Is this D vitamin to worry about? Vitamin D insufficiency in an inpatient sample.

OBJECTIVE: The aim of the present study was to investigate the relationship between reduced serum vitamin D levels and psychiatric illness.

METHOD: This study was an audit of serum 25-hydroxyvitamin D (25-OHD) levels measured routinely in a sample of 53 inpatients in a private psychiatric clinic. These levels were compared with those of controls without psychiatric illness.

RESULTS: The median levels of serum 25-OHD were 43.0 nmol L(-1) (range 20-102 nmol L(-1)) in the patient population, 46.0 nmol L(-1) (range 20-102 nmol L(-1)) in female patients (n =33) and 41.5 nmol L(-1) (range 22-97 nmol L(-1)) in male patients (n =20). The proportion of vitamin D insufficiency (serum 25-OHD < or =50 nmol L(-1)) in this patient population was 58%. Furthermore, 11% had moderate deficiency (serum 25-OHD < or =25 nmol L(-1)). There was a 29% difference between mean levels in the patient population and control sample (geometric mean age- and season-adjusted levels: 46.4 nmol L(-1) (95% confidence interval (CI) =38.6-54.9 nmol L(-1)) vs 65.3 nmol L(-1) (95%CI =63.2-67.4 nmol L(-1)), p <0 .001).

CONCLUSION: Low levels of serum 25-OHD were found in this patient population. These data add to the literature suggesting an association between vitamin D insufficiency and psychiatric illness, and suggest that routine monitoring of vitamin D levels may be of benefit given the high yield of clinically relevant findings.