Affiliations of authors: N. Nakaya (Division of Epidemiology, Department of Public Health and Forensic Medicine, and Department of Behavioral Medicine), Y. Tsubono, Y. Nishino, T. Ohkubo, A. Hozawa, I. Tsuji, S. Hisamichi (Division of Epidemiology, Department of Public Health and Forensic Medicine), Tohoku University Graduate School of Medicine, Sendai, Japan; T. Hosokawa, Department of Human Development Disability, Tohoku University Graduate School of Education; D. Shibuya, Miyagi Cancer Society, Sendai; S. Fukudo, Department of Behavioral Medicine, Tohoku University Graduate School of Medicine; A. Fukao, Department of Public Health, Yamagata University School of Medicine, Yamagata, Japan.
Correspondence to: Yoshitaka Tsubono, M.D., Division of Epidemiology, Department of Public Health and Forensic Medicine, Tohoku University Graduate School of Medicine, Sendai 9808575, Japan (e-mail: ytsubono{at}metamedica.com).
![]() |
ABSTRACT |
---|
![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() |
---|
![]() |
INTRODUCTION |
---|
![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() |
---|
The findings of subsequent studies examining the association between personality and cancer incidence (1,311) or mortality (1214) have been inconsistent. Of six retrospective studies reported to date (16), four found statistically significant associations between higher scores for extraversion (2,3), lower scores for neuroticism (2,4,5), and lower scores for trait anxiety (4) and increased risk of cancer of the breast (4), lung (2,5), and all sites combined (3). The other two studies found no association between personality scales and breast (1) or gastric (6) cancer. Of 10 prospective cohort studies (714), five found statistically significant associations between "Type 1" personality [understimulation (12)] or hopelessness (8) and total cancer and between anti-emotionality (an absence of emotional behavior or a lack of trust in ones own feelings) (7) and breast cancer. The other five prospective studies found no statistically significant associations between personality and breast cancer (10) or total cancer (9,11,13,14). The majority of these studies had methodological limitations, including the use of a retrospective design (16), a small number of cancer cases [ranging from 29 (12) to 249 (5)], and failure to control sufficiently for potentially confounding variables such as smoking and alcohol use (17,10,12).
To further examine the association between personality and the risk of cancer, we conducted a population-based prospective cohort study in rural Japan. This study used the Japanese version of the personality questionnaire developed by Eysenck and colleagues (15) and involved 986 incident and 671 prevalent cancer cases, the largest number of cases to date.
![]() |
SUBJECTS AND METHODS |
---|
![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() |
---|
We have reported the design of this prospective cohort study in detail elsewhere (16,17). Briefly, we delivered two self-administered questionnaires to all 51 921 residents aged 4064 years in 14 municipalities of Miyagi Prefecture in rural northern Japan from June through August 1990. The first questionnaire asked about various health habits, and the second was the Japanese version of the Eysenck Personality Questionnaire-Revised (EPQ-R) Short Form (15). The questionnaires were delivered to, and collected at, the subjects residences by members of health promotion committees appointed by the municipal governments. The response rate for the first questionnaire was 91.7% (n = 47 605), and that for the second questionnaire among the respondents to the first was 79.8% (n = 41 442). The study protocol was approved by the institutional review board of Tohoku University Graduate School of Medicine. We considered the return of self-administered questionnaires signed by the subjects to imply their consent to participate in the study.
Exposure Data
The first questionnaire asked about demographic variables, personal and family histories of cancer and other diseases, and health habits, including smoking, alcohol use, diet, use of health services, and self-reported height and weight. The second questionnaire was a Japanese translation of the original English version of the EPQ-R Short Form, one of a series of personality inventories developed by Eysenck and colleagues (18). The EPQ-R has 48 questions with dichotomized responses (yes or no); there are 12 questions for each of four personality subscales (extraversion, neuroticism, psychoticism, and lie). Scores on each subscale range from 0 to 12, with higher scores indicating a greater tendency to possess the personality trait represented by each subscale. Extraversion represents sociability, liveliness, and surgency; neuroticism represents emotional instability and anxiousness; psychoticism represents tough-mindedness, aggressiveness, coldness, and egocentricity; and lie represents unsophisticated dissimulation and social naivety or conformity (19).
