A systematic review of the factors associated with interest in predictive genetic testing for obesity, type II diabetes and heart disease

Advancing the communication of genetic risk for cardiometabolic diseases: a critical interpretive synthesis

BACKGROUND

Genetics play an important role in risk for cardiometabolic diseases-including type 2 diabetes, cardiovascular disease and obesity. Existing research has explored the clinical utility of genetic risk tools such as polygenic risk scores-and whether interventions communicating genetic risk information using these tools can impact on individuals' cognitive appraisals of disease risk and/or preventative health behaviours. Previous systematic reviews suggest mixed results. To expand current understanding and address knowledge gaps, we undertook an interpretive, reflexive method of evidence synthesis-questioning the theoretical basis behind current interventions that communicate genetic risk information and exploring how the effects of genetic risk tools can be fully harnessed for cardiometabolic diseases.

METHODS

We obtained 189 records from a combination of database, website and grey literature searches-supplemented with reference chaining and expert subject knowledge within the review team. Using pre-defined critical interpretive synthesis methods, quantitative and qualitative evidence was synthesised and critiqued alongside theoretical understanding from surrounding fields of behavioural and social sciences.

FINDINGS

Existing interventions communicating genetic risk information focus predominantly on the "self", targeting individual-level cognitive appraisals, such as perceived risk and perceived behavioural control. This approach risks neglecting the role of contextual factors and upstream determinants that can reinforce individuals' interpretations of risk. It also assumes target populations to embody an "ascetic subject of compliance"-the idea of a patient who strives to comply diligently with professional medical advice, logically and rationally adopting any recommended lifestyle changes. We developed a synthesising argument-"beyond the ascetic subject of compliance"-grounded in three major limitations of this perspective: (1) difficulty applying existing theories/models to diverse populations, (2) the role of familial variables and (3) the need for a life course perspective.

CONCLUSIONS

Interventions communicating genetic risk information should account for wider influences that can affect individuals' responses to risk at different levels-including through interactions with their family systems, socio-cultural environments and wider health provision.

PROTOCOL REGISTRATION

PROSPERO CRD42021289269.

Acceptability of predictive testing for ischemic heart disease in those with a family history and the impact of results on behavioural intention and behaviour change: a systematic review

BACKGROUND

Tests to predict the development of chronic diseases in those with a family history of the disease are becoming increasingly available and can identify those who may benefit most from preventive interventions. It is important to understand the acceptability of these predictive approaches to inform the development of tools to support decision making. Whilst data are lacking for many diseases, data are available for ischemic heart disease (IHD). Therefore, this study investigates the willingness of those with a family history of IHD to take a predictive test, and the effect of the test results on risk-related behaviours.

METHOD

Medline, EMBASE, PsycINFO, LILACS and grey literature were searched. Primary research, including adult participants with a family history of IHD, and assessing a predictive test were included. Qualitative and quantitative outcomes measuring willingness to take a predictive test and the effect of test results on risk-related behaviours were also included. Data concerning study aims, participants, design, predictive test, intervention and findings were extracted. Study quality was assessed using the Standard Quality Assessment Criteria for Evaluating Research Papers from a Variety of Fields and a narrative synthesis undertaken.

RESULTS

Five quantitative and two qualitative studies were included. These were conducted in the Netherlands (n = 1), Australia (n = 1), USA (n = 1) and the UK (n = 4). Methodological quality ranged from moderate to good. Three studies found that most relatives were willing to take a predictive test, reporting family history (n = 2) and general practitioner (GP) recommendation (n = 1) as determinants of interest. Studies assessing the effect of test results on behavioural intentions (n = 2) found increased intentions to engage in physical activity and smoking cessation, but not healthy eating in those at increased risk of developing IHD. In studies examining actual behaviour change (n = 2) most participants reported engaging in at least one preventive behaviour, particularly medication adherence.

CONCLUSION

The results suggests that predictive approaches are acceptable to those with a family history of IHD and have a positive impact on health behaviours. Further studies are needed to provide a comprehensive understanding of predictive approaches in IHD and other chronic conditions.

