To determine whether specific immune-related comorbidities tend to group together, we assessed the relative risk of each comorbidity given the presence of another using a pairwise comparison matrix for all conditions in Table 3. Frequent throat/ear infections, scarlet fever, and RF—all potential consequences of streptococcal infection—showed significant pairwise associations (Supplementary Table S4 and Fig. 1). Moreover, asthma was associated with frequent throat/ear infections; SLE with RA; psoriasis with RA, MS, and asthma; and RF with IBD. These data identify groups of conditions with potential shared etiology and common environmental and genetic risk factors.
