Wednesday September 25 2013
Men received more benefit than women from being married
"How being married can help you survive cancer," the Daily Mail reports.
The story comes from a study which looked at whether marital status had any impact on the following cancer outcomes:
- the stage that cancer patients were diagnosed with the disease – located in a single part of the body or spread elsewhere (metastatic)
- was the cancer treated with the most appropriate treatment
- survival rates
The large US study – involving over a million people – found that married people tended to do better in all three outcomes. A particularly interesting finding was that, for some cancers, the survival benefit associated with being married was greater than for chemotherapy.
Possible reasons given for these improvements include that, particularly in men, having an attentive partner is more likely to persuade a partner to seek an early diagnosis.
Also, the support of a loved one through the illness can make a difference to the outcome. As they also point out, if this is so, it has implications for unmarried people with cancer who may benefit from greater psychosocial support.
However, this study had several limitations, including the possibility that factors other than marital status influenced the results. For example, in the US, it is possible that married people overall have greater financial resources and in turn, access to better treatments.
Where did the story come from?
The study was carried out by researchers from Harvard Oncology Program; Beth Israel Deaconess Medical Center; Dana-Farber/Brigham and Women’s Cancer Center Harvard Medical School; University of Connecticut; The University of Texas; University of California at Los Angeles, Los Angeles, CA. It was funded by the Heritage Medical Research Institute, the Prostate Cancer Foundation and others.
The study was published in the peer-reviewed Journal of Clinical Oncology.
The Daily Mail’s coverage of the study was accurate, but did not discuss any of the study’s limitations – which the researchers made clear in their conclusion.
What kind of research was this?
This was a retrospective analysis which used a large US database of cancer patients to examine the impact of marital status on the following outcomes:
- stage at diagnosis – was the cancer localised or widespread (metastatic)
- was the treatment appropriate – was it in line with previously agreed clinical guidelines for that specific cancer
- mortality rates
The analysis was limited to the 10 most common types of cancer resulting in deaths in the US (similar to the UK), such as lung cancer, breast cancer, colorectal cancer and prostate cancer.
A complete list of all cancer topics covered by NHS Choices can be found in the Health A-Z overview on cancer.
The authors point out that the results of previous research on the subject have been mixed. But if marriage confers an advantage in terms of cancer outcomes, then unmarried patients may also benefit from improved psychosocial support.
What did the research involve?
The researchers used a large national database (called the Surveillance, Epidemiology and End Results Program, or SEER) to identify 1,260,898 patients diagnosed with the 10 most common cancers, between 2004 and 2008.
Patients were excluded if their age at diagnosis was less than 18 years, if a diagnosis of cancer was only made at autopsy, if a prior malignancy had been diagnosed, if clinical information was incomplete, or if the cause of death was unknown. This left 734,889 patients in the final cohort.
- the authors first analysed the association between the patients marital status and the cancer stage at diagnosis (whether it had metastasised)
- the second stage of the analysis involved excluding patients with metastatic cancer and those for whom stage and therapy used was unknown
- they were then left with 562,758 patients. In this group they analysed the association between marital status and use of appropriate therapy – this was defined as surgery and/or radiotherapy for prostate, lung, pancreatic, liver/intrahepatic bile duct, oesophageal, and head/neck cancer, and surgery alone for breast, colorectal, and ovarian cancer (among patients with breast cancer, only women were included in the analysis as male breast cancer is extremely rare so any data taken from this group would not be representative of breast cancer patients)
- they analysed the association between marital status and dying from the specific cancer
They adjusted all findings for other factors which might affect the results (confounders) such as race, education, income and for the last two outcomes, stage of the cancer.
Marital status was classified as either married or unmarried, then reanalysed as married versus single, separated, divorced or widowed.
Researchers also compared survival rates of married cancer patients with survival benefits of chemotherapy, as found by published scientific trials.
What were the basic results?
The researchers found that married cancer patients were:
- less likely than unmarried patients to be diagnosed with metastatic disease (adjusted odds ratio [OR], 0.83; 95% confidence interval [CI], 0.82 to 0.84)
- more likely than unmarried patients to receive appropriate treatment (adjusted OR, 1.53; 95% CI, 1.51 to 1.56)
- less likely than unmarried patients to die as a result of their cancer after adjusting for demographics, stage, and treatment (adjusted hazard ratio, 0.80; 95% CI, 0.79 to 0.81)
These associations remained significant when each individual cancer was analysed.
The benefit associated with marriage was greater in men than women for all outcome measures.
For prostate, breast, colorectal, esophageal, and head/neck cancers, the survival benefit associated with marriage was larger than the published survival benefit of chemotherapy.
How did the researchers interpret the results?
The researchers point out that their results suggest that unmarried patients are at significantly higher risk of late diagnosis, undertreatment, and death resulting from their cancer. The study highlights the potentially significant impact that social support can have on cancer detection, treatment, and survival, they argue.
In an accompanying press release, the study’s lead author, Paul Nguyen, MD, a radiation oncologist at Dana-Farber and Brigham and Women's, said: “We don't just see our study as an affirmation of marriage, but rather it should send a message to anyone who has a friend or a loved one with cancer: by being there for that person and helping them navigate their appointments and make it through all their treatments, you can make a real difference to that person's outcome".
The findings of this study suggest that the close support often provided by marriage may make a difference to the stage at which cancer is diagnosed, whether it is treated appropriately and whether the patient survives the disease.
However, as the authors point out it had several limitations:
- it did not take account of unmarried, cohabiting partners. This group would have been classified as unmarried, yet they might be expected to show similar benefits in cancer outcomes to those who are married – however as the researchers pointed out, as the study mainly involved older American citizens, demographic factors would suggest that the majority of these people who were cohabiting would also be married
- the results may not apply to less common cancers not evaluated in this study
- the study had no data related to actual ‘real world’ chemotherapy outcomes – it relied on previously published research which may not be applicable to actual individual cases
- for some patients – for example, those with early prostate cancer – it may have actually been better in terms of the patient’s interests to withhold appropriate treatment – many men will live the rest of their lives without being severely affected by the cancer
- it did not take account of data on smoking and alcohol use, both of which may influence cancer survival
- it is possible that in the US, married couples have greater access than single people to cancer treatments, due to the lack of public healthcare that is freely available to all citizens
Overall, it is also possible that some as yet unmeasured factor may explain the association between marriage and better outcomes. Although as the authors point out, widowed patients also displayed poorer outcomes than those who were married, suggesting that lack of social support rather than some unmeasured confounder, is the true driver of these results.
In conclusion, the findings are of interest but should be viewed with caution.
A final point to raise, as mentioned in the press release, is that if there is a benefit, it is unlikely to be due to having a wedding ring on your finger, but rather to having access to a network of social support.
Charities such as Cancerhelp and Macmillan Cancer Support can provide both additional social, practical and emotional support.
Read more about Cancer and social care
Analysis by Bazian. Edited by NHS Choices. Follow Behind the Headlines on Twitter.