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Volume 6: No. 2, April 2009
ORIGINAL RESEARCH
Family History of Diabetes:
Exploring Perceptions of People at Risk in the Netherlands
Miranda Pijl, MSc, Lidewij Henneman, PhD, Liesbeth Claassen, MSc, Symone
B. Detmar, PhD, Giel Nijpels, MD, PhD, Danielle R. M. Timmermans, PhD
Suggested citation for this article: Pijl M,
Henneman L, Claassen L, Detmar SB, Nijpels G, Timmermans DRM. Family history
of diabetes: exploring perceptions of people at risk in the
Netherlands. Prev Chronic Dis 2009;6(2):A54.
http://www.cdc.gov/pcd/issues/2009/
apr/08_0068.htm. Accessed [date].
PEER REVIEWED
Abstract
Introduction
The aim of this study was to explore the perceptions of causes, risk, and
control with regard to diabetes and the role of family history among people at
increased risk for type 2 diabetes.
Methods
Semistructured interviews were conducted among people aged 57 to 72 years with
(n = 9) and without (n = 12) a family history of diabetes.
Results
Participants mentioned different causes for diabetes; these were often a
combination of genetic and behavioral factors. Some participants with a family
history expressed incoherent causal beliefs; their general ideas about the
causes of diabetes did not explain why their relatives were affected. The role
of genetics as a cause for diabetes was more pronounced when people perceived
diabetes as “running in the family,” and this finding did not necessarily relate
to a high number of affected relatives. Although people with a family history
were aware of the diabetes in their family, they did not always associate their
family history with increased risk, nor did they worry about getting diabetes.
The absence of diabetes in the family was often used as a reason to perceive a
low risk. Participants who primarily perceived genetic predisposition as a cause
felt less able to prevent getting diabetes.
Conclusion
Future diabetes prevention strategies would benefit from giving more attention
to individual perceptions, especially in the context of family history,
explaining the multifactorial character of diabetes, and highlighting effective
ways to reduce the risk.
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Introduction
The prevalence of type 2 diabetes mellitus, a serious health problem, is
increasing. Several factors contribute to this increase, including increasing
obesity and inactivity (1). In high-risk people, the onset of and complications
from type 2 diabetes can be delayed or even prevented by adopting a healthy
lifestyle (2). Prevention is especially important for people with a family
history of diabetes because a family history is one of the strongest risk
factors for type 2 diabetes (3-5). Studies consistently report a 2- to 6-fold
increased risk of diabetes associated with a positive family history, depending
on the number and closeness of relatives affected (6,7). Family history
represents genetic, environmental, and behavioral elements, and the interactions
between them.
Despite the high prevalence of type 2 diabetes, little is known about the
perceptions of diabetes risk among high-risk populations. Quantitative studies
show that people with a family history of type 2 diabetes perceive a higher risk
of getting diabetes compared with those at average risk (8), but they still
often underestimate their actual risk (9). Furthermore, only about half of these
people believe that diabetes is preventable (10,11). Walter and Emery (12) have
shown that in comparing perceptions of people with a family history of diabetes,
cancer, or heart disease, diabetes was generally seen as the least threatening.
More in-depth information about these perceptions of people with a positive
family history of diabetes is needed so that effective targeted prevention
strategies can be designed.
Although family history is not a modifiable factor, communicating familial
risk information may be useful in raising risk awareness, thereby encouraging
preventive behaviors (13). At the same time, familial risk information may
result in a sense of fatalism if people see familial risks as deterministic,
thereby discouraging healthy behavior. According to Marteau and Weinman (14),
understanding the conditions under which genetic risk information does and does
not motivate behavior change is the first step toward developing ways of
communicating such information to maximize its motivational impact. Perceptions
about genetic risk are thought to be mainly influenced by causal beliefs, since
genetic information is specifically about causes (15). In addition, both risk
perception (threat appraisal) and perceptions of control (coping appraisal) can
be used to explain people’s motivation to improve their lifestyle to reduce
their risk for type 2 diabetes (16).
