A study has shown that patients with low vitamin D levels in the blood are at increased risk of serious complications or death after surgery, cardiac surgery excluded. For each 5 ng/ml increase of vitamin D in the blood the overall risk of death and complications after surgery decreased seven percent.
A group of researchers wanted to investigate to what extent there is a relationship between vitamin D levels and severe consequences such as serious hospital infections and deaths after surgery. The researchers analyzed data from 3,500 patients who all had undergone surgery in the period 2005-2011, which did not involve the heart, and where simultaneous data on patients' vitamin D levels around the time of surgery from three months before to one month after were available .
Widespread vitamin D deficiency
The majority of patients did not meet the minimum requirement for normal vitamin D levels in the blood which is more than 30 nanograms per milliliter (ng/ml). The average vitamin D level was 23.5 ng/ml - more than 60 percent of the patients had borderline vitamin D deficiency (10 to 30 ng / ml), and nearly 20 percent had an actual vitamin D deficiency (less than 10 ng / ml).
Patients with the lowest vitamin D levels (less than 13 ng/ml) had the highest risk of death or serious complications. Those with higher vitamin D levels (up to 44 ng/ml) had about half the risk as those in the lowest group. There was a linear reduced reduction in serious complications during hospital stay for every 5 ng/ml increase in vitamin D in the blood. The connection to low vitamin D was only statistically significant for cardiovascular complications, although there were "strong trends" for mortality and infections.
Since the study was not designed to determine with sufficient certainty whether there is any causal link between vitamin D and the outcome of surgery, the researchers suggest, therefore, that a larger randomized study is made to assess whether so-called preoperative vitamin D may reduce the risk of serious complications and death after surgery.
Turan A, et al. The Association of Serum Vitamin D Concentration with Serious Complications After Noncardiac Surgery. Anesth Analg, 2014;119(3):603-12