Researchers who studied a group of healthy middle-aged Japanese men found that those with lower testosterone levels had a higher risk for metabolic syndrome (MS), according to findings published online ahead of print in Urology.
Akira Tsujimura, MD, of Okaka University Graduate School of Medicine in Osaka, and colleagues measured total testosterone (TT) levels and assessed metabolic factors in 1,150 men aged 30 years or older (mean age 44 years). Compared with men in the highest quintile of TT (greater than 6.7 ng/mL), those in the first, second, third, and fourth quintiles (less than 4.0, 4.0-4.8, 4.9-5.6, and 5.7-6.7 ng/mL, respectively) had a 15.1, 8.8, 5.8, and 5.0 times increased risk of MS, respectively.
In age-adjusted analyses, each standard deviation decrement in TT was associated with a 2.3 times increased risk of MS. In addition, each standard deviation decrement in TT was associated with a 1.8 times increased risk of having abdominal obesity (a waist circumference of 85 cm or more) as well as a 1.6 times, 1.5 times, and 1.7 times increased risk of dyslipidemia, hypertension, and hyperglycemia, respectively.
The researchers defined MS as a waist circumference of 85 cm or more plus any two of the following: dyslipidemia (triglyceride level of 150 mg/dl or higher or HDL cholesterol level below 40 mg/dL, or use of antidyslipidemia medication); hypertension (systolic blood pressure of 130 mm Hg or higher or diastolic blood pressure of 85 mm Hg or higher, or use of antihypertensive medication); or hyperglycemia (fasting plasma glucose level of 110 mg/dL or higher or use of hypoglycemia medication).
“Of value in the present study was the finding that a decrease in serum TT level was directly associated with MS and metabolic factors even in generally healthy patients,” the authors wrote. “In general, metabolic components likely correlate with each other, that is, patients who are obese are also likely to have dyslipidemia, hypertension, or hyperglycemia, or a combination of these.”