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Effect of family history on disclosure patterns of cystic fibrosis carrier status.

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American Journal of Medical Genetics Part C (Semin. Med. Genet.) 119C:70 – 77 (2003)
A R T I C L E
Effect of Family History on Disclosure Patterns
of Cystic Fibrosis Carrier Status
KELLY E. ORMOND,* PATTI L. MILLS, LUCILLE A. LESTER, AND LAINIE F. ROSS
As general population screening becomes more common, an increasing number of cystic fibrosis (CF) carriers will be
identified who do not have a family history of CF. Whether these carriers inform their relatives of their carrier status and
whether their relatives are motivated to pursue carrier screening is unknown. We surveyed CF carriers with and
without a family history of CF to understand whether and how information dissemination patterns differ, why
information is or is not shared, and to what extent relatives are known to undergo testing. CF carriers were identified
from a general population carrier screening clinic (group B ¼ 18) or were parents of affected children followed at a CF
clinic (group A ¼ 30). CF carriers with a family history told essentially 100% of their living parents, siblings, and halfsiblings, while those without a family history told 84% of living parents and 56% of siblings (P < 0.05). Despite the
high rate of information dissemination in both groups, few siblings were known to have undergone carrier screening
(14/74). Significantly fewer second- and third-degree relatives were informed about carrier status or were known to
have undergone carrier screening. Group A was more likely to inform second- and third-degree relatives about carrier
status. Our study documents that the frequency and reasons for disclosing CF carrier status differ between individuals
with and without a family history of CF despite the fact that the reproductive risks for their relatives are the same.
ß 2003 Wiley-Liss, Inc.
KEY WORDS: cystic fibrosis; disclosure; genetic screening; prenatal screening; mass screening; family relations; obligate carrier; carrier
testing; heterozygote; heterozygote detection
INTRODUCTION
Historically, most reproductive genetic
risk counseling for cystic fibrosis (CF)
was offered based on family history. In
the early 1990s, CF mutation analysis
became available to individuals with a
family history, and since the late 1990s,
Kelly E. Ormond, MS, is an Assistant in the
Department of Obstetrics and Gynecology,
Section of Reproductive Genetics, at Northwestern University, as well as a fellow at the
MacLean Center for Medical Ethics at the
University of Chicago, both in Chicago,
Illinois.
Patti L. Mills, MS, is a genetic counselor in
the Department of Human Genetics at the
University of Chicago in Chicago, Illinois.
Lucille A. Lester, M.D., is a Professor in
the Department of Pediatrics at Rush Presbyterian St. Lukes Medical Center in Chicago,
Illinois.
Lainie F. Ross, M.D., Ph.D., is an Associate
Professor in the Department of Pediatrics
and Assistant Director of the MacLean
Center for Medical Ethics, both at the
University of Chicago in Chicago, Illinois.
*Correspondence to: Kelly E. Ormond, 76
N. Sr. Cair #1280, Chicago, IL 60611.
E-mail: K-ormond@northwestern.edu
DOI 10.1002/ajmg.c.10008
ß 2003 Wiley-Liss, Inc.
genetic carrier testing has been available
to a wider population. In 1997, a
National Institutes of Health (NIH)
consensus statement recommended offering CF carrier screening to Caucasian
individuals of reproductive age regardless of family history [National Institutes
of Health, 1997]. In 2001, the American
College of Obstetrics and Gynecology
(ACOG) and the American College of
Medical Genetics (ACMG) jointly issued a similar recommendation [American
College of Obstetrics and Gynecology
and American College of Medical
Genetics, 2001; Grody et al., 2001].
One of the main barriers to carrier testing is lack of public awareness
about CF and what CF carrier testing
One of the main barriers
to carrier testing is lack of
public awareness about CF
and what CF carrier testing
can and cannot do.
can and cannot do. While the consensus
statements seek to detect CF carriers
in the general population, first- and
second-degree relatives of those already
known to be CF carriers are themselves
at higher risk of being carriers. In order
to counsel these patients accurately
about their risk of being a CF carrier,
they must be aware of their relative’s CF
carrier status and inform the clinician
of this information. Barriers to information dissemination include lack of
information about CF [Suhr et al., 1994;
Fanos and Johnson, 1995a]; the perception that relatives would not be interested in carrier screening [Suhr et al.,
1994; Sorenson et al., 1996; Williams
and Schutte, 1997]; and gender (studies
show that men are less likely than
women to inform family members of
their genetic risks [Callanan et al., 1995;
Fanos and Johnson, 1995a]).
