Professor Adrian R Martineau shares his opinions about how NICE public health guidance can improve access to vitamin D supplements among people at risk of profound deficiency
Read this article to learn more about:
- the problems associated with profound vitamin D deficiency
- the groups of people that are at high risk of profound vitamin D deficiency
- when to prescribe, or recommend over-the-counter, vitamin D supplements.
Vitamin D is a fat-soluble micronutrient that is essential for human health. The two physiologically relevant forms are vitamin D2 (ergocalciferol) and vitamin D3 (cholecalciferol). Vitamin D2 is the plant/fungal form of the vitamin and it can be ingested in supplements or by eating certain types of mushrooms. Vitamin D3 is synthesised in the human skin in response to ultraviolet B radiation from the sun. It may also be ingested from a limited number of foods (primarily oily fish such as salmon, mackerel, and sardines) or by taking supplements.1
Both types of vitamin D are processed in the liver to form the major circulating metabolite, 25–hydroxyvitamin D (25[OH]D)—the concentration of which indicates vitamin D status.
The circulating metabolite 25(OH)D is further hydroxylated to form the active metabolite and steroid hormone 1,25–dihydroxyvitamin D (1,25[OH]2 D); 1,25[OH]2 D binds to the vitamin D receptor to regulate a host of biological functions, including maintenance of serum calcium concentrations, bone mineralisation, muscle strength, and the innate immune response (see Figure 1, below).
|Box 1: NICE Accreditation Mark|
NICE Public Health guidance 56 on Vitamin D: increasing supplement use among at-risk groups has been awarded the NICE Accreditation Mark.
Profound vitamin D deficiency therefore causes problems with bone mineralisation (resulting in rickets, osteomalacia, and osteopenia-induced fractures), calcium homeostasis (hypocalcaemia, which may precipitate seizures), muscle function (cardiomyopathy and falls) and increased susceptibility to infections (tuberculosis and upper respiratory infections).
This article discusses the main recommendations for healthcare practitioners in NICE Public Health (PH) guidance 56 on Vitamin D: increasing supplement use among at-risk groups2 (see Box 1, above).
Defining vitamin D deficiency
There is considerable controversy regarding the threshold for the serum concentration of 25(OH)D that indicates inadequate vitamin D status. In the UK, the Scientific Advisory Committee on Nutrition (SACN) defines vitamin D deficiency as serum 25(OH)D concentrations less than 25 nmol/L.3 Internationally, concentrations of 25(OH)D less than 50 nmol/L are widely agreed to denote vitamin D deficiency.
Many experts in the field suggest that 25(OH)D concentrations greater than 75 nmol/L are required for optimum human health. In view of this, 25(OH)D concentrations within the range of 50–74 nmol/L are commonly categorised as denoting a state of vitamin D insufficiency.1 Because current guidance in NICE PH56 (see text below) refers to the SACN position statement on vitamin D, further comments in this article will be confined to patients with serum concentrations of 25(OH)D less than 25 nmol/L, who will be referred to as having 'profound vitamin D deficiency'.2,3
Profound vitamin D deficiency and at-risk groups
Data from the UK National Diet and Nutrition Survey indicate that around 1 in 5 adults and 1 in 6 children may have profound vitamin D deficiency.4
The following groups are at a particularly high risk of vitamin D deficiency in the UK:2
- infants and children aged <5 years
- pregnant and breastfeeding women, particularly teenagers and young women
- older people aged >65 years
- people who have no or limited exposure to the sun of sufficient intensity to induce cutaneous vitamin D synthesis, including people who:
- cover their skin for cultural reasons
- are confined indoors
- live in Scotland and Northern England2
- individuals who have darker skin (e.g. people of African, African-Caribbean, or South Asian ethnic origin).
Profound vitamin D deficiency is responsible for a significant burden of morbidity and mortality for people within these groups, and many of them may not be aware that they are at a high risk. Data from the NHS showed that 160 cases of symptomatic vitamin D deficiency presented to health services in the West of Scotland between 2002 and 20085 with complications of profound vitamin D deficiency including rickets, hypocalcaemic seizures, and cardiomyopathy (a condition that may be fatal6).
