Chen-Hsun Ho, MD, and colleagues at the National Taiwan University in Taipei studied 1,306 men who sex hormones were measuring during a medical examination. The investigators defined prediabetes as impaired fasting glucose (IFG), impaired postprandial glucose (IPG), or glycated hemoglobin (HbA1c) levels of 5.7%-6.4%.
Of the 1,306 men, 577 (44.2%) had normoglycemia, 543 (41.6%) had prediabetes, and 186 (14.2%) had diabetes. Compared with normoglycemic men, those with prediabetes had a nearly 1.9 times increased risk of testosterone deficiency (levels less than 300 ng/dL), the investigators reported in PLOS One. Men with diabetes had an approximately 2.4 times increased risk of testosterone deficiency.
After adjusting for age and the presence of metabolic syndrome, prediabetic and diabetic men had similar increased risks of testosterone deficiency (49% and 50%, respectively) compared with normoglycemic men. “The substantially increased risk suggests that testosterone should be measured routinely in men with prediabetes,” the investigators concluded.
In addition, IFG, IPG, and HbA1c were significantly associated with an increased risk of testosterone deficiency after adjusting for age. After adjusting for age and metabolic syndrome, HbA1c 5.7%-6.4% was associated with a 46% increased likelihood of testosterone deficiency compared with an HbA1c less than 5.7%.