Systemic symptom patterns in implant-associated ASIA and breast implant illness: a study-level descriptive systematic review

Background Systemic symptoms reported after exposure to implantable biomaterials—particularly breast implants—are frequently discussed under the debated constructs of ASIA and breast implant illness (BII). The evidence base is heterogeneous and largely non-randomized, complicating interpretation and patient counseling in aesthetic practice. Methods A PRISMA-aligned descriptive systematic review was conducted using the study as the unit of analysis. The findings were summarized as study-level reporting proportions of systemic symptom domains, without estimating prevalence, associations, or clinical risk. Results Ten studies met eligibility criteria for study-level synthesis. Breast implants were the most frequently reported exposure (8/10 studies), with dermal fillers reported in 2/10. Musculoskeletal and constitutional symptoms were most consistently reported: arthralgia/arthritis (10/10), chronic fatigue (9/10), and myalgia (9/10). Neurological manifestations (8/10) and cognitive disturbances (7/10) were also common. Symptom reporting varied across studies, reflecting heterogeneity in symptom inventories and ascertainment. Conclusions Across the eligible literature, study-level reporting most consistently described musculoskeletal, constitutional, and neurocognitive symptom domains in patients with implant-associated ASIA/BII. However, these findings represent descriptive reporting patterns and do not establish patient-level prevalence, causality, clinical predictability, or a validated clinical syndrome. Their primary relevance lies in supporting transparent, uncertainty-aware patient counseling within a heterogeneous and methodologically limited evidence base. Level of evidence: not gradable.