Risk factors associated with deep venous thrombosis in patients with different bed-rest durations: A...

Deep vein thrombosis represents a threat to public health and a heavy economic burden to society, and often occurs as a complication or cause of death in bedridden patients. How to prevent deep vein thrombosis is a general concern in clinical practice. However, it remains uncertain whether the risk factors for deep vein thrombosis would be affected by different bed-rest durations. Solving this issue will be invaluable for the provision of more rational medical care to prevent deep vein thrombosis.

To explore whether risk factors for deep vein thrombosis are affected by bed-rest durations and to identify different risk factors in groups with different bed-rest durations.

A retrospective multicenter case-control study.

This multicenter study was conducted in wards with high rates of bed rest in 25 general hospitals in China. Participants were bedridden patients from these wards.

Bedridden patients were identified from the research database of bedridden patients' major immobility complications. These data were collected from prospective descriptive studies by a standardized web-based online case report form. Cases were defined as bedridden patients who suffered deep vein thrombosis during hospitalization (n=186). Each case was matched with three controls, bedridden patients who did not suffer deep vein thrombosis in the same center with the same bed-rest duration (n=558). Descriptive statistics, univariate analysis, and multivariate conditional logistic regression models were employed.

Among 23,985 patients, the overall incidence of deep vein thrombosis during hospitalization was 1.0%. Multivariate analysis showed that for patients with bed-rest duration of 4 weeks or less, older age (odds ratio [OR] =1.027, 95% confidence interval [CI] 1.013-1.041) and being in a surgical department (OR=2.527, 95% CI 1.541-4.144) were significantly associated with increased risk of deep vein thrombosis. Female sex (OR=4.270, 95% CI 1.227-14.862), smoking (OR=10.860, 95% CI 2.130-55.370), and special treatment (OR=3.455, 95% CI 1.006-11.869) were independent factors predicting deep vein thrombosis for patients with bed-rest durations from 5 to 8 weeks. For those with bed-rest durations from 9 to 13 weeks, Charlson Comorbidity Index (OR=1.612, 95% CI 1.090-2.385) was the only independent risk factor for deep vein thrombosis.

Risk factors for deep vein thrombosis varied among patients with different bed-rest durations. This finding is helpful for nurses to increase their awareness of prevention of deep vein thrombosis in patients with different bed-rest durations, and lays a more solid foundation for clinical decision making.