The aim of this study is to explore causal beliefs, perceived risk, and
perceptions of control among people at increased risk for getting diabetes, and
the role of family history in this context. Perceptions of people with and
without a family history are explored to compare and contrast these beliefs
between groups.
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Methods
Participants
A sample was recruited from a database of a population-based targeted
diabetes screening study that was carried out from 1998 to 2000 among
inhabitants of the West-Friesland region of the Netherlands (for details, see Spijkerman et al [17]). Participants (N = 2,315) had been at increased risk of
developing diabetes on the basis of a self-reported risk questionnaire. However,
blood test results excluded them from having developed the disease at that time.
The participants had been informed by letter that they did not have diabetes,
but no further information was provided. For our study, people older than 75
years were excluded; of all eligible people, 20 people with at least 1
first-degree relative with diabetes and 20 people without a family history of
diabetes were randomly selected on the basis of self-reported information.
A municipal official checked the 40 addresses to determine whether people had
moved or died. Two people had died and 1 had moved, leaving 37 people who were
sent a letter of invitation signed by a general practitioner. Exclusion criteria
for the interview study were not speaking the Dutch language and having been
told that they had diabetes. In total, 31 of 37 people (84%) responded to the
invitation (14 were sent a reminder), and 24 people (65%) agreed to participate.
Of the nonparticipants, 1 reported having developed type 2 diabetes; 1
participant was on vacation during the study period; and 5 others did not want
to participate and gave no reason for nonparticipation. In the analyses, 3
participants were excluded because they appeared to have only second-degree
relatives with diabetes, leaving only 9 people with a positive family history
and 12 people without a positive family history.
Methods
The 3 core concepts in this qualitative study — causal beliefs, risk
perception, and perceptions of control — were used to construct a semistructured
interview guide. Additional themes were participants’ personal family history of
diabetes and perceived consequences of diabetes. Two researchers (M.P. and L.C.)
conducted the interviews in the participants’ homes. Interviews were held in
June 2005 and lasted 30 to 60 minutes. The interview guide was refined after the
first 2 interviews, following discussion among 4 researchers (M.P., L.H., L.C.,
and D.T.) using the taped interviews. The Medical Ethical Committee of the Vrije
Universiteit University Medical Center approved the study, and every participant
signed an informed consent form before participation.
Analysis
All interviews were audiotaped and transcribed. Content analyses were
conducted on the transcripts (18). On the basis of found codings, further
analyses were conducted to detect correspondence and differences between people
with and without a family history. Coding was subsequently completed by 2 of the
authors (M.P. and L.H.). To ensure uniform coding, the 2 authors coded each
transcript and then discussed the codings until agreement was reached. For the
analysis, we used Kwalitan version 5.0 (Department of Research Methodology,
Radboud University, Nijmegen, the Netherlands). The most important themes are
presented, and quotations are used to illustrate the meanings that participants
attached to a theme. Participants’ identification number (#), age in years, sex,
and family history (FH) are presented. Perceptions of people without a family
history are used to compare and contrast the findings among people with a family
history and are not described in detail.
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Results
The characteristics of the participants with (n = 9) and participants without
(n = 12) a family history of diabetes who were interviewed are shown in the
Table. Participants with a family history of diabetes reported 1 to 4
affected relatives among first- and second-degree relatives. The mean age in the
group of people with a positive family history was 67 years (range 62-72), and
for the group without a family history was 66 years (range 57-71). Participants
varied in educational level, and in both groups approximately a quarter of the
participants were highly educated.
