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Vitamin D deficiency: Pragmatic suggestions for prevention and treatment.

Byline: Sanjay Kalra

Abstract

Vitamin D deficiency is endemic to South Asia, and is associated with varied biochemical and clinical presentations. Health care professionals of all specialties need to ensure optimal Vitamin D level of all persons, irrespective of age or gender, to prevent the many complications that are associated with vitamin D deficiency. These pragmatic recommendations aim to support health care professionals in assessing, preventing and treating vitamin D deficiency, in a rational manner.

Keywords: Osteomalacia, Rickets, Vitamin D.

Physiology

Vitamin D, also known as cholecalciferol, the sunshine vitamin, or anti-rachitic vitamin, is actually a hormone. Cholecalciferol is synthesized in the skin by exposure to ultraviolet light, and then hydroxylated at 25 and 1 carbon positions, in the liver and kidneys, to produce 25- hydroxy vitamin D, (25(OH)D) and 1,25 dihydroxy vitamin D (1,25(OH)2D) respectively.1,2 Small amounts of vitamin D may be derived from dietary sources such as fish oil.

Vitamin D acts on vitamin D receptors (VDR) in target cells, where it forms heterodimers with the retinoid X receptor (RXR), which activate vitamin D target genes. Vitamin D's main function is to regulate calcium and phosphate metabolism, in the intestine, bone and kidneys. In coordination with parathyroid hormone and fibroblast growth factor 23, Vitamin D increases calcium absorption from the intestine, enhances calcium reabsorption from the kidney, and promotes bone formation. Apart from its skeletal effects, vitamin D is also thought to fulfil many extra skeletal roles. These include facilitation of insulin secretion, innate immunity, cardiovascular health and anti-neoplastic defense.1 Research is ongoing in these fields.

Normal Values

Vitamin D (25(OH) D) levels between 20 and 40ng/ml (50 and 100 nmol/l) are considered optimal for the majority of people.3 These levels are associated with minimal adverse clinical effects such as fractures and falls. Vitamin D levels of above 30ng/ml are optimal for patients with osteoporosis, or older adults (>50 years) at high risk of osteoporosis.

Vitamin D in South Asia

As sunlight and the skin are the main sources of vitamin D, alterations in sunlight exposure of skin may modify vitamin D levels. Darker skinned individuals, and those whose skin is not exposed to sunlight because of clothing, sunscreen use, or lack of outdoor activities, may have lower vitamin D levels. Ultraviolet irradiation is reduced during winter, in temperate latitudes (as opposed to tropical or equatorial latitudes), and by the presence of air pollution. All these factors contribute to vitamin D deficiency.3,4

Numerous studies on high prevalence of hypovitaminosis D in both rural and urban areas in adults, the elderly, antenatal women, children, infants and neonates have shown that vitamin D levels of neonates correlate with their mothers.5-18 The common clinical presentations of vitamin D deficiency are listed in Table-1.

Table-1: Clinical presentation of vitamin d deficiency.

###Infants###Children###Adults

Symptoms###Difficult breathing,###Repeated infection,###Bone pains, muscle

###irritability###bone pains, difficulty pain, muscle

###in squatting/###weakness, difficulty in

###standing/walking###squatting/standing

###/walking, frequent falls

Signs###Seizures, Tetany###Hypotonia, delayed###Wadding gait,

###Stridor###dentition, enamel###anterior tibial

###hypoplasia, dental###weakness, Rib cage

###caries, wrist widening tenderness, fractures

###Dilated###Rachitic rosary, Knock Pelvic deformities,

###cardiomyopathy,###knees, Bow legs.###Kyphoscoliosis

###Craniotabes, open

###anterior fontanelle,

###frontoparietal bossing

It is difficult to achieve currently recommended vitamin D levels with sunlight exposure alone. Sunlight exposure of 15-30% of total body surface area, for 30 minutes, between 11 am and 3 pm, during summer, (when the sun is at its zenith) is able to achieve an increase of 4 ng/ml in children.

Vitamin D Screening

Universal screening for vitamin D levels is not recommended. However, screening with 25 (OH) vitamin D should be considered in persons with

- Symptoms/signs suggestive of

* osteomalacia

* osteoporosis

* musculoskeletal disease

* high risk factor for vitamin D deficiency

* inflammatory bowel disease

* bariatric surgery

* chronic kidney disease

* drug use

- antiepileptic

- antitubercular

- glucocorticoids

- antiretroviral

- ketoconazole

Extra indications of measurement of 25 (OH) D in children include

Late onset hypocalcaemic seizures

Dilated cardiomyopathy

Rickets

Cancer

Organ transplant recipients

Chronic inflammatory rheumatic disease

Juvenile idiopathic arthritis

Ankylosing spondylitis

1, 25 (OH) 2 D testing is indicated in:

- chronic kidney disease

- phosphate-losing bone disease

- oncogenic osteomalacia

- Vitamin D- resistant rickets

- Chronic granulomatous disease

* Sarcoidosis

* Lymphoma

Supplementation

The recommended vitamin D intake for South Asians is 600-1000 IU/day for healthy adults aged less than 50 years, and 800-2000 IU/day for high risk individuals and older adults. The upper range of these doses should be preferred in South Asians. Doses of up to 4000 IU/day do not require monitoring, while doses of 10000 IU/day are not associated with toxicity.