In order to address the problem of profound vitamin D deficiency in the UK, SACN recommended that people belonging to the risk groups listed above should take a vitamin D supplement sufficient to meet their Reference Nutrient Intake (RNI) (see Table 1, below).3
However, these recommendations have not been widely implemented; therefore, NICE was asked by the Department of Health to develop guidance to support an increase in supplement use among at-risk groups to prevent profound vitamin D deficiency.
|7 months to 3 years||7||7|
|Lactation, 0–4 months||-||10|
|Lactation, >4 months||-||10|
|Note: The above RNIs apply to healthy populations. Those at risk of inadequate sunlight exposure may require supplementation. Scientific Advisory Committee on Nutrition. Update on Vitamin D: Position statement by the Scientific Advisory Committee on Nutrition. London: TSO, 2007. Reproduced with permission.|
NICE PH56 on Vitamin D: increasing supplement use among at-risk groups was issued in November 2014.2 The eleven recommendations are listed in Table 2 (below). The guidance is for healthcare professionals as well as other organisations/bodies who have an important role to play in addressing the issue of vitamin D deficiency.
|1||Increase access to vitamin D supplements|
|2||Clarify existing guidance|
|3||Develop national activities to increase awareness about vitamin D|
|4||Ensure a consistent multi-agency approach|
|5||Increase local availability of vitamin D supplements for at-risk groups|
|6||Improve access to Healthy Start supplements|
|7||Only test vitamin D status if someone has symptoms of deficiency or is at very high risk|
|8||Ensure health professionals recommend vitamin D supplements|
|9||Raise awareness among health, social care and other relevant practitioners of the importance of vitamin D|
|10||Raise awareness of the importance of vitamin D supplements among the local population|
|11||Monitor and evaluate the provision and uptake of vitamin D supplements|
NICE (2014) Vitamin D: increasing supplement use among at-risk groups. Public health guidance 56.
Health professionals do not generally need to test vitamin D status in asymptomatic people in at-risk groups before advising them to take a vitamin D supplement. This recommendation is based on the fact that the dose of vitamin D in the RNI for adults at risk of deficiency (400 IU or 10 μg/day) is 25-fold lower than the tolerable upper intake level for vitamin D (10,000 IU or 250 μg/day).3,7 So it is safe to take a vitamin D supplement containing the RNI irrespective of baseline vitamin D status.
The NICE PH56 guidance includes a health economic analysis demonstrating that the costs of testing for vitamin D status and offering targeted supplementation to those found to have profound deficiency is less cost effective than offering universal supplementation.8
If patients have symptoms, signs, or abnormal laboratory results suggesting vitamin D deficiency (e.g. myalgia, proximal myopathy, clinical or radiological features of rickets or osteomalacia, hypocalcaemia, or secondary hyperparathyroidism) then their vitamin D status should be tested, irrespective of whether or not they belong to an at-risk group.2 People found to have profound vitamin D deficiency on testing may require higher treatment doses of vitamin D: the nature of such dosing regimens is beyond the scope of this document. More information on the management of profound vitamin D deficiency can be found in the review article co-authored by Professor Simon Pearce and Dr Tim Cheetham.9
Issuing, recommending, and recording supplements
Health professionals may prescribe a licensed vitamin D supplement, or recommend an over-the-counter supplement containing the RNI, at their discretion.2
Health professionals should recommend and record vitamin D supplement use among at-risk groups whenever possible.2 This could take place at routine appointments and health checks including, for example:2
- registration appointments with new patients
- antenatal and postnatal appointments
- developmental checks for infants and children
- health visitor appointments
- NHS Health Checks
- appointments made for vaccinations.
Computerised prompts on vitamin D should be integrated into healthcare and social care systems to support health professionals in making this a routine activity.2
NICE PH56 also recommends that developers of standardised electronic and handheld maternity notes and developers of personal child health records ('the red book') should add specific questions about the use of vitamin D supplements.2
Raising awareness—healthcare, social care, and other practitioners
Healthcare professionals should help to increase awareness of the importance of vitamin D. Training and continuing professional development activities represent good opportunities to do this. Healthcare, social care and other relevant practitioners in contact with at-risk groups need to become aware of local policies and procedures in relation to vitamin D; healthcare professionals should recommend Healthy Start vitamins to eligible women (for eligibility criteria, see the guidance glossary) or let women (eligible or not) know where they can buy them.2
Challenges to implementation
People in at-risk groups may be reluctant to take a vitamin D supplement owing to the costs involved, and the difficulty in obtaining a supplement containing the RNI. NICE PH56 seeks to address these issues by recommending that the Department of Health should work with the manufacturers of vitamin D supplements to ensure that all products containing the RNI for vitamin D are made more widely available and at an affordable price.2 In response to this recommendation, the Department of Health has announced that it will change its regulations so that from 2015 community pharmacies can sell the low-cost Healthy Start vitamins (which contain vitamin D) to women and children who do not qualify to receive them for free.10
The guidance also recommends that local authorities should consider providing free vitamin D supplements for at-risk groups.2 NICE is currently reviewing the cost effectiveness of moving the Healthy Start vitamins from a targeted to a universal scheme. NICE is expected to report to the Chief Medical Officer (CMO) about this issue during 2015.
People in at-risk groups may be reluctant to take a vitamin D supplement without having a test to determine their vitamin D status beforehand. If this situation arises, healthcare professionals may wish to reassure these patients about the safety of taking a supplement containing the RNI, and to highlight the potential health benefits of doing so, in terms of preventing rickets, osteomalacia, falls, and fractures.