Causal beliefs
Both genetic and behavioral causes
Participants in both groups were often able to name several causes for
diabetes, including genetic and behavioral causes. Causes mentioned were genetic
predisposition (including family history), unhealthy food (too much fat and
sugar, unvaried diet), lack of physical activity, stress, alcohol intake, and
age. Participants often mentioned genetic predisposition as a cause of diabetes
in combination with an unhealthy lifestyle, whether they had a family history or
not. For example, this man said:
I think [diabetes] has to do with eating habits, if I understood it
correctly. But I think that it’s also a hereditary matter, that someone inherits
it. That the mother or father possibly had it. (#131, 59, M, no FH)
General ideas about causes do not explain diabetes in the family
Compared with people without a family history, those with a family history
sometimes expressed less coherent thoughts about the causes of diabetes. The
following quotation is from a woman who had explained earlier in the interview
that she predominantly saw genetic predisposition as a cause of diabetes, though
when she explained why her relatives developed diabetes, she had another
perception:
I think that it’s always genetically determined whether you get it. . . . I
think that for my mother it was caused by stress, when my father died. . . . For
my father, it was his lifestyle. I think that the diabetes that my father had
wasn’t hereditary for us. Because my father too was always busy. (#106, 64, F,
FH: father, mother, mother’s sister)
Others who generally perceived an unhealthy lifestyle (eg, unhealthy diet,
overweight) to be the cause of diabetes showed confusion about the cause of the
diabetes in their family when lifestyle could not be seen as an explanation for
their affected relative. For example, this man commented:
People with overweight have a high risk of getting diabetes. It has to do
with food. . . . My brother has had diabetes since years. He’s very slim, and he
was also skinny when he got it, so that’s miraculous. Yes, in this case
[heredity] could play a role. (#107; 67; M; FH: brother)
Diabetes runs in my family, thus genetic cause
For people with a family history of diabetes, the role of genetics as a cause
for diabetes was seen as more pronounced when people perceived diabetes as
“running in the family,” particularly when diabetes was passed on from
generation to generation in the same lineage. For example, this woman has a
family that is heavily affected with diabetes, and therefore she believed that
she has inherited the predisposition for diabetes:
Diabetes runs in our family, because my old grandmother suffered from it to a
lesser extent, my father had it very severely, my sister injects, and my brother
controls it with medication. So then you do think there’s something inside you.
(#115; 65; F; FH: mother’s father, father, brother, sister)
However, this phenomenon also occurred when only 1 relative was affected, as
in the following example of a woman who mentioned that diabetes has a genetic
cause:
So I think it’s just genetic, that you can’t prevent it. My risk is somewhat
higher [than that of a random man or woman of the same age], because I have
diabetes in the family. (#118; 62; F; FH: mother)
Behavior triggers the course of diabetes
Although some believed that behavioral factors, such as an unhealthy diet,
were not the cause of diabetes, they thought that these factors might influence the course
of the disease (ie, causing an earlier onset of diabetes or more severe
symptoms) in case of genetic predisposition. The following quotation from a
woman illustrates this perception:
I think it’s in your genes. I don’t think if you eat too many sweets that you
get [diabetes]. You will just get fat. Well, if you have diabetes you shouldn’t
eat sweets. It maybe just makes [the diabetes] worse. (#118; 62; F; FH: mother)
“Inherited lifestyle”
One participant believed that the diabetes in his family was caused by an
“inherited lifestyle,” in particular their diet:
My sister’s lifestyle is sloppy, that might be the cause [of her diabetes].
Being rather overweight, quite a lot of food, never exercising. [As to the cause
of diabetes for my brother,] the only possible thing is that he has the same
lifestyle as my sister. Eating a lot of sweets and a lot of food, lots of fat.
That might be an inherited factor. (#132; 64; M; FH: brother, sister)
Perceived risk
Diabetes in my family, therefore increased risk
Only 4 of 9 participants with a positive family history perceived a slightly
higher risk when comparing themselves with other people of the same age, because
of the diabetes in their family.
