Background: The metabolic syndrome has been suggested as a unifying link between a "western" lifestyle and an increased prostate cancer risk.
Methods: We assessed the associations of components of the metabolic syndrome with prostate cancer in a prospective cohort based on 29,364 Norwegian men followed up for prostate cancer incidence and mortality from 1995-1997 to the end of 2005 in the second Nord Trøndelag Health Study (HUNT 2).
Results: During a mean 9.3 years follow-up, 687 incident prostate cancers were diagnosed, and 110 men died from prostate cancer. There was little evidence that baseline BMI, waist circumference, waist-hip ratio, total or HDL-cholesterol, triglycerides, presence of the metabolic syndrome, diabetes, antihypertensive use, or cardiovascular disease were associated with incident or fatal prostate cancer. There was weak evidence that raised blood pressure was associated with an increased risk: for each SD (12 mm) increase in diastolic blood pressure, there was an 8% (95% CI = 1-17%; p = 0.04) increased risk of incident prostate cancer.
Conclusions: We found little evidence to support the hypothesis that the metabolic syndrome or its components explains higher prostate cancer mortality rates in countries with a "western" diet and lifestyle. The positive association of blood pressure with prostate cancer warrants further investigation.