Prenatal screening for cystic fibrosis: psychological effects on carriers and their partners

Perceived barriers to paternal expanded carrier screening following a positive maternal result: To screen or not to screen

Expanded carrier screening identifies individuals who are at risk of having a child with an autosomal recessive condition. The most accurate risk assessment requires that both mother and father undergo carrier screening to determine whether they are carriers of the same autosomal recessive condition. A couple identified as carriers of the same condition has a 25% chance of having a child with that condition. However, the father does not always opt for carrier screening following a positive result in the mother. This study aimed to identify barriers that prevent the father from carrier screening after a positive finding in the mother. A total of 58 women participated in this study. All participants had undergone expanded carrier screening prior to the study and had met with a genetic counselor for a pre-test, informed consent session. Of the 58 women, 34 had partners who did not undergo screening and 24 had partners who did. Participants completed a survey to determine the barriers that prevented the father of the baby's participation. We report that the mother's insurance type, whether the father has insurance, relationship status, and knowledge of the carrier screen showed statistically significant differences between women whose partners underwent screening and those that did not. In summary, our finding suggests that increasing insurance coverage of paternal screening and improving the patient's knowledge of the expanded screen would encourage paternal screening.

Patient actions and reactions after receiving negative results from expanded carrier screening

With the expansion of carrier screening to general preconception and prenatal patient populations, most patients will receive negative results, which we define as indicating <25% risk of having a child with a genetic condition. Because there is limited experience with expanded carrier screening, it is important to understand how receiving negative results affects patients, especially as providers, payers, and policymakers consider whether to offer it. In this mixed-methods study, we asked preconception patients enrolled in the NextGen study about their expectations and experiences receiving negative expanded carrier screening results. Participants completed surveys at study enrollment (n = 110 women, 51 male partners), after receiving carrier results (n = 100 women, 38 male partners), after receiving secondary findings (n = 98 women, 36 male partners), and 6 months after receiving results (n = 95 women, 28 male partners). We also interviewed a subset of participants 12 to 24 months after receiving results (n = 24 women, 12 male partners). We found minimal negative emotional impact and privacy concerns, increased confidence in reproductive plans, and few changes to health behaviors, although some patients made health decisions based on misunderstandings of their results. These findings suggest that expanded carrier screening causes minimal psychosocial harms, but systems are needed to reduce the risk of misinterpreting results.

Responsible implementation of expanded carrier screening

This document of the European Society of Human Genetics contains recommendations regarding responsible implementation of expanded carrier screening. Carrier screening is defined here as the detection of carrier status of recessive diseases in couples or persons who do not have an a priori increased risk of being a carrier based on their or their partners' personal or family history. Expanded carrier screening offers carrier screening for multiple autosomal and X-linked recessive disorders, facilitated by new genetic testing technologies, and allows testing of individuals regardless of ancestry or geographic origin. Carrier screening aims to identify couples who have an increased risk of having an affected child in order to facilitate informed reproductive decision making. In previous decades, carrier screening was typically performed for one or few relatively common recessive disorders associated with significant morbidity, reduced life-expectancy and often because of a considerable higher carrier frequency in a specific population for certain diseases. New genetic testing technologies enable the expansion of screening to multiple conditions, genes or sequence variants. Expanded carrier screening panels that have been introduced to date have been advertised and offered to health care professionals and the public on a commercial basis. This document discusses the challenges that expanded carrier screening might pose in the context of the lessons learnt from decades of population-based carrier screening and in the context of existing screening criteria. It aims to contribute to the public and professional discussion and to arrive at better clinical and laboratory practice guidelines.

"I'm Healthy, It's Not Going To Be Me": Exploring experiences of carriers identified through a population reproductive genetic carrier screening panel in Australia

Advancing genetic testing technologies mean that population-based carrier screening for multiple inherited conditions is now available. As the number of genetic conditions being screened increases, there is a need for research into how people experience these screening programs. This research aimed to explore how women experience simultaneous carrier screening for three inherited conditions: cystic fibrosis (CF), spinal muscular atrophy (SMA), and fragile X syndrome (FXS). A qualitative approach was adopted using in-depth semi-structured interviews to explore the experiences of ten female participants: five SMA carriers, three CF carriers, and two FXS premutation carriers. Eight participants were pregnant when offered screening by their general practitioner or obstetrician and the decision to have screening was described as straightforward. Participants reported experiencing emotional responses such as anxiety and stress while waiting for either their partner's carrier screen result (CF or SMA carriers) or the pregnancy's CVS result (FXS carrier) and sought additional information about the relevant condition during this time. Most participants were in favor of population carrier screening for these conditions, preferably prior to conception. Genetic counselors played an essential role in supporting couples after they received a carrier result given the variable consent processes undertaken when screening was offered. Further research should focus on the development of reliable online information tailored to people receiving carrier results and strategies for raising awareness of the availability of population carrier screening within the community. © 2016 Wiley Periodicals, Inc.