From the prodromal stage of multiple sclerosis to disease prevention

A prodrome is an early set of signs or symptoms that indicate the onset of a disease before more typical symptoms develop. Prodromal stages are well recognized in some neurological and immune-mediated diseases such as Parkinson disease, schizophrenia, type 1 diabetes mellitus and rheumatoid arthritis. Emerging evidence indicates that a prodromal stage exists in multiple sclerosis (MS), raising the possibility of intervention at this stage to delay or prevent the development of classical MS. However, much remains unclear about the prodromal stage of MS and considerable research is needed to fully characterize the prodrome and develop standardized criteria to reliably identify individuals with prodromal MS who are at high risk of progressing to a diagnosis of MS. In this Roadmap, we draw on work in other diseases to propose a disease framework for MS that incorporates the prodromal stage, and set out key steps and considerations needed in future research to fully characterize the MS prodrome, identify early disease markers and develop standardized criteria that will enable reliable identification of individuals with prodromal MS, thereby facilitating trials of interventions to slow or stop progression beyond the prodrome.

Public perceptions of predictive testing for rheumatoid arthritis compared to breast cancer and early-onset Alzheimer's disease: a qualitative study

BACKGROUND

There is increasing research focus on prediction and prevention of rheumatoid arthritis (RA). Information about risk of RA is increasingly available via direct-to-consumer testing. However, there is limited understanding of public perceptions around predictive testing for RA. This study explores public perceptions of predictive testing for RA in comparison to breast cancer (BC) and early-onset Alzheimer's disease (AD).

METHODS

Four focus groups with 21 members of the public were conducted using hypothetical vignettes about predictive testing for each disease. Transcripts of focus group proceedings were analysed inductively using thematic analysis.

RESULTS

Thematic analysis of the data produced three key themes: decision-making factors, consequences, and consumer needs. Factors suggested that might influence decision-making about predictive testing included family history, fear, and perceived severity and treatability of the illness. RA was perceived to be less severe and more treatable than BC/AD. Potential consequences of predictive testing across all diseases included lifestyle modification, planning for the future and discrimination by employers or insurers. Predictive testing for RA was perceived to have less potential for negative psychological consequences than other diseases. Participants highlighted that individuals undertaking predictive testing should be signposted to appropriate support services and receive information on the accuracy of predictive testing. It was suggested that strategies to mitigate concerns regarding communication and confidentiality of risk results are required.

CONCLUSIONS

The findings of this study reflect public misunderstandings regarding RA that may impact the uptake of and responses to predictive testing, and key informational needs of individuals considering a predictive test. Predictive strategies should be accompanied by awareness-raising initiatives and informational resources.

"I think that a brief conversation from their provider can go a very long way": Patient and provider perspectives on barriers and facilitators of genetic testing after ovarian cancer

OBJECTIVE

Identify predisposing, enabling, and reinforcing factors impacting genetic counseling/testing among ovarian cancer patients guided by Green and Kreuter's PRECEDE-PROCEED model.

METHODS

Gynecologic oncology providers (N = 4), genetic counselors (N = 4), and ovarian cancer patients (N = 9) completed semi-structured qualitative interviews exploring participants' knowledge of and experiences with genetic counseling/testing. Interviews were audio recorded, transcribed verbatim, and analyzed using inductive content analysis by two independent raters.

RESULTS

Thematic analysis identified predisposing, enabling, and reinforcing factors impacting referral for and uptake of genetic counseling/testing. Predisposing factors included participant's knowledge, beliefs, and attitudes related to genetic counseling/testing. Both patients and providers also cited that insurance coverage and out-of-pocket cost are major concerns for ovarian cancer patients considering genetic testing. Finally, both patients and providers emphasized that genetic counseling/testing would provide additional information to an ovarian cancer patient. While providers emphasized that genetic testing results were useful for informing a patient's personal treatment plan, patients emphasized that this knowledge would be beneficial for their family members.

CONCLUSION

Barriers to genetic testing for ovarian cancer patients exist at multiple levels, including the patient (e.g., knowledge, attitudes), the provider (e.g., workload, availability of services), the institution (e.g., difficulty with referrals/scheduling), and the healthcare system (e.g., insurance/cost). Interventions aiming to increase genetic testing among ovarian cancer patients will likely need to target multiple levels of influence. Future quantitative studies are needed to replicate these results. This line of work will inform specific multilevel intervention strategies that are adaptable to different practice settings, ultimately improving guideline concordant care.

