Missed cancer screenings linked to earlier death from non-cancer causes

Adults who skip recommended cancer screenings may be more likely than those who do not skip them to die prematurely from causes unrelated to malignancies, a US study suggests. 

Researchers think skipping screenings may be a marker for more generally neglecting one’s own health. 

“It was not a direct effect of missing the cancer screening that led to the increased mortality in the non-compliers,” said study co-author Paul Pinsky of the National Cancer Institute in Bethesda, Maryland. 

“Rather, we believe that non-compliance with the screening was a marker of a wider health behavioural profile of general non-compliance with or non-adherence to medical tests and treatments,” Pinsky said by e-mail. “Non-compliance with medical procedures has also been linked, in this and other studies, to other unhealthy lifestyle factors such as obesity and smoking, and to lower education.” 

The researchers examined data on 64,567 adults (age 62, on average) who were told to get screened for lung and colorectal cancers. Men were also advised to get tested for prostate tumours and women were asked to get checked for ovarian cancer. 

Overall, 55,065 participants, or about 85 per cent, did what they were told and 6,954, or about 11 per cent, did not. 

Within 10 years, people who did not get any of their recommended cancer screenings were 73 per cent more likely to die of causes other than the tumours targeted by the tests than participants who got all of their screenings, the study found. 

Some screening was better than none at all, the researchers also found. 

About 2,500 participants, or 4 per cent, were partially compliant with screening recommendations, getting some but not all of what was recommended based on their sex and age. These individuals were 36 per cent more likely to die of causes other than cancer during the study than their counterparts who received all recommended screenings. 

Even after researchers accounted for other factors that can hasten death like smoking, obesity and multiple chronic medical issues, compliance with cancer screenings still mattered: people who did not get any screenings were 46 per cent more likely to die of other causes during the study and people who skipped some screenings were 26 per cent more likely to die. 

One limitation of the study is that researchers were missing more data for people who skipped screenings than for people who got recommended cancer tests, the authors note in JAMA Internal Medicine. 

Because all of the people in the study knew they would be asked to get multiple screenings, it is also possible that their results do not reflect what might happen in the broader population. 

Even so, the results suggest that the same factors that motivate screening decisions might also impact other aspects of health, said Deborah Grady of the University of California, San Francisco, who co-wrote an accompanying editorial. 

“There is no way that getting screened for cancer can reduce the risk of dying of causes totally unrelated to screening,” Grady said by e-mail. 

“What probably accounts for this association is the fact that people who follow advice to undergo screening have a lot of other health-related behaviours,” Grady added. “It’s likely that it’s these sorts of behaviours that reduce the risk of dying.”