Several of Eysencks personality questionnaires have been translated to Japanese (15,20,21) and have been applied in various research and clinical settings, including studies examining associations with tobacco and nicotine dependence in male smokers (22); health perception, life satisfaction, and other measures of quality of life in rural community residents (23); behaviors for coping with stress in female college students (24); and adjustment of high school students in an international exchange program (25). These studies indicate that Eysencks personality theory is as applicable to Japanese individuals as it is to Western individuals.
In previous work (15), we developed the Japanese version of the EPQ-R and examined its reproducibility and validity among 329 college students and 253 adults. Cronbachs coefficient, a measure of internal consistency, was greater than 0.70 for all subscales except psychoticism (0.42 for college students and 0.48 for adults). Testretest reliability coefficients of the four subscales over a 6-month period ranged from 0.70 to 0.85, indicating substantial stability. Confirmatory factor analysis supported the original theoretical structure of the four scales proposed by Eysenck and colleagues (18). Scores on the four subscales were highly correlated with scores on similar subscales in the Japanese versions of the Sixteen Personality Factor Questionnaire (26) and the Maudsley Personality Inventory (20), indicating that the questionnaire had a high degree of concurrent validity.
Follow-Up
We used population registries in the 14 municipalities to ascertain the vital and residential status of the subjects from June 1, 1990, through December 31, 1997. We identified incident cases of cancer by computerized record linkage with the Miyagi Prefectural Cancer Registry, which covers the study area (27).
Of the 41 442 subjects who responded to the two questionnaires, we excluded 8618 subjects for whom responses to any of the 48 items in the EPQ-R were missing and 54 subjects who responded "yes" or "no" to every one of the 48 items. We also excluded 2493 subjects who indicated that the two questionnaires had been completed with the aid of other family members because we considered that such aid might have affected the response patterns of the study subjects. For the analysis of incident cancer, we also excluded 671 subjects with prevalent cancer ascertained either by self-reporting in the health-habit questionnaire or from cancer registry records. Consequently, 29 606 subjects (14 473 men and 15 133 women) remained for the analysis of incident cancer. Over the follow-up period, 986 incident cases of cancer (588 in men and 398 in women) were identified.
We observed little difference between subjects who completed the two questionnaires (n = 41 442) and those who remained for the analysis of incident cancer (n = 29 606). Specifically, for men in the two groups, the mean ages were 51.7 and 51.1 years, the prevalence of current smokers was 61.1% and 60.8%, respectively, and the prevalence of family history of cancer was 25.8% in both groups. Characteristics of women in the two groups were also similar. Furthermore, the subjects who remained for the current analysis made up 57% of the total population of adults aged 4064 years at baseline (June 1, 1990) in the study area. The two groups were also similar with respect to the distribution of sex (men made up 48.9% and 48.7% of the groups, respectively) and age classes (e.g., subjects aged 5059 years made up 36.9% and 38.7% of the groups, respectively). Taken together, these findings indicate that the subjects we analyzed were representative of the total population in the study area.
Statistical Analysis
We counted person-years of follow-up for each subject from June 1, 1990, until the date of diagnosis of cancer, date of emigration outside the study districts (because of logistical limitations), date of death, or the end of the study period (December 31, 1997), whichever occurred first. A total of 215 810 person-years resulted. A total of 1088 subjects (3.7% of the analytic cohort) were lost to follow-up during the study period.
Each personality subscale was divided into four categories to divide the total subjects as closely as possible into even-sized quartiles. Relative risk (RR) was computed as the incidence among subjects in each category of a personality subscale divided by the incidence among subjects in the lowest category. We used Cox proportional hazards regression to adjust for sex, age, and other potentially confounding variables (28) using the SAS PHREG procedure in the SAS version 8.2 statistical software package (SAS Institute, Cary, NC). The assumption of proportional hazards was verified graphically. We repeated all analyses after excluding the 320 cancer cases diagnosed after baseline in the first 3 years of follow-up (194 men and 126 women) in case health issues related to as-yet-undiagnosed cancer affected personality. P values for testing statistical significance of linear trends were calculated by treating personality subscales as continuous variables. All P values were two-tailed. This study has approximately 85% statistical power, with a two-sided error level of 5%, to detect a true hazard ratio of 1.3 for total cancer among the highest versus lowest categories of the personality subscales (29).
In addition to sex and age, we considered the following variables as potential confounders a priori: cigarette smoking (never smoked, smoked in the past, currently smoking 119 cigarettes per day, or currently smoking 20 cigarettes per day), alcohol consumption (never drank alcohol, drank in the past, currently drinking 22.7 g of alcohol or less per day, or currently drinking 22.8 g of alcohol [corresponding to one small bottle of sake] or more per day), body mass index in kg/m2 (
18.4, 18.5 to 24.9, or
25.0); education (in school until age 15 years or younger, age 1618 years, or age 19 years or older), and family history of cancer (presence or absence in first-degree relatives). For the adjustment of smoking, we entered three types of smoking variables into separate multivariable models, including 1) categorical variables for smoking status, as mentioned above; 2) the number of pack-years of smoking as a continuous variable; or 3) the number of the cigarettes currently smoked per day as a continuous variable. Because we observed similar results irrespective of the choice of these variables, we presented the results with the categorical variables for smoking status.
For the cancer risk estimates, we analyzed both total incident cancer (986 cases) and the four most common cancer sites among the subjects: stomach (229 cases), colorectum (186 cases), lung (108 cases), and breast (87 cases, all women). We also used combined cancer endpoints according to whether they were associated with smoking; for smoking-associated cancers, we included cancers of the lung (108 cases), esophagus (34 cases), pancreas (32 cases), cervix (25 cases), bladder (21 cases), oral cavity (21 cases), and pharynx (16 cases) (30), for a total of 257 cases. We excluded from the analysis of smoking-associated cancers 12 cancer cases whose primary sites were not specified, thus leaving 717 cases designated as not smoking-associated.
We also conducted additional analyses to examine how study design (retrospective or prospective) and duration of follow-up (in prospective analyses) affected the associations between personality scales and the risk of total cancer. In the retrospective analysis, we used as an endpoint the 671 cases of cancer that were prevalent at baseline and had been ascertained from self-reports in the health-habit questionnaire or from cancer registry records. We estimated odds ratios of the presence of prevalent cancers for different levels of personality subscales by unconditional logistic regression (28). In the prospective analyses, we used two durations of follow-up: the first analysis involved the first 3 years of follow-up from the baseline, and the second involved 7 years of follow-up but excluded cancer cases diagnosed within the first 3 years.
![]() |
RESULTS |
---|
![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() |
---|
|
|
We also found no statistically significant associations between any of the personality subscales and the risk of the four cancers that were most common among the subjects (stomach, colorectum, lung, and breast) and cancer at sites defined according to whether or not they are associated with smoking (Table 3). Across all levels of extraversion, from lowest to highest, there was some evidence of a decreased risk of breast cancer (Ptrend = .046), but the association disappeared when the 32 cases of breast cancer diagnosed in the first 3 years of follow-up were excluded.
|
|
![]() |
DISCUSSION |
---|
![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() |
---|
Our findings in the analyses according to study design and the duration of follow-up (Fig. 1) may provide clues for interpreting the discrepancies among previous studies on personality and cancer. That is, we found a statistically significant positive association between neuroticism and prevalent cases of cancer at baseline and with cancer cases diagnosed in the first 3 years of follow-up. A neurotic tendency among subjects with prevalent cases of cancer may be a consequence, rather than a cause, of having been diagnosed with cancer. Similarly, a neurotic tendency of subjects with cancer diagnosed in the early years of follow-up may be a consequence of subclinical symptoms caused by cancers that were present but undiagnosed at baseline. In contrast, we found no association between neuroticism and the risk of being diagnosed with cancer during the later years of follow-up. The majority of these cancer cases would have been asymptomatic at baseline, when personality was assessed. This analysis would be least susceptible to distortion when examining the temporal association between personality (putative cause) and the development of cancer (effect).