Maybe I have a higher risk [of getting diabetes] because my mother had
diabetes. (#108, 69, F, FH: mother, mother’s mother)
Diabetes in my family, but no risk for me
Although participants with a family history did mention that they had
diabetes in their family, they did not always seem to associate this information
with their own risk. For example, this woman said:
The risk of getting diabetes is on my mind. I do have a mother and a
grandmother who had it. But [my chance of getting diabetes] is the same,
everybody can get it, I don’t think my risk is higher or lower. (#113; 71; F; FH:
mother, mother’s mother)
Diabetes not in my family, so no risk for me
Most of the participants without a family history perceived a low risk of
getting diabetes. Only a few (3/12) perceived themselves at a slightly higher
risk than average because they considered themselves to be overweight and to
have an unhealthy lifestyle. Moreover, the absence of diabetes in the family was
often (7/12) mentioned as a reason to perceive a low diabetes risk. For example,
this woman:
The [diabetes] risk must be very low, because at home there were 7 of us, and
none of us has it! (#130; 71; F; no FH)
Despite high risk-awareness, low emotional response
Participants who did mention severe consequences of diabetes and sometimes
even perceived a high risk due to an extensive number of affected family members
still did not worry about getting diabetes. The following quotation is from a
woman who mentioned in the interview that she perceived a high risk of getting
diabetes:
Blindness, the legs, the muscles or nerves in the legs of my father were
affected. . . . No severe illness, they say you can become 100 years old with
it, but I think the side effects are very hard. I never think about getting
diabetes. [Having diabetes] is not a problem; I mean, you just pay more
attention to what you eat. (#115; 65; F; FH: mother’s father, father, brother,
sister)
Perceptions of control
Although some people correctly stated that having a healthy diet and being
physically active can delay the onset of or even prevent diabetes, most
participants in both groups were unaware of ways to prevent diabetes.
Participants with a family history held different beliefs about ways to control
their risk, depending on their causal beliefs.
Genetic cause, cannot control risk
Participants with a family history of diabetes who mainly perceived genetic
causes for getting diabetes all felt that they were not able to prevent it. At
most, they thought they might be able to postpone the disease by adopting a
healthy lifestyle, like this woman:
I think that it’s always genetically determined whether you get [diabetes]. I
think there’s little you can do about it then. You might be able to postpone it
a little, if you know you can get it, by paying attention to what you eat.
(#106; 64; F; FH: father, mother, mother’s sister)
Behavioral cause, can control risk
In contrast, those with a family history who predominantly saw lifestyle as a
cause of diabetes did believe there were ways to prevent diabetes, as this man's
comments illustrate:
Of course you always have an influence [on the chance of getting diabetes] by
not doing things that can cause diabetes . . . like having lots of fat and
drinking sweet cola. (#107; 67; M; FH: brother)
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Discussion
Both people with and without a family history of diabetes mentioned several
causes for diabetes, including genetic and behavioral causes. This finding
suggests that people correctly see diabetes as a multifactorial disease. Walter
and Emery (19) earlier described the multifactorial model of familial disease
risk. They also showed that people at risk for diabetes view lifestyle factors
as triggering an underlying risk, for example, genetic risk. In our study, some
participants thought that lifestyle could worsen the diabetes or that it would
develop sooner in case of genetic predisposition. None of them mentioned that an
unhealthy lifestyle alone would trigger an underlying risk. One participant,
however, pointed out that lifestyle might be an inherited factor. This may imply
that some people identify behavior as heritable. Because only 1 participant
mentioned this aspect, it is difficult to draw such a conclusion.
A contrast between both groups concerning causal beliefs was that people with
a family history of diabetes were less coherent and more confused when talking
about the causes of diabetes, since their general beliefs about the causes did
not always explain why their relatives were affected. Being incoherent about
causal beliefs has been identified previously for diabetes patients. Though
aware of possible risk factors for diabetes (eg, being overweight, physically
inactive, having a family history), patients without these risk factors could
not understand how they had developed the disease (20). Thus, their general
ideas about the causes of diabetes did not explain why they were affected. It
seems that people have difficulty in understanding the interplay between genes
and environment or behavior (eg, unhealthy lifestyle). Possibly people have more
difficulty in integrating risk information from more than 1 source than when
there is a single risk factor for a disease, as Marteau and Weinman have
suggested (14).
People mostly perceived a genetic cause for getting diabetes when they
perceived diabetes as “running in the family.” This belief was reported when
several affected relatives were of the same lineage, as one might expect.
