Loss of Anthropometry-Lipids Relationship in Obese Adults: A Cross-Sectional Study in Southern China

Abstract

Background

Emerging data suggest that the interpretation of the association between obesity and lipids appears to be oversimplified. This study aimed to quantify the complex relationships between anthropometric indices and lipid profile.

Methods

This is a cross-sectional study including 9620 participants in Southern China. Anthropometric indices included the indices of general obesity (ie, body mass index (BMI)) and central obesity (ie, waist circumference (WC) and waist-to-hip ratio (WHR)). Lipids included low-density lipoprotein cholesterol (LDLc) and atherogenic lipids (ie, high-density lipoprotein cholesterol (HDLc), triglycerides (TG) and TG/HDLc ratio). LOESS regression and general linear model were the main statistical methods.

Results

Almost all associations between anthropometric indices and lipids were lost in obese adults. The loss of association occurred quicker with LDLc than that with atherogenic lipids; the break point for the association loss was at BMI of 24 kg/m² with LDLc (Slope _{Below break-point} = 1.81, P<0.001; Slope _{Above break-point} = 0.29, P=0.121), while at 28 kg/m² with HDLC (Slope _{Below break-point} = −1.41, P<0.001; Slope _{Above break-point} = 0.07, P=0.666) or TG (Slope _{Below break-point} = 4.96, P<0.001; Slope _{Above break-point} = 2.93, P=0.01), and at 30 kg/m² with TG/HDLc ratio (Slope _{Below break-point} = 0.15, P<0.001; Slope _{Above break-point}= 0.01, P=0.936), respectively. Similar relationships were found for WC and WHR. Besides, the presence of other metabolic disorders contributed to the loss of anthropometry-lipids relationships, for example, the BMI-LDLc association attenuated to null in both obese adults and non-obese population but with more than one other metabolic disorders.

Conclusion

The relationships were lost between anthropometric indices and lipids in obese adults with different break points across different lipids, which appeared to be dependent on metabolic status.

Keywords:

• anthropometry
• lipid profile
• epidemiology

Abbreviations

BMI, body mass index; CI, confidence interval; LDLc, low-density lipoprotein cholesterol; