Daida YG, Lensmeyer G, et a Low   Vitamin D Status despite Abundant Sun Exposure. The Journal of Clinical Endocrinology & Metabolism. 2007;92(6):2130-5.

 

 

 

  1. 6.   Sachan A, Gupta R, Das V, Agarwal A, Awasthi PK, Bhatia V. High prevalence of vitamin D deficiency among pregnant women and their newborns in northern Ind The American journal of clinical nutrition. 2005;81(5):1060-4.

 

  1. 7.   Holick MF. Vitamin D deficiency. New England Journal of

 

Medicine. 2007;357(3):266-81.

 

 

  1. 8.   Daly RM, Gagnon C, Lu ZX, Magliano DJ, Dunstan DW, Sikaris KA, et a Prevalence of vitamin D deficiency and its determinants in Australian adults aged 25 years and older: a

national, population‐based study. Clinical endocrinology.

2012;77(1):26-35.

 

 

  1. 9.   Pardanani A, Drake MT, Finke C, Lasho TL, Rozell SA, Jimma T, et a Vitamin D insufficiency in myeloproliferative neoplasms and myelodysplastic syndromes: clinical correlates and prognostic studies. American journal of hematology. 2011;86(12):1013-6.
  2. 10. Gannagé‐Yared MH, Chemali R, Yaacoub N, Halaby G.

Hypovitaminosis D in a sunny country: relation to lifestyle

 

and bone markers. Journal of bone and mineral research.

 

2000;15(9):1856-62.

 

 

  1. 11. Roomi MA, Farooq A, Ullah E, Lone Hypovitaminosis D and its association with lifestyle factors. Pakistan journal of medical sciences. 2015;31(5):1236-40.

 

  1. 12. Verdoia M, Schaffer A, Barbieri L, Di Giovine G, Marino P, Suryapranata H, et Impact of gender difference on vitamin D status and its relationship with the extent of coronary artery disease. Nutrition, metabolism, and cardiovascular diseases : NMCD. 2015;25(5):464-70.

 

  1. 13. Bolland MJ, Grey AB, Ames RW, Horne AM, Mason BH,

Wattie DJ, et al. Age‐, gender‐, and weight‐related effects on levels of 25‐hydroxyvitamin D are not mediated by

vitamin   D   binding   protein.   Clinical   endocrinology.

 

2007;67(2):259-64.

 

  1. 14. van der Mei IA, Ponsonby A-L, Engelsen O, Pasco JA, McGrath JJ, Eyles DW, et a The high prevalence of vitamin D insufficiency across Australian populations is only partly explained by season and latitude. Environmental health perspectives. 2007:1132-9.

 

  1. 15. Goswami R, Gupta N, Goswami D, Marwaha RK, Tandon N, Kochupillai Prevalence and significance of low 25- hydroxyvitamin D concentrations in healthy subjects in Delhi.   The   American   journal   of   clinical   nutrition.

2000;72(2):472-5.

 

 

  1. 16. Gill TK, Hill CL, Shanahan EM, Taylor AW, Appleton SL, Grant JF, et a Vitamin D levels in an Australian population. BMC public health. 2014;14(1):1.

 

  1. 17. Choi 25(OH)D status and demographic and lifestyle determinants of 25(OH)D among Korean adults. Asia Pacific journal of clinical nutrition. 2012;21(4):526-35.

 

 

 

 

 

 

Article History:

Received: 25 December, 2015

Accepted: 25 January, 2016

Published online: 15 February, 2016

 

 

 

For Citation:

Bhatta MP et al.: Prevalence of vitamin D deficiency among adult population of Western Region of Nepal. International Journal of Medicine & Biomedical Sciences. 2016; 1(2):7-12