The findings, appearing in the December 22 issue of the Journal of the American Medical Association, run counter to the widely held belief that some people are able to "cheat death" through sheer willpower or perhaps by some other, unknown psychosomatic mechanism.
DonnYoung, a biostatistician and research scientist in the OSU Comprehensive Cancer Center, along with Erinn Hade, a senior consulting research statistician in the OSU Center for Biostatistics, examined all death certificates in the Ohio Department of Health for the twelve-year period between 1989 and 2000, a total of over 1.2 million records. They selected for specific study only those records listing cancer as the leading cause of death. The process generated a database of 309,221 cancer deaths that were further identified by date of birth, gender, race and ethnicity.
An initial analysis of all deaths -- those due to cancer and non-cancerous causes – revealed the lowest mortality rate occurring during the summer months, then escalating until it reached its highest level in the three weeks after Christmas. Young says this is a well-known and predictable seasonal pattern generally attributed to changing temperatures. "We've known for a long time that higher death rates are directly associated with falling temperatures."
Cancer mortality, however, showed no variation from season to season.
Conducting a second analysis of only the deaths from cancer, Young looked for what statisticians call a "dip/peak" phenomenon – a decline in the death rate the week before an event with a corresponding increase in the week afterwards, an indication that something may be causing a variation in normal patterns.
He chose cancer patients over those with other types of diseases and disorders because cancer patients typically have an extended and more predictable pathway to death, compared to those who suffer from heart disease, stroke or diabetes, for example.
"We chose to look at three potentially meaningful events: Christmas, because it's the major religious holiday in the United States; Thanksgiving, because it is the most widely celebrated secular holiday, and also the person's birthday, believing it would hold significance for many people," says Young.
In examining the records, he found no significant difference overall in the proportion of cancer patients dying before the events compared with the number dying afterward.
There was an increase in cancer deaths among blacks during the week prior to Thanksgiving, however, and an increase in cancer deaths among white women in the week prior to their birthday. While statistically significant, Young doubts the findings are meaningful.
"We believe they are statistical artifacts – phenomena that appear when you start data-dredging, testing hypothesis after hypothesis," he says.
The study refutes conclusions drawn from earlier studies showing striking changes in death patterns among particular populations. For example, in separate studies over a decade ago of Jewish men and elderly Chinese women in California, death rates appeared to drop significantly right before important religious and cultural celebrations – and then increased dramatically immediately afterwards.
But Young points out those studies covered relatively small populations, and may reflect a general tendency for people to selectively remember positive events. He says while some may feel the findings of the study take away the hope of a prolonged life, others may see them in a different light.
"I think all of us may know or have heard of someone 'hanging on' through the holidays or trying to live until an important occasion. But the figures just don't bear this out as something that people can really do. I think the most important thing for all of us to take away from this is the notion of attending to what is important – in other words, don't put off what is meaningful in life. Do it now, before it is too late."
The OSU Cancer Center Support Grant supported the research.
Contact: Michelle Gailiun, Medical Center Communications, 614-293-3737, or Gailiun.1@osu.edu
Journal
JAMA