(1) Background: Providing the patient with the health care they need in a personalized and appropriate manner and without adverse effects (AEs) is a part of quality of care and patient safety. The aim of this applied research project was the assessment of AEs as a clinical risk in patients with high social vulnerability such as persons with intellectual and developmental disabilities (PwIDD). (2) Methods: A retrospective epidemiological cohort study was performed on exposed and unexposed groups (the control group) in order to estimate the incidence of AEs in PwIDDs and assess their importance for this category of patients. (3) Results: AEs were observed with a frequency of 30.4% (95% CI) in the PwIDD exposed group, with significant differences to the unexposed group (p = 0.009). No differences were observed with regards to gender. Age was as a marker of care risk, with the highest incidence of AEs in the group of 60-69 years. (4) Conclusions: PwIDDs have a high risk of suffering AEs while receiving health care assistance due to their high social and clinical vulnerability. Health care practitioners must therefore be aware of these results and keep these observations in mind in order to carry out personalized, preventive, competent, effective, and safe medical care.
Keywords: adverse effects; care quality; patient safety; persons with intellectual and developmental disabilities.