Even when individuals know that
they are at increased risk for carrying a
genetic abnormality, many choose not to
undergo testing. In studies that assess
individuals at risk for carrying a disease
mutation or a balanced chromosome
translocation based on family history,
ARTICLE
testing uptake has been low [Ayme et al.,
1993; Suhr et al., 1994], and first-degree
relatives are significantly more likely to
undergo carrier testing than more distant (second- and third-degree) relatives
[Suslak et al., 1985]. Studies that specifically addressed the interest in and
acceptance of CF screening in individuals with a family history of CF
[Callanan et al., 1995; Sorenson et al.,
1997; Henneman et al., 2001] and in
nonpregnant individuals in the general
population [Clayton et al., 1996] demonstrate significantly lower screening
uptake by individuals without a family
history of CF. Awareness of and personal
Studies that specifically
addressed the interest in and
acceptance of CF screening
in individuals with a family
history of CF and in
nonpregnant individuals
in the general population
demonstrate significantly
lower screening uptake by
individuals without a
family history of CF.
experience with CF has been associated
with both increased [Sorenson et al.,
1997; Wake et al., 1997] and decreased
[Botkin and Alemagno, 1992] uptake of
carrier screening, suggesting that the
perceived burden of CF may play a role
in whether testing is pursued [Fanos
and Johnson, 1995b]. There may also be
logistical barriers to uptake of testing
such as cost, accessibility to facilities
offering testing, the desire to avoid phlebotomy, and family myths about who is
at risk for carrying a disease mutation
[Suhr et al., 1994; Fanos and Johnson,
1995b; Clayton et al., 1996; Sorenson
et al., 1997].
Given the current NIH, ACMG,
and ACOG recommendations, more
CF carriers without a family history
are likely to be detected. Our study
addresses whether the presence of a
AMERICAN JOURNAL OF MEDICAL GENETICS (SEMIN. MED. GENET.)
family history of CF affects carrier status
information dissemination patterns and
the uptake of carrier testing in at-risk
relatives; and which factors facilitate or
hinder information dissemination.
MATERIALS AND METHODS
Subject Recruitment
Group A consisted of obligate carriers
identified through a CF clinic population at Rush Presbyterian St. Lukes
Medical Center (Rush/St. Lukes) in
Chicago; both mothers and fathers of
children 2–10 years in age with CF were
recruited. Since most patients are diagnosed in the first year of life, the lower
limit of 2 years was chosen to ensure that
parents had sufficient opportunity to
disclose CF carrier information to their
relatives. The upper limit of 10 years was
chosen because it is only within the last
10 years that genetic testing has been
available and routinely offered to families
in the context of a new diagnosis of CF
in a family member. Fifty families were
included in this study population, and
assuming intact families, questionnaires
were mailed for both parents to complete individually. These families had
been counseled about the reproductive
risks to themselves and their relatives by a
pulmonologist (L.A.L.) or by a genetic
counselor associated with the CF clinic.
Group B consisted of CF carriers
identified through general population
screening at Northwestern Memorial
Hospital (NMH) in Chicago between
January 1998 and August 2000. During
that time, NMH offered CF screening to
all Caucasian prenatal patients seen for
genetic counseling (e.g., preprocedure
amniocentesis/CVS counseling); to all
patients requesting CF screening; and
to individuals of Ashkenazi Jewish (AJ)
ancestry as part of a broader panel of
screening tests. All patients seen for
carrier screening received a short genetic
counseling session (by K.E.O. or another
genetic counselor) prior to screening
and a follow-up letter with their results.
Those determined to be carriers were
also counseled about the reproductive
risks to themselves and to relatives and
received a generic letter to share with
71
family members regarding their carrier
risk and the availability of screening.
Between January 1998 and August
2000, approximately 350 individuals
were screened for CF and 850 were
screened for the AJ panel. Inclusion
criteria for this study included individuals who were found to be CF carriers
greater than 6 months prior to the
beginning of the study period. Fiftyone individuals, including two at risk
couples (neither of the women was
pregnant at the time of our study) and
seven individuals with a family history
of CF carriers but no affected relatives
met the study criteria. Subjects in both
groups were limited to English-speaking
adults over 18 years old.