Although the questionnaire that we used, EPQR, measures general personality dimensions rather than personality dimensions more specifically hypothesized to be associated with cancer, previous studies finding statistically significant associations with cancer risk also use questionnaires developed by Eysenck (25) and another questionnaire developed for general use (7). It is therefore unlikely that the observed lack of association is due mainly to the use of the general personality questionnaire.
Several investigators have developed measures of personality dimensions that are more specifically hypothesized to be associated with cancer and have examined the associations between these measures and cancer risk. The first line of work was initiated by Temoshok et al. (31), who observed that tumor thickness in patients with malignant melanoma was positively associated with "Type C" personality, which they described as cooperative, unassertive, patient, suppressive of negative emotions, and accepting/compliant with external authorities. Subsequent studies have focused mainly on the association between components or related factors of "Type C" personality (such as emotional suppression and helplessness/hopelessness) and cancer recurrence or survival rather than incidence, but there is little consistent evidence that these factors play an important role in cancer survival or recurrence (32). Other studies have examined the association between cancer incidence and anti-emotionality (7,33), repression (10), and hopelessness (8). Although some studies (7,8,33) observed statistically significant positive associations, they had methodologic limitations, including a small number of cancer cases [ranging from 73 (8) to 166 (33)] and poor control for potentially confounding variables (33).
The second line of work was conducted by Grossarth-Maticek and colleagues (12). They classified personality into four subtypes: "Type 1" (understimulation), "Type 2" (overarousal), "Type 3" (ambivalence), and "Type 4" (personal autonomy) and examined the association between the personality type and disease in three prospective studies among a population in Yugoslavia, a population in Heidelberg, and a stressed group in Heidelberg. They found "Type 1" personalities to be prone to cancer, "Type 2" to be prone to coronary heart disease, and "Type 3" and "Type 4" to be healthy (12). They observed that the proportion of subjects who died from cancer during the follow-up was markedly higher in "Type 1" individuals than in "Type 4" individuals (e.g., 46.2% versus 0.6% in the Yugoslav study). However, various criticisms have been raised about these studies, including vague descriptions of inclusion and exclusion criteria for the study subjects (9,34,35), insufficient information on establishment and confirmation of cancer diagnosis (9,3537), and no information on validity of personality measurement (9,34,37,38).
In this study, we examined in detail potential confounding and effect modification by smoking and other covariates on the associations between personality scales and cancer risk. Various studies have reported that smoking is associated with extraversion or other personality characteristics (39,40), and some investigators have considered these findings as evidence that the association between smoking and lung cancer is confounded by personality variables (41). We found that current smokers tended to score high on extraversion, low on neuroticism, high on psychoticism, and low on the lie scale compared with never smokers (Table 1). We also observed that other risk factors for cancer, such as alcohol consumption and being overweight, were associated with these personality variables. Nevertheless, we observed little difference in the point estimates of RRs whether or not multivariable adjustments were made for smoking and other variables (Table 2
). We also observed no material variations in the results of analyses stratified by these covariates. These findings indicate that the observed lack of association between personality factors and incident risk of total cancer in our study was not substantially confounded or modified by smoking, using alcohol, or being overweight.
Although this study focused on the association between personality and cancer incidence, we have observed an association between high alcohol consumption and all-cause mortality among men in this cohort (17). We have also observed in this cohort positive associations between smoking and lung cancer, between alcohol consumption and several cancers, and between family history of cancer and risk of total cancers (Tsubono Y: unpublished observations). Therefore, our subjects should be considered a typical series of persons with regard to the associations between risk factors other than personality and cancer incidence or general health.
To our knowledge, this is the largest prospective cohort study of personality and cancer to date, involving 986 incident cases of cancer at all sites combined. However, the number of cases of individual cancer sites was still only modest at best, even for the most common cancer sites observed among our subjects. Therefore, our study may not have had sufficient statistical power for detecting small increases or decreases in the risk of cancer at individual sites associated with personality scales. This is particularly the case for hormone-related cancers, such as breast, endometrial, and prostate cancers, for which the incidence rates are lower in Japan than in Western countries (27). Nevertheless, our findings support the hypothesis that personality does not play a substantial role in the causation of cancer in general.
