Perceived genetic knowledge, attitudes towards genetic testing, and the relationship between these among patients with a chronic disease

Abstract

Objective

Genetics increasingly permeate everyday medicine. When patients want to make informed decisions about genetic testing, they require genetic knowledge. This study examined the genetic knowledge and attitudes of patients with chronic diseases, and the relationship between both. In addition, patients were asked about their preferred source of genetic information.

Methods

Questionnaires were mailed to participants of a nationwide representative sample of patients with chronic diseases in the Netherlands (n = 1916).

Results

The response rate was 82% (n = 1496). Perceived genetic knowledge was low, particularly among older and lower educated patients. Attitudes towards genetics were rather positive, especially among younger and higher educated patients. Some concerns were also documented, mainly about the consequences of genetic testing for employment and taking insurance. Patients who perceived to have little knowledge found it difficult to formulate an opinion about genetic testing. Higher levels of genetic knowledge were associated with a more favourable attitude towards genetics. Chronic patients prefer to receive genetic information from their GP.

Conclusion

Chronic patients are ill prepared when they require genetic knowledge to make decisions regarding the treatment of their disease. This seems to result from a knowledge deficiency rather than from disagreement with the genetic developments.

Practice implications

When chronic patients are in need of information about genetics or genetic testing, their general practitioner should provide this.

Introduction

The recent completion of human genome sequencing [1] will fuel research aiming to identify genetic factors in the aetiology of disease [2]. Identification of such disease genes allows the development of genetic or DNA-tests to determine whether people are at risk of or affected by a disease [3], [4]. As the availability of these tests increases, genetics will slowly but surely permeate medical practice, and may one day become routine. Genetic insights have the potential to change the very conception of disease, and consequently clinical diagnosis and treatment [5]. This transformation has started the moment genetic testing was introduced, allowing diagnosis and treatment of disease even before its clinical manifestation. For example, genetic tests have enabled women with a genetic susceptibility to breast and ovarian cancer to decide on prophylactic oophorectomy or mastectomy [6].

Acknowledging the growing importance of genetics to western society, and particularly to health care, in 2001, the Netherlands Advisory Council for Science and Technology Policy stated that medicine could be expected to change from being disease-oriented to risk-oriented, and that this would eventually affect the entire health care system. Novel scientific knowledge about the human genome generates new medical insights, which will affect individuals who utilise health care services, and confront them with a new type of decision-making. How individuals handle such decisions depends on their knowledge, and on their view of human genetics and human genetics research. The capacity of individuals to make these decisions on the basis of general and disease-specific genetic information largely depends on successful communication of scientific information to the public [7]. In addition, a scientifically knowledgeable public is required for democratic participation in issues of science and technology, and tends to be more positively disposed towards these [8].

This raises the question what people actually know and think about genetics and DNA-testing. Hitherto, most studies investigated knowledge of and attitudes towards genetics in the general population, for instance of Finland [9], [10], [11], the United Kingdom [12], the Netherlands [13], [14] or Europe [8]. These studies show that the public have a reasonable understanding of the relationship between genes, heredity, and disease [7], [14]. Also, a higher level of knowledge has been associated with female gender, younger age, and higher socio-economic status [12], [13]. In general, genetics are seen as something positive and potentially beneficial for future medicine, particularly among younger and higher educated individuals [10], [13], [14]. On the other hand, there are concerns on the long-term effects of genetics and commercial misuse [8], [12], [14]. A higher level of knowledge seems to be associated with a more favourable attitude toward genetic testing, but also with being more critical [10], [12], although the direction of this connection may go both ways [8]. Individuals with a relative lack of genetic knowledge find it more difficult to formulate an opinion [9].

Unlike population-based studies (see above), studies investigating genetic knowledge and attitudes in patients usually concentrate on specific disease-related issues [15], [16], [17], [18]. The present study aimed to investigate knowledge and attitudes related to genetics and genetic testing in general, among patients with chronic illnesses (e.g., diabetes, heart disease, musculoskeletal disease). Once diagnosed, these patients must deal with their illness for the rest of their life, and often have to rely heavily on health care services [19], [20]. Thus, they become closely involved with issues of health and disease, which may translate into more knowledge. In addition, the role of genetics in chronic disease is rising because the number of patients with chronic diseases is growing [21], and genetic tests become increasingly available for chronic diseases [22]. The present study surveys perceived genetic knowledge and attitudes, and the relationship between these, in patients with chronic diseases. In addition, we asked these patients whether they had sought information about genetics and genetic testing, and from what source they would prefer to receive such information.