Population-based carrier screening for cystic fibrosis: a systematic review of 23 years of research

Cystic fibrosis is the most common severe autosomal recessive disease, with a prevalence of 1 in 2,500-3,500 live births and a carrier frequency of 1 in 25 among Northern Europeans. Population-based carrier screening for cystic fibrosis has been possible since CFTR, the disease-causing gene, was identified in 1989. This review provides a systematic evaluation of the literature from the past 23 years on population-based carrier screening for cystic fibrosis, focusing on the following: uptake of testing; how to offer screening; attitudes, opinions, and knowledge; factors influencing decision making; and follow-up after screening. Recommendations are given for the implementation and evaluation of future carrier-screening programs.

Respiratory physicians and clinic coordinators' attitudes to population-based cystic fibrosis carrier screening

BACKGROUND

Attitudes of Australian CF healthcare professionals toward population-based cystic fibrosis (CF) carrier screening were examined.

METHOD

A purpose-designed questionnaire was distributed to 111 respiratory physicians and 30 CF clinic coordinators throughout Australia.

RESULTS

Seventy-one questionnaires (52 physicians and 19 coordinators (46.8%, 63.3% respectively)) were returned. Forty respondents (56.3%) supported population-based carrier screening for CF. Support for screening was associated with rating the factors: carrier risk being 1 in 25 (OR 1.72 (1.12, 2.65)), reassurance when both partners test negative (OR 1.67 (1.12, 2.46)) and the daily treatment regimen for CF patients (OR 1.59 (1.05, 2.42)) as important. Opposition to screening was associated with identifying potential discrimination against carriers as a disadvantage (OR 0.3 (0.12, 0.88)), and limitations of predicting clinical outcomes as a barrier (OR 0.46 (0.25, 0.83)).

CONCLUSIONS

There is moderate support for population-based carrier screening for CF by Australian CF healthcare professionals. Perceived barriers to implementation are surmountable.

Attitudes of health care professionals toward carrier screening for cystic fibrosis. A review of the literature

Recent technological developments in molecular genetics facilitate the large-scale detection of inherited genetic disorders and allow an increasing number of genetic conditions to be screened for (American College of Medical Genetics 2012). This technological evolution creates the background which makes reflection necessary about the desirability to offer community-based (preconception) carrier screening in the healthcare system. A positive attitude of potential providers is vital to the success of a screening program. Therefore, the objective of this article is to elaborate a review of the attitudes of healthcare professionals toward carrier screening. Examination of existing carrier screening programs could provide such information. The literature review will be focused on the attitudes toward carrier screening for cystic fibrosis (CF). The databases Pubmed and Web of Science, as well as the interface Google Scholar, were searched using the keywords for the period 1990-2011. Studies were selected if they were published in a peer-reviewed journal in English and described the attitudes of potential providers toward carrier screening. Eleven studies were retrieved describing the attitudes toward carrier screening for CF. In total, seven studies reported attitudes toward the best time for carrier screening; four studies described opinions toward the best setting to offer CF carrier screening; six studies investigated the willingness to be involved in a carrier screening program, and in total 11 articles reported the concerns about offering carrier screening. Ten papers described a general attitude toward carrier screening. We can conclude that health care providers state willingness to be involved in a carrier screening program, but there is need for appropriate education as well as adequate support given the time constraints already present in consultation. The prospect of an increasing number of genetic disorders for which screening becomes possible, and the potential increasing demand for such screening in the future calls for the need for further debate on the desirability of carrier screening and relevant questions such as the conditions screened, the providers involved, the information provision, and counseling.

Factors associated with perceived uncertainty among parents of children with undiagnosed medical conditions

Uncertainty is a pervasive characteristic of illness. Yet little is known about the individual or situational factors that contribute to perceptions of uncertainty. The present study aims to examine the factors that contribute to perceived uncertainty among parents of a child with an undiagnosed condition. Two hundred sixty-six parents of a child, or children, affected by an undiagnosed medical condition for at least 2 years completed an electronically administered mixed-methods survey assessing theoretical predictors of perceived uncertainty. Multivariate linear regression analyses were used to identify the relationship of key variables to perceived uncertainty. Parents' perceived control and optimism were negatively associated with uncertainty (B=-4.044, P≤0.001, B=-0.477, P≤0.05). Subjective disease severity was positively associated with perceived uncertainty (B=1.797, P≤0.05). Our findings suggest that parents who experience greater uncertainty feel less control over their child's medical condition, which may lead to less effective coping and poorer adaptation. Parents who are less optimistic or who perceive their child's disease as more severe may benefit most from interventions that target situations where parents perceive the least control, thereby enhancing coping and ultimately, adaptation.