The role of sunlight in preventing vitamin D deficiency may seem to conflict with sun protection messages. Draft NICE guidance (GID-PHG77) on communicating the benefits and risks of sunlight to people's health and wellbeing is available (see here) and publication is expected in July 2015. This guidance is intended to complement NICE PH56 on vitamin D2 and NICE Ph22 on Skin cancer prevention: information, resources and environmental change.11
A useful source of patient information,Vitamin D deficiency including osteomalacia and rickets, can be found here.
The following developments are expected in the short- to medium-term:
- The Scientific Advisory Committee on Nutrition is due to release an updated Position Statement on vitamin D in the spring of 2015, at which stage the RNI for the UK population may be revised
- NICE is undertaking a report for the Chief Medical Officer on the cost effectiveness of moving Healthy Start vitamins from a targeted to a universal scheme. This report from NICE will be forwarded to the CMO in 2015
- Worldwide, several large-scale randomised controlled trials are being conducted to establish whether the correction of lesser degrees of vitamin D deficiency is associated with health and mortality benefits. Findings are expected to be reported from 2017 onwards.
Profound vitamin D deficiency is particularly common among: infants and children aged less than 5 years, pregnant and breastfeeding women, people aged over 65 years, people who have limited exposure to sunshine, and people with darker skin. People in these groups should take a daily supplement containing the RNI for vitamin D.
GP commissioning messages
- NICE Public Health guidance 56 on vitamin D supplementation for at-risk groups has not been widely and consistently implemented
- The lead responsibility for implementing this guidance lies with public health departments now based in local authorities
- CCGs may, however, face marked funding pressures if vitamin D supplements are issued through NHS prescriptions, because the relevant population groups (e.g. all people aged over 65 years and those aged under 5 years) are immense, often representing 20%–30% of the total local population
- CCGs should, therefore, liaise with local departments of public health as to how this guidance is to be implemented, and how the cost of vitamin D supplements are to be borne (whether by departments of public health, the CCG, or the patient)
- Once the approach to implementation has been agreed, CCG formularies should identify cost-effective preparations of vitamin D containing the correct dosages for prescription or purchase.
CCG=clinical commissioning group
Health professionals do not need to routinely test vitamin D status in asymptomatic people in at-risk groups before advising them to take a vitamin D supplement
- may prescribe a licensed vitamin D supplement, or recommend an overthe- counter supplement containing the reference nutrient intake, at their discretion
- should recommend and record vitamin D supplement use among at-risk groups; computerised prompts on vitamin D should be integrated into healthcare and social care systems to support health professionals in making this a routine activity
- should help to develop better awareness of the importance of vitamin D
Specific questions about the use of vitamin D supplements should be added to maternity notes and personal child health records (the 'red book').
- Holick M. Vitamin D deficiency. N Eng J Med 2007; 357 (3): 266–281.
- NICE. Vitamin D: increasing supplement use among at-risk groups. Public health guidance 56. NICE, 2014. Available at: www.nice.org.uk/guidance/PH56
- Scientific Advisory Committee on Nutrition.Update on Vitamin D: Position statement by the Scientific Advisory Committee on Nutrition. London: TSO, 2007. Available at: www.gov. uk/government/uploads/system/uploads/ attachment_data/file/339349/SACN_Update_on_Vitamin_D_2007.pdf
- Public Health England and the Food Standards Agency. National diet and nutrition survey: results from years 1, 2, 3 and 4 (combined) of the rolling programme (2008/2009–2011/2012). London: PHE, 2014. Available at: www.gov. uk/government/uploads/system/uploads/ attachment_data/file/310995/NDNS_Y1_to_4_UK_report.pdf
- Ahmed S, Franey C, McDevitt H et al. Recent trends and clinical features of childhood vitamin D deficiency presenting to a children's hospital in Glasgow. Arch Dis Child 2011; 96: 694–696.
- Maiya S, Sullivan I, Allgrove J et al. Hypocalcaemia and vitamin D deficiency: an important, but preventable, cause of lifethreatening infant heart failure. Heart 2008; 94: 581–584.
- Hathcock J, Shao A, Vieth R, Heaney R. Risk assessment for vitamin D. Am J Clin Nutr 2007;85: 6–18.
- NICE. An economic evaluation of interventions to improve the uptake of vitamin D supplements in England and Wales. NICE, 2014. Available at: bit.ly/nice-increasing-supplement-use
- Pearce S, Cheetham T. Diagnosis and management of vitamin D deficiency. BMJ 2010;340: b5664.
- The Healthy Start Vitamins (Charging) Regulations 2014. SI 2014 No. 3099. The Stationery Office, 2014. Available at: www. legislation.gov.uk/uksi/2014/3099/contents/ made
- NICE. Skin cancer prevention: information, resources and environmental changes. Public Health guidance 32. NICE, 2011. Available at:www.nice.org.uk/guidance/ph32