World Trade Center Exposures, Neuropathic Symptoms and Nervous System Injury

Details

• Personal Author:
  Marmor M
• Description:
  Our activities during this reporting period included (a) data analysis and development of a publication using longitudinal data on paresthesia and (b) completion of data collection, data analysis and preparation of a manuscript for publication of our case-control study of paresthesia. The specific aims of our project were (1) to analyze longitudinal data to describe the trajectories of paresthesias in the survivor population; (2) to analyze already-obtained electromyography/nerve conduction velocity (EMG/NCV) data in order to investigate the pathophysiology of the reported paresthesias; and (3) to examine via a case-control study whether neuropathic symptoms among Survivors were associated with abnormalities in nerve fiber densities or nerve conduction velocities, and whether they might be due not to WTC exposure, but to other medical conditions known to cause paresthesia. Our work focused on Survivors (with primarily non-rescue/recovery WTC exposures) enrolled in the WTC Environmental Health Center (WTC EHC), Bellevue Hospital, New York, NY. In pursuit of Aim 1 we studied times to paresthesia among 3,411 WTC EHC patients. Paresthesia was defined as present if the symptom occurred in the lower extremities with frequency "often" or "almost continuous." We plotted hazard functions and used the log-rank test to compare time to onset of paresthesia between different exposure groups. We also used Cox regression analysis to examine risk factors for time-to-paresthesia after 9/11/2001 and calculate hazard ratios adjusted for potential confounders. We found significantly elevated hazard ratios for paresthesia for (a) working in a job that required cleaning of WTC dust in the workplace; and (b) being heavily exposed to WTC dust on September 11, 2001, after adjusting for age, race/ethnicity, depression, anxiety, post-traumatic stress disorder, and body mass index. These data thus were consistent with the hypothesis that exposure to WTC dust or some other aspect of cleaning WTC dust in the workplace, led to development of associated with neuropathy and paresthesia. In pursuit of Aim 2, we reviewed the electronic medical records of a sample of the approximately 80 individuals whose records had indicated referral for EMG/NCV. In a random sample of 10 of these patients, we found that 6 had never undergone this testing (having been referred, but never showing up for the testing), 3 had normal results, and 1 was found to have carpal tunnel syndrome, most likely not caused by WTC-associated factors. Due to these findings, Aim 2 was not further pursued. In pursuit of Aim 3, we have completed a case-control study and submitted a manuscript for publication. The goal of the study was to investigate whether paresthesia of the lower extremities, commonly reported by individuals exposed to the World Trade Center (WTC) disaster of September 11, 2001, was associated with objective signs of neuropathy, metabolic abnormalities or neurotoxin exposures. We used a case-control design to compare paresthesia cases presenting at the Bellevue Hospital WTC Environmental Health Center (EHC) with "clinic controls" (WTC EHC clinic patients who did not report paresthesias), and "community controls" (persons unexposed to the WTC disaster). We contrasted 41 WTC EHC patients with neuropathic symptoms ("cases") with 38 controls free of neuropathic symptoms. Controls were frequency-matched to cases on age and gender, and absence of histories of (a) paresthesia prior to 9/11/2001, (b) diabetes, (c) treatment with chemotherapeutic agents for cancer, (d) treatment with antiretroviral drugs, (e) vitamin B12 deficiency, and (f) bleeding disorders and treatment with Coumadin or other blood thinners. In addition, a community-based control group of 20 individuals was enrolled to determine the prevalence of paresthesias and risk factors for paresthesias among similar, but non-WTC-exposed individuals. Subjects responded to questionnaires, had neurologic evaluations, and donated blood for analysis of hemoglobin A1c, fasting glucose, vitamin B12, methylmalonic acid, syphilis (VDRL); vitamin B12, methylmalonic acid, antinuclear antibody (ANA), C-reactive protein (CRP), Lyme disease antibodies, serum protein electrophoresis (SPEP) with immunofixation, celiac disease antibodies (i.e., antibodies to deamidated gliadin), and lead. Paresthesia cases had skin punch biopsies to obtain intraepidermal nerve fiber density and sweat gland nerve fiber density, and nerve conduction studies. We found scores on the Norfolk Diabetic Neuropathy Quality of Life, the Utah Early Neuropathy Scale, the Michigan Neuropathy Screening Instrument, and a standardized neurological history and examination were significantly higher (worse) in cases than controls. Intraepidermal or sweat gland nerve fiber densities were abnormally low in 57% of cases; nerve conduction velocities were abnormally low in 3%. Neurologic abnormalities were uncommon among community controls. Parethesia cases did not have increased markers of diabetes, vitamin deficiencies, or other common etiologies of neuropathy. We concluded that paresthesias among WTC-exposed individuals were associated with increased signs of neuropathy and reduced small nerve fiber densities. The data support the hypothesis that WTC exposure was an independent risk factor for neuropathic symptoms, and did not support alternative, non-WTC etiologies. [Description provided by NIOSH]
• Subjects:
  Aging Diagnosis Environmental Exposure Hazardous Substances Health Care Facilities Workforce And Services Mental Health Musculoskeletal Diseases Musculoskeletal System Nervous System Nervous System Diseases Occupational Health Pathology Race Factors Risk Assessment Risk Factors Safety September 11 Terrorist Attacks

  More +
• Keywords:
  Age Groups BMI Body Mass Index Carpal Tunnel Syndrome Case Control Studies Clean-up Hazards CTS Diagnostic Techniques Disaster Clean-up Electromyography Environmental Exposure Etiology Exposure Assessment Exposure Levels Hazardous Materials Hazardous Waste Cleanup Hazards Humans Medical Examinations Medical Monitoring Medical Screening Mental Health Metabolic Disorders Nerve Fibers Nerve Function Neurological Disorders Neuromotor System Neuropathy Neurotoxins Peripheral Nervous System Physiology Post-traumatic Stress Disorder PTSD Racial Factors Risk Factors Sampling World Trade Center WTC

  More +
• Series:
  Grant Final Reports
• Publisher:
  National Institute for Occupational Safety and Health
• Document Type:
  Text
• Funding:
  Cooperative Agreement
• Genre:
  Final Cooperative Agreement Report
• Place as Subject:
  New York ; OSHA Region 2
• CIO:
  National Institute for Occupational Safety and Health (NIOSH)
• Division:
  OEP - Office of Extramural Programs
• Topic:
  Workplace Safety & Health
• Location:
  North America
• Pages in Document:
  1-11
• NIOSHTIC Number:
  nn:20066172
• Citation:
  Atlanta, GA: U.S. Department of Health and Human Services, Public Health Service, Centers for Disease Control and Prevention, National Institute for Occupational Safety and Health, U01-OH-011305, 2019 Nov; :1-11
• Contact Point Address:
  Michael Marmor, PhD, One Park Avenue New York, NY 10016
• Email:
  Michael.Marmor@nyulangone.org
• Federal Fiscal Year:
  2020
• Performing Organization:
  New York University School of Medicine
• Peer Reviewed:
  False
• Start Date:
  20160901
• Source Full Name:
  National Institute for Occupational Safety and Health
• End Date:
  20180831
• Collection(s):
  National Institute for Occupational Safety and Health
• Main Document Checksum:
  urn:sha-512:a21fafbd7278877f479f774f356374b81169bad9f26cd55bb6113f8e14ecac0c509d99c7528d8dc70db5c3ddadedfaa5c01e27c17755ececefe80ff26927dc2f
• Download URL:
  https://stacks.cdc.gov/view/cdc/219145/cdc_219145_DS1.pdf
• File Type:
  [PDF - 385.91 KB ]