A feasibility study of the CRISP intervention; a cardiovascular risk reduction intervention in patients with an abdominal aortic aneurysm

Background Abdominal aortic aneurysm (AAA) screening/surveillance is implemented widely. Those in AAA-surveillance are at high-risk of cardiovascular-events. We developed an intervention, called CRISP, using intervention-mapping, to reduce cardiovascular-risk in AAA-surveillance. This study tested the CRISP intervention in routine clinical-care. Methods The CRISP intervention, consisting of a nurse-led cardiovascular risk assessment and subsequent lifestyle change support using a self-care workbook and low-intensity nurse input was delivered in two screening/surveillance programmes. Those consenting to take part were followed-up with cardiovascular-assessments. Fidelity of intervention-delivery was assessed quantitatively/qualitatively. Results 40 men (mean age 75 ± 7 years) took part over four months and followed-up for a minimum six months. A sub-group of 25 patients and nine Health Care Professionals (HCPs) were interviewed. The median number of risk-factors that patients chose to focus on was two (range 0 to 4), with physical activity (n=17) being the most popular. Participants who had a ‘red light’ risk factor for stress, low mood, smoking or alcohol intake were offered a referral to appropriate services. Two were offered referral to mental-health services and took it up, three declined referrals to smoking or alcohol support services. The fidelity of intervention-delivery (a score intervention components delivered to each patient based on a score from 0 to 5, with 5 being highest delivery fidelity) was generally low. The highest mean score (on a 0-5 scale) for the nurse assessment was 1.5 for engaging the participant, lowest 0.5 for exploring the importance for selected lifestyle behaviours. In qualitative interviews, the intervention was liked by patients/HCPs. Based on qualitative interviews and observations, the low fidelity of intervention-delivery was due to intervention-training not being detailed. Conclusions CRISP can be delivered in AAA-surveillance, but fidelity of delivery is low. The intervention and its training need to be refined/tested before wider implementation. Registration ISRCTN9399399518/11/20).