Patterns of Changes in Abdominal Obesity Indices in Prediabetic Individuals: Results of a 16-year Prospective Cohort Study among First-degree Relatives of Type 2 Diabetic Patients

Introduction: Previous studies have not investigated the association of concomitant changes in obesity indicators with diabetes in prediabetic patients. This study aimed to identify the patterns of changes in the abdominal obesity indices over time in prediabetic patients and to predict high-risk individuals for the future risk of diabetes development. Materials and Methods: This prospective 16-year cohort study was conducted among 1228 prediabetic individuals during 2003-2019. The subjects were followed-up over time, and changes in their abdominal obesity indices were evaluated. The hidden Markov model (LMM) was used for data analysis. Results: The LMM identified three hidden states, depending on changes in the abdominal obesity indices: low risk of diabetes development; moderate risk of diabetes development; and high risk of diabetes development (19%, 45%, and 36%, respectively). The probability of progression from moderate to low- and high-risk groups was 0.34 and 0.02, respectively, and the probability of staying in high- and moderate-risk groups was 0.98 and 0.78, respectively. Conclusion: Based on our long-term evaluation of patterns of changes in the abdominal indices, we classified prediabetic individuals into high, moderate, and low risk groups of diabetes development in the future. Due to the low probability of transition from the high risk to the low risk group in prediabetic patients, it is necessary to consider weight control as an important preventive factor in diabetes progression.