维生素D水平与重症患者新发房颤有相关性

　　新发房颤（NOAF）是ICU患者常见的并发症，且与患者的发病率及死亡率密切相关。众多研究证实系统性炎症在促使NOAF的发生中起重要作用。同时，近期研究表明维生素D具有潜在的抗炎作用，且ICU患者维生素D水平普遍较低。

　　为了探讨维生素D水平与外科重症患者NOAF之间的相关性，美国宾夕法尼亚州立大学医学院、麻省总医院回顾性入组500例外科ICU患者，检测其入住ICU24小时之内的25-羟维生素（25-OHD）水平及72小时内持续心房颤动的发生情况。

　　结果发现，25-OHD水平每增加一个单位，NOAF的发生风险下降15%，且低25-OHD水平（＜20ng/ml）患者发生NOAF可能性是高水平患者（≥20ng/mL）的将近4倍（OR=3.59）。

　　因此，该研究证实了外科重症患者的维生素D水平可作为NOAF发生风险的一个可靠的预测因素。

JPEN J Parenter Enteral Nutr. 2017;41(2):279-280.

Vitamin D status is associated with new-onset atrial fibrillation in critically ill surgical patients.

Joseph S. Needleman; D. Dante Yeh; Donna M. Belcher; Sadeq A. Quraishi.

Penn State College of Medicine, Hershey, Pennsylvania, USA; Massachusetts General Hospital, Boston, Massachusetts, USA.

Purpose: New-onset atrial fibrillation (NOAF) is a common complication in the intensive care unit (ICU), which is associated with increased morbidity and mortality. Although there are several treatment options once the arrhythmia develops, to date, strategies to prevent the onset of NOAF are limited. A growing body of evidence suggests that systemic inflammation plays an important role in the pathogenesis of NOAF; however, the use of traditional anti-inflammatory agents has been shown to be ineffective or is contraindicated in critically ill patients. Recent data suggest that vitamin D has potent anti-inflammatory properties and that low vitamin D status is very common in ICU patients. Therefore, our goal was to investigate whether admission vitamin D status is associated with NOAF in critically ill surgical patients.

Methods: We performed a retrospective analysis of data from a prospective, observational study of nutrition status in critically ill surgical patients. Patients were recruited from 2 surgical ICUs of a single teaching hospital in Boston, Massachusetts. All patients had 25-hydroxyvitamin D (25OHD) levels measured within 24 hours of ICU admission. NOAF was defined as the occurrence of sustained atrial fibrillation within 72 hours of ICU admission, which required medical intervention (either pharmacological or cardioversion). To limit confounding, we excluded patients with a known history of arrhythmias or those who were found to be in atrial fibrillation at the time of ICU admission. To investigate the association of 25OHD levels with NOAF, we first performed a logistic regression analysis, controlling for body mass index (BMI), Acute Physiology and Chronic Health Evaluation (APACHE) II score, and the type of surgical patient (ie, general, thoracic, vascular, emergency/trauma, and neurosurgery), while considering vitamin D status as a continuous variable. Since vitamin D adequacy has been defined conservatively as 25OHD levels ≥20 ng/mL, we therefore repeated the regression analysis, while considering vitamin D status as a dichotomous variable (ie, 25OHD levels <20 ng/mL vs ≥20 ng/mL).

Results: In total, 500 patients comprised the analytic cohort. Mean (SD) 25OHD level was 18 (8), ng/mL and 36 patients (7.2%) developed NOAF. In our primary analysis, when vitamin D status was considered as a continuous variable, regression analysis demonstrated that each unit increment in 25OHD level was associated with a 15% reduced risk of NOAF (odds ratio [OR], 0.85; 95% confidence interval [CI], 0.78–0.93). In our secondary analysis, when vitamin D status was considered as a dichotomous variable, regression analysis demonstrated that patients with 25OHD levels <20 ng/mL were almost 4 times more likely to develop NOAF (OR, 3.59; 95% CI, 1.01–12.70) compared with those with levels ≥20 ng/mL. In these models, both BMI and APACHE II scores were also independently associated with NOAF. Compared with general surgery patients, thoracic (OR, 5.02; 95% CI, 1.63–15.39) and vascular surgery (OR, 3.75; 95% CI, 1.18–11.94) patients were more likely to develop NOAF.

Conclusions: Our results suggest that vitamin D status may be a modifiable risk factor for NOAF in critically ill surgical patients. Future randomized controlled trials are needed to determine whether vitamin D supplementation and/or optimization early in the course of critical illness can reduce the risk of NOAF and its related complications.

Financial support: National Institutes of Health, Grants L30 TR001257 and T32 GM007592.

DOI: 10.1177/0148607116686023