Task: Question Answering
Input (English): Context: Ehlers-Danlos syndromes (EDSs) constitute a rare group of inherited connective tissue diseases, characterized by multisystemic manifestations and general tissue fragility. Most severe complications include vascular and gastrointestinal (GI) emergencies requiring acute surgery. The purpose of this systematic review was to assess the causes of GI-related surgery and related mortality and morbidity in patients with EDSs. A systematic search was conducted in PubMed, Embase, and Scopus to identify relevant studies. Preferred Reporting Items for Systematic Reviews and Meta-Analysis guidelines for systematic reviews were followed. According to eligibility criteria, data were extracted and systematically screened by 2 authors. Screening process identified 11 studies with a total of 1,567 patients. Findings indicated that patients with EDSs had a higher occurrence of surgery demanding GI manifestations, including perforation, hemorrhage, rupture of intra-abdominal organs, and rectal prolapse. Most affected was the vascular subtype, of which up to 33% underwent GI surgery and suffered from a lowered average life expectancy of 48 years (range 6-78). Secondary complications of surgery were common in all patients with EDSs. Studies suggested that patients with EDSs present an increased need for GI surgery, but also an increased risk of surgery-related complications, most predominantly seen in the vascular subtype. 
 Question: What tissue is most affected in Ehlers-Danlos syndromes?
Output (English): connective tissue