Attitudes toward fragile X mutation carrier testing from women identified in a general population survey

Fragile X syndrome is primarily due to a CGG repeat expansion found in the FMR1 X-linked gene. In a previous study, we conducted focus groups with women to assess their attitudes towards fragile X carrier screening. In this follow-up study, we conducted in-depth interviews of general population reproductive-age women who were identified as carriers. We explored their attitudes toward testing for carrier status of the fragile X mutation. These women underwent screening primarily to participate in a research project rather than in search of a diagnosis for specific symptoms. As such, these women were wholly unprepared for positive carrier results. Their responses about their results and carrier screening, in many cases, were being worked out over the course of the interview itself. The most salient finding of this work is the apparent lack of relevance of carrier status to these women. Many expressed that although the information could be relevant in the future, it is not relevant at this stage of their lives in terms of family planning (either with respect to having unaffected offspring or to premature ovarian failure) and personal relationships. Although issues of abortion seemed prominent in the focus groups, we found that carrier status did not have an apparent effect on women's attitudes about termination. We hypothesize this may be related to the fact that women had not processed their new carrier status and had not related it to previously-formed personal opinions. The findings of this work have significant implications for genetic counseling and population screening. Genetic counselors should be mindful that general population women may not recognize the immediate importance of their carrier status even when literature is provided and discussed prior to providing a sample. As part of comprehensive genetic counseling, counselors should identify the reproductive life stage of the woman receiving the new information and help her identify when this information would be more meaningful in her life. Counselors can assist in setting up a personalized road map with specific types of services that will be more applicable to the woman as her carrier status becomes more relevant.

Evaluating Genetic Counseling: Client Expectations, Psychological Adjustment and Satisfaction with Service

Periodic evaluations of genetic counseling services are useful for determining the effectiveness of counseling in meetings its psycho-educational aims, as well as identifying where improvements to the service may be made. This study aimed to evaluate the genetic counseling services provided by Genetic Services of Western Australia (GSWA) to determine the impact of counseling on client expectations, satisfaction with the service, and psychological adjustment, defined as wellbeing and perceived personal control (PPC). A total of 122 clients participated in a self-administered survey conducted pre- and post-counseling. Client expectations of the service as a means of providing information were met, and opportunities for counselors to meet client's expectations of psychological support were identified. Furthermore, counseling was found to maintain and enhance psychological wellbeing of clients. The role of counseling in facilitating the development of PPC was a key contributor to a high sense of satisfaction in clients.

Genetic counseling: the impact in Indian milieu

OBJECTIVE

To assess the impact of genetic counseling in Indian milieu.

METHODS

A study of 83 Indian consultants who were provided genetic counseling was carried out to understand their expectations, satisfaction with genetic counseling and its effects on reproductive decision.

RESULTS

Most of the families were referred for the diagnosis and the treatment of the disorder in the proband. The consultants understood the medical facts about risk of recurrence and were satisfied with genetic counseling. There was no change in reproductive plan after genetic counseling in most of the cases.

CONCLUSION

The reproductive decision was mainly correlating with the presence or absence of normal live children in the family and availability of prenatal diagnosis.

Evaluation of cystic fibrosis carrier screening programs according to genetic screening criteria

Genetic screening programs should meet certain criteria before they can be introduced into the community. The aim of this study was to discuss pilot studies for cystic fibrosis (CF) carrier screening before and during pregnancy in the light of important genetic screening criteria. Overall, CF carrier screening meets the prerequisites that justify screening. However, more specific criteria for the development of screening programs were not always taken into consideration. Most project leaders concentrated on uptake as an important outcome, and less on informed decision-making. To further investigate the long-term psychological and social effects of genetic screening, continuous monitoring of screening projects is recommended.

Research directions in genetic counselling: a review of the literature

There is a growing body of literature considering genetic counselling services in a variety of clinical settings. This literature encompasses both predictive and diagnostic testing, from the viewpoints of service providers and recipients. It also embraces a wide range of conceptions of the nature and goals of genetic counselling. However, research in this area has been criticised for a focus on outcome rather than process, and it has been suggested that this focus limits its practical use. The purpose of this review is twofold: (1) to describe the varying concepts of counselling which appear to be utilised in published work and (2) to discuss the possible applications of this work to practice.