![]() |
NOTES |
---|
![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() |
---|
![]() |
REFERENCES |
---|
![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() |
---|
1 Greer S, Morris T. Psychological attributes of women who develop breast cancer: a controlled study. J Psychosom Res 1975;19:14753.[CrossRef][ISI][Medline]
2 Kissen DM, Eysenck HJ. Personality in male lung cancer patients. J Psychosom Res 1962;6:1237.[CrossRef][ISI][Medline]
3 Coppen A, Metcalfe M. Cancer and extraversion. BMJ 1963;2:189.
4 Morris T, Greer S, Pettingale KW, Watson M. Patterns of expressing anger and their psychological correlates in women with breast cancer. J Psychosom Res 1981;25:1117.[CrossRef][ISI][Medline]
5 Kissen DM, Brown RI, Kissen M. A further report on personality and psychosocial factors in lung cancer. Ann N Y Acad Sci 1969;164:53545.[ISI][Medline]
6 Yamaoka K. Shigehisa T, Ogoshi K, Haruyama K, Watanabe M, Hayashi F, et al. Health-related quality of life varies with personality types: a comparison among cancer patients, non-cancer patients and healthy individuals in a Japanese population. Qual Life Res 1998;7:53544.[CrossRef][ISI][Medline]
7 Bleiker EM, van der Ploeg HM, Hendriks JH, Ader HJ. Personality factors and breast cancer development: a prospective longitudinal study. J Natl Cancer Inst 1996;88:147882.
8 Everson SA, Goldberg DE, Kaplan GA, Cohen RD, Pukkala E, Tuomilehto J, et al. Hopelessness and risk of mortality and incidence of myocardial infarction and cancer. Psychosom Med 1996;58:11321.[Abstract]
9 Shapiro IR, Ross-Petersen L, Saelan H, Garde K, Olsen JH, Johansen C. Extraversion and neuroticism and the associated risk of cancer: A Danish cohort study. Am J Epidemiol 2001;153:75763.
10 Hahn RC, Petitti DB. Minnesota Multiphasic Personality Inventory-rated depression and the incidence of breast cancer. Cancer 1988;61:8458.[ISI][Medline]
11 Persky VW, Kimpthorne-Rawson J, Shekelle RB. Personality and risk of cancer: 20-year follow-up of the Western Electric Study. Psychosom Med 1987;49:43549.[Abstract]
12 Grossarth-Maticek R, Eysenck HJ, Vetter H. Personality type, smoking habit and their interaction as predictors of cancer and coronary heart disease. Pers Individ Dif 1988;9:47995.[CrossRef][ISI]
13 Shekelle RB, Raynor WJ, Ostfeld AM, Garron DC, Bieliauskas LA, Liu SC, et al. Psychological depression and 17-year risk of death from cancer. Psychosom Med 1981;43:11725.[Abstract]
14 Almada SJ, Zonderman AB, Shekelle RB, Dyer AR, Daviglus ML, Costa PT Jr, et al. Neuroticism and cynicism and risk of death in middle-aged men: the Western Electric Study. Psychosom Med 1991;53:16575.[Abstract]
15 Hosokawa T, Ohyama M. Reliability and validity of the Japanese version of the short form Eysenck Personality Questionnaire-Revised. Psychol Rep 1993;72:82332.[ISI]
16 Fukao A, Tsubono Y, Komatsu S, Tsuji I, Minami Y, Hisamichi S, et al. Cohort study on the relation of lifestyle, personality and biologic markers to cancer in Miyagi, Japan: study design, response rate and profiles of the cohort subjects. J Epidemiol 1995;5:1537.
17 Tsubono Y, Yamada S, Nishino Y, Tsuji I, Hisamichi S. Choice of comparison group in assessing the health effects of moderate alcohol consumption. JAMA 2001;286:11778.
18 Eysenck HJ, Eysenck SB. Manual of the Eysenck Personality Questionnaire (adult and junior). London (UK): Hodder & Stoughton; 1975.
19 Eysenck HJ, Eysenck SB. Manual of the Eysenck Personality Scales. (EPS Adult). London (UK): Hodder & Stoughton; 1991.
20 MPI Kenkyukai. Shin Seikaku Kensahou [Manual of the Maudsley Personality Inventory, Japanese version]. Tokyo (Japan): Seishin Shobo; 1969.
