Pre-endovascular intervention C-reactive protein levels and its association with femoropopliteal artery restenosis – a systematic review and meta-analysis

Background Endovascular interventions have traditionally been used to manage atherosclerotic disease affecting the femoral and popliteal arterial domains. High restenosis rates in these treated lesions represent a prominent clinical challenge. Elevated C-reactive protein (CRP) levels, a marker of systemic inflammation, has previously been linked to coronary restenosis, however, its association with femoropopliteal artery restenosis remains to be unclear. Purpose We conducted a systematic review and study-level meta-analysis to assess the association between pre-procedural CRP levels and subsequent femoropopliteal artery restenosis. Methods Online search using appropriate search strings was conducted on databases of PubMed, EMBASE, MEDLINE-OVID, Scopus and Web of Science for relevant articles published until 30th September 2025. Studies reporting summary-level pre-procedural CRP levels in patients with and without the incidence of femoropopliteal restenosis during follow-up were included. Study-level data were pooled to obtain pooled standardized mean difference (SMD) and its 95% confidence intervals (CI), employing a z-test and a random effects model. Publication bias assessment was conducted visually using Begg’s funnel plot, while its statistical estimates were calculated using Egger’s test. The resultant p<0.05 indicated statistical significance. Obtained pooled results were further tested for robustness using a leave-one-out sensitivity analysis. Results After screening a total of 331 unique articles, 14 studies comprising of 2,097 patients (562 ISR cases/1,535 controls) were included for quantitative synthesis. Pooled results suggested higher pre-procedural CRP levels in patients who later developed femoropopliteal artery restenosis as compared to those who did not. (SMD= 0.44, 95% Cl= 0.09-0.78, p= 0.01). (Figure 1.) We found no evidence of publication bias, both visually via Begg’s funnel plot and statistically via Egger’s test results (p= 0.52). Our leave-one-out sensitivity analysis further attested to the robustness of our pooled results. (Figure 2.) Conclusions The present systematic review and study-level meta-analysis suggests an association between elevated pre-procedural CRP levels and subsequent femoropopliteal artery restenosis. Our findings should however be interpreted with caution and further large-scale prospective investigations are warranted to substantiate our results.