VITAMIN D:TO D OR NOT TO D THAT IS THE QUESTION?

Steven Boyages

The University of Sydney

ISE, Corfu, 30th June 2015

Sydney, Australia

Nutrition Related Disorders

MicronutritionUndernutrition PCM

Minerals and VitaminsFolic Acid

Vitamin D deficiencyVitamin A deficiency

Fe deficiencySelenium deficiency

Iodine deficiency

MacronutritionObesity

HyperlipidemiaInsulin Resistance

DiabetesAlcohol

Key questions

1. Are we vitamin D deficient and whose is at risk?

2. Are we over-diagnosing and over-testing?

3. How much vitamin D do we need and how should we supplement?

Vitamin D: Not a vitamin but a steroid hormone

Synthesis and Metabolism of Vitamin D in the Regulation of Calcium, Phosphorus, and Bone Metabolism

Holick M. N Engl J Med 2007;357:266-281

Physiology: skeletal and non skeletal

Health benefits of vitamin D: Low levels of vitamin D linked to

Osteoporosis and osteopenia

Cancer Diabetes Cardiovascular

disease Autoimmune

disease Multiple sclerosis Respiratory Illness Mental Health

Skeletal Non Skeletal

Sources of vitamin D

Factors affecting vitamin D levels

Season Latitude UVR Cloud cover

Age Skin colour Body fatness Fat malabsorption

Geographical Physiological

• Other factors– Sunscreen– Clothing

Causes of vitamin D deficiency Reduced skin synthesis Decreased bioavailability

Malabsorption Obesity

Increased catabolism Decreased synthesis eg liver failure Increased renal loss Decreased production of 1,25 OH vitamin D Heritable disorders Acquired disorders eg hyperthyroidism,

hyperparathyroidism, tumour induced osteomalacia, granulomatous disorders

Adequate vitamin D statusVitamin D (nmol/L*)Conventional guidelines

Newer recommendations+

Severe Deficiency <12.5

Moderate deficiency 12.5-25

Mild deficiency 25-50 <50

Insufficiency 50-75

Sufficiency >50 >75

*2.5 nmol/L = 1 ng/ml

+Bischoff Ferrari, AJCN 2006

Australian StudiesNo. of subjects

Latitude (0S)

Mean 25(OH)D

Prevalence (%) Ref.

<28 nmol/L

<50 nmol/L

Overall

VIC 861 38 - 7.2 30.0 Pasco 2001

SE QLD 414 28 69.1 8.0 23.4 McGrath 2001

Winter

SE QLD 28 - 40.5 McGrath 2001

VIC 861 38 59.1 11.3 43.2 Pasco 2001

VIC 287 38 17.6 60.3 Pasco 2004

TAS 404 43 36.2 ~7.4 50.7 Van der Mei 2007

QLD/VIC/TAS

1669 28-43 67.0/75.5/ 51.1

7.1/7.9/ 13.0

40.5/37.4/ 67.3

Van der Mei 2007 b

(pooled analysis)

4697

31131 25(OH)D assays1 July 2008 and 30 July

2010

Primary test, complete data available for gender, age, patient setting, date of test, postcode**, known breast cancer case, 25(OH)D ≤400 nmol/L

Sample type

10839 13979

Diagnostic referralOutpatientPrivate outpatientEmergency

InpatientPrivate hospital patientPublic hospital patientPrivate patient

29516

24819

Yes

680618012Female

Male

62016251Summer

Winter 612

16245

Autumn Spring

1615

QC sampleResearchMiscellaneousUnknown

* *Matched to ARIA, SEIFA, Latitude, Longitude

Mean 25(OH)D by gender

Janu

ary

Febr

uary

Mar

chApr

ilMay

June Ju

ly

Augus

tSe

pt

Octob

er

Nove.

..

Dece.

..40.0

45.0

50.0

55.0

60.0

65.0

70.0

75.0 74.0

45.1

65.5

43.2

MaleFe-male

45% re-duction

by June

P<.001

37% reductio

n by June

Mean 25(OH)D by patient setting

Janu

ary

Febr

uary

Mar

chAp

rilMay

June Ju

ly

Augu

stSe

pt

Octob

er

Nove.

..

Dece.

..

Tota

l40.0

45.0

50.0

55.0

60.0

65.0

70.0 70.2

44.9

63.4

42.9

Ambulatory subject

Inpatient

P<.001

Mean 25(OH)D by gender and patient setting

Supporting Women with Breast Cancer Today and Every Day

Janu

ary

Febr

uary

Mar

chApr

ilMay

June Ju

ly

Augus

tSe

pt

Octob

er

Novem

ber

Decem

ber

40.0

45.0

50.0

55.0

60.0

65.0

70.0

75.0

80.0 79.1

48.6

60.4

42.6

Ambulatory MaleAmbulatory FemaleInpatient MaleInpatient Female

Mean 25(OH)D by age group

January

Febr...

Marc

hApril

May

June

July

August

Sept

Oct

Nove...

Dece...

40.0

45.0

50.0

55.0

60.0

65.0

70.0

75.0

80.0

*77.0

65.6

40.7

*61.2

<2020-3940-5960-79≥80

*P<.001

Mean 25(OH)D by remoteness

Maj

or citi

es

Inne

r Reg

iona

l

Outer

Reg

iona

l

Remot

e Au

stra

lia

Very

Rem

ote

Aust

ralia

01020304050607080

50

*71*66

Ambulatory MaleAmbulatory FemaleInpatient maleInpatient Female

*P<.05

Frequency of repeated testing

Bilinski & Boyages BMJ Open 2013;3: e002955

Requests per 100000 for FBC, bone densitometry and vitamin D

Bilinski & Boyages BMJ Open 2013;3: e002955

Results

Bilinski & Boyages MJA 197 (2) · 16 July 2012

Google trends for vitamin D

04/15/2023

©2011 Healthcare Information and Management Systems Society

24

Google Analytics-Google Trends

04/15/2023

©2011 Healthcare Information and Management Systems Society

25

Vitamin D and its musical impact

What was the cause of Mozart’s death?

Preventing over diagnosis

Vitamin D Test Medicare Benefit ($m) per annum: Australia

1994 1999 2004 2009 20140

20,000,000

40,000,000

60,000,000

80,000,000

100,000,000

120,000,000

140,000,000

160,000,000

Medicare Benefit ($m)

Year

$ m

illion

Vitamin D intake recommendations

*Recommendations based on maintaining serum vitamin D > 75 nmol/L (30ng/ml)

Recognition that individuals who are obese or on certain medications be give 2-3 times more vitamin D

40 IU = 1 µg

Age NHMRC IOM US Endo Society*

0-1 200 400 1000

1-18 200 600 1000

19-49 200 600 1500-2000

50-69 400 600 1500-2000

70 and over

600 800 1500-2000

Health Implications

Public health messages required to address high prevalence of vitamin D deficiency

Australians are not adequately supplementing - suitable guidelines are required

Implications regarding frequency and timing of testing

Fortification of food may be a better approach

Acknowledgements Australia

CJ Eastman JP Halpern John K Collins Li Mu

China Indonesia The Netherlands

Hemmo Drexhage USA, Atlanta

GF Maberly Italy, Pisa

Alessandro Antonelli