Carrier screening for cystic fibrosis in a prenatal setting

"Suddenly Having two Positive People who are Carriers is a Whole New Thing" - Experiences of Couples Both Identified as Carriers of Cystic Fibrosis Through a Population-Based Carrier Screening Program in Australia

A population-based CF carrier screening program was implemented in Victoria, Australia in 2006. This study explored the experiences of couples when both partners were identified as CF carriers. Between January 2006 and December 2010, 10 carrier couples were identified and invited to undertake a semi-structured interview. Nine interviews were conducted, seven couple interviews and two individual interviews. One couple declined to participate due to the recent termination of an affected pregnancy. Interviews were analyzed using inductive content analysis. All couples experienced surprise on learning their carrier couple result. The couples who were pregnant at the time of screening chose to have prenatal diagnosis, with the majority considering it to be the "next step." The two couples who had an affected pregnancy reported feelings of devastation and grief upon receiving their prenatal diagnosis result and terminated the pregnancy. All carrier couples were offered free genetic counseling, with only one couple declining the offer. Couples were unprepared for a positive carrier couple result. However, all the couples changed their reproductive behavior as a result of their carrier status. The results of this study have been used to inform the program and service offered to CF carrier couples particularly with respect to genetic counseling for reproductive decision making.

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.

Cystic Fibrosis Screening

The integration of universal cystic fibrosis screening in women's health has considerably altered the way we care for obstetric patients and likely will be the foundation for incorporating other genetic tests into routine women's health care. Prior to this change in the standard of care, screening for genetic disease was primarily limited to those individuals who had a personal or family history of the genetic condition or who belonged to a particular ethnic or racial group characterized by a high frequency of carrier and affected individuals. However, technological advances have resulted in facile and economic methodologies for detecting an increasing number of genetic mutations and in the realization that screening for common and uncommon disorders will likely be a not-too-distant-future part of routine health care. Programs that permit clinicians to properly implement genetic protocols and allow patients to make informed decisions about genetic screening and diagnostic tests are needed. The implementation of universal cystic fibrosis screening allows clinicians to recognize the benefits and pitfalls of genetic testing of the general population and encourages the development of programs that will effectively communicate genetic information to professionals and laity.

Factors affecting decisions to accept or decline cystic fibrosis carrier testing/screening: A theory-guided systematic review

PURPOSE

To assess factors affecting individuals' decision to accept or decline cystic fibrosis carrier testing/screening, as reported in studies published until December 2006. The Health Belief Model guided classification of each factor, and the studies' methodological quality was assessed.

METHODS

A three-stage search and retrieval process, alongside application of specific inclusion/exclusion criteria, yielded 40 studies (in 35 articles). For each reviewed study, authors abstracted and organized selected data into a matrix and assigned a methodological quality score.

RESULTS

The four most frequently identified acceptance factors included three Health Belief Model factors and one non-Health Belief Model factor: perceived benefits of undergoing cystic fibrosis carrier testing/screening, weaker perception of barriers to cystic fibrosis carrier testing/screening, fewer/no children or desiring children, and research-related factors (non-Health Belief Model factor construct). All four most frequent factors associated with declining testing were Health Belief Model factor constructs: perceived barriers to obtaining cystic fibrosis carrier testing/screening, parity, lack of knowledge, and weaker perception of benefits of undergoing cystic fibrosis carrier testing/screening. The average methodological quality of the studies was 10.2 (SD=3.2; range, 5-18 points).

CONCLUSIONS

The methodological and theoretical quality of this body of literature could be substantially improved if researchers employed theory-based approaches, tested (and reported) the validity/reliability of their own data, and employed multivariate statistical analyses and/or better controlled research designs. Improving the quality of future studies may allow better inferences regarding the relative contribution of each factor identified in this review to individuals' decision-making process.

A report of two linked studies of knowledge and attitudes to prenatal screening and testing in adults of reproductive age in Japan and the UK

BACKGROUND

prenatal screening for fetal abnormality is being offered routinely in many countries. The need for informed consent demands that the nature of screening is understood by prospective parents, but the opportunities for providing information early in pregnancy before decision-making may be limited.