Health orientation and individual tendencies of a sample of Italian genetic testing consumers

Background

Over the last decade, genetic testing (GT) had markedly spread in European countries and struggled the debate concerning the psychological effects on the population. The aim of this study was to investigate the individual tendencies of GT consumers in a sample of Italian citizens.

Methods

A total of 152 Italian clients from GenomaLab, a private genetic company, were enrolled from February 2016 to September 2018 and completed an ad hoc survey.

Results

Results showed that GT consumers were motivated to preserve their well‐being, they felt responsible for their health, they were neither pessimistic nor optimistic toward negative occurrences, and poorly inclined to take high risks in their lives. Participants who had suffered from a disease in the past appear to be less tolerant to the uncertainty for future negative events.

Conclusion

Our results depict Italian GT consumers as health‐oriented, focused on prevention, who do not have a pessimistic perception of their condition but do not like to “bet” on their health, and probably their intention (and belief) is to acquire genetic information in order to reduce uncertainty and increase their decision‐making “power” related to their health. Taken together, all these results contribute to describe the population of GT users in European countries, to regulate the provision of GT results and to entail the communication of genetic risk information based on a consumers’ personal profile.

Preferences of Patients and At-risk Individuals for Preventive Approaches to Rheumatoid Arthritis

Effective treatments for rheumatoid arthritis (RA) are available and can lead to remission for some patients, but most patients remain on potentially toxic and expensive medications in the long term. Interest is increasingly turning to the disease phases preceding the development of RA that represent opportunities for preventive interventions. At-risk target populations include individuals with genetic and environmental risk factors, those who have developed systemic autoimmunity, and those who have developed clinically suspect symptoms (eg, arthralgias without synovitis, or an early arthritis). Ongoing prospective studies will inform the development of increasingly accurate predictive tools to identify individuals at risk of developing RA. Furthermore, a range of preventive approaches has been suggested, including lifestyle modification (eg, smoking cessation) and pharmacologic interventions (eg, hydroxychloroquine, methotrexate, abatacept, rituximab) that are currently the subject of randomized controlled trials. As prediction and prevention of RA evolve, it is increasingly likely that individuals at risk (including asymptomatic individuals) may be faced with complex decisions about whether to accept assessment of their risk status or to take a preventive intervention associated with risk of serious adverse events and uncertain benefit. Acceptance of preventive medication in other contexts can be low. For example, <25% of women at high risk of breast cancer are willing to take preventive hormonal treatments. Actual uptake is lower still. Patients' beliefs and preferences predict treatment uptake and adherence. Before the dream of preventing RA can become reality, health care providers need to understand the perspectives of individuals in the target population and to identify barriers and facilitators for this approach. This commentary reviews what is currently known about the perspectives of patients and individuals at risk about predictive and preventive approaches for RA and identifies gaps to be addressed to inform the development of efficient preventive strategies.

Factors affecting breast cancer patients' need for genetic risk information: From information insufficiency to information need

Information-seeking models typically focus on information-seeking behaviors based on individuals' interest in information, because their current level is perceived to be insufficient. In the context of genetic risk information (GRI), however, information insufficiency is difficult to measure and thus can limit understanding of information behavior in the context of GRI. We propose that an individual's need for information might be a more direct and conceptually clearer alternative to predicting their information-seeking behavior. To test this hypothesis, this study investigates the extent to which previously identified factors affecting interest in GRI are also predictors of need for GRI among women diagnosed with breast cancer at the age of 40 or younger (N = 1,069). As hypothesized, there was a positive association between interest in and need for GRI. Furthermore, hypothesized factors of numeracy, information orientation, and genetic knowledge were significant predictors of increased interest in and need for GRI. In contrast, hypothesized factors of genetic worry and genetic causal belief predicted increased interest in GRI only, while genetic self-efficacy predicted increased need for GRI only. As hypothesized, BRCA status significantly moderated associations between informational norm and both interest in and need for GRI. Collectively, the findings support inclusion of need for GRI in theoretical information-seeking models in the context of genomic risk.

