Venous thromboembolism in psychogeriatric in-patients – A study of risk assessment, incidence, and current prophylaxis prescribing

Background: While venous thromboembolism (VTE) risk assessment and prophylaxis is well established for medical and surgical in-patients, there is a paucity of evidence, and therefore guidelines, in this area for psychogeriatric in-patients. We wished to determine VTE incidence, risk, and use of prophylaxis, in a psychogeriatric in-patient population. Methods: Retrospective audit of consecutive psychogeriatric patients aged 65 years and over admitted to Bankstown Hospital over a 3-year period, 2007–2009. Using an adapted VTE risk scoring system, patients were assigned as low, medium, or high VTE risk. Results: A total of 192 patients were included in the study. Mean age was 79.1 ± 7.0 years. Out of the total, 55.2% of patients had diagnosis of dementia, and 33.3% had depression. Overall, 81.8% (157/192) were assessed as low risk, and 18.2% (35/192) as medium risk. Also, 16.7% (32/192) received VTE prophylaxis. Four new VTE events occurred in medium-risk group, and one in low-risk group (p = 0.004). Overall VTE incidence was 10.5/10,000 patient-days, but 44.2 per 10,000 in medium-risk group. VTE risk score was predictive of VTE events – IRR 6.02 (95% Confidence Intervals (CI) = 1.76–20.7, p = 0.004) for every one-point increment in risk. Depression was associated with significantly higher VTE occurrence (6.3% in those with diagnosis vs. 0.8% without, p = 0.043). Conclusion: Using a VTE risk scoring system adapted for psychogeriatric in-patients, those assessed to be at medium risk had a significantly increased rate of VTE. On this basis, we would recommend VTE prophylaxis be prescribed for psychogeriatric in-patients assessed to be at medium and high level of risk.