Reference Interval, Optimal Threshold Value, and Correlates of Homeostasis Model Assessment of Insulin Resistance in Healthy Normal‑weight Adults in a Nigerian Population

Abstract

Background: Currently, there is paucity of locally–established reference intervals and optimal threshold values for homeostasis model assessment of insulin resistance (HOMA‑IR) in Nigeria.

Aims: The aim of this study was to determine the normative values and correlates of HOMA‑IR among apparently healthy adults in a Nigerian population.

Materials and Methods: A cross-sectional study was carried out among 210 healthy, normal-weight adults aged 18–64 years.   Anthropometric, physical, and biochemical measurements were carried out including fasting plasma glucose and fasting plasma insulin   levels. The HOMA‑IR was calculated using a mathematical formula. The reference intervals and optimal threshold values for the HOMA‑IR  were derived using the nonparametric percentile method.

Results: A total of 210 healthy normal-weight, nondiabetic adults, 110 males (52.4%) and 100 females (47.6%) participated in the study.  The 2.5th, 75th, 90th and 97.5th percentile values of the HOMA‑IR for total (n = 210), male (n = 110), and female (n = 100) study  participants were 0.02, 1.2.28, 2.18 and 2.56; 0.02, 1.19, 2.0 and 2.54; 0.24, 1.66, 2.25, and 2.58 respectively. The 2.5th to 97.5th reference  intervals for HOMA‑IR for total (n = 100) were 0.02–2.56, 0.02–2.54, and 0.24–2.58 respectively. The 90th percentile optimal threshold value  for total (n = 210), male (n = 110), and female (n = 100) participants were 2.18, 2.00 and 2.25 respectively. 

Conclusion: The HOMA‑IR reference intervals and optimal threshold values in the Nigeria adult population are mostly similar to those  reported by previous studies.