Racial and ethnic differences in knowledge and attitudes about genetic testing in the US: Systematic review

Precision medicine has grown over the past 20 years with the availability of genetic tests and has changed the one-size-fits-all paradigm in medicine. Precision medicine innovations, such as newly available genetic tests, could potentially widen racial and ethnic disparities if access to them is unequal and if interest to use them differs across groups. The objective of this systematic review was to synthesize existing evidence on racial and ethnic differences in knowledge of and attitudes toward genetic testing among adult patients and the general public in the US, focusing on research about the use of genetic testing in general, not disease-specific tests. Twelve articles published in 1997-2017 met inclusion and exclusion criteria, with 10 including knowledge variables and seven including attitude variables. Studies found consistent patterns of lower awareness of genetic testing in general among non-Whites compared to Whites, lower factual knowledge scores among Blacks and Hispanics/Latinos, and mixed findings of differences in awareness of direct-to-consumer (DTC) genetic testing or the term precision medicine. Blacks, Hispanics/Latinos, and non-Whites generally had more concerns about genetic testing than Whites. The findings suggest that patients and the general public need access to culturally appropriate educational material about the use of genetic testing in precision medicine.

Associations of perceived norms with intentions to learn genomic sequencing results: Roles for attitudes and ambivalence

OBJECTIVE

Genomic sequencing is becoming increasingly accessible, highlighting the need to understand the social and psychological factors that drive interest in receiving testing results. These decisions may depend on perceived descriptive norms (how most others behave) and injunctive norms (what is approved of by others). We predicted that descriptive norms would be directly associated with intentions to learn genomic sequencing results, whereas injunctive norms would be associated indirectly, via attitudes. These differential associations with intentions versus attitudes were hypothesized to be strongest when individuals held ambivalent attitudes toward obtaining results.

METHOD

Participants enrolled in a genomic sequencing trial (n = 372) reported intentions to learn medically actionable, nonmedically actionable, and carrier sequencing results. Descriptive norms items referenced other study participants. Injunctive norms were analyzed separately for close friends and family members. Attitudes, attitudinal ambivalence, and sociodemographic covariates were also assessed.

RESULTS

In structural equation models, both descriptive norms and friend injunctive norms were associated with intentions to receive all sequencing results (ps < .004). Attitudes consistently mediated all friend injunctive norms-intentions associations, but not the descriptive norms-intentions associations. Attitudinal ambivalence moderated the association between friend injunctive norms (p ≤ .001), but not descriptive norms (p = .16), and attitudes. Injunctive norms were significantly associated with attitudes when ambivalence was high, but were unrelated when ambivalence was low. Results replicated for family injunctive norms.

CONCLUSIONS

Descriptive and injunctive norms play roles in genomic sequencing decisions. Considering mediators and moderators of these processes enhances ability to optimize use of normative information to support informed decision making. (PsycINFO Database Record

The price of whole-genome sequencing may be decreasing, but who will be sequenced?

AIM

Since whole-genome sequencing (WGS) information can have positive and negative personal utility for individuals, we examined predictors of willingness to pay (WTP) for WGS.

PATIENTS & METHODS

We surveyed two independent populations: adult patients (n = 203) and college seniors (n = 980). Ordinal logistic regression models were used to characterize the relationship between predictors and WTP.

RESULTS

Sex, age, education, income, genomic knowledge and knowing someone who had genetic testing or having had genetic testing done personally were associated with significantly higher WTP for WGS. After controlling for income and education, males were willing to pay more for WGS than females.

CONCLUSION

Differences in WTP may impact equity, coverage, affordability and access, and should be anticipated by public dialog about related health policy.

Recent progress in genetics, epigenetics and metagenomics unveils the pathophysiology of human obesity

In high-, middle- and low-income countries, the rising prevalence of obesity is the underlying cause of numerous health complications and increased mortality. Being a complex and heritable disorder, obesity results from the interplay between genetic susceptibility, epigenetics, metagenomics and the environment. Attempts at understanding the genetic basis of obesity have identified numerous genes associated with syndromic monogenic, non-syndromic monogenic, oligogenic and polygenic obesity. The genetics of leanness are also considered relevant as it mirrors some of obesity's aetiologies. In this report, we summarize ten genetically elucidated obesity syndromes, some of which are involved in ciliary functioning. We comprehensively review 11 monogenic obesity genes identified to date and their role in energy maintenance as part of the leptin-melanocortin pathway. With the emergence of genome-wide association studies over the last decade, 227 genetic variants involved in different biological pathways (central nervous system, food sensing and digestion, adipocyte differentiation, insulin signalling, lipid metabolism, muscle and liver biology, gut microbiota) have been associated with polygenic obesity. Advances in obligatory and facilitated epigenetic variation, and gene-environment interaction studies have partly accounted for the missing heritability of obesity and provided additional insight into its aetiology. The role of gut microbiota in obesity pathophysiology, as well as the 12 genes associated with lipodystrophies is discussed. Furthermore, in an attempt to improve future studies and merge the gap between research and clinical practice, we provide suggestions on how high-throughput '-omic' data can be integrated in order to get closer to the new age of personalized medicine.

