Expect Cultural Differences in Patient Views on Cancer

August 1, 1997

Today, more emphasis is being placed on quality of life assessment in the evaluation of the efficacy of medical care.[1,2] A new study, described below, along with other international quality of life studies, suggests that physicians and their patients may place different values on different health outcomes of treatment, depending on socioeconomic status and cultural milieu.

Today, more emphasis is being placed on quality of life assessment inthe evaluation of the efficacy of medical care.[1,2] A new study, describedbelow, along with other international quality of life studies, suggeststhat physicians and their patients may place different values on differenthealth outcomes of treatment, depending on socioeconomic status and culturalmilieu.

For some patients, the chance of extending survival may override allother considerations, while for others, a shorter life with higher qualitymay be more important. A new research method, known as quality assessment(described below), now allows the patient's value system to be quantifiedin such a way as to help the patient and physician come to a decision abouttreatment of advanced cancers.

How Patients View Quality of Life

The way patients view their quality of life depends not only on thephysical presence of a disease but also on the psychological and socialresponses to symptoms caused by that disease.[3] Cancer is an example ofa chronic disease whose treatment and prevention goals are to extend lifeexpectancy while improving patient quality of life.[4]

Patients' experience and evaluation of their cancer are known to varysignificantly according to patient characteristics such as age, gender,ethnicity, and socioeconomic status. Similarly, an individual's value andinterpretation of quality of life is largely determined by personal, interpersonal,and cultural aspects that make up a person's values, expectations, andperceptions.[5]

Because of the effect of different cultural backgrounds on the patient'sperception of quality of life, recent studies have focused on cross-culturalassessments of the impact of diseases. The two main types of internationalquality of life studies are described below, with examples of each.[7-11]

International Quality of Life Studies

The first type of international quality of life study evaluates comparisonsof quality of life assessments from subjects in different countries. Thesestudies show that performance is consistent within broad cultural groupsrepresentative of regionally and economically similar countries.

A review of combined data from several similar studies showed that participantsfrom up to 17 different countries gave similar ratings to most items relatingto various health states. The largest differ-ences were evident betweenratings given by the general public and those of physicians.[7]

In these studies, there is relatively more agreement for items thatexpress purely physical states and less agreement for items that reflectsocioemotional states that are more likely to be affected by cultural values.[7,8]

The second type of study compares opinions of people from two or morecountries on a given subject (eg, attitudes toward cancer). These studieshave found that within a broad cultural group, opinions do not vary significantlybetween countries. For example, in one such study, English, Italian, German,and Swedish speaking breast cancer patients showed concordance in theiropinions toward health states associated with cancer.[9]

Large differences have been observed, however, in the opinions of subjectsfrom Eastern and Western cultures. Cancer patients from the United States,for example, were shown to have different attitudes toward their diseasethan patients from Egypt and India,[10,11] findings attributed to differingcultural perspectives.

Utility Assessment

While it is important to qualitatively evaluate patient attitudes towardcancer, use of additional quantitative data can enhance comparisons betweengroups of patients. Such information, however, is often difficult to obtain.One method that has been widely used to quantitatively interpret patientattitudes toward various aspects of cancer is utility assessment.

A utility score is a quantitative measure of the strength of a person'spreference for a specified health outcome. Utility scores are measuredon a scale of 0 to 1, in which 0 represents death and 1 represents perfecthealth.

Typically, utility scores are determined by asking a series of questionsabout a health state to find out how much a person would be willing torisk to improve that health state. For example, patients may be asked howmuch time they would give up to improve quality of life. The point of indifferenceoccurs when the patient rates shortened life expectancy with perfect qualityof life the same as longer life expectancy with lower quality of life.

In an effort to assess the utility of health states related to cancerand its treatments, many studies have looked at responses to utility instrumentsfrom oncologists on behalf of their patients.

In one case study, 33 physicians from 14 different (primarily European)countries were presented with scenarios of alternative health states associatedwith cis-platinum chemotherapy. The physicians were asked to estimate patientprefer-ences for the likely health states associated with the cancer chemotherapyand chemotherapy-related toxicities. This is one of the first studies toconsider international utility assessments.[12]

The toxicities examined in this study were neurotoxicity and nephrotoxicity,which are the most common and most severe side effects of cis-platinumchemotherapy. For each scenario corresponding to a particular toxicity,five health states of increasing severity were defined for the physicianrespondents. For each health state, the physicians were asked to respondto a sequence of questions to identify the lowest amount of full-qualitylife-months a typical patient would consider to be comparable to livingone year in the defined state.

