ASSOCIATION BETWEEN TOXOPLASMA GONDII OOCYST IGG AND INSOMNIA IN THE OLD ORDER AMISH

Toxoplasma gondii (T.gondii), infects central nervous tissue and is kept in relative dormancy by the immune system. Sleep disturbances were found to precipitate mental illness, suicidal behavior and car accidents, also previously linked to T.gondii. Foodborn infection is common and occurs via ingestion of oocysts or tissue cysts. The T. gondii oocysts is resistant to disinfectants and more virulent than tissue cysts. If sleep disruption, particularly insomnia, would mediate the link between T gondii and behavioral dysregulations, then sleep disruption and T.gondii, in particular via the oocyst infection, will be positively associated. Sleep questionnaires from 2031 Old Order Amish were analyzed in relationship to T. gondii and oocyst-specific IgG antibodies measured by ELISA (N=833). Ranked answers on sleep-related problems (difficulty falling or staying asleep and problems during the day due to poor sleep) questions were approximated as continuous variables and compared between the three groups-a) T.gondii negative b) T. gondii positive Oocyst negative and c) T.gondii positive oocyst positive, using ANCOVAs (with adjustment for age and sex), with Tuckey posthoc tests. There was a significant effect of T,gondii /oocyst category (p<0.05) with significant posthoc differences in only between T.gondii negative and T.gondii positive/Oocyst positive subjects and only for difficulty staying asleep (p=0.019), and day-time problems due to poor sleep (p=0.045). Finding an association with insomnia markers only for oocyst positive participants suggests more impactful physiological effects for the oocyst form of infection. Studying these associations in the Amish reduces heterogeneity based on lifestyle and drug/alcohol intake.The mechanisms for such an association may involve dopamine production by T. gondii, or effects of immune activation necessary to keep it in check. Joint Institute for Food Safety and Applied Nutrition and the U.S. Food and Drug Authority (U.S. FDA) through their cooperative agreement FDU.001418 (PI Postolache), 1 I01 CX001310-01 from CSR&D/ Veterans Affairs Administration (PI Postolache), and the P30DK072488 NIDDK (NORC - child project developmental grant Postolache) from the National Institutes of Health, Bethesda, MD, USA.