Treatment

Vitamin D deficiency is treated or prevented with cholecalciferol, which is available in drop, capsule, sachet, suspension, and injectable form. Cholecalciferol is also included in many fixed dose combinations of calcium and vitamins. Various studies have shown the benefits of supplementing Vitamin D in Indian populations.19-26

Four options are available for use in adults (Table-2).

Table-2: Treatment options with cholecalciferol in adults.

Regimen###Description###Indications/Comments

Weekly###60000 IU weekly x 8 weeks,###Asymptomatic persons with

###followed by 60000 IU/month###very low vitamin D (< 10

###life###ng/ml)

###Metabolic bone disease

###(rickets, osteomalacia)

###Double dose may be used in

###obesity, malabsorption,

###concomitant anti-tubercular

###and anticonvulsant therapy

Monthly###60000-120000 IU per month,###Apparently healthy subjects

###life long###60000 IU in summer and

###120000 IU in winter

Daily###1000-2000IU/day, with or###Mild vitamin D deficiency

###without calcium, life long###Elderly

###Pregnancy/ lactation

###Prevention

###Maintenance therapy

Parenteral mega dose###300000-600000 IU per 6###Limited oral absorption

###months###Poor compliance

###Not recommended as first

###line (significant variation in

###absorption: risk of

###hypercalcemia

Table-3: Treatment options with cholecalciferol in special situations.

Regimen###Description###Indications/Comments

ASYMPTOMATIC

Infants###400 IU/day###Begin within first few days of

###birth: continue through infancy

Children###600-1000 IU/day or 60000 IU###Continue through childhood

###once in 2-3 months

Adolescents###1000IU/day in all; 2000 IU/day###Continue through adolescence

###in obese

SYMPTOMATIC

Infants###1000-2000 IU/day x 8-12 weeks###No role for weekly regimen

Children###2000-4000 IU/day x8-12 weeks###Alternative 60000 IU every 14

###days: x 8-12 weeks

Adolescents###4000-6000 IU/day x 8-12###150000 IU stat; repeat after 6

###weeks###weeks if necessary

###Alternative 300000 IU stat;

###repeat after 6 week if necessary

###60000 IU/ week x 6-8 weeks

Pregnancy 2nd and###1000 IU/ day for all; 2000 IU/day Weekly or monthly doses are

3rd trimesters; lactation###in high risk/deficient women###not recommended

Chronic kidney disease/renal 60000 IU weekly x 8 weeks,###Monitor serum calcium every 3

transplant: Documented###followed by 60000 IU/ month###months in renal disease; at

vitamin D deficiency###least once in liver disease

Chronic kidney disease-###Maintenance: 60000 IU/

deficiency not documented;###month or 2000 IU daily

non-deficient renal

transplant recipients;

chronic liver disease

Table-3 lists regimes and doses for infants, children, adolescents, antenatal women, and special populations such as chronic kidney disease and chronic liver disease. Adequate calcium intake must be ensured (30-75 mg/kg/day in children).

Summary

This communication describes the etiopathogenesis, symptoms and signs of Vitamin D deficiency. Through the pragmatic suggestions listed herein, we aim to support health care professionals in assessing, preventing and treating vitamin D deficiency, in a rational manner.

References

1. Mithal A, Wahl DA, Bonjour JP, Burckhardt P, Dawson-Hughes B, Eisman JA, et al. IOF Committee of Scientific Advisors (CSA) Nutrition Working Group. Global vitamin D status and determinants of hypovitaminosis D. Osteoporos Int. 2009; 20: 1807-20.

2. Wahl DA, Cooper C, Ebeling PR, Eggersdorfer M, Hilger J, Hoffmann K. A global representation of vitamin D status in healthy populations. Arch Osteoporos. 2012; 7: 155-72.

3. Dawson- Hughes B, Mithal A, Bonjour JP, Boonen S, Burckhardt P, Fuliehan GEH. IOF position statement: Vitamin D recommendations for older adults. Osteoporos Int 2010; 21: 1151-4.

4. Holick MF, Binkley NC, Bischoff Ferrari HA, Gordon CM, Hanley DA, Heaney RP et al. Evaluation, treatment, and prevention of vitamin deficiency: An endocrine society clinical practice guideline. J Clin Endocrinol Metab 2011; 96: 1911-30.

5. Goswami R, Gupta N, Goswami D, Marwaha RK, Tandon N, Kochupillai N. Prevalence and significance of low 25-hydroxyvitamin D concentrations in healthy subjects in Delhi. Am J Clin Nutr 2000; 72: 472-5.

6. Tandon N, Marwaha RK, Kalra S, Gupta N, Dudha A, Kochupillai N. Bone mineral parameters in healthy young Indian adults with optimal vitamin D availability. Natl Med J India 2003; 16: 298-302.