Questionnaire
All participants were asked to complete
a written survey, which consisted of
questions about demographic information and questions to ascertain the total
number of first-, second-, and thirddegree relatives, their maternal/paternal
relationships to the study subject, and
their relatives’ gender; whether or
not study subjects informed their
first-, second-, and third-degree relatives
about their own carrier status; the rate
at which they did so (e.g., the time
period that passed between the subjects
learning of their own carrier status and
informing their relatives); and their
awareness of whether the informed
relatives sought testing. In order to assess
the reasons for disclosing carrier status
and barriers to information dissemination, subjects were asked either to select
from a list of reasons for sharing or
not sharing carrier status information
(Table I) or to describe their reasons in
their own words. Approximately onethird to half of the participants provided unlisted reasons, which were coded
to correspond to listed reasons; new
categories were created for unlisted
reasons.
The questionnaire was mailed in
February 2001 and remailed to nonresponders 1 month later. A third mailing was sent to families in group A if
neither parent had responded by June
2001. Institutional review boards at all
72
AMERICAN JOURNAL OF MEDICAL GENETICS (SEMIN. MED. GENET.)
ARTICLE
TABLE I. Possible Factors Involved in Disclosing CF Carrier Status to Relatives
The age of the relative
The relative’s level of maturity or ability to understand the information and its implications
The relative’s gender
Whether or not the relative lives nearby or if you talk frequently
Your social relationship with that relative (whether or not you are comfortable having personal conversations with the relative)
Concerns about privacy
Concerns about financial discrimination (related to insurability, employability)
Your own feelings about being a carrier
Your feelings about the severity of CF
Whether or not you thought it would be helpful for you to talk about your CF carrier status (i.e., to help you cope or sort out your own
feelings about being a carrier)
Concern about what the relative might think of you
Concern about causing a relative anxiety or stress about his/her own health or carrier status
Concern about causing a relative anxiety or stress about his/her own chance of having an affected child
Concern that the relative or his/her child(ren) could have an affected baby
Your beliefs about prenatal testing and/or pregnancy termination
Your relatives’ beliefs about prenatal testing and/or pregnancy termination
Recommendations from your/your child’s doctor or genetic counselor
Recommendations from your social support network (e.g., close friends or family members, spiritual/religious advisors)
Medical issues related to a child affected with CFa
Forgot or did not think of ita
Someone else (e.g., parent) disseminated relevant informationa
a
Categories created to incorporate responses subjects provided in their own words.
three participating institutions approved
the study design as described.
Analysis
SPSS 10 was used to perform descriptive
statistics, independent t-tests, one-way
ANOVA, and Pearson chi-square values
as appropriate; values greater than
P ¼ 0.05 were considered significant.
Because disclosure to relatives did not
vary significantly by the subjects’ or
relatives’ gender, the categories of familial relationships were combined (e.g.,
sisters and brothers were recorded as
siblings) to provide more power to the
analyses. Carrier information dissemination patterns between groups A and B
were compared. Based on previous
literature, age, gender, experience with
CF, and perceived severity of CF were
considered as potentially confounding
factors in the analysis.
RESULTS
Thirty-five surveys were returned from
group A (parents of children with CF),
with five responses excluded because
either a parent (n ¼ 2) or the affected
child (n ¼ 2) was adopted, or because
the survey was not adequately completed (n ¼ 1). The total response rate
was 30/95 (33%). For group B, 51 surveys were sent, but 3 surveys were
returned as undeliverable. Of the
remaining 48, 18 were returned (38%).
Therefore, a total of 48 valid surveys
make up the study data: 30 from group
A (family history of an individual
affected with CF) and 18 from group B
(no family history of an individual
affected with CF).
Subject demographics are reported
in Table II. There were no significant
differences between the two groups with
regards to age, gender, or percent in a
married or committed relationship.
There were, however, significant differences between the groups with regards
to educational level and religious affiliation. With regards to education, 85% of
the overall population had at least a
college education, with fewer in group
A reporting college education or higher
(t-test, P ¼ 0.001). Religious affiliation
was notable for a high percentage of
group B reporting Jewish affiliation
(65%), while group A was almost exclusively of Christian affiliation, with no
respondents of Jewish descent.
