Georgia epidemiology report, Vol. 13, no. 5 (May 1997)

Georgia

Epidemiology

Report

The Georgia Epidemiology Report is a publication of the Epidemiology Section of the Epidemiology and Prevention Branch, Division of Public Health, Department of Human Resources

May 1997

Volume 13 Number 5
HBsAg Screening Among Pregnant Women Who Use Medicaid to Pay for Delivery

http://www.ph.dhr.state.ga.us
Division Of Public Health
Patrick J. Meehan, M.D. - Director Epidemiology and Prevention Branch State Epidemiologist
Kathleen E. Toomey, M.D., M.P.H.- Director Epidemiology Section Paul A. Blake, M.D., M.P.H.-Chief
Notifiable Diseases
Jeffrey D. Berschling, M.P.H.; Karen R. Horvat, M.P.H. ; Amri B. Johnson, M.P.H.; Jane E. Koehler, D.V.M, M.P.H.; Katherine GibbsMcCombs, M.P.H.; Preeti Pathela, M.P.H.; Sabrina Walton, M.S.P.H.
Chronic Disease
Nancy E. Stroup, Ph.D.-Program Manager Patricia M. Fox, M.P.H.; A. Rana Bayakly, M.P.H.; Edward E. Pledger, M.P.A.
Tuberculosis
Naomi Bock, M.D., M.S.
HIV/AIDS/Sexually Transmitted Diseases
Kim Cook, M.D., M.S.P.H.-Program Manager Stephanie Bock, M.P.H.; Mary Lynn Gaffield, M.P.H.; Andrew Margolis, M.P.H.
Perinatal Epidemiology
Mary D. Brantley, M.P.H.; Paul C. Gangarosa, M.P.H.; Raymond E. Gangarosa, M.D., M.P.H.; Leslie E. Lipscomb, M.P.H.; Mary P. Mathis, Ph.D., M.P.H.
Preventive Medicine Resident
Hussain R. Yusuf, M.B.B.S., M.P.H.
EIS Officer
Michael S. Friedman, M.D.
Georgia Epidemiology Report Editorial Board
Editorial Executive Committee Paul A. Blake, M.D., M.P.H.- Editor Kathleen E. Toomey, M.D., M.P.H. Mary D. Brantley, M.P.H. Jeffrey D. Berschling, M.P.H.
Mailing List Edward E. Pledger, M.P.A.

An estimated 22,000 infants are born each year in the U.S. to mothers who are chronic hepatitis B carriers.1
Approximately 600 infants are born to hepatitis B carrier mothers each year in Georgia; as many as 162 of these infants will become chronic carriers themselves, and an estimated 40 infants will die of hepatocellular carcinoma or chronic liver disease later in life.2
The Advisory Committee on Immunization Practices (ACIP), the American College of Obstetrics and Gynecology, the American Academy of Pediatrics, and the American Academy of Family Practice currently recommend hepatitis B surface antigen (HBsAg) testing of all pregnant women and administration of immunoprophylaxis to infants of HBsAg positive mothers. No systematic evaluation of this policy currently exists for Georgia. This study was carried out to determine the rate of HBsAg screening among pregnant women in Georgia who used Medicaid to pay for obstetric services between 1991 and 1994. We also assessed if the proportion of women tested for HBsAg varied between health districts and with respect to whether or not the woman received Georgia Medicaid Program's Perinatal Case Management (PCM) services. The PCM is a care coordination program that was launched in 1990 to increase access to prenatal care and improve pregnancy outcomes.
Methods
The Georgia Medicaid Claims files for the years 1991-1994 were used to identify women aged 10-55 years for whom Medicaid paid for delivery. The prenatal claims history for these women for 300 days before delivery was identified and whether the woman had received the PCM was also established. Women were defined to have been screened for HBsAg if they had a claim for the

Epidemiology Section, Epidemiology & Prevention Branch, Two Peachtree St., N.W., Atlanta, GA 30303-3186

Phone: (404) 657-2588

FAX: (404) 657-2586

Obstetric Panel (CPT code 80055) or the HBsAg test (CPT code 86287). The proportion of women tested for HBsAg was determined for the state as well as by PCM status, health district, race/ethnicity, and age. The p-value from chi-square test was used to assess significance of differences in percents of women screened.
Results
The number of women for whom Medicaid paid for delivery between 1991 and 1994 ranged from 52,230 to 58,772. During this period, the proportion of Medicaid women who received PCM increased from 12% to 40%. The percentage of Medicaid women who were screened for HBsAg each year from 1991 to 1994 were 33.8%, 43.8%, 54.7%, and 61.8% respectively. Between 1991 and 1994, the HBsAg screening rate among women who received PCM increased from 36% to 70% whereas the screening rate among non-PCM women increased from 34% to 56% (Figure 1). The differences in screening rates between PCM and non-PCM women were significant for each year.
Figure 1. Percent of Medicaid Women Screened for Hepatitis B