7. Beloyartseva M, Mithal A, Kaur P, Kalra S, Baruah MP, Mukhopadhyay S, et al. Widespread vitamin D deficiency among Indian health care professionals. Arch Osteoporos. 2012; 7: 187-92.

8. Harinarayan CV, Ramalakshmi T, Prasad UV, Sudhakar D. Vitamin D status in Andhra Pradesh: a population based study. Indian J Med Res. 2008; 127: 211-8.

9. Ramakrishnan S, Bhansali A, Bhadada SK, Sharma R, Walia R, Ravikiran M, et.al. Vitamin D status and its seasonal variability in healthy young adults in an Asian Indian urban population. Endocr Pract. 2011; 17: 185-91.

10. Marwaha RK, Tandon N, Garg MK, Kanwar R, Narang A, Sastry A et.al. Bone health in healthy Indian population aged 50 years and above. Osteoporos Int. 2011; 22: 2829-36.

11. Shetty S, Kapoor N, Nair D, Asha HS, Prabu S, Thomas N,et.al. Osteoporosis in healthy South Indian males and the influence of life style factors and vitamin d status on bone mineral density. J Osteoporosis. 2014; 72: 32 -38.

12. Shivane VK, Sarathi V, Bandgar T, Menon P, Shah NS. High prevalence of hypovitaminosis D in young healthy adults from the western part of India. Postgrad Med J. 2011; 87: 514-8.

13. Basu S, Gupta R, Mitra M, Ghosh A. Prevalence of vitamin d deficiency in a pediatric hospital of eastern India. Indian J Clin Biochem. 2015; 30: 167-73.

14. Marwaha RK, Tandon N, Chopra S, Agarwal N, Garg MK, Sharma B et.al. Vitamin D status in pregnant Indian women across trimesters and different seasons and its correlation with neonatal serum 25-hydroxyvitamin D levels. Br J Nutr. 2011; 106: 1383-9.

15. Bhalala U, Desai M, Parekh P, Mokal R, Chheda B. Subclinical hypovitaminosis D among exclusively breastfed young infants. Indian Pediatr. 2007; 44: 897-901.

16. 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 India. Am J ClinNutr 2005; 81: 1060-4.

17. Sahu M, Bhatia V, Aggarwal A, Rawat V, Saxena P, Pandey A et.al. Vitamin D deficiency in rural girls and pregnant women despite abundant sunshine in northern India. Clin Endocrinol (Oxf). 2009; 70: 680-4.

18. Ekbote VH, Khadilkar AV, Chiplonkar SA, Khadilkar VV. Determinants of bone mineral content and bone area in Indian preschool children. J Bone Miner Metab. 2011; 29: 334-41.

19. Goswami R, Gupta N, Ray D, Singh N, Tomar N. Pattern of 25-hydroxy vitamin D response at short (2 month) and long (1 year) interval after 8 weeks of oral supplementation with cholecalciferol in Asian Indians with chronic hypovitaminosis D. Br J Nutr. 2008; 100: 526-9.

20. Malhotra N, Mithal A, Gupta SK, Shukla M, Godbole MM. Effect of vitamin D supplementation on bone health parameters of healthy young Indian women. Arch Osteoporosis. 2009; 4: 47-53.

21. Ekbote VH, Khadilkar AV, Chiplonkar SA, Hanumante NM, Khadilkar VV, Mughal MZ. A pilot randomized controlled trial of oral calcium and vitamin D supplementation using fortified laddoos in underprivileged Indian toddlers. Eur J Clin Nutr. 2011; 65: 440-6.

22. Khadgawat R, Marwaha RK, Garg MK, Ramot R, Oberoi AK, Sreenivas V, Gahlot M, Mehan N, Mathur P, Gupta N. Impact of vitamin D fortified milk supplementation on vitamin D status of healthy school children aged 10-14 years. Osteoporos Int. 2013; 24: 2335-43.

23. Kalra P, Das V, Agarwal A, Kumar M, Ramesh V, Bhatia E et.al. Effect of vitamin D supplementation during pregnancy on neonatal mineral homeostasis and anthropometry of the newborn and infant. Br J Nutr. 2012; 108: 1052-8.

24. Kumar GT, Sachdev HS, Chellani H, Rehman AM, Singh V, Arora H et.al. Effect of weekly vitamin D supplements on mortality, morbidity, and growth of low birth weight term infants in India up to age 6 months: randomised controlled trial. BMJ. 2011; 342: d2975.

25. Garg MK, Marwaha RK, Khadgawat R, Ramot R, Obroi AK, Mehan N et.al. Efficacy of vitamin D loading doses on serum 25-hydroxy vitamin D levels in school going adolescents: an open label non-randomized prospective trial. J Pediatr Endocrinol Metab. 2013; 26: 515-23.

26. Agarwal N, Mithal A, Dhingra V, Kaur P, Godbole MM, Shukla M. Effect of two different doses of oral cholecalciferol supplementation on serum 25-hydroxy-vitamin D levels in healthy Indian postmenopausal women: A randomized controlled trial. Indian J Endocrinol Metab. 2013; 17: 883-9.
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Publication:Journal of Pakistan Medical Association
Geographic Code:9INDI
Date:Jul 31, 2017
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