Consistent with our study design,
100% of group A reported knowing
someone affected with CF; somewhat
surprisingly, no individual in the general
population screening group knew anyone with CF (chi-square, P < 0.001).
On a Likert scale of 1 (not severe) to
4 (severe), 48% of respondents stated
that CF was severe, 30% moderate, 18%
mild, and 2% not severe. There were
significant differences between groups
such that all individuals in group B
(who did not know an individual with
CF) ranked CF as moderate to severe
(mean, 3.71), while individuals in group
A, with a family history of CF, reported a broader range of perceived severity (mean, 3.00; ANOVA, P ¼ 0.004).
Because of the direct association between group affiliation and knowledge
of a person affected with CF, it was
impossible to determine whether the
family history or overall knowledge of
ARTICLE
AMERICAN JOURNAL OF MEDICAL GENETICS (SEMIN. MED. GENET.)
73
TABLE II. Subject Characteristics
Age
Gender (% female)
Marital status, (% married/in a committed relationship)
Educational level (% with college or postgraduate education)a
% who knew someone with CFa
Average perceived severity CF (1, not severe; 4, severe)a
% who would consider prenatal diagnosis for CF
a
Group A, family
history (n ¼ 30)
Group B, no family
history (n ¼ 18)
Total population
(n ¼ 48)
38.27
63%
94%
74%
100%
3.0
50%
35.5
66%
100%
100%
0%
3.71
100%
37.42
65%
92%
85%
60%
3.27
70%
P < 0.05.
CF was the major factor underlying the
difference in perceived sev erity of CF.
Seventy percent of respondents
stated they would consider prenatal
diagnosis for CF; 6% stated they were
against it; 14% stated that testing should
be available, although they would not
undergo testing themselves; 8% were
undecided about prenatal diagnosis for
CF; and 2% had not thought about
it. There were significant differences
between groups, with 100% of the general population screening group stating
that they would consider prenatal diagnosis for CF, versus approximately 50% of
the obligate carrier group (P ¼ 0.004).
Frequency and Rate of
Dissemination of CF Carrier
Status Information to Relatives
and Awareness of Relatives’
Decisions to Undergo Testing
Living relatives of study participants included a total of 287 first-degree relatives
(71 parents, 110 siblings, 12 half-siblings,
94 children), 186 second-degree relatives, and 529 third-degree relatives.
Table III lists the percentage of relatives
in each category who were informed
about carrier status. Across all subject
groups and categories of relatives, the
gender of the CF carrier or the relatives
did not impact information dissemination patterns or uptake of carrier screening in relatives, and therefore several of
the gender-related categories were combined to add power to statistical analyses.
CF carriers with a family history
told virtually 100% of their living parents,
siblings, and half-siblings, while carriers
with no family history told 84% of living parents and 56% of siblings. Fathers
CF carriers with a family
history told 100% of their
living parents, siblings, and
half-siblings, while carriers
with no family history told
84% of living parents
and 56% of siblings.
(t-test, P ¼ 0.05), full sisters (P ¼ 0.045),
and full brothers (P ¼ 0.004) were informed more quickly by carriers who
had an affected child. Regardless of the
high frequency of information dissemination in both groups, few siblings were
known to have undergone carrier
screening (14/122; 11.5%). One-third
of children at risk for being carriers
reportedly had been informed of their
parent’s carrier status. For all children
not informed of their CF carrier risk, the
primary reason was age; presumably
their parents felt they were too young
to understand the significance of the
information.
TABLE III. Disclosure of Carrier Status to Living Relatives
% informed
Relative
a
Parents
Full siblingsa
Half-siblings
Maternal aunts/uncleb
Paternal aunts/unclesc
Total aunts/unclesc
Maternal cousinsc
Paternal cousinsc
Total cousinsc
a
Group A, family history
d
45/46 (98%)
78/78 (100%)
11/12 (92%)
55/71 (78%)
43/73 (58%)
98/144 (68%)
110/200 (55%)
99/218 (45%)
209/418 (50%)
Group B, no family history
21/25 (84%)
18/32 (56%)
N/A
6/19 (32%)
3/23 (13%)
9/42 (21%)
1/37 (3%)e
2/74 (3%)e
3/111 (3%)e
P < 0.05.