Cystic fibrosis mutation frequencies in upstate New York

Upstate New York patients (100) with cystic fibrosis (i.e., 200 CF chromosomes), 72 from the CF center in Syracuse and 28 from a Buffalo CF center, were analyzed for their CF-causing mutations using restriction enzyme digest, single-strand conformation analysis (SSCA), and Heteroduplex (HA) analysis. Polymerase chain reaction (PCR) amplified products from all 27 CFTR exons using primers that included flanking intron junction sequence were investigated. More than 120 known cystic fibrosis transmembrane conductance regulator (CFTR) disease-causing mutations were screened. Four novel CFTR disease-causing mutations were identified (N287Y in exon 6b, 1259insA in exon 8, R1070P in exon 17b, and CF?20kbdel14b-18). A detection rate of 96% of the combined Syracuse and Buffalo population CF chromosomes was obtained.

Cystic fibrosis carrier population screening: a review

Population screening for cystic fibrosis (CF) carriers, now possible because of the cloning of the CFTR gene, merits evaluation because CF is common, serious, and without satisfactory treatment, and because prenatal diagnosis is available. Clinical trials of CF population carrier screening are reviewed. These trials have involved pregnant women, adults of both sexes of reproductive age, or adolescents. Schools, the usual setting for screening programs for adolescents, provide an excellent opportunity for a formal educational component and for comprehensive coverage of the population, but compared to a health-care setting, may entail subtle coercion and may compromise confidentiality. In the case of adults, many say they prefer screening before conception but do not see a physician for evaluation before conception and providers find screening more readily accomplished in the setting of a prenatal visit. Two large U.S. studies of prenatal screening with quite different subject populations and health-care settings encountered few of the adverse outcomes originally predicted for CF carrier population screening.

Issues in implementing prenatal screening for cystic fibrosis: results of a working conference

PURPOSE

To summarize a conference convened to examine how cystic fibrosis screening might appropriately be introduced into routine prenatal practice.

METHODS

Participants included experts from various relevant disciplines. Systematic reviews and data from individual trials were presented; issues were identified and discussed.

RESULTS

Judged by published criteria, prenatal cystic fibrosis screening is suitable for introduction. Screening can be performed cost-effectively by identifying racial/ethnic groups at sufficient risk and then using either of two models for delivering laboratory services. Validated educational materials exist. Ethical issues are not unique.

CONCLUSIONS

Once adequate facilities for patient and provider education, testing, counseling, quality control, and monitoring are in place, individual programs can begin prenatal screening for cystic fibrosis.

Effects of a smoking cessation program for pregnant women and their partners attending a public hospital antenatal clinic

This study aimed to assess the effect of a hospital-based smoking cessation intervention delivered by midwives during routine antenatal and postnatal care on the smoking habits of pregnant women and their partners. At the first antenatal visit, women in the intervention group (n = 110) were given a demonstration of the immediate effects of smoking on foetal heart rate, brief smoking cessation advice and smoking cessation booklets for themselves and their partners; at delivery, they were given brief advice and a booklet about postpartum cessation. Compared with an historical control group who received usual care (n = 110) and assuming those lost to follow-up continued to smoke, biochemically-verified maternal cessation sustained from at least 24 weeks gestation to late pregnancy was 6.4% in the intervention group and 1.8% in the comparison group. However, there was no difference between maternal quit rates at six months postpartum. Partners were more likely to try to quit in the intervention group, but quit rates did not differ. Exposure to the intervention was not associated with increased levels of psychological distress, as measured by the 12-item General Health Questionnaire. We conclude that this type of intervention, when implemented by staff during routine care, is probably associated with a small improvement in maternal cessation in pregnancy, similar to that produced by minimal advice to quit smoking.

