Vitamin D status of adolescent inpatients in a secure psychiatric hospital

Abstract

Objective:

The objective of the study was to use routinely collected data on vitamin D levels of adolescents detained in a secure psychiatric hospital to see if this at-risk group for vitamin D deficiency do in fact have low vitamin D levels.

Methods:

Vitamin D blood levels were collated from clinical records of inpatients admitted to Bluebird House, a medium secure adolescent unit, since 2012. Corresponding data were gathered to include gender, ethnic status and age. Blood levels were assessed on admission to the unit and after treatment with vitamin D supplementation, if indicated.

Results:

Only 3 out of the 35 patients (8.6%) had adequate vitamin D levels (serum 25-hydroxyvitamin D [25-OHD] > 50 nmol/l). A total of 23 patients (65.7%) had levels consistent with deficiency (25-OHD < 30 nmol/l) with the remaining 9 patients (25.7%) showing levels indicating possible deficiency (25-OHD 30–50 nmol/l.

Conclusions:

Vitamin D levels were low in our sample of young people admitted to a secure psychiatric hospital. This is the first published study of vitamin D levels in a secure adolescent psychiatric hospital. The results point to the need for routine prescription of vitamin D to adolescents held in secure conditions such as hospitals, secure children’s homes and youth offender institutes.

Introduction

Vitamin D is essential for skeletal growth and bone health, and deficiency is common in the UK and the rest of Europe [González-Gross et al. 2012]. The term vitamin D is used for a range of compounds which possess the property of preventing or curing rickets. These include ergocalciferol (vitamin D2), colecalciferol (vitamin D3) and calcitriol (1,25-dihydroxycholecalciferol).

The average UK diet contains little vitamin D and the most important source is synthesized in the skin following exposure to sunlight [NICE, 2014]. Low vitamin D levels can result in rickets in children [Pearce and Cheetham, 2010], as well as osteomalacia. It has been associated with long-term conditions such as osteoporosis. Other health problems such as cardiovascular disease, type 2 diabetes and autoimmune conditions have been linked with vitamin D insufficiency [Pearce and Cheetham, 2010]. There is a growing literature linking vitamin D to brain development and growth [Kesby et al. 2011], but the impact of deficiency on mental health is not clear.

There is no recommended dietary intake for vitamin D in the UK for people aged 4 and 65 years as it is thought that sunlight acting on the skin will provide sufficient vitamin D for this age group. However, it is recognized that certain groups are at high risk of developing vitamin D deficiency. These groups are those who either do not expose any of their skin to sunlight for cultural or religious reasons and those who live in settings with little exposure to sunlight. Ethnic minorities with darker skins are also at relatively higher risk of developing deficiency when living in the UK [NICE, 2014]. Other risk factors are obesity, malabsorption, renal and liver disease, and prescription of anticonvulsants. Vitamin D levels vary significantly throughout the year and it is important to factor seasonality into the data [Sachs et al. 2013]. Vitamin D status is most reliably determined by assay of serum 25-hydroxyvitamin D (25-OHD).

Since the Chief Medical Officer in the UK wrote guidance on vitamin D supplementation in high-risk groups [McGee and Shaw, 2013], we have measured blood vitamin D levels on all new inpatients at Bluebird House and offered supplements when they are measured as being low. Bluebird House is a secure psychiatric hospital for adolescents [Hill et al. 2014], and although we make every effort to give our patients exposure to sunlight they are likely to have much less exposure to sun than the average adolescent. Most of our patients are admitted from other secure institutions such as secure hospitals, secure children’s homes and youth offender institutions where exposure to natural light is likely to be limited. Previous studies [Murie et al. 2012] have indicated that prisoners and adults in secure hospitals have generally low vitamin D levels. A study of blood levels of vitamin D in recently admitted psychiatric inpatients demonstrated low levels [Mast et al. 2010]. There are no published studies of vitamin D levels in a secure adolescent hospital. It is particularly important that vitamin D status is adequate during childhood and adolescence because of its role in bone development and therefore growth [Harel et al. 2013].

In this study of vitamin D levels in our patients we used data that we had collected in routine clinical work to find out if vitamin D levels are low in the potentially at-risk group of adolescents detained in a secure hospital.

Methods

We collected data from our clinical records on vitamin D levels for our discharged and current patients since 2012. We also collected data on gender, ethnicity and age for each young person.

Results

Since 2012 the vitamin D levels of 35 (26 female, 9 male) adolescent inpatients aged between 13 years and 17 years (mean 15.7 years) were measured. The Osteoporosis Society 2103 guidelines for 25-OHD levels are: < 30 nmol/l – consistent with deficiency, 30–50 nmol/l – may indicate deficiency and > 50 nmol/l – adequate level [Francis et al. 2013].