P < 0.01.
c
P < 0.001.
d
One individual was adopted out of the family and has had little contact with his/her
biological father.
e
Several respondents did not list a number of cousins, but simply stated ‘‘too many’’;
therefore, these numbers are possibly an overestimation of the percentage of informed
cousins.
b
74
AMERICAN JOURNAL OF MEDICAL GENETICS (SEMIN. MED. GENET.)
There were significant differences
between groups A and B in the frequency of informing second-degree
relatives (68% vs. 21%, respectively;
chi-square, P < 0.001) and third-degree
relatives (50% vs. 3%; P < 0.001) about
carrier status. When potential confounding variables were considered,
including education, gender, perceived
severity of CF, and interest in prenatal
diagnosis, only education was a significant factor in dissemination of carrier status to both second- (ANOVA,
P ¼ 0.001) and third-degree relatives
(P < 0.001).
For second-degree relatives, slightly
more maternal relatives than paternal
relatives were informed (58% vs. 47%);
no such differences were noted for
third-degree relatives. In general, carriers told either everyone or no one in a
family segment (e.g., all maternal aunts/
uncles/cousins were told, but no paternal relatives were told). Information was
provided more slowly to more genetically distant relatives such as thirddegree relatives (e.g., an increase in
the time between diagnosis and disclosure; Table IV). For both groups, few
second-degree (6/186, or 3.2%) and
third-degree relatives (13/539, or 2.4%)
ARTICLE
were known to have undergone carrier
screening.
Reasons for Disclosing CF
Carrier Status
Participants did or did not disclose
CF carrier status for a number of reasons. Individuals provided between
0–7 reasons for disclosure and 0–2 responses for nondisclosure. The most
common reason for disclosing information was a close social relationship
with the relative, as well as the need
for social support in a time of crisis
(whether in the context of the diagnosis
of an affected child or the stressful situation of dealing with newly discovered
carrier status in the midst of pregnancy).
The most common reason
for disclosing information
was a close social relationship
with the relative, as well
as the need for social support
in a time of crisis.
TABLE IV. Time to Disseminate Carrier Status
Disclosure to whom
(n ¼ total no. informed)a
Mother (n ¼ 37)
Father (n ¼ 29)
Full sisters (n ¼ 32)
Full brothers (n ¼ 25)
Half-siblings (n ¼ 11)
Maternal aunts (n ¼ 32)
Maternal uncles (n ¼ 24)
Paternal aunts (n ¼ 25)
Paternal uncles (n ¼ 17)
Maternal female cousins (n ¼ 43)
Maternal male cousins (n ¼ 56)
Paternal female cousins (n ¼ 45)
Paternal male cousins (n ¼ 59)
a
Time between diagnosis and disclosure
As soon as possible % <6 months
97%
94%
97%
92%
100%
69%
66%
69%
50%
70%
62%
67%
71%
3%
3%
3%
8%
31%
33%
25%
40%
24%
31%
20%
21%
% >6 months
3%
6%
10%
6%
6%
13%
7%
Numbers may slightly underestimate numbers of individuals informed during each time
segment, as some respondents did not specify the number of relatives informed during the
time period.
Responses such as ‘‘I am very close to all
four of my siblings. I told them for many
reasons. One being that I needed their
support’’; ‘‘We are a really close family;
everyone was told’’; and ‘‘We were
close—I did not hesitate’’ suggest that
social closeness with relatives was a
common reason for disclosing results
across all relative categories. Rarely,
social and/or geographical distance was
cited as a reason for not disclosing carrier
status: ‘‘It’s just that I haven’t spoken to
some of them recently; however, I’ll
probably share it with them when I do
talk with them.’’
Slightly fewer relatives articulated
their relatives’ reproductive risks as a
reason for disclosing CF carrier status:
‘‘They should know for their future
children’s health’’ and ‘‘If they were
going to have children please get tested’’
(from an obligate carrier). In other instances, carriers used relatives’ unmarried
status or completion of childbearing as
a reason for nondisclosure: ‘‘My brother
is not married and does not have a significant girlfriend. . . . Perhaps I should tell
him; he too could be a carrier’’ and ‘‘[My
relatives are] done having children.’’
Another major reason for disclosure
of CF carrier status to relatives was
secondary to the disclosure of the child’s
ongoing health problems related to CF:
‘‘At the time we told our relatives, we
really were not thinking of anything
other than our newborn’s health’’ and
‘‘It was discussed when they were told
my son has CF.’’
In general, reasons for nondisclosure were less frequently given and were
related to lack of social closeness with the
relatives. No individuals cited negative
feelings about being a CF carrier (e.g.,
guilt, shame) or fear of causing anxiety in
relatives as reasons for nondisclosure.
DISCUSSION
There are numerous reasons why some
carriers of genetic abnormalities do
not share carrier information: altered
self-concept [McConkie Rosell and
DeVellis, 2000], misunderstanding of
genetic risk, the perception that their
relatives would not be interested in
undergoing genetic testing [Surh et al.,
ARTICLE
1994; Sorenseon et al., 1996], or because
of their own personal feelings about
disease severity and/or about the use of
testing and prenatal diagnosis. Studies
There are numerous reasons
why some carriers of genetic
abnormalities do not share
carrier information: altered
self-concept, misunderstanding
of genetic risk, the perception
that their relatives would
not be interested in the
information, or because of
their own personal feelings
about disease severity and/or
about the use of testing
and prenatal diagnosis.
that address the psychosocial aspects of
carrier status focus primarily on selfconcept and do not necessarily measure
how disclosing carrier status impacts
family dynamics. It is likely that such
disclosures alter family relationships in
both positive and negative ways, which
also may vary depending on the mode of
inheritance (e.g., autosomal recessive vs.
sex-linked vs. translocations).
Our study indicates that in both
groups CF carriers are more likely to
share information about their carrier
status with those relatives who are more
closely related genetically and with
those relatives with whom there is a
close social bond; CF carriers favor telling one side of the family (more often
the maternal relatives than paternal ones)
of their status, suggesting personal or
social factors play a greater role in motivating carriers to share their status than
genetic factors; and disclosure of carrier
status usually occurs within 6 months of
receiving the diagnosis of being a carrier,
often in the context of explaining an
affected child’s condition or as a means of
soliciting social support. Individuals
with a family history of CF (e.g., an
affected child) are more likely to share
AMERICAN JOURNAL OF MEDICAL GENETICS (SEMIN. MED. GENET.)
carrier status with relatives of all degrees,
primarily because they are sharing other
health information about their child.
Even if one assumes some selection
bias, i.e., those individuals returning
questionnaires were more comfortable
with sharing their carrier status, it is clear
from our study that the presence of an
affected family member significantly
influences the disclosure pattern of CF
carrier status within the family. Yet the
method of identifying CF carrier status
does not impact the risk assessment;
relatives of CF carriers, whether identified via general population screening or
due to a positive family history, have the
same risks (e.g., a third-degree relative to
a CF carrier has a one-in-sight chance of
also being a carrier, regardless of whether
there is an affected individual in the
family). While this may become less
significant as CF carrier screening becomes routine in the prenatal setting, it
does prevent fully informed decisionmaking for those who do not seek
counseling or testing prior to conception. Thus, without knowledge of a
family history, individuals may be less
likely to undergo counseling or carrier
testing themselves because they do not
view themselves at increased risk when
in fact they are.
One possible explanation for the
difference in disclosure frequencies
between those with and those without
family history of an affected family
member is the impact of personal
experience with CF. The literature of
One possible explanation
for the difference in disclosure
frequencies between those with
and those without family
history of an affected family
member is the impact of
personal experience with CF.
disability studies supports the concept
that personal experience with a disorder
(e.g., CF) is related to more positive
attitudes toward disability [Yuker, 1994],
75
which is consistent with our study data
regarding perceived severity of CF and
the influence of personal experience.
And yet, although carriers without
exposure to CF report higher perceived
severity rankings, such that one might
expect that they would be more motivated to share information about reproductive risks, they were less likely to
disclose. An alternate hypothesis to
explain this lower disclosure rate is that
nondisclosers perceive a decreased sense
of the reality of risk. Many individuals
who have never experienced the occurrence of an affected child in the family
may perceive it to be unlikely that the
event could ever happen, regardless of
how they perceive severity, while individuals with personal experience may feel
an increased awareness of vulnerability
[Livneh, 1982].
An alternate hypothesis to
explain this lower disclosure
rate is that nondisclosers
perceive a decreased sense of
the reality of risk. Many
individuals who have never
experienced the occurrence
of an affected child in the
family may perceive it to be
unlikely that the event could
ever happen, regardless of
how they perceive severity,
while individuals with
personal experience may
feel an increased awareness
of vulnerability.
A second possible explanation for
the difference in disclosure frequencies
may be that many obligate carriers did
most of their telling in the context of
explaining their child’s diagnosis, making carrier status an inadvertent disclosure, rather than the primary one. This
mode of disclosure may be useful to
some relatives, but it assumes an under-
76
AMERICAN JOURNAL OF MEDICAL GENETICS (SEMIN. MED. GENET.)
standing of the complexities of recessive
inheritance, that relatives can determine that they are at risk, and that
relatives are aware of genetic screening
availability. While prenatal population
screening may identify these people, it
would be preferable for health care
providers to encourage their patients to
share this information with relatives
even when they are not pregnant to give
their relatives greater time to adjust to
and appreciate the significance of the
information and to make informed
decisions about what to do with this
information (e.g., whether or not to
undergo carrier testing and how such
information would influence reproductive plans).
Finally, very few of our respondents
in either group reported that their
relatives had pursued carrier testing.
This may suggest that very few relatives
sought testing, as has been observed in
other studies (e.g., Suhr et al. [1994]), or
that relatives did not tell the study
subjects whether or not they had testing.
In part, there was no informational utility in reporting testing decisions back to
study subjects who already knew their
carrier status. Relatives who underwent
testing may have chosen not to reveal
their status for reasons of privacy or to
avoid creating a ‘‘have/have not’’ dichotomy within the family. Additionally,
relatives who did undergo testing and
learned that they were carriers may have
sought social support from someone
other than study participants in an effort
to avoid increasing the perceived burden
on study participants.
Limitations of this study include
the small population size, a relatively low
response rate in both groups, and differences in education and religious
affiliations between groups A and B.
The relatively low response rate may
be due in part to the complexity and the
amount of information the surveys were
intended to solicit. The differences in
education and religious affiliations between the groups may represent the
geographic regions from which the participants were recruited. It also reflects the participation of Northwestern
Memorial Hospital in an outreach
program aimed at educating AJ indivi-
duals about their reproductive risks for a
number of genetic conditions for which
carrier screening is available. Although
we hypothesized that the existence of an
affected proband is the most significant
factor to explain disclosure patterns, our
data may not be generalizable given
these confounding demographics.
Another limitation of this study is
that the data regarding the subjects’
disclosure to relatives and genetic testing
by relatives were not independently
verified in that we did not contact the
relatives. It would be very informative to
know what relatives understand about
their own risks and their reasons for
choosing to undergo or forego genetic
testing. Several studies have addressed
how to contact the relatives without
intruding on the privacy of the proband
and his or her relatives [Winter et al.,
1996; Wilcke et al., 1999].
Finally, our study only assessed
the dissemination of information from
known carriers. We did not assess differences in the genetic counseling provided in the CF clinic versus that
provided in the prenatal genetic counseling clinics, and what role these differences may have had on disclosure
patterns. Nor did we question individuals in group B regarding the utility of
sample letters for disclosure. Clearly,
further research needs to be done to
understand familial obstacles to information disclosure.
Our study documents that the
frequency of and reasons for disclosing CF carrier status to relatives differ
between individuals with and without
an affected family member despite the
fact that the reproductive risks for their
relatives are the same. This has significant
implications for health care professionals who counsel women and couples
regarding reproductive decision-making, because accurate risk assessment is
not possible for individuals who have
incomplete family history information
because they are uninformed or misinformed. While encouraging health
care professionals to counsel all Caucasian individuals of reproductive age
about CF carrier screening regardless
of family history (as recommended by
ACOG, ACMG, and NIH) may make
ARTICLE
this less relevant, it remains unclear how
widely accepted community-based CF
carrier screening will become. Additional research is needed to assess ways
that health care providers can promote
and encourage patients to communicate with all of their relatives in order
to increase informed reproductive decision making.
ACKNOWLEDGMENTS
The authors thank M. Justin Coffey,
Heather McManus, and Erica Wood for
assistance with mailing of surveys and
data entry, as well as Carol Stocking for
wisdom about statistical analyses. L.F.R.’s
participation in this project was sponsored by a Harris Foundation grant. This
research was completed as part of
K.E.O.’s fellowship in clinical medical
ethics at the MacLean Center for
Clinical Medical Ethics, the University
of Chicago.
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