Maternal anxiety and attitudes to universal neonatal hearing screening

Neonatal hearing screening of all babies within the maternity unit is now feasible using transient evoked otoacoustic emission (TEOAE) recording. However, in many maternity units in the United Kingdom, the majority of babies are discharged within the first 48 hours. During the first two days of life, there is a higher proportion of babies in whom emissions cannot be recorded. A universal TEOAE hearing screen has been implemented in Whipps Cross Hospital. As 70% of the babies are discharged from the maternity unit before they are 48 hours old, a two stage screen was implemented, with failure at the initial TEOAE test being followed by a retest after 4-6 weeks. The maternal anxiety caused by this model was investigated in 288 mothers enrolled for the initial TEOAE test. Generally, anxiety was low and attitudes towards the screen were positive. Ninety-seven per cent of mothers considered the screen to be worthwhile at the initial test with 15% feeling it had caused some anxiety but less than 1% being very worried. The mothers who had some anxieties were not dissatisfied with the screen, and within this group there was no increase in the proportion of babies who had failed the initial test. At the retest, two of 57 mothers (3.5%) considered they were very worried, but there was no significant deterioration in attitude towards the screen. Spielberger's State-Trait Anxiety Inventory revealed no significant difference in the anxiety state of the retest group when compared with a control group whose babies had not received a neonatal hearing test. The results of the initial test and the retest did not influence the anxiety state of the mothers. Ways of minimizing anxiety caused to a minority of mothers whilst maintaining positive attitudes to the screen are discussed.

Educational material about genetic tests: does it provide key information for patients and practitioners?

Genetic testing for common conditions will be used increasingly in primary care, but resources for patient counseling are decreasing. It is also necessary that primary care practitioners be better equipped to do basic genetic counseling. Therefore, the quality of informational materials for practitioners and patients is important. It was unknown how often key elements recommended by policy groups were actually included in such material. It was our aim to determine the content of printed informational material for practitioners and patients on genetic testing. We performed (1) a telephone survey of organizations in the United States that developed genetic tests or services and (2) a content analysis of pamphlets obtained from these organizations to determine the presence of 10 critical elements necessary to evaluate the appropriateness and performance of the tests. Almost 95% (169/178) of organizations responded to our survey; 131/169 (78%) reported using informational materials. We analyzed 115 pamphlets collected from 125/131 (95%) organizations. Elements least frequently included in the pamphlets were risks and benefits, patient rights, and intended use or purpose of the test. Most frequently included were descriptions of the conditions detected by the test, and the appropriate patients for testing. Nearly one half of the pamphlets included some statement about the accuracy of the test, but most of these did not specify whether their statements referred to sensitivity, specificity, or predictive value. Overall, pamphlets tended to contain information that would aid in determining a patient's eligibility for a genetic test, but did not contain sufficient information about the tests themselves. Our results suggest that several critical elements need to be added to enhance informed choices by patients and physicians.

Prenatal screening for cystic fibrosis carriers: does the method of testing affect the longer-term understanding and reproductive behaviour of women?

A comparative study of women who underwent prenatal cystic fibrosis (CF) carrier screening by either the 'two-step method' or the 'couple method' was carried out 2-4 years after testing. Recall of the screening test and test result, understanding of the implications of the test result, and reproductive intentions and behaviour were compared. Women screened by the two-step method were significantly better informed on the genetic implications of the test result and the significance of being a single gene carrier than their couple screen counterparts. Regardless of the method of screening, a majority of those who had received a negative test result erroneously believed that they were definitely not a carrier. However, women who intended having further children were significantly more likely to understand correctly that a negative test result meant that they were unlikely to be a CF carrier. The method of testing had no influence on reproductive intentions or behaviour. Differences in emphasis, content and presentation of pre-screening information and counselling between the two methods of screening are identified. Reasons for variation in the long-term understanding between women screened by the two methods are discussed.

The uptake and acceptability to patients of cystic fibrosis carrier testing offered in pregnancy by the GP

OBJECTIVE

To determine the uptake and acceptability of cystic fibrosis (CF) carrier testing when offered to women at the first antenatal booking appointment by their general practitioner.

SETTING

Eight-general practices in the north west region with a combined patient list size of 42000.

DESIGN

Offer of carrier screening at first antenatal booking appointment to pregnant women below 14 weeks' gestation; women accepting were alternately allocated to either couple testing (with full disclosure) or stepwise testing:

SUBJECTS

Six hundred and twenty three women were offered CF carrier testing.

MAIN OUTCOME MEASURES

(1) Acceptance of the offer of CF carrier testing. (2) Acceptability of the test to women following screening, evaluated through (i) postal questionnaire, (ii) semistructured interview.

RESULTS

Five hundred and twenty-nine (84.9%) women accepted the test; the level of uptake varied across the eight practices (range 11-99%). In 26/249 (10%) couple tests no paternal sample was provided. When asked what had influenced their decision to be tested, 59/377 (16%) women did not refer to CF in their answers and six (2%) said that they did not feel they could refuse the test. After receiving their results, 368/379 (97%) women felt that they had made the right decision to be tested, but two carriers and three non-carriers had felt unhappy about testing. Couple testing with full disclosure was associated with lower anxiety levels two weeks after receiving the result for the pregnancy than stepwise testing and 82/278 (29%) non-carriers believed that they had no residual risk in relation to CF.

