Abstract
ObjectiveTo assess the effect of parental age at childbirth on insulin sensitivity and other metabolic outcomes in overweight middle-aged males.
MethodsWe studied 73 men aged 46.05.4 years, who were overweight (body mass index, BMI 25-30 kg/m(2)) but otherwise healthy. Insulin sensitivity was assessed by the Matsuda method from an oral glucose tolerance test. Other assessments included dual-energy X-ray absorptiometry-derived body composition, lipid profile, 24-hour ambulatory blood pressure, and carotid intima-media thickness. Maternal and paternal ages were highly correlated (r = 0.71; P < 0.0001), and the main parameter of interest in this study was the mean parental age at childbirth (MPAC), calculated as the average of maternal and paternal ages.
ResultsIncreasing MPAC was associated with a continuous increase in insulin sensitivity ( = 0.193; P = 0.008), as well as reductions in insulin resistance (HOMA-IR; = -0.064; P = 0.011), fasting insulin ( = -0.221; P = 0.018) and fasting glucose ( = -0.030; P = 0.033) concentrations. Increasing MPAC was also associated with reductions in night time systolic ( = -0.500; P = 0.020) and diastolic ( = -0.325; P = 0.047) blood pressure, as well as with improved (greater) nocturnal diastolic blood pressure dipping ( = 0.413; P = 0.046). Subgroup analyses on participants of European descent (n = 64) showed that increasing MPAC was associated with reduced carotid intima-media thickness ( = -0.008; P = 0.018) and lower low-density lipoprotein cholesterol concentrations ( = -0.042; P = 0.028).
ConclusionsIncreasing parental age at childbirth was associated with a more favorable metabolic phenotype in overweight middle-aged males. However, it is unknown whether the effect was maternal, paternal, or both. Future studies on the effects of parental age at childbirth on the metabolism of males and females across the BMI range are required. Am. J. Hum. Biol. 27:380-386, 2015. (c) 2014 Wiley Periodicals, Inc.