Table 1. Hepatitis B Screening Rates for Medicaid Women Who Received Perinatal
Case Management (PCM) and Those Who Did Not, by Health Districts

% Tested for HBsAg >80% 70% - 79%
60% - 69%

Health District

PCM

Non-PCM

Cobb Clayton Gwinnett

(Georgia) Fulton Dekalb Dublin Augusta
Valdosta Albany Brunswick

Rome Dalton Macon Columbus Athens

Cobb Clayton Gwinnett Valdosta Albany Savannah

% Tested

50% - 59%

Gainesville Lagrange Waycross

(Georgia) Gainesville
Dekalb Lagrange
Dublin Macon Augusta Columbus Brunswick

Among the Medicaid women who delivered in 1994, the proportion tested for HBsAg varied by health district, with Dublin, Albany, and Gwinnett districts having overall screening rates greater than 73%. Among non-PCM women, the rate of screening was less than 50% in Rome, Dalton, Fulton, Waycross, and Athens (Table 1). Fifty percent of the Medicaid women who delivered in 1994 were black and 44% were white. The race or ethnicity was other or unknown for 6% of the women, and 13% were 30 or more years old. Although the rates of HBsAg screening among blacks and whites were similar (62.8% vs. 61.9%), it was lower (54.7%) among those who were of other or unknown race or ethnicity. A significantly lower percent of women who were 30 or more years old were screened than women who were less than 30 years old (52.2% vs. 63.4%).

<50%

Savannah

Rome Dalton Fulton Waycross Athens

Discussion
Infants born to hepatitis B carrier mothers have a 10%-90% chance of acquiring HBV infection depending on their mother's hepatitis B envelope antigen status.1 However, 85%-95% of these infections can be prevented by identifying pregnant women who are HBsAg positive and administering appropriate immunoprophylaxis to their infants.3 Recommendations for universal HBsAg screening of pregnant women were based on the fact that selective screening of high risk women failed to identify at least 50% of women who were HBsAg positive.1

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The findings of this study indicate that although HBsAg screening of pregnant women in Georgia who used Medicaid to pay for obstetric services has increased considerably from 1991 to 1994, further efforts are needed to ensure that all such women are tested for HBsAg. Compared to women who did not receive PCM, a significantly greater proportion of women who received PCM were tested for HBsAg. In addition, the screening rate among women with PCM increased more rapidly than among women without PCM. These facts suggest both that the PCM initiative is effective in improving prenatal care with respect to hepatitis B screening, and additional attention needs to be focused toward increasing prenatal HBsAg screening among non-PCM women. However, it should be noted our analysis did not control for any confounding factors that may have increased the screening rate among women receiving PCM.
Health districts with the highest HBsAg screening rates were located around metropolitan Atlanta and in south Georgia. By 1994, nine of the 19 health districts had overall HBsAg screening rates below 60% and in 5 districts the screening rates among women without PCM were less than 50%. Compared to whites and blacks, the rate of screening was lower among those who were of other or unknown race. This latter group includes women who may have been born in regions of the world where HBV is highly endemic, such as southeast Asia and Africa1, and therefore are more likely to be HBsAg positive. It is not clear why the screening rate was lower among women who were 30 or more years old than among women less than 30 years old.
To our knowledge this is the first study to use Medicaid claims data to monitor HBsAg screening of pregnant women. Medicaid claims files offer an existing source of data that can be used to assess health care utilization and needs of the population that use Medicaid to pay for services. The rate of screening found in this study is lower than that reported by a national survey where 84% of all pregnant women were tested for HBsAg.4 A study carried out in two counties of Georgia found 80% to 89% women were tested for HBsAg between 1990 and 1992 and the rates were similar for Medicaid and non-Medicaid women (Centers for Disease Control and Prevention, Atlanta, GA, 1994, unpublished data). The discrepancy between these maternal HBsAg screening rates and the rates determined by the present study is probably due to the fact that Medicaid claims files are instruments used for reimbursement of services and were not developed for monitoring screening rates.
We have identified 3 limitations to this study which may lead to underestimation of screening rates. First, we analyzed data from the first 5 of the 28 details (billing for a specific procedure or test) contained in each Medicaid claim because for most claims, only the first five details had infor-