CONCLUSIONS

The response from women accepting CF carrier testing was largely positive but a minority of women expressed concern about the test and the way it was offered and a substantial proportion of women were falsely reassured by their "negative" result. Higher levels of acceptance tended to occur in the practices which offered the test there and then rather than giving couples more time to decide about testing. Some women appeared to have accepted the test because of a belief in the importance of testing in pregnancy rather than because of the disease in question.

PCR-based screening for cystic fibrosis carrier mutations in an ethnically diverse pregnant population

As the most common lethal autosomal recessive disorder in North America, cystic fibrosis (CF) is an obvious candidate for general population carrier screening. Although the identification of the causative gene has made detection of asymptomatic carriers possible, the extreme heterogeneity of its mutations has limited the sensitivity of the available DNA screening tests and has called into question their utility when they are applied to patients with no family history of the disease. The purpose of this study was to determine the technical feasibility, patient acceptance and understanding, and psychosocial impact of large-scale CF carrier screening in an ethnically diverse pregnant population. A total of 4,739 pregnant women attending prenatal clinics located in both an academic medical center and a large HMO were invited in person to participate. Of this group, 3,543 received CF instruction and assessments of knowledge and mood, and 3,192 underwent DNA testing for the six most common CF mutations, by means of a noninvasive PCR-based reverse-dot-blot method. Overall participation rates (ranging from 53% at the HMO to 77% at the academic center) and consent rates for DNA testing after CF instruction (>98%) exceeded those of most other American studies. The PCR-based screening method worked efficiently on large numbers of samples, and 55 carriers and one at-risk couple were identified. Understanding of residual risk, anxiety levels, and overall satisfaction with the program were acceptable across all ethnic groups. Our strategy of approaching a motivated pregnant population in person with a rapid and noninvasive testing method may provide a practical model for developing a larger CF screening program targeting appropriate high-risk groups at the national level, and may also serve as a paradigm for population-based screening of other genetically heterogeneous disorders in the future.

Carrier screening for cystic fibrosis in primary care: evaluation of a project in South Wales. The South Wales Cystic Fibrosis Carrier Screening Research Team

Population carrier screening for cystic fibrosis (CF) was offered to all patients aged 16-45 in one general practice in South Wales, excluding those in couples with a current pregnancy. Out of 1553 patients in this group, 481 subjects were tested, giving an overall uptake rate of more than 30%. The rate of uptake varied with the mode of invitation. Twenty-six carriers were identified, giving a prevalence of identified carriers of 5.4% (1 in 18.5) for those with no family history of CF. A further 18 carriers were identified by cascade testing of these 26. We describe the practical difficulties encountered in setting up this programme in primary care in South Wales. Questionnaires were administered or distributed to all subjects before and after testing. The response rate for the pre-test questionnaire was 95%, and 40-50% for the post-test questionnaires. These showed that, at 3 months post-test, 1 in 4 screen-negative subjects did not appreciate that they had a residual risk of being a carrier. At the same time, 15% of this group thought that there was a 1 in 4 chance of a child being affected if one parent was screen-positive (carried an identified mutation) and the other was screen-negative, and 40% thought there was no risk. Anxiety in relation to testing did not appear to be a major problem, although individual patterns of response to carrier status varied widely and more sensitive indicators of psychosocial impact of genetic tests are required. A pilot study of couple screening showed that this approach is unlikely to be useful in primary care, although we did not assess couple testing during pregnancy. For any programme of CF carrier screening to be established in primary care, it will be necessary to involve the primary care team from the earliest planning stage, so that the opportunity costs, training needs and other costs of the programme can be fully resourced.

Outcomes and process in genetic counselling

Although it may be simple to evaluate some elements of clinical genetics, it is difficult to evaluate genetic counselling. We review previous studies of the outcomes of genetic counselling; although the methods used may be valid in research studies, there are practical and ethical difficulties in applying them to the measurement of clinical effectiveness in standard practice. No simple measures of outcomes would be suitable. Research evidence will be helpful in deciding what services it is appropriate to offer, and the quality of a service can then be assured by assessing the quality of the clinical process in three ways: 1) adherence to agreed protocols and standards of care; 2) peer review and audit of clinical activity; and 3) ongoing review of the satisfaction of clients and referring physicians with the service. The assessment of client satisfaction will need to be a sophisticated form of retrospective satisfaction with the service provided, and such a scheme has yet to be fully developed.

