Diabetes and prediabetes increase cancer mortality
MedWire News: Individuals with diabetes or prediabetes have a significantly increased risk for death from cancer compared with nondiabetics, say researchers.
Previous studies have shown that the presence of and some treatments for diabetes increase the risk for cancer, as reported by MedWire News, but evidence for a link between diabetes and increased cancer mortality is less certain.
Qing Qiao (National Institute for Health and Welfare, Helsinki, Finland) and team investigated cancer mortality in relation to glucose tolerance status, measured using a 2-hour oral glucose tolerance test (OGTT) in 26,460 men and 18,195 women aged 25–90 years enrolled in the DECODE (Diabetes Epidemiology: Collaborative analysis of Diagnostic criteria in Europe) study.
The 17 pooled cohorts that comprised the study population were recruited between 1966 and 2004 and were followed up for between 5.9 and 36.8 years (median 15.8 years).
Diabetes was defined as a 2-hour plasma glucose level of 11.1 mmol/l or more, while prediabetes was defined as having an elevated 2-hour plasma glucose level of 7.8 mmol/l or more plus normal fasting plasma glucose (FPG; less than 7.0 mmol/l) - impaired glucose tolerance - and/or 2 hour plasma glucose concentration below 7.8 mmol/l and FPG above 7.0 mmol/l - impaired fasting glucose. Normoglycemia was defined as a 2-hour plasma glucose level below 7.8 mmol/l and normal FPG.
In total, 3235 participants died from cancer over the follow-up period. Compared with people with normoglycemia, relative risks for cancer mortality were increased by 13%, 27%, and 71% in men with prediabetes, previously undiagnosed diabetes (no prior diagnosis, but 2 hour plasma glucose levels of 11.1 mmol/l or above), and known diabetes, respectively. In women, the corresponding increases were 11%, 31%, and 43%.
In people without known diabetes, one standard deviation increase in 2-hour plasma glucose concentration increased the risk for cancer mortality by 7%.
The researchers note that men with prediabetes and diabetes were more likely to die from stomach, colorectal, or liver cancer than other cancers. In addition, women with diabetes were more likely to die from cancer of the liver or pancreas than other forms of the disease.
“The present study confirmed that diabetes and prediabetes are independent risk predictors for all cancer death, particularly death from liver cancer,” conclude the authors.
The results of this research are published in the journal Diabetologia.
MedWire (www.medwire-news.md) is an independent clinical news service provided by Current Medicine Group, a trading division of Springer Healthcare Limited. © Springer Healthcare Ltd; 2010
By Helen Albert