National Burden, Health System Variation And Temporal Trends In Antimicrobial Resistance Among Hospitalized Patients In Nigeria: A Systematic Review And Meta-Analysis

Background: Antimicrobial resistance (AMR) poses a major threat to global health, with sub-Saharan Africa experiencing a disproportionate burden of resistant bacterial infections. Nigeria has implemented two successive National Action Plans (NAPs) on AMR to strengthen surveillance, antimicrobial stewardship, infection prevention and control, and laboratory capacity. We aimed to descriptively estimate the burden of AMR among hospitalized patients in Nigeria and examine variations across the Pre-NAP, NAP 1.0, and early NAP 2.0 implementation periods, as well as health-system and microbiological characteristics.&nbsp;<br><br>Methods: We conducted a systematic review and meta-analysis of observational studies reporting bacterial antimicrobial resistance among hospitalized patients in Nigeria. Studies were categorized by period of data collection into Pre-NAP, NAP 1.0 and NAP 2.0 phases. Random-effects meta-analysis models estimated pooled AMR prevalence and antibiotic resistance rates, with 95% confidence intervals (CIs). Prespecified subgroup analyses explored variation by NAP phases, health-system and microbiological characteristics (PROSPERO CRD420261337982).&nbsp;<br><br>Findings:&nbsp;185 studies comprising 69,213 participants and 39,954 bacterial isolates were included. The pooled prevalence of AMR among hospitalized patients was 48.5% (95% CI: 39.6–57.5%), while the pooled antibiotic resistance rate across pathogen–antibiotic combinations was 59.6% (95% CI: 52.4–66.4%). AMR prevalence was lower during NAP 1.0&nbsp; (44.6% [33.2 –56.7]) compared with the Pre-NAP period&nbsp; (65.3% [35.2–86.7]), but it subsequently rose to (58.9% [21.2–88.4]) during early NAP 2.0. Organism-level resistance rates were higher in NAP 1.0&nbsp; (65.1% [55.4-73.7]) than Pre-NAP (44.1% [24.1–66.2]), with lower estimates observed during early NAP 2.0 (46.8% [15.8–80.5]). AMR estimates were higher in secondary facilities than tertiary hospitals. Resistance was particularly high among Enterococcus faecalis, Serratia spp and Pseudomonas aeruginosa and across sulfonamides, cephalosporins and beta-lactams. Overall, substantial between-study and within-study heterogeneity persisted across all subgroup analyses.&nbsp;<br><br>Interpretation: AMR remains a substantial and persistent challenge among hospitalized patients in Nigeria despite successive national policy initiatives. Although causal inferences regarding policy effectiveness cannot be drawn from these data, the persistently high burden of AMR highlights the need for sustained investment in routine microbiological surveillance, antimicrobial stewardship, infection prevention and control, and laboratory capacity strengthening, particularly in secondary and private healthcare facilities.&nbsp;Funding: No specific funding was received for this study.​