Cystic fibrosis carrier population screening in the primary care setting

To determine the receptivity of prenatal care providers and their patients to carrier testing for cystic fibrosis (CF), we offered free carrier screening, followed by genetic counseling of carriers, to all prenatal care providers in Rochester, NY, for all their female patients of reproductive age, pregnant or not. Of 124 prenatal care providers, only 37 elected to participate, but many of these offered screening only to pregnant women. The acceptance rate among pregnant women was approximately 57%. The most common reasons for accepting screening were to obtain reassurance (50.7%) and to avoid having a child with CF (27.8 %). The most common reasons for declining screening were not intending to terminate a pregnancy for CF (32.4%) and believing that the chance of having a CF child was very low (32.2%). Compared with decliners, acceptors were more likely to have no children, regarded having a child with CF as more serious, believed themselves more susceptible to having such a child, knew more about CF, would be more likely to terminate a pregnancy if the fetus were shown to have CF, and more strongly supported offering CF screening to women of reproductive age. Of 4,879 women on whom results were obtained, 124 were found to be carriers. Of these 124 carriers, the partners of 106 were tested. Of the five at-risk couples, four requested prenatal diagnosis and one requested neonatal diagnosis. No woman found to be a carrier whose partner tested negative requested prenatal diagnosis. Except for the imperfect knowledge of those testing negative, none of the adverse outcomes predicted for CF carrier testing in the general population were observed in this study.

Psychological impact of population-based carrier testing for cystic fibrosis: 3-year follow-up. UK Cystic Fibrosis Follow-Up Study Group

BACKGROUND

The objective of this study was to show the long-term psychological effects of population-based screening for cystic fibrosis.

METHODS

The sample comprised all carriers (n = 435) and, for each carrier, two matched screen-negative individuals (n = 870) detected during screening programmes for cystic fibrosis in the general population and in antenatal populations carried out a median of 3 years earlier in six UK centres. Questionnaires were sent to all eligible participants, with reminders sent to non-responders. The main endpoints were understanding of test results, degree of anxiety, perceptions of health, and reproductive intentions, and behaviour.

FINDINGS

746 (62%) of 1201 questionnaires were returned. Recall of the meaning of test results was accurate in 225 (80%) of 280 carriers but only 200 (43%) of 466 screen-negative individuals. 46 (16%) of 280 proven carriers believed that their result meant that they were only likely, rather than definitely, to be a carrier; 232 (50%) of 466 of those with a screen-negative result erroneously believed that the result meant that they were definitely not carriers. There was no significant difference between carriers and screen-negative individuals in degree of general anxiety, although 16% of carriers reported feeling worried about their test results. Carriers had a poorer perception of their current health than did non-carriers, even though they had been told that carrier status confers no disadvantages to their own health. There were no differences between carriers and screen-negative individuals in reproductive intentions or behaviour.

INTERPRETATION

We have shown that in the long-term, retention of the meaning of test results from cystic fibrosis screening is poor. Further research is needed to improve the performance of test-related counselling programmes to ensure that the main objectives of these programmes, to provide information on carrier status and to allow informed reproductive decisions, are met.

The CF carrier status is not associated with a diminished self-concept or increased anxiety: results of psychometric testing after at least 1 year

To evaluate whether the CF carrier status has any lasting effect on anxiety and on self-concept at least 1 year after the disclosure of the test result, an in-depth interview and additional psychological tests were administered in a group of adults who participated in a previous study which suggested a slight stigmatizing effect of the CF carrier status. Besides carrier status, the role of a second factor-degree of relationship-was investigated. Analysis of Variance (MANOVA or ANOVA) revealed no effect on state and trait anxiety (STAI) and almost no effect on the six subscales of the Tennessee Self-Concept Scale. The absence of a lasting negative effect of the CF carrier status on anxiety and self-concept is a very important finding. Nevertheless, an intriguing significant interaction effect was found: the group of sibs carrying the CF gene felt less integrated in the family than the group of non-carrier sibs. This effect of carrier status was not found in the more distant relatives. It is important to pay sufficient attention to this problem during genetic counseling when brothers or sisters of a CF patient receive a test result.

Prenatal screening for cystic fibrosis: 5 years' experience reviewed

BACKGROUND

Although several programmes of prenatal screening for cystic fibrosis have been completed and reported, there are still uncertainties about rates of take up and also about the action of parents identified as having a one-in-four risk of an affected child. I report 5 years' experience with the two-step and couple models of prenatal screening of cystic fibrosis.

METHODS

Screening has been available at two antenatal clinics in Edinburgh, UK, since January, 1992, first on a research basis and then routinely. 25,000 couples have been screened.

