Arches. Photo by Daniel Chia
HOPES: Huntington's Outreach Project for Education, at Stanford
Jun
26
2010

Couple Relationships and Huntington’s Disease Testing

Huntington’s disease presents unique psychosocial issues due to its late onset and hereditary nature. One of the major issues of course is stress, which can come from many sources and has many effects (for general discussion of stress and HD, click here. A major source of psychosocial stress associated with HD comes from predictive testing which became available in the United States in 1993.

Extensive research has focused on the person undergoing predictive testing, with a good number of studies reporting that the tested person’s benefit from the knowledge of their genetic status outweighed their post-test psychosocial distress. However, less research has focused on the psychological impact that predictive testing may have on those at risk for HD and their partners, family and friends. This research is important because HD affects many more people than just the person who has it. Moreover, the hereditary nature of the disease can also lead to difficult questions about reproduction and about the possibility of other family members having the disease.

Fortunately, researchers are now focusing more of their attention on predictive testing and its effects on the couple relationship. In the remainder of this section, we review their key findings to date.

What percentage of couples looks favorably upon predictive testing? And what motivations drive their decisions?

In a 1989 study in Belgium, where HD predictive testing has been available since 1987, Evers-Kiebooms found that a moderate majority of people at-risk for HD and their non-carrier partners looked positively on predictive testing. Out of 349 study subjects, 66% of the at-risk adults and 74% of their partners wanted testing for the at-risk individual. The difference between these percentages can partly be explained by the difference in motivations between the at-risk person and his/her partner in approving the predictive testing. When asked why they approved, at-risk adults tended to cite worries about their futures, while their partners tended to cite worries about current and/or future children. A reason that some couples decided not to undergo predictive testing was concern about the effects of the testing on their relationship; this concern was more often a major consideration for non-carrier partners than for the at-risk adults. (For specifics on the process of HD predictive testing, please click here.

Is there a theory on how predictive testing affects couple relationships?^

Yes, a perspective called family systems theory, developed over the past few decades, has proven particularly useful in genetic counseling. This theory is especially relevant to the genetic counseling of couple relationships because its central focus is on the family rather than the individual. The family systems theory describes human behavior as a consequence of family relationship patterns, rather than individual psychology. Consequently, family systems theory can help explain the effects of predictive testing on couple relationships by analyzing how family relationship patterns can influence post-test behavior.

In a 2004 study by Richards and Williams, 43 couples were divided into two groups: those that chose to undergo predictive testing and those that chose not to. Couples in both groups answered the same questionnaire before predictive testing, then 6 months later (3 months after those tested received their test results), and again 24 months after the first questionnaire. The questionnaire consisted of 32 Dyadic Adjustment Scale questions that measured couple relationship functioning, known as a “couple score.” Those couples that received higher couple scores frequently interacted and communicated with each other, rarely disagreed with each other on significant marital issues, and settled disagreements in a way that was satisfying to both partners.

The major finding of this study was that, over the 24 month period, there was no statistically significant difference in couple scores between couples who had decided to undergo predictive testing and couples who had decided not to. The key conclusion was that predictive testing has few negative effects on couple relationships. As the authors noted, this conclusion matches the findings of several other studies (Tibben et al., 1993a; Cordori and Brandt, 1994; Quaid and Wesson, 1995; Taylor and Myers, 1997. For a look at these studies, please see “For Further Reading” at the end of this chapter).

An additional finding from the 2004 study is interesting. The couples that underwent predictive testing were categorized into couples in which the at-risk partner was a carrier and couples in which the at-risk partner was a non-carrier. Unexpectedly, the carrier couples had higher couple scores (stronger couple relationships) of statistical significance than the non-carrier couples. This suggests that, for some couples, the knowledge that their at-risk partner did not have HD had a greater negative effect on their marital relationship than the knowledge that their partner did have HD. The authors give a possible explanation: “The threat of HD may have served as a factor in the continuance of the relationship. Once this threat is removed, partners may no longer feel a duty or need to remain in the marriage to care or to be cared for.”

Another possible explanation is provided by examining family patterns via family systems theory rather than individual behavior. Family systems theory suggests that the couple relationship can be negatively affected when one or both partners have different expectations for the predictive test’s results. When the results prove to be different from expectations, conflict can arise contributing to relationship deterioration and lower couple scores. Studies by Huggins et al. and Soldan et al. have found that professional genetic counseling can benefit the couple relationship by helping partners discuss their expectations of the predictive test’s results and their coping strategies (See “Further Reading” below for links to these two studies).

What does the medical literature say about the pros and cons of predictive testing for couple relationships, especially psychosocial aspects?^

Similar to the work of Richards and Williams reviewed above, a study by Decruyenaere in 2004 also used the Dyadic Adjustment Scale to measure changes in the couple relationship for 5 years following predictive testing. But the study also collected qualitative data from separate interviews with the at-risk persons and their partners. Qualitative data are useful because they can provide more thorough explanations for trends observed in couple relationship over time. The specific couple relationship examined in the Decruyenaere study was marriage.

