INS and diabetes mellitus: Based on quantitative assessments of nap time and autonomic function in 436 subjects who agreed to undergo a 75-g oral glucose tolerance test (75-g OGTT), and examinations of their interrelationship with insulin secretion and sensitivity, the present study aimed to explore the possibility that nap time and autonomic function are related to diabetes onset, whether napping as a supplement to short nighttime sleep is associated with insulin secretion and sensitivity, thus providing important information to help with early intervention for its prevention.