Vitamin D status of psychiatric inpatients in New Zealand’s Waikato region

David B Menkes,Stephen A Du Toit,Kaye Lancaster,Reginald W Marsh,Peter Dean,Michael Grant

doi:10.1186/1471-244x-12-68

David B Menkes, Stephen A Du Toit + Show 4 more

Open Access

https://doi.org/10.1186/1471-244x-12-68

Copy DOI

Abstract

BackgroundVitamin D deficiency is widespread in New Zealand, confers multiple health risks, and may be particularly common among people with psychiatric illness. We studied vitamin D status in an unselected sample of adult psychiatric inpatients in Hamilton (latitude 37.5 S) during late winter.MethodsWe recruited 102 consenting subjects and measured 25-hydroxy vitamin D3 levels in venous blood using a competitive electrochemiluminescence immunoassay. In addition to descriptive statistics, we used one-sample t-tests to determine the extent to which ethnic and diagnostic subgroups fell below the vitamin D deficiency threshold of 50 nM.Results75 subjects (74%) had vitamin D levels <50 nM and thus had at least mild deficiency, while 19 (19%) were severely deficient with levels <25 nM. Rates of deficiency were comparable for men and women; only the former showed a correlation of vitamin D levels with age (r = 0.45, p < 0.01). Maori participants constituted half the sample (n = 51) and were more likely to be deficient than their European counterparts (p = 0.04). Vitamin D also varied by diagnosis, with schizophrenia associated with markedly lower levels than mania and depression (p < 0.001).ConclusionsVitamin D deficiency is prevalent in the psychiatric inpatient setting in New Zealand and may be relevant to poor physical health outcomes, notably among Maori and those with schizophrenia. These findings support proposals to provide vitamin D supplementation, particularly during the winter months.

Highlights

Vitamin D deficiency is widespread in New Zealand, confers multiple health risks, and may be common among people with psychiatric illness
Our results indicate a substantial frequency of vitamin D deficiency in a New Zealand inpatient psychiatric population, and accord with evidence of widespread deficiency in the country generally [7,8,9], and in psychiatric samples overseas [13,14,15]
Previous studies performed in nearby Auckland [17,18] found vitamin D deficiency to be more frequent in women than men; in our sample there was only a slight, insignificant excess of women with severe deficiency

Summary

Introduction

Vitamin D deficiency is widespread in New Zealand, confers multiple health risks, and may be common among people with psychiatric illness. We studied vitamin D status in an unselected sample of adult psychiatric inpatients in Hamilton (latitude 37.5 S) during late winter. Vitamin D plays a central role in the regulation of calcium status and is essential for bone health [1]. Evidence has accumulated that vitamin D has other important physiological roles, and is relevant to a variety of clinical conditions, including mental illness. Vitamin D appears to influence mood symptoms, based on epidemiological [3] and clinical trial evidence [4]. Because bone disease is clearly associated with blood levels

Objectives

Methods

Results

Discussion

Conclusion