Association of common infections with cognitive performance in the Baltimore Epidemiologic Catchment Area study follow-up

INTRODUCTION

Growing evidence suggests that some common infections are causally associated with cognitive impairment; however, less is known about the burden of multiple infections.

METHODS

We investigated the cross-sectional association of positive antibody tests for herpes simplex virus, cytomegalovirus (CMV), Epstein-Barr virus (EBV), varicella zoster virus (VZV), and Toxoplasma gondii (TOX) with Mini-Mental State Examination (MMSE) and delayed verbal recall performance in 575 adults aged 41-97 from the Baltimore Epidemiologic Catchment Area Study.

RESULTS

In multivariable-adjusted zero-inflated Poisson (ZIP) regression models, positive antibody tests for CMV (p = .011) and herpes simplex virus (p = .018) were individually associated with poorer MMSE performance (p = .011). A greater number of positive antibody tests among the five tested was associated with worse MMSE performance (p = .001).

DISCUSSION

CMV, herpes simplex virus, and the global burden of multiple common infections were independently associated with poorer cognitive performance. Additional research that investigates whether the global burden of infection predicts cognitive decline and Alzheimer's disease biomarker changes is needed to confirm these findings.

Neurological and Neurobehavioral Disorders Associated with Toxoplasma gondii Infection in Humans

The intracellular parasite Toxoplasma gondii is estimated to infect up to 30% of the world population, leading to lifelong chronic infection of the brain and muscle tissue. Although most latent T. gondii infections in humans have traditionally been considered asymptomatic, studies in rodents suggest phenotypic neurological changes are possible. Consequently, several studies have examined the link between T. gondii infection and diseases such as schizophrenia, epilepsy, depression, bipolar disorder, dysphoria, Alzheimer's disease, Parkinson's disease, and obsessive-compulsive disorder (OCD). To date, there is varying evidence of the relationship of T. gondii to these human neurological or neurobehavioral disorders. A thorough review of T. gondii literature was conducted to highlight and summarize current findings. We found that schizophrenia was most frequently linked to T. gondii infection, while sleep disruption showed no linkage to T. gondii infection, and other conditions having mixed support for a link to T. gondii. However, infection as a cause of human neurobehavioral disease has yet to be firmly established.

A loop-mediated isothermal amplification (LAMP) assay for detection of Toxoplasma gondii infection in women with spontaneous abortion

The present study aimed to use the loop-mediated isothermal amplification (LAMP) technique in comparison with serological tests to determine the rate of T. gondii infection in women suffering from spontaneous abortion (SA). A total of 140 women suffering from their first SA were included in this study. The collected aborted fetal remains and blood samples from each patient were examined in sterilized conditions using the LAMP technique and ELISA. Of the 140 women, 80 (57.1%) tested seropositive for anti-Toxoplasma antibodies by ELISA, 72 (51.4%) women tested seropositive for the IgG antibody, 8 (5.7%) tested seropositive for the IgM antibody. Among the eight women who'd had their first SA who tested seropositive for IgM antibody by ELISA, only five cases (62.5%) reported positively to the LAMP test. The difference in the frequency distribution of the LAMP results for measuring the Toxoplasma infection in pregnant women under study was statistically significant (P < 0.001) from the results of the serological test (ELISA). Although there was a significant difference between age and positivity in the LAMP test (P = 0.017), no significant difference was observed between positivity in the LAMP test and other variables. The findings of the present investigation suggest that LAMP is a preferred method for determining Toxoplasma infection in pregnant women suffering from SA compared with other routine serological tests. Even in a field with limited facilities and equipment, this technique can be effective and efficient in accurately and specifically diagnosing Toxoplasma infections in women at high risk of SA.

Toxoplasma gondii infection and risk of Parkinson and Alzheimer diseases: A systematic review and meta-analysis on observational studies

In the past decade, Toxoplasma gondii infection has been recognized as a potential risk for many psychiatric and neurological disorders. We performed this systematic review and meta-analysis to evaluate the association between Toxoplasma infection and Parkinson's and Alzheimer's diseases. PubMed, Web of science, Scopus and Embase databases were searched up to September 30, 2018 for studies that reported risk of Parkinson's and Alzheimer's diseases associated with Toxoplasma infection. We used a random effects meta-analysis model to generate the pooled odds ratio (OR) with 95% confidence intervals (CIs). Eleven studies, including seven studies for Parkinson's disease (428 patients and 540 controls) and four studies for Alzheimer's disease (301 patients and 313 controls), were included in the meta-analysis. We found that there was no statistically significant association between Toxoplasma infection, as determined by IgG serology, IgM serology, and PCR with increased risk of Parkinson's disease (OR, 1.14; 95% CI, 0.78-1.68), (OR, 1.61; 95% CI, 0.33-7.76) and (OR, 1.87; 95% CI, 0.43-8.05), respectively. The OR for association of Toxoplasma infection, based on IgG serology with Alzheimer's patients, compared to control group, was (OR, 1.38; 95% CI, 0.99-1.92), demonstrating a marginally significant association between Toxoplasma infection and Alzheimer's disease. Our findings do not support a general hypotheses regarding an associative relationship between Toxoplasma infection and Parkinson's disease, but do support a marginally significant association between Toxoplasma infection and Alzheimer's disease; this association should be investigated further through longitudinal and experimental studies.

It's Never Too Early or Too Late-End the Epidemic of Alzheimer's by Preventing or Reversing Causation From Pre-birth to Death

The path to sporadic Alzheimer's is a tragic journey beginning prior to birth and ending in the most dreaded disease of society. Along the disease path are a myriad of clues that portend AD, many of which are complaints of seemingly unrelated conditions from chronic migraines, mood disorders, eye diseases, metabolic syndromes, periodontal diseases, hormonal and autoimmune diseases. Properly treating, not just managing, these diseases, prior to onset of dementia, may significantly reduce dementia incidences. Current high levels of health complaints reflect a state of generalized poor health and compromised immunity. During the mid-Victorian era, people were long-lived yet healthy, suffering from chronic diseases at one tenth the rate of peoples today. It's our poor health, at any age that increases susceptibility to chronic diseases and Alzheimer's. Infection is involved in many cases of Alzheimer's and other neurodegenerative diseases but is also implicated in many chronic conditions. Scientists looking for causation recognize that Alzheimer' is multifactorial and systemic-not "brain only." To slow, stop and reverse the AD epidemic, identification and reversal of causal factors must occur across the entire life spectrum of humans. This approach simply gives consideration to enhancing immune status of our bodies and brain, and controlling inflammation and infection, throughout the entire age spectrum. Infection is a causal factor, but the root cause is multi-factorial and immune health related. Pasteur stated it best when acknowledging the work of Bernard in 19th Century France, "The seed is nothing, the soil is everything."