OBJECTIVE

to assess the knowledge about, and attitudes to, prenatal screening in adults of reproductive age in two countries.

DESIGN

two groups of adults were surveyed using a specifically designed tool to assess knowledge about fetal abnormalities and potential screening tests, attitudes to screening and termination of pregnancy, and information required by parents before making decisions.

SETTING AND PARTICIPANTS

90 participants were surveyed in Japan, 72% of whom were pregnant or had a partner who was pregnant; 93 participants were surveyed in the UK, none of whom were pregnant. All respondents were aged between 18 and 45 years.

MEASUREMENTS

demographic data were collected and analysed. Frequencies were calculated for each questionnaire response. A series of t-tests and chi(2) tests were used to assess differences between the two groups. Free-text data were analysed using content analysis.

FINDINGS

overall knowledge of prenatal tests and the conditions for which screening is offered was low in both groups. Significant differences exist between the perception of the conditions for which screening or testing can be offered and the types of conditions that can actually be detected prenatally. Most respondents in both countries would consider termination of pregnancy for fetal abnormality. The information most frequently cited by respondents as important when deciding about testing were the chances of damage to the health of fetus, mother, or both.

KEY CONCLUSIONS

women and men of reproductive age in the groups studied are not well-prepared to make decisions about screening or testing in pregnancy.

IMPLICATIONS FOR PRACTICE

improvements in preconceptual education on prenatal screening and testing may be required to ensure prospective parents can make informed decisions in early pregnancy.

Population genetic screening programmes: principles, techniques, practices, and policies

This paper examines the professional and scientific views on the principles, techniques, practices, and policies that impact on the population genetic screening programmes in Europe. This paper focuses on the issues surrounding potential screening programmes, which require further discussion before their introduction. It aims to increase, among the health-care professions and health policy-makers, awareness of the potential screening programmes as an issue of increasing concern to public health. The methods comprised primarily the review of the existing professional guidelines, regulatory frameworks and other documents related to population genetic screening programmes in Europe. Then, the questions that need debate, in regard to different types of genetic screening before and after birth, were examined. Screening for conditions such as cystic fibrosis, Duchenne muscular dystrophy, familial hypercholesterolemia, fragile X syndrome, hemochromatosis, and cancer susceptibility was discussed. Special issues related to genetic screening were also examined, such as informed consent, family aspects, commercialization, the players on the scene and monitoring genetic screening programmes. Afterwards, these questions were debated by 51 experts from 15 European countries during an international workshop organized by the European Society of Human Genetics Public and Professional Policy Committee in Amsterdam, The Netherlands, 19-20, November, 1999. Arguments for and against starting screening programmes have been put forward. It has been questioned whether genetic screening differs from other types of screening and testing in terms of ethical issues. The general impression on the future of genetic screening is that one wants to 'proceed with caution', with more active impetus from the side of patients' organizations and more reluctance from the policy-makers. The latter try to obviate the potential problems about the abortion and eugenics issues that might be perceived as a greater problem than it is in reality. However, it seems important to maintain a balance between a 'professional duty of care' and 'personal autonomy'.

Newborn screening for cystic fibrosis

Early diagnosis of cystic fibrosis (CF) provides an opportunity to improve disease control and prevent early complications. Of patients with CF in the United States, 10% are identified early through newborn screening (including infants born in Colorado, Massachusetts, New Jersey, New York, Wisconsin, Wyoming, and parts of California, Connecticut, Pennsylvania, and Montana). Successful screening programs in these states have stimulated other states to consider adding CF screening to their newborn programs. Additionally, new technology permits expanded screening for numerous genetic conditions. Genetic screening, such as that used most frequently for CF, creates new challenges for the clinician, including atypical disease presentations and carrier detection. In this review, we examine the many advances in CF newborn screening and early care that were reported during the last few years.

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.