FINDINGS

Take-up rates for the two-step and couple models of delivery are very similar at about 70%. Take-up rates did not change when screening moved from a research to a routine service. Of 22 high-risk couples identified entirely through screening, 20 (91%) opted for prenatal diagnosis. Four couples returned for second and two for third monitored pregnancies. In all eight cases where affected fetuses were identified, pregnancy was terminated.

INTERPRETATION

These data remove one of the few remaining obstacles to a general implementation of prenatal screening for cystic fibrosis.

Carrier screening for cystic fibrosis

A number of different models of CF carrier screening have now been tested in pilot trials. Apart from opportunistic and cascade testing (which are strictly speaking not true forms of screening), the major programmes have been directed either to young adults in primary care or to pregnant women in antenatal clinics. Only in the latter form of screening has sufficient data been collected to allow conclusions to be reached on the optimum mode of delivery. It seems very probable that when CF carrier screening passes into routine service, it will be the antenatal couple model that is used.

A stigmatizing effect of the carrier status for cystic fibrosis?

The emotional impact of carrier detection for CF was assessed in a group of adults tested before 1992. Of the 200 adults who received a mailed questionnaire, 70% participated. One third were CF gene carriers. The Health Orientation Scale (HOS) was used to evaluate perceived feelings about three situations: (a) How would you describe your feelings about yourself when you consider your test result? (b) How do you think most people feel when they are told that they carry the CF gene? (c) How do you think most people feel when they are told that they do not carry the CF gene? Comparing the profiles of CF carriers and non-carriers, we found that carriers had significantly less positive feelings about themselves than non-carriers. Carriers as well as non-carriers attribute significantly more negative feelings to most carriers of the CF gene than to most non-carriers. Moreover, carriers of the Cf gene attribute more negative feelings to other CF carriers than to themselves. Analysis of variance revealed a significant effect of carrier status on self-description, as well as a significant effect of carrier status and degree of kinship with a CF patient on feelings attributed to most carriers. Although these results suggest some danger of stigmatization of CF carriers, the cognitive bias of 'illusory superiority' seems to counterbalance some of its effects.

Cascade testing for the identification of carriers of cystic fibrosis

It has been suggested that cascade testing, in which relatives of a person affected with cystic fibrosis (CF) are tested for carrier status, is preferable to screening individuals in the general population. This idea was examined by calculating the number of relatives requiring testing, assuming that it is necessary to identify all those of reproductive age no more distantly related to the proband than second cousins. Two hypothetical programmes were used, in each of which only blood relatives of an affected proband were tested and subsequent analysis applied to relatives of those with a positive result. If started in the grandparental generation, cascade testing of about 28 relatives for each proband would detect 86.4% of carriers in the family. If only carried out for the parental generation and their descendants, testing of about 35 relatives for each proband would detect 92.1% of carriers in the family. If cascade testing were restricted to the second cousin level, however, these programmes would only detect between 8 and 24% of all carrier couples. This contrasts with the 50% detection rate that has already been demonstrated for antenatal CF screening.

Antenatal screening for cystic fibrosis: a trial of the couple model

OBJECTIVE

To assess the delivery and acceptability of antenatal couple screening for cystic fibrosis. Carrier status was notified only when both members of a partnership had cystic fibrosis alleles and therefore a one in four risk of having an affected child.

DESIGN

Mouthwash samples were tested when both partners participated. Results were returned only to positive couples.

SETTING

Two large maternity hospitals in Edinburgh.

SUBJECTS

Screening was offered to all couples who booked at one of the two hospitals.

MAIN OUTCOME MEASURES

(a) The take up of screening, carriers and carrier couples identified, take up of prenatal diagnosis, and numbers of affected fetuses detected; (b) questionnaire measures of patient satisfaction and stress.

RESULTS

Screening was offered to 8536 couples. 714 (8.4%) were regarded as ineligible, usually because of late booking or absence of a partner. 1900 (24.3%) of the remainder declined screening. Among the 5922 screened couples, four tested positive--that is, both partners were cystic fibrosis heterozygotes. All four elected to have prenatal diagnosis. There were three terminations of pregnancy because of an affected fetus, one couple having two successive pregnancies with affected fetuses. The participation rate was 76% for eligible couples (5922/7822) and 69% for all couples (5922/8536). Only 89 screened couples (1.5%) requested information on individual carrier status. No anxiety was detected among a cohort of the screened population, and 99% of questioned participants expressed satisfaction with the concept of couple screening.

CONCLUSIONS

Antenatal couple screening is a satisfactory and acceptable way of screening for cystic fibrosis and has been adopted as routine in the two trial hospitals.