The responses were then converted into utility scores by dividing thenumber of months indicated by the physicians for each health state by 12months. For example, if the physician indicated that 11 months of full-qualitylife was equivalent to one year with numbness due to mild neurotoxicity,the utility for that health state was 11/12 or 0.92.

In other words, the higher the utility score, the more the physicianfeels that the health state is an acceptable trade-off between benefit(greater survival with treatment) and risk (side effects).

Participating physicians were categorized into two subgroups based onthe Gross Domestic Product (GDP) and health care expenditure per capitaof the countries in which they were practicing (Table1).

Comparison by Country's GDP

The 22 physicians from countries in the "higher GDP" grouprepresented Germany, Denmark, Finland, the United Kingdom, Italy, Spain,Greece, and Portugal. The 11 physicians from countries in the "lowerGDP" group represented the Czech Republic, the Slovak Republic, SouthAfrica, Hungary, Argentina, and India. Physician responses were comparedfor the two toxicities both within and between the two groups.

Worse health states were consistently associated with lower utilityassessments. As utility scores decreased, the range of scores became wider,indicating less agreement among respondents.

The mean responses were calculated for the two subgroups of physiciansfrom countries with higher and lower GDPs (Table2). Within each subgroup, the responses tended to be similar, especiallyfor the mild health states (95% confidence intervals were less than ±0.05).

However, physicians from the higher GDP countries valued individualhealth states with lower utility scores (implying a less favorable viewof the particular health state) than those given by the physicians fromthe lower GDP countries.

For example, physicians from higher GDP countries viewed mild neurotoxicitywith cis-platinum therapy as having a score of 0.83 vs 0.91 given by thephysicians from lower GDP countries.

This study has important results with possible applications to clinicalpractice. First, the data provide empirical support for including healthstatus and utility assessments when considering chemotherapeutic options.Second, there were significant international variations between the twogroups. Thus, within broad cultural categories, there is likely to be somegeneral consensus on preferences for particular health states, yet culturalgroups are likely to view illness differently.

International quality of life studies are important in evaluating cancertreatments. While previous studies have focused on past and present qualityof life, few have included utility assessments, which incorporate expectationsfor quality of life in the future.

The utility assessment study discussed here shows that subjects fromcountries with higher per capita GDP have markedly different evaluationsof health states than do subjects from countries with lower GDPs. Culturaldifferences in attitudes need to be understood to make the most appropriatecare and treatment decisions for patients in different countries.

References:

1. Hunt S, Alonso J, Bucquet D, et al: Cross-cultural adaptation ofhealth measures. Health Policy 19:33-34, 1991.

2. Campos SS, Johnson TM: Cultural considerations, in Spilker B (ed):Quality of Life Assessment in Clinical Trials. New York, Raven Press Ltd,1990.

3. Kleinman A, Eisenberg L, Good B: Culture, illness, and care. AnnIntern Med 88:251-258, 1978.

4. Kaplan RM: Quality of life assessment for cost/utility studies incancer. Cancer Treat Rev 19A:85-86, 1993.

5. Kuyken W: Quality of life assessment across cultures. Int J MentHealth 23(2):5-27, 1994.

7. Patrick DL, Sittampalam Y, Somerville SM, et al: A cross-culturalcomparison of health status values. Am J Public Health 75:1402-1407, 1985.

8. Hunt S, Wiklund I: Cross-cultural variation in the weighting of healthstatements: A comparison of English and Swedish valuations. Health Policy8:227-235, 1987.

9. Hurny C et al: Quality of life measures for patients receiving adjuvanttherapy for breast cancer: An international trial. Eur J Cancer 28:118-124,1992.

10. Ali NS, Khalil HZ, Yousef W: A comparison of American and Egyptiancancer patients' attitudes and unmet needs. Cancer Nurs 16(3):199-202,1993.

11. Kodiath MF, Kodiath E: A comparative study of patients who experiencechronic malignant pain in India and the United States. Cancer Nurs 18(3):189-196,1995.

12. Weinstein JW, Bennett CL: International quality of life studiesin oncology: Literature review and case study. Journal of the Lurie CancerCenter 5(2):90-92, 1997.