Journal of Medical Case Reports and Reviews 2:10 (2019) Available online at www.jmcrr.info ISSN (O) 2589-8655| (P) 2589-8647 JMCRR 2019, 2:10, Page No: 370-380 Page 370 “ASSOCIATION BETWEEN PARTICULATE MATTER AND ALZHEIMER'S DISEASE IN ELDERLY SUBJECTS” Dr Nasira Tajamal,Co Authors: Dr Raymond Knutsen, Dr Larry Beeson, Dr Maryam Tajamal, Dr Rehan Tajamal Dr Salman Tajamal, Received 12 Sep 2019; Accepted 14 Sep 2019; Publish Online 15 oct 2019 Introduction: Alzheimer's disease (AD) is an age-related, progressive, neurodegenerative disorder, affecting more than 4 million people in the US and more than 30 million people worldwide [1]. The pathological changes seen in the brain are plaque formations consisting mainly of amyloid beta (Aβ) protein deposits surrounded by neurons containing neurofibrillary tangles. Associated with Aβ-containing senile plaques are reactive microglia and activated microphages producing cytokines like IL-1, IL-6 and TNF-α, as well as acute phase proteins, indicating inflammation [2]. Also associated with the plaque deposition is vascular damage and neuronal loss in the area of hippocampus and frontal cortex, leading to severe memory loss [3, 4]. Environmental gases like ozone, together with particulate matter (PM) and organic compounds, in outdoor and indoor air forms the complex mixture of air pollution [4]. Studies indicate that chronic exposure to particulate matter may increase oxidative stress by producing reactive oxygen species (ROS) and chronic neuroinflammation, which may be for- runners for AD and other neurodegenerative disorders [1, 3, 5] Findings indicate that there is an association between particulate matter and neurodegenerative processes [2, 5]. Animal studies have added to the concerns that air pollution containing PM may contribute to AD and other CNS outcomes through some of the mechanisms presented above([3] Increasing size of the aging population may in part explain the increasing incidence of AD, but environmental factors like particulate matter may also be an important contributing factor [3]. Increasing AD incidence with accompanying cognitive decline and memory loss posts serious economic, social and health delivery problems at a global scale. Studies have indicated that air pollution, largely caused by increasing urbanization [2, 6]and [7] may be of etiologic importance. After going through various studies showing a possible relationship between PM and AD I wanted to test the hypothesis that an association exists between exposure to PM and AD. Air pollution containing PM, ozone, carbon monoxide, nitrogen dioxide, sulfur dioxide, and lead is largely found in urban atmosphere. In this review paper my focus is on ambient air PM. Several studies have demonstrated the ability of PM to cross the blood-brain barrier and reach the CNS. However, PM may also reach the brain through the systemic circulation. Hence the purpose of this review paper is to explore the relationship between ambient air PM and AD in elderly subjects in order to learn whether AD may be, to some extent, a preventable disease. Methods: Studies were identified by searching PubMed, Google Scholar, and Scopus, keeping Air pollution, Particulate Matter, Alzheimer’s disease, Cognitive Impairments and Dementia as the main searching words. In this systematic review we wanted to include all published studies that provide results of AD among patients exposed to ambient air PM in the general population. For inclusion into the systematic review papers, therefore, the following criteria had to be met: study subjects had to be recruited at the population level (i.e., not hospital based) to make them representative of the underlying population and less susceptible to selection bias. Different