the role of vitamin in heart health and cardiovascular...

The role of Vitamin in heart health

Dr Sohail Mushtaq s.mushtaq@chester.ac.uk @SohailMushtaq

and cardiovascular disease prevention

Vitamin D • majority of vit D synthesised in the skin from action

of UVB radiation (290-320nm) •  synthesis during summer months must provide for

vit D needs during winter •  in UK little/no synthesis occurs in skin between Oct

and March –  light with correct wavelength does not reach Earth surface

ergocalciferol

Alexandra Schmid, and Barbara Walther Adv Nutr 2013;4:453-462

©2013 by American Society for Nutrition

cholecalciferol

Food sources contributing to dietary vitamin D in UK

meat + meat products 30%

fat spreads 19%

fish + fish products 17%

cereals 13%

eggs + egg dishes 13%

milk + milk products 5%

National Diet and Nutrition Survey. Rolling Programme (2008/2009 – 2011/12) : Age group: 19-64

Vitamin D deficiency •  vitamin D deficiency is becoming more common

in developed countries •  in UK, the prevalence of vitamin D deficiency in

adults is around 40% in winter (NDNS 2008-2011)

Vitamin D deficiency

Pearce SH ,Cheetham TD. Diagnosis and management of vitamin D deficiency. BMJ 2010

Vitamin D deficiency •  in adults may be due to:

–  extensive covering with clothing –  skin colour –  failure to spend time outdoors –  use of anti-UVB sunscreens results in decreased skin

synthesis of vitamin D –  inadequate diet –  link with obesity?

•  in adults over 65, an inadequate diet, reduced gut absorption and reduced mobility increase risk

Preventing vitamin D deficiency

DOHrecommenda-ons:•  Allinfantsandchildrenunder5yearsshouldtakesupplements–atleast280IU(7µg)daily

•  Allpregnant/breasIeedingwomenshouldtake400IU(10µg)vitaminDsupplementsdaily

• People aged 65 years and over should also take a daily supplement containing 400IU(10µg)of vitamin D

Gropper et al. (2013)

Vitamin D receptor (VDR)

Vitamin D receptors are widely dispersed

Vitamin D and CVD risk

OBSERVATIONAL STUDIES: Forest plot of all meta-analyses stratified by measured biomarker with relative risk as type of metric.

Theodoratou E et al. BMJ 2014;348:bmj.g2035

©2014 by British Medical Journal Publishing Group

Ku et al. World J Cardiol 2013; 5(9): 337-346

STROKE: Forest plots including on-trial only results from the RECORD.

John A Ford et al. Am J Clin Nutr 2014;100:746-755 ©2014 by American Society for Nutrition

MI: Forest plots including on-trial only results from the RECORD.

John A Ford et al. Am J Clin Nutr 2014;100:746-755 ©2014 by American Society for Nutrition

HEART FAILURE: Forest plots including on-trial only results from the RECORD. Squares or diamonds indicate the point estimate of the study or overall effect.

John A Ford et al. Am J Clin Nutr 2014;100:746-755 ©2014 by American Society for Nutrition

Pfeiffer et al. J Clin Endocrinol Metab. 2001 Apr;86(4):1633-7.

Mechanisms of action

Potential mechanisms

Ku et al. World J Cardiol 2013; 5(9): 337-346

Conclusions and future perspectives •  observational studies report an inverse association between serum

25(OH)D concentration and CVD risk

•  meta-analyses of RCTs investigating the effect of vitamin D supplementation on CVD risk, including hypertension and stroke are inconsistent

•  many studies in relation to vitamin D use CVD risk as a secondary outcome there are few long term RCTs, supplementing with vitamin D alone

–  VITAL (vit D/omega3), n=20,000 healthy participants, 2,000IU vitamin D, 5yrs

•  further research to elucidate potential mechanisms is required

•  current evidence does not support supplementation of vitamin D to reduce CVD risk

•  no basis yet to make recommendations for the optimum supplementation based on anything other than musculoskeletal health (eg. CVD risk)