Is prolonged immobilization a risk factor for symptomatic venous thromboembolism in elderly bedridden patients?

Abstract

Prolonged immobilization and advanced age are considered to be important risk factors for venous thromboembolism (VTE). Nevertheless, the need for VTE prophylaxis in long-term bedridden patients is not known. To assess whether very prolonged immobilization (i.e. over three months) carries an increased risk for clinically apparent VTE, we performed a historical-cohort study of nursing home residents during a ten-year period. Data concerning patient's mobility and incidence of overt deep vein thrombosis or pulmonary embolism were registered. The mean resident age was 85+/-8.4 years. Eighteen mobile and eight immobile patients were diagnosed with clinically significant thromboembolic events, during 1137 and 573 patient-years of follow up, respectively. The incidence of venous thromboembolic events was similar in both chronically immobilized and mobile patient groups, 13.9 and 15.8 per thousand patient years, respectively (p=0.77). The rate ratio for having a VTE event in the immobilized patient group as compared with the mobile group was 0.88 (95% Confidence Interval (CI) 0.33 to 2.13). When taking into account baseline characteristics, risk factors and death rates by various causes, no differences were found between the two groups. In conclusion, chronically immobile bedridden patients are no more prone to clinically overt venous thromboembolic events than institutionalized mobile patients. Until further studies are performed concerning the impact of very prolonged immobilization on the risk of VTE, there is no evidence to support primary prevention after the first three months of immobilization. Evidence for efficacy or cost effectiveness beyond this early period is not available.

A prospective observational study of a cohort of outpatients with an acute medical event and reduced mobility: incidence of symptomatic thromboembolism and description of thromboprophylaxis practices

“…Furthermore, the analysis was restricted to the first 3 weeks only. However, it should be noted that: (i) the median duration of reduced mobility was 7 days; (ii) in all recent thromboprophylaxis trials, the primary efficacy end-point was assessed between 2 and 3 weeks after inclusion [4][5][6]; (iii) thromboprophylaxis in medical patients is recommended for up to 2 weeks [7]; and (iv) the 3-week incidence rate of venous thromboembolism reported in our study is similar to the 1-year incidence rate reported in a recent study in nursing home residents [28]. Another limitation is the fact that approximately 20% of symptomatic events were not confirmed using an objective test.…”

Incidence of venous thromboembolism in care homes: a prospective cohort study

“…[24][25][26][27] Gomes and colleagues found an incidence of 1.30 events per 100 PY, 24 Gatt et al found an incidence of 1.4 to 1.6 per 100 PY, 25 and Leibson and colleagues found an incidence of 1.2 to 1.5 per 100 PY. 26 These studies, however, relied on nursing home administrative data and diagnostic codes, and were, therefore, subject to diagnostic uncertainty and misclassification.…”

Risk of Venous Thromboembolism in Patients Nursed at Home or in Long-Term Care Residential Facilities

“…We do not even know the level of risk for VTE in these patients or the real risk factors. Advanced age and limited mobility alone are insufficient reasons for prescribing prophylaxis [4] but it is important to identify among elderly chronic patients with reduced mobility those with additional factors that raise their risk profile for VTE.…”