Positive association between Toxoplasma gondii IgG serointensity and current dysphoria/hopelessness scores in the Old Order Amish: a preliminary study
Wadhawan Abhishek,
Dagdag Aline,
Duffy Allyson,
Daue Melanie L.,
Ryan Kathy A.,
Brenner Lisa A.,
Stiller John W.,
Pollin Toni I.,
Groer Maureen W.,
Huang Xuemei,
Lowry Christopher A.,
Mitchell Braxton D.,
Postolache Teodor T.
Affiliations
Wadhawan Abhishek
Mood and Anxiety Program, Department of Psychiatry, University of Maryland School of Medicine, Baltimore, MD, USA
Dagdag Aline
Mood and Anxiety Program, Department of Psychiatry, University of Maryland School of Medicine, Baltimore, MD, USA
Duffy Allyson
College of Nursing, University of South Florida College of Nursing, Tampa, FL, USA
Daue Melanie L.
Division of Endocrinology, Diabetes and Nutrition, Department of Medicine, University of Maryland School of Medicine, Baltimore, MD, USA
Ryan Kathy A.
Division of Endocrinology, Diabetes and Nutrition, Department of Medicine, University of Maryland School of Medicine, Baltimore, MD, USA
Brenner Lisa A.
Departments of Psychiatry, Physical Medicine and Rehabilitation, and Neurology, University of Colorado, Anschutz School of Medicine, Denver, CO, USA
Stiller John W.
Mood and Anxiety Program, Department of Psychiatry, University of Maryland School of Medicine, Baltimore, MD, USA
Pollin Toni I.
Division of Endocrinology, Diabetes and Nutrition, Department of Medicine, University of Maryland School of Medicine, Baltimore, MD, USA
Groer Maureen W.
College of Nursing, University of South Florida College of Nursing, Tampa, FL, USA
Huang Xuemei
Department of Neurology, Pennsylvania State University-Milton S. Hershey Medical Center, Hershey, PA, USA
Lowry Christopher A.
Rocky Mountain Mental Illness Research Education and Clinical Center (MIRECC), Veterans Integrated Service Network (VISN) 19, Military and Veteran Microbiome: Consortium for Research and Education (MVM-CoRE), Denver, CO, USA
Mitchell Braxton D.
Division of Endocrinology, Diabetes and Nutrition, Department of Medicine, University of Maryland School of Medicine, Baltimore, MD, USA
Postolache Teodor T.
Mood and Anxiety Program, Department of Psychiatry, University of Maryland School of Medicine, Baltimore, MD, USA
Toxoplasma gondii (T. gondii) IgG seropositivity and serointensity have been previously associated with suicidal self-directed violence (SSDV). Although associations with unipolar depression have also been investigated, the results have been inconsistent, possibly as a consequence of high heterogeneity. We have now studied this association in a more homogeneous population, [that is (i.e.) Old Order Amish (OOA)] with previously reported high T. gondii seroprevalence. In 306 OOA with a mean age of 46.1±16.7 years, including 191 (62.4%) women in the Amish Wellness Study, we obtained both T. gondii IgG titers (by enzyme-linked immunosorbent assay [ELISA]), and depression screening questionnaires (Patient Health Questionnaire [PHQ-9] [n=280] and PHQ-2 [n=26]). Associations between T. gondii IgG and dysphoria/hopelessness and anhedonia scores on depression screening questionnaires were analyzed using multivariable linear methods with adjustment for age and sex. Serointensity was associated with both current dysphoria/hopelessness (p=0.045) and current combined anhedonia and dysphoria/hopelessness (p=0.043), while associations with simple anhedonia and past/lifelong (rather than current) phenotypes were not significant. These results indicate the need for larger longitudinal studies to corroborate the association between dysphoria/hopelessness and T. gondii IgG-titers. Current hopelessness is a known risk factor for SSDV which responds particularly well to cognitive behavioral therapy, and may be a focused treatment target for T. gondii-positive individuals at high-risk for SSDV.
