The chronic illness community has been saying for years that hEDS, POTS, and MCAS cluster together. Research is now extending that cluster to include ADHD and autism, and finally testing it at population scale. A 2025 preprint by Pearson et al. analyzed over 23 million patient records and found hEDS patients are significantly more likely to develop long COVID, especially with overlapping POTS or mast cell symptoms. A 2025 European Psychiatry editorial synthesized evidence that hypermobility, imm