Navy Asbestos Medical Surveillance Program: 19801999

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• Navy Asbestos Medical Surveillance Program
  1980-1999
• AFEB 19 Feb 2003
• CAPT Bruce K Bohnker, MC, USN(FS)
• Navy Environmental Health Center
• Portsmouth VA 23708
• 757-953-0710 (DSN 377-0710)
• Bohnkerb_at_nehc.med.navy.mil

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AMSP 1980-1999

• History/Background
• Literature
• Smoking 1995-1999
• PFT analysis
• AMSP1980-1990
• AMSP1990-1999
• Discussion

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AMSP 1980-1999
Think Populations
See Individuals
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History Navy Asbestos

• Extensive Exposure from Ships, Shipyards, and
  other sources
• Federal Guidance changed in 1970s to reduce
  exposure.
• NAVOSH limits changed, AMSP created

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AMSP1980-1999

• Began late 1970s
• Civil service AD
• History PE Form
• 1979, 1983, 1990
• initial, periodic, termination
• Radiograph Form
• 1979, 1990

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AMSP- Form/Data Base History

• Computer Programs
• NMIMC flat file
• NEHC file (Dbase III)
• Y2K -gt MS Access
• Analysis SPSS/ Epi-info
• Management Changes
• 300K records 1980-90
• 150K records 1990-99

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AMSP Past Medical Literature
Chest 1990 Apr 97(4)810-3. Chest 1989, June
95(6) 1262-4. J. Occup Med. 1988 Aug
30(8)644-7. J. Occup Medicine 1983 25864-870.
Cancer Research, 1985 Aug 45(8) 3924-8. ()
NEHC authors
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AMSP 1995-1999 Smoking Demographics

• Initial review of data
• Summer 2000
• Programmatic review
• ACCESS 1997, then dBase III, then SPSS and
  EPI-INFO
• Y2K transition Process
• Population Size
• Changes over time
• Military Medicine Nov 2001

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AMSP 1995-1999

• Study design Choose AMSP records received
  1995-1999 for ease of analysis. (multiple records
  per person).
• 79,598 records
• Some delay in submission
• 15th-20th year of program
• Population demographics
• Current Smoking status (outcome variable)

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N79,598
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AMSP 1995-1999 Mean age of personnel
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Chi Square for Trend 8.5, p.00
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Chi square for trend 90.795, p 0.00
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Chi Square for Trend 4.367, p .03655
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AMSP 1995-1999Logistic Regression for
Current Smoking Navy AD
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AMSP 1995-1999Logistic Regression for
Current Smoking Civil Service
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AMSP Discussion Demographics and Smoking

• Population is aging and decreasing in size.
• Most have only past exposure
• Smoking lowest for past exposure
• Smoking rates decreasing
• Continued study warranted
• Thanks to MTF/clinics

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AMSP 1980-1999 PFT

• Examine effect of asbestos exposure on pulmonary
  functions over time
• FEV1 and FVC were measured on forms in 10 ml units

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Data Analysis Issue

• 1990 Form changed to allow asbestos exposure in
  years
• Asbestos Exposure categorical before 1990, then
  linear
• Lead to Two analysis 1984-1990, 1991-1999
• Linear Regression Modeling

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AMSP Independent Variables for Linear Regression
Model

• Continuous variables
• Age (yr)
• Smoking exposure(yr)
• Asbestos exposure (yr)
• Weight (pounds)
• Height(inches)
• Year of Examination (why?)

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AMSP Dependent Variables

• Pulmonary function changes over time
• FEV1
• FVC
• Decrease with age, smoking exposures

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AMSP 1980-1990

• NAVMED 6260/5 (10/83)- categorical asbestos
  exposure (0, 1, 1-5, 5-15,15 yr)
• White Males
• Height 59-79 inches
• Age 30-60 yrs
• Weight 100-360 lbs
• Mid-period estimate for asbestos exposure
• 120,000 records

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Exams by Year(1980-1990)
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FEV1 1984-1990 (in ml) (mid-period estimate for
exposure)
R.610
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FVC 1984-1990 (in ml) (mid-period estimate for
exposure)
R.670
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PFT Changes for Categorical Asbestos Exposure
(In ml)
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PFT Changes for Categorical Asbestos Exposure(In
ml)
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AMSP PFT Summary 1984-1990

• Statistically Significant effect demonstrated
  from asbestos exposure
• Effect demonstrated for over 5 years exposure
• Improvement with advanced year of examination

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1991-1999 Study Design

• 1991 Change in Form
• Asbestos exposure in years rather than
  categorical duration
• None, Prior, Direct, Indirect exposure grouping
• Linear regression model
• Same exclusion criteria

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1991-1999 FEV1 All Records in ml/yr
R.578
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1991-1999 FVC All Records in ml/yr
R.581
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1991-1999 FEV1 None Prior Records in ml/yr
R.575
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1991-1999 FVC None Prior Records in ml/yr
R.580
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1991-1999 FEV1 None Direct Records in ml/yr
R.574
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1991-1999 FVC None Direct Records in ml/yr
R.584
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1991-1999 FEV1 None Indirect Records in ml/yr
R.582
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1991-1999 FVC None Indirect Records in ml/yr
R.580
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AMSP Linear Regression for FEV1 FVC 1991-1999

• Asbestos Exposure has small effect at worse, and
  ? protective
• Prior exposure more important than current
• Interaction for Smoking and Asbestos

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Study Limitations

• Cross sectional analysis
• White males only
• ? Lost to follow up
• Not likely to provide insights on cancers
• Year of examination

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Appreciation

• Thanks to the clinical staff who have supported
  AMSP. A huge amount of effort has been required
  at the deck plate caring for our workforce. The
  current war has demonstrated that our technology
  allows us to fight and win. However, those
  technologies pose risks to our workers, just as
  asbestos did.

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Asbestos Medical Surveillance Program1980-1999

• CAPT Bruce K. Bohnker MC USN(FS)
• NEHC-PM
• Portsmouth VA 23708
• 757-953-0710
• Bohnkerb_at_nehc.med.navy.mil