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 with patients and stakeholders, 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 across Leicestershire and Rutland AAA screening/surveillance programmes. Those who consented to take part were followed-up with cardiovascular-assessments. Fidelity of intervention-delivery was assessed quantitatively and qualitatively. Results 40 men (mean age 75 + 7 years) took part over four months and were 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 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 and viewed as beneficial by patients and HCPs. Based on qualitative interviews and observations, the low fidelity of intervention-delivery was due to intervention-training not being detailed. Conclusions The CRISP intervention can be delivered in AAA-surveillance, but the fidelity of delivery is low. The intervention and its training course need to be refined and tested before wider implementation. Registration ISRCTN (ISRCTN93993995; 18/11/2020).