In this study, all at-risk persons were undergoing predictive testing, with 26 carriers and 14 of their partners, and 33 of non-carriers and 17 of their partners participating in the study. The main finding was that the majority (70%) of the tested persons did not have a change in marital status over the 5 years of the study. As for the quality of the marital relationship, half of the couples reported no change in that interval compared to the quality before the predictive testing. Out of those that did report change, non-carrier couples cited less distress and more communication. Carrier couples that experienced increased relationship quality over the five years cited more mutual support.

A conclusion that can be drawn from this study is that the test result does not by itself predict outcomes in the couple relationship; even couples with negative test results for HD may experience post-test psychosocial distress and couple relationship breakdown. The important factor for couples undergoing predictive testing is whether the test result causes role shifts that upset the balance of the pre-test couple relationship. For example, two couples that received positive test results reported frustration as the partners shifted toward caretaking roles even before the people with HD showed any symptoms. In another couple tested, a woman believed to be at risk for HD gained self-esteem from a negative result. With low self-esteem before the test, she had married someone who did not match her ideals in a spouse. After the testing showed she did not have HD, she regretted her decision to marry her husband, clearly leading to relationship deterioration.

Since undesired shifts in roles may contribute to couple relationship breakdown whether the test result is positive or negative, the researchers of this study strongly support post-test counseling. Post-test counseling can help couples find and maintain a new balance that is satisfying to both partners. This counseling should include open communication between the partners, with special attention paid to the desires and worries of each partner.

Conclusions^

It is clear from these studies that the psychosocial impact of predictive testing on the couple relationship is complex, with a number of factors that contribute to both positive and negative outcomes. First, the Richards and Williams study shows that pre-test discussion by the couple can be very helpful to their relationship. Such discussion can better prepare the couple for the test result by encouraging understanding of each other’s expectations of and reactions to the test result. In particular, this pre-test assessment can help identify particular challenges that the couple may face after the testing and may lead to re-consideration of testing in the first place. Complementing the Richards and Williams study, the Decruyenaere study shows the importance of post-test counseling. Post-test counseling can help protect against adverse effects of predictive testing by encouraging open discussion of each partner’s concerns as well as identification of any potential role-shifts that may disrupt the couple relationship.

Further Reading^

  • Decruyenaere M, Evers-Kiebooms G, Cloostermans T, Boogaerts A, Demyttenaere K, Dom R, Fryns JP. Predictive testing for Huntington’s disease: relationship with partners after testing. Clinical Genetics. 2004 Jan;65(1):24-31.
    This study is not only easy-to-read but also optimistic in its finding that most marital relationships remained the same five years after predictive testing, regardless of the test results.
  • Evers-Kiebooms G, Swerts A, Cassiman JJ, Van den Berghe H. The motivation of at-risk individuals and their partners in deciding for or against predictive testing for Huntington’s disease . Clinical Genetics. 1989 Jan;35(1):29-40.
    This early study found that the majority of at-risk persons and their partners looked favorably upon predictive testing, although the at-risk individual and his/her partner’s reasons for deciding to take the test varied. This study took place before predictive testing began in 1993; however, the couples’ explanations for deciding on predictive testing are still eye-opening and relevant.
  • Huggins et al. Predictive testing for Huntington disease in Canada : Adverse effects and unexpected results in those receiving a decreased risk . 1992 Am J Med Genet 42:508-515.
  • Richards F, and Williams K. Impact on couple relationships of predictive testing for Huntington disease: a longitudinal study. American Journal of Medical Genetics Part A. 2004 Apr 15;126(2):161-9.
    This is an easy-to-read article that is especially interesting because of its discussion on the benefits of pre- and post-test counseling.
  • Soldan et al. Psychological model for presymptomatic test interviews: Lessons learned from Huntington disease . 2000 J Genet Couns 9:15-31.

Studies, in addition to Richards and Williams 2004, that found few negative effects of predictive testing on couple relationships:

  • Codori AM, et al. Psychological costs and benefits of predictive testing for Huntington’s disease. 1994 Am J Med Genet 54:174-184.
  • Quaid KA, et al. Exploration of the effects of predictive testing for Huntington disease on intimate relationships. 1995 Am J Med Genet 57:46-51.
  • Taylor CA, et al. Long-term impact of Huntington disease linkage testing . 1997 Am J Med Genet 70:365-370.
  • Tibben A, et al. On attitudes and appreciation 6 months after predictive DNA testing for Huntington disease in the Dutch program . 1993 Am J Med Genet 48:103-111.

-C. A. Chen 5-7-07