mation. We estimate that if information from all details were analyzed, the screening rate would have increased by approximately 5% (data not shown). Second, this study does not include women using Medicaid who were screened by public health departments which did not file any claim for the test. Third, for some women using Medicaid to pay for delivery services, an HBsAg test may have been done without filing a Medicaid claim for reimbursement.
For HBsAg screening to be effective in preventing perinatal transmission of HBV, infants born to HBsAg positive mothers need to be administered hepatitis B immune globulin and hepatitis B virus vaccine. This study was not designed to identify HBsAg positive women or follow-up their infants to ascertain administration of immunoprophylaxis.
Conclusions
Our findings indicate that efforts are needed to further increase the rate of HBsAg testing among women using Medicaid to pay for delivery in Georgia, especially among women who do not receive perinatal case management. We lack information on reasons for the striking geographic variation in screening rates, and recommend that barriers to adequate screening be evaluated. Medicaid claims files offer an alternative means for monitoring HBsAg screening among Medicaid clients and are useful for assessing trends and group-specific differences in screening rates.
References
1. Shapiro CN, Margolis HS. Impact of hepatitis B virus infection on women and children. Pediatric Infections. 1992;6:75-96.
2. Estimates for Georgia based on extrapolation from national estimates and supported by prevalence of hepatitis B carrier state among select groups of pregnant women in Georgia as reported by - Piper JM, Maier RC. Prenatal hepatitis B testing in a mid-size southern city. Southern Medical Journal. 1991;84:727-729; Nui MT, Paul VT, Stoll BJ, Albert GP, Margolis HS. Prevention of perinatal transmission of hepatitis B virus. AJDC. 1992;146:793-796;
3. Centers for Disease Control and Prevention. Hepatitis B virus: a comprehensive strategy for eliminating transmission in the United States through universal childhood vaccination; recommendations of the Immunization Practices Advisory Committee (ACIP).MMWR.1991;40(RR-13):1-19.
4. Yusuf HR, Mahoney FJ, Shapiro CN, Mast EE, Polish L. Hospital-based evaluation of programs to prevent perinatal hepatitis B virus transmission. Arch Pediatr Adolesc Med. 1996;150:593-597.
This report was prepared byEd Tierney MPH, Hussain Yusuf MBBS, MPH, Roger Rochat, M.D., Steve Einbender, Peggy Monkus, Michael Chaney. Epidemiology and Prevention Branch and Family Health Branch, Georgia Division of Public Health.

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The Georgia Epidemiology Report Epidemiology and Prevention Branch Two Peachtree St., NW Atlanta, GA 30303-3186

May 1997

Volume 13 Number 5

Reported Cases of Selected Notifiable Diseases in Georgia Profile* for February 1997

Selected Notifiable Diseases Campylobacteriosis

Total Reported for February
1997 43

Previous 3 Months Total

Ending in February

1995

1996

1997

182

138

117

Previous 12 Months Total

Ending in February

1995

1996

1997

770

1013

778

Chlamydia genital infection Cryptosporidiosis

1258 4

1605 0

3379 7

2879 11

1605 0

12116 7

13393 92

E. coli O157:H7

3

1

3

14

3

30

50

Giardiasis Gonorrhea Haemophilis influenzae (invasive)

77 1527
7

80 3596
11

122 6115
15

208 4255
20

311 3596
20

597 21729
40

878 18982
53

Hepatitis A (acute)

42

21

34

95

31

96

449

Hepatitis B (acute)

12

Blood Lead Level > 10 g/dL (cap)

147

Blood Lead Level > 10 g/dL (ven)

53

Legionellosis

0

Lyme Disease

0

Meningococcal Disease (invasive)

8

34

6

20

318

550

425

68

126

160

8

1

0

0

0

1

32

50

27

77

75

74

318

3008

2920

68

639

649

17

11

3

2

14

2

43

116

133

Mumps

0

2

2

3

2

10

10

Pertussis Rubella

4

4

7

7

12

30

36

0

0

0

0

0

0

0

Salmonellosis

70

236

308

299

1088

1710

1434

Shigellosis Syphilis - Primary Syphilis - Secondary

94

406

105

300

1520

1196

1202

14

55

62

45

182

290

188

36

127

148

109

483

651

466

Syphilis - Early Latent

83

417

362

282

1558

1635

1263

Syphilis - Other** Syphilis - Congenital

111

227

247

319

711

1152

1012

6

10

21

8

33

66

28

Tuberculosis

45

242

204

182

762

769

760

* The cumulative numbers in the above table reflect the date the disease was first diagnosed rather than the date the report was received at the state office; and therefore are subject to change over time due to late reporting. The 3 month delay in the disease profile for a given month is designed to minimize any changes that may occur. This method of summarizing data is expected to provide a better overall measure of disease trends and patterns in Georgia.

** Other syphilis includes latent (unknown duration), late latent, late with symptomatic manifestations, and neurosyphilis.

Report Period

Total Cases Reported *

AIDS Profile Update

Percent

Risk Group Distribution (%)

Race Distribution (%)

Female

MSM IDU MSM&IDU HS Blood Unknown White Black Other

Last 12 Mos 05/96 to 04/97 5 Yrs Ago 05/91 to 04/92 Cumulative 01/80 to 04/97

2206 1896 17659

20.3

40.8 17.9

4.9

13.9

53.1 23.1

7.7

14.6

52.0 19.0

6.0

16.1 1.2

19.1

9.7 1.5

4.7

11.2 2.0

9.8

28.4 69.1 2.5 40.1 58.0 1.9 40.3 57.7 2.0

MSM - Men having sex with men IDU - Injection drug users HS - Heterosexual * Case totals are accumulated by date of report to the Epidemiology Section

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