Smoking dialysis patients less likely to get kidney transplant

Dialysis patients who smoke have a lower life expectancy and are less likely to get a kidney transplant, a new study from the University of Limerick shows.

The risks of dying sooner are especially high for younger patients, the researchers found.

"Smoking is a well-known risk factor for death and disability for patients in the general population," says Prof Austin Stack, senior author of the study and a consultant nephrologist at University Hospital Limerick and director of the Health Research Institute at the University of Limerick.

“Dialysis patients have extremely high premature death rates that are between 10- and 100-fold higher than in the general population, and smoking contributes substantially to lower patient survival.”

The study followed 1.22 million dialysis patients in the US over two years and was published in the scientific journal BMC Nephrology. It is one of the largest studies of its kind ever conducted, Prof Stack said.

Findings revealed that smokers were significantly more likely to die than non-smokers, and this was true for men and women of all ages. However, the effects were particularly striking for younger patients.

Furthermore, smokers “were between 26 per cent and 50 per cent less likely to receive a kidney transplant taking all other factors into consideration”, Prof Stack said.

As transplants are the best alternative for kidney failure patients, this means that smokers have less chance of receiving a potentially life-saving treatment, further endangering their future.

Aggressive action

These results have prompted the authors to recommend aggressive action against smoking in dialysis patients.

“Smoking is a major risk amplifier for all patients on dialysis,” said Prof Stack. “Consequently, we believe that kidney specialists and all healthcare providers should engage with their patients to pursue smoking cessation strategies at each and every opportunity.”

The study further analysed the contribution of other known risk factors – such as cardiovascular disease – to premature death in dialysis patients.

Researchers found that those patients with pre-existing cardiovascular conditions were more likely to die sooner. In patients who smoke, the risk was even higher.

Smoker patients with pre-existing cardiovascular disease were found to have the smallest chances of receiving a kidney transplant.

The increased risks conferred by smoking could not be attributed to any other factors such as non-cardiovascular conditions, socioeconomic and lifestyle factors.

The study was funded by the Health Research Board (HRB) and the Irish Heart Foundation (IHF).

Vanesa Martinez is on placement at The Irish Times under the BSA/SFI media fellowship programme