Psychic vulnerability and the associated risk for cancer.

Abstract

Psychic vulnerability has been associated with a number of physical symptoms and diseases. This study was designed to estimate the incidence of cancer in a random sample of persons in the general Danish population in relation to a personality characteristic measured by the Test of Psychic Vulnerability. The authors examined the cancer incidence in a cohort of 5136 randomly sampled persons age > 25 years living in Copenhagen County, Denmark. The responses to questionnaires and the results of examinations, including the Test of Psychic Vulnerability, were collected during 1982-1984 and during 1991-1992. The observed numbers of cancers were compared with the numbers that would have been expected if the cohort members had experienced the same risk of cancer as the population of Copenhagen County. Regression analyses were performed with the Cox proportional hazards model to adjust for well-known risk factors for cancer. A total of 403 cancers were observed, and 412.02 were expected, yielding a standardized incidence ratio of 0.98 (95% confidence interval [95% CI], 0.88-1.19). The authors did not observe a significant increase in the risk of site specific cancers. The risk for cancer was not influenced by the type of vulnerability in a multivariate analysis (hazards ratio, 1.16; 95% CI, 0.85-1.57). The authors found no increased risk for cancer among psychically vulnerable persons compared with nonvulnerable persons; however, the results indicate that behavior and certain life-style factors may be determined by personality, which, in turn, may determine the risk for cancer.