Does Cardiorespiratory Fitness Modify the Association between Birth Weight and Insulin Resistance in Adult Life?

Tomoko Aoyama,Shizuo Sakamoto,Kazuyo Tsushita,Takeyuki Numata,Motohiko Miyachi,Izumi Tabata,Nobuyuki Miyatake,Zhen-Bo Cao,Mitsuru Higuchi,Pratibha V Nerurkar

doi:10.1371/journal.pone.0073967

Abstract

ObjectiveLower birth weight is associated with higher insulin resistance in later life. The aim of this study was to determine whether cardiorespiratory fitness modifies the association of birth weight with insulin resistance in adults.MethodsThe subjects were 379 Japanese individuals (137 males, 242 females) aged 20–64 years born after 1943. Insulin resistance was assessed using a homeostasis model assessment of insulin resistance (HOMA-IR), which is calculated from fasting blood glucose and insulin levels. Cardiorespiratory fitness (maximal oxygen uptake, VO2max) was assessed by a maximal graded exercise test on a cycle ergometer. Birth weight was reported according to the Maternal and Child Health Handbook records or the subject’s or his/her mother’s memory.ResultsThe multiple linear regression analysis revealed that birth weight was inversely associated with HOMA-IR (β = −0.141, p = 0.003), even after adjustment for gender, age, current body mass index, mean blood pressure, triglycerides, HDL cholesterol, and smoking status. Further adjustments for VO2max made little difference in the relationship between birth weight and HOMA-IR (β = −0.148, p = 0.001), although VO2max (β = −0.376, p<0.001) was a stronger predictor of HOMA-IR than birth weight.ConclusionsThe results showed that the association of lower birth weight with higher insulin resistance was little modified by cardiorespiratory fitness in adult life. However, cardiorespiratory fitness was found to be a stronger predictor of insulin resistance than was birth weight, suggesting that increasing cardiorespiratory fitness may have a much more important role in preventing insulin resistance than an individual’s low birth weight.

Highlights

Low birth weight, a proxy for fetal underdevelopment, is associated with increased risk of insulin resistance [1,2,3,4,5], type 2 diabetes [6], and metabolic syndrome [1,5] in adults
Only one study by Laaksonen et al (2003) has investigated whether cardiorespiratory fitness (CRF) in adult life can improve insulin resistance associated with low birth weight [5], and the investigators demonstrated that higher levels of CRF modify the association between low size at birth, as assessed by the ponderal index, with insulin resistance, which was estimated using a validated insulin sensitivity index (QUICKI) in middle-aged men
Low birth weight may be a cause of type 2 diabetes and metabolic syndrome later in life, while genetic and early environmental factors are of importance in the development of insulin resistance

Summary

Introduction

A proxy for fetal underdevelopment, is associated with increased risk of insulin resistance [1,2,3,4,5], type 2 diabetes [6], and metabolic syndrome [1,5] in adults. Type 2 diabetes as well as metabolic syndrome has become a major health problem worldwide, and the identification of lifestyle factors able to improve the insulin resistance accompanied by low birth weight is important to achieve primary prevention of these metabolic disorders. Only one study by Laaksonen et al (2003) has investigated whether CRF in adult life can improve insulin resistance associated with low birth weight [5], and the investigators demonstrated that higher levels of CRF modify the association between low size at birth, as assessed by the ponderal index (kg/ m3), with insulin resistance, which was estimated using a validated insulin sensitivity index (QUICKI) in middle-aged men. The aim of this study was to examine the association of birth weight with insulin resistance and to assess how the association is influenced by CRF in Japanese adults, whose birth weights are generally much lower than those of Westerners [14]

Methods

Results

Conclusion