21 Shigehisa T, Ikeda S, Koike S. Rationality-antiemotionality, harmony-seeking and related variables: an analysis of premorbid personality. J Tokyo Kasei Gakuin Univ 1995;35:42136.
22 Kawakami N, Takai A, Takatsuka N, Shimizu H. Eysencks personality and tobacco/nicotine dependence in male ever-smokers in Japan. Addict Behav 2000;25:58591.[CrossRef][ISI][Medline]
23 Kitamura T, Kawakami N, Sakamoto S, Tanigawa T, Ono Y, Fujihara S. Quality of life and its correlates in a community population in a Japanese rural area. Psychiatry Clin Neurosci 2002;56:43141.[CrossRef][ISI][Medline]
24 Nakano K. Role of personality characteristics in coping behaviors. Psychol Rep 1992;71:68790.[ISI][Medline]
25 Furukawa T, Shibayama T. Factors influencing adjustment of high school students in an international exchange program. J Nerv Ment Dis 1994;182:70914.[ISI][Medline]
26 Izawa S, Yamaguchi K, Tatsuoka M, Motigi M, Uchiyama T, Ueno K. Manual of the Sixteen Personality Factor Questionnaire (Japanese version). Tokyo (Japan): Nihon Bunka Kagakusha; 1982.
27 Takano A, Okuno Y. Japan, Miyagi Prefecture. In: Parkin DM, Whelan SL, Ferlay J, Raymond L, Young J, editors. Cancer incidence in five continents. Vol. 7. IARC Sci Publ 1997;(143):3869.
28 Rothman KJ, Greenland S. Modern epidemiology. 2nd ed. Philadelphia (PA): Lippincott-Raven; 1998. p. 35999.
29 Schoenfeld DA, Richter JR. Nomograms for calculating the number of patients needed for a clinical trial with survival as an endpoint. Biometrics 1982;38:16370.[ISI][Medline]
30 World Cancer Research Fund in association with American Institute for Cancer Research. Food, nutrition and the prevention of cancer: a global perspective. Washington (DC): 1997. p. 5067.
31 Temoshok L, Heller B, Sagebiel RW, Blois MS, Sweet DM, DiClemente RJ, et al. The relationship of psychosocial factors to prognostic indicators in cutaneous malignant melanoma. J Psychosom Res 1985;29:13953.[CrossRef][ISI][Medline]
32 Petticrew M, Bell R, Hunter D. Influence of psychological coping on survival and recurrence in people with cancer: systematic review. BMJ 2002;325:1066.
33 Grossarth-Maticek R, Bastiaans J, Kanazir DT. Psychosocial factors as strong predictors of mortality from cancer, ischaemic heart disease and stroke: the Yugoslav prospective study. J Psychosom Res 1985;29:16776.[CrossRef][ISI][Medline]
34 Pelosi AJ, Appleby L. Psychological influences on cancer and ischaemic heart disease. BMJ 1992;304:12958.[ISI][Medline]
35 Amelang M. Tales from Crvenka and Heidelberg: what about the empirical basis? Psychol Inq 1991;2:2336.
36 Derogatis LR. Personality, stress, disease, and bias in epidemiologic research. Psychol Inq 1991;2:23842.
37 Suinn RM. Prediction of cancer from psychological measures. Psychol Inq 1991;2:26876.
38 Kiecolt-Glaser JK, Chee M. Personality, stress, and cancer: a re-examination. Psychol Inq 1991;2:24951.
39 McManus IC, Weeks SJ. Smoking, personality and reasons for smoking. Psychol Med 1982;12:34956.[ISI][Medline]
40 Vollrath M, Torgersen S. Who takes health risks? A probe into eight personality types. Pers Individ Dif 2002;32:118597.[CrossRef][ISI]
41 Eysenck HJ. Smoking, personality and psychosomatic disorders. J Psychosom Res 1963;7:10730.[CrossRef][ISI]
Manuscript received August 13, 2002; revised March 20, 2003; accepted March 28, 2003.
This article has been cited by other articles in HighWire Press-hosted journals:
Correspondence about this Article
![]() |
||||
|
Oxford University Press Privacy Policy and Legal Statement |