Preferences for the provision of whole genome sequencing services among young adults

Objectives

As whole genome sequencing (WGS) becomes increasingly available, clinicians will be faced with conveying complex information to individuals at different stages in life. The purpose of this study is to characterize the views of young adults toward obtaining WGS, learning different types of genomic information, and having choice about which results are disclosed.

Methods

A mixed-methods descriptive study was conducted with a diverse group of 18 and 19-years-olds (N = 145). Participants watched an informational video about WGS and then completed an online survey.

Results

Participants held a positive attitude toward obtaining WGS and learning about a range of health conditions and traits. Increased interest in learning WGS information was significantly associated with anticipated capacity to handle the emotional consequences if a serious risk was found (β = 0.13, P = .04). Young adults wanted the ability to choose what types of genomic risk information would be returned and expressed decreased willingness to undergo WGS if clinicians made these decisions (t(138) = -7.14, P <.01). Qualitative analysis showed that young adults emphasized procedural factors in WGS decision-making and that perceived health benefits of WGS had a substantial role in testing preferences and anticipated usage of WGS results.

Conclusions

Clinicians are likely to encounter enthusiasm for obtaining WGS results among young adults and may need to develop strategies for ensuring that this preference is adequately informed.

Public Views on Genetics and Genetic Testing: A Survey of the General Public in Belgium

AIMS

To explore the views of the Belgian public on various topics surrounding genetics and genetic testing (GT).

MATERIALS AND METHODS

A written questionnaire was administered to visitors of the annual cartoon festival in Knokke-Heist, Belgium, during the summer of 2014. The main theme of the festival was challenges and progress in human genetics and it was attended by more than 100,000 visitors.

RESULTS

The survey was completed by 1182 respondents, resulting in a demographically diverse sample with a mean age of 48.5 years. Our respondents expressed moderate interest in predictive GT, with 39.1% willing to learn about their predisposition to diseases through GT and 49.5% indicating interest in getting tested exclusively for treatable/preventable diseases. We observed higher interest in GT for reproductive purposes, such as preconception screening for recessive disorders (53.8%) and prenatal GT (60.7%). A substantial minority (46.4%) of the respondents were worried that GT could further stigmatize people with disabilities, while 39.7% believed that carrier screening for recessive diseases would lead to an inferior image of people affected by them.

CONCLUSION

Paying due attention to the attitudes, beliefs, and concerns of the general public is important to ensure ethically sound and socially acceptable implementation of new genetic technologies.

Prevalence and screening for risk factors of type 2 diabetes in Rize, Nourtheast Turkey: findings from a population-based study

AIMS

We aimed to determine the prevalence of diagnosed and undiagnosed diabetes, risk factors affecting the healthy population, and factors that increase diabetes risk in the adult northeast Turkish population.

METHODS

Using population proportional cluster sampling, 930 adults were selected. After excluding people with diabetes, risk screening was conducted in the healthy population (n: 825) using the Information Form and FINDRISK questionnaire. Fasting venous blood and biochemical parameters were measured.

RESULTS

Prevalence of diabetes was 13.6% (new % 2.3), translating to approximately 44 thousand adults. Among the healthy population, 37.5% had high risk. Prevalence of not exercising (78.2%), obesity (36.1%), and hypertension (24.5%) were high. Predictors of risk of diabetes were aging (OR 1.09), low education (OR 0.51), familial diabetes history (OR 15.27), not exercising (OR 0.41), obesity (OR 5.17), high waist circumference (OR 1.05), heart disease (OR 4.81), and hypertension (OR 2.60).

CONCLUSIONS

This study can stimulate early screening for cardiovascular diseases and hypertension and initiating aggressive treatments in people with high diabetes risk. In primary health services, number of doctors and nurses trained in diabetes should be increased and dieticians should be involved. People with high risk should receive lifestyle regulations training.