Serum levels of 25-OHD ranged between 11 nmol/l and 71 nmol/l at the time of admission with a mean of 30.5 nmol/l. Accounting for seasonality the mean is 29.7 nmol/l indicating that the average vitamin D level is consistent with deficiency. A total of 22 (6 male, 16 female) out of the 35 subjects were in the deficient range measuring between 12 nmol/l and 29 nmol/l. A total of 10 out of the patients (3 male and 7 female) were in the possible deficiency range measuring between 30 nmol/l and 50 nmol/l. Only three subjects, who were all female, were not deficient with scores ranging between 53 nmol/l and 74 nmol/l. These values all take into account seasonality using the online calculator (kri.washington.edu/calculator) [Sachs et al. 2013].

The mean of the admission 25-OHD levels, taking into account seasonality, was 30.1 nmol/l, for the female patients, and 28.7 nmol/l, for the male patients. The mean 25-OHD level of the white British patients was not significantly different from the eight patients from different ethnic backgrounds (two Asian and six black patients).

Of the 32 patients with 25-OHD levels in the deficient or possibly deficient range 23 agreed to being prescribed replacement therapy (Calcichew). After treatment the mean 25-OHD level had increased from 29.7 nmol/l to 45.9 nmol/l. In two out of the three patients that were initially identified with adequate vitamin D levels follow-up data collection revealed that these levels had both fallen to indicate possible deficiency and deficiency, respectively.

Three patients following the trial of Calcichew were identified to have a lower vitamin D level.

Discussion

The vast majority of teenage patients admitted to Bluebird House have low vitamin D levels on admission. This is possibly because our patients have mainly been admitted from other secure institutions where access to natural light is likely to be limited. This is the first study demonstrating low vitamin D levels in an adolescent population in secure conditions. However, it is in line with previous studies of adults in secure conditions [Murie et al. 2012; Every-Palmer and Souter, 2015]. Low levels of exposure to sunlight may be a contributing factor but other possible factors are poor nutritional intake and the impact of psychotropic medication. Some antipsychotic medications are known to interfere with vitamin D synthesis. Much higher blood concentrations of 25-OHD have been found in community samples in the UK with a mean 64.3 nmol/l for a large Northern Ireland adolescent sample [Hill et al. 2008]. Only 32% of children attending a paediatric orthopaedic clinic in Southampton had 25-OHD concentrations less than 50 nmol/l [Davies et al. 2011]. In a US sample of community patients 42% had a 25-OHD level below 50 nmol/l [Gordon et al. 2004]. Median 25-OHD levels in a European sample were 57.1 nmol/l [Gonzalez-Gross et al. 2012].

In stark contrast only 3 out of our 35 patients had levels above 50 nmol/l suggesting that adolescents in secure psychiatric care are at very high risk of vitamin deficiency. For two out of these three patients this adequate level was not sustained highlighting the significant impact that secure care can have on vitamin D synthesis.

Our results point to the need for routine monitoring of vitamin D levels for adolescents held in secure placements. The NICE guidelines recommend this for those at high risk of vitamin D deficiency [NICE, 2014]. In the UK secure placements are found in secure hospitals, secure children’s homes, secure training centres and youth offender institutes. Given how prevalent the low levels of vitamin D appear to be it may be of benefit to routinely prescribe vitamin D for young people held in secure conditions rather than only prescribe after the result of a blood test. Although a small psychiatric hospital is well placed to measure blood levels in all patients this is far less likely to be the case in a youth offender institution with 400 boys. Simple vitamin D deficiency can be prevented by taking an oral supplement of ergocalciferol or colecalciferol. The product prescribed at Bluebird House (Calcichew) is a chewable tablet containing calcium and colecalciferol.

There may be merit in the routine prescription of a multivitamin tablet containing vitamin D and fish oils to young people held in secure conditions given the evidence from a randomized controlled trial in a youth offender institute that it can improve behaviour and reduce violent incidents [Gesch et al. 2002]. Although vitamin D levels respond well to oral supplements we have found a significant proportion of patients did not want to take them and this is seen in the data with some of the vitamin D levels falling despite treatment.

Attention to diet in secure institutions and exposure to sunlight remains extremely important. It is vital that the multidisciplinary team include staff responsible for planning meals provided to children in care. Furthermore, it is important to further this holistic view by focusing on how the design in secure facilities can play a key role in establishing outdoor spaces within the facility. Staff must be aware of how important access to these outdoor areas is for adolescents; even more so if there is evidence of vitamin D deficiency.

Strengths and limitations

This observational study is the first to provide data of vitamin D status in an adolescent secure population. Whilst the sample size of the study is small there is some variation of ethnicity representing a typical admission cohort to a secure unit in this area of England. The study has not addressed the effect that prescribed medication may have on vitamin D levels.