However, a woman with only 1 affected relative also perceived diabetes as
running in the family and perceived a higher risk of getting diabetes. In a
quantitative study designed to identify determinants of familial risk perception
of common diseases (cancer, coronary heart disease, and diabetes), Walter et al
(21) found that believing the disease “runs in the family” is an important
predictor of perceiving a familial risk, together with believing the
disease has a genetic cause and diabetes is a serious condition. People
without a family history often see not having a family history as protective,
which might indicate that they also perceive diabetes is caused by a
genetic predisposition when it runs in the family.
Some people who saw diabetes as running in the family indeed perceived an
increased risk of getting diabetes because of the occurrence of diabetes in the
family. This finding might indicate that people associate their beliefs about
heredity of diabetes with their perception of being at risk. Participants with a
family history perceiving behavioral causes for getting diabetes had a different
risk perception. Though they acknowledged their family history, when comparing
themselves with other people of the same age, they still did not perceive a
higher risk. In line with these findings, Harrison et al (22) found that less
than 40% of the people with a family history of diabetes perceived themselves to
be at increased risk. Despite their family history of diabetes, participants in
this study did not feel worried about getting it. Walter and Emery (12) earlier
described that diabetes was not viewed as a serious disease but as a chronic
disease of older age and at worst a minor inconvenience. In keeping with these
findings, Eborall et al (23) described low levels of anxiety among participants
of a screening program for type 2 diabetes in the east of England, even those
eventually diagnosed with type 2 diabetes.
This study suggests that people with a positive family history, especially
people who perceive genetic causes for getting diabetes, are less likely than
others to believe that diabetes is preventable, supporting the results of
Harwell et al (10). In contrast, it seemed that people who perceived behavioral
causes for developing diabetes did believe that diabetes was preventable. A
previous study by Senior et al (24), considering perceptions about an inherited
predisposition to heart disease (familial hypercholestrolemia), showed evidence
for fatalistic beliefs when the underlying cause of a positive test result was
seen as genetic, and no such evidence was found for perceptions of underlying
behavioral causes.
Some limitations of our study need to be addressed. Participants were older
adults who might consider health risks a part of getting older, may be less
engaged in preventing disease, and may have had fewer concerns about getting
premature disease due to their family history. The participants had been in a
stepwise-based screening study some years earlier; therefore, their knowledge
about diabetes might have been better than that of the average population.
Nevertheless, these results suggest that, even in this group, knowledge about
diabetes and especially ways to prevent it were suboptimal. Although the small
sample size of the study may limit conclusions, we have gained a deeper
understanding of the perceptions and beliefs of people with a family history of
diabetes.
This study suggests that people probably used causal beliefs to construct
their perceptions of risk and control (ie, when people perceive genetic causes
for diabetes, they tend to have a higher perception of risk and lower perception
of control). Perceptions of risk and control in turn may be important motivating
factors for preventive health behaviors (16). People with a family history of
diabetes seem to have incoherent causal beliefs; therefore, prevention programs
should promote correct understanding of the multifactorial causes of type 2
diabetes among people at high risk due to their family history, which might have
a positive effect on their perceptions of risk and control and, directly or
indirectly, on preventive behaviors. In addition, people without a family
history would also benefit from clear information on this topic.
The findings of the study point to the need for more research on this topic,
for example, on the relationship between causal beliefs and both risk perception
and perception of control.
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Acknowledgments
This study was supported by the Centre for Medical Systems Biology in the
framework of the Netherlands Genomics Initiative.
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Author Information
Corresponding Author: Miranda Pijl, MSc, Department of Public and
Occupational Health, EMGO Institute, VU University Medical Center, PO Box 7057,
1007 MB Amsterdam, the Netherlands. Telephone: +31204448381. E-mail:
mailto:m.pijl@vumc.nl.
Author Affiliations: Lidewij Henneman, Liesbeth Claassen, Danielle R.M.
Timmermans, Department of Public and Occupational Health, EMGO Institute, VU
University Medical Center, Amsterdam, the Netherlands; Symone B. Detmar, TNO
Quality of Life, Leiden, the Netherlands. Giel Nijpels, Department of General
Practice, EMGO Institute, VU University Medical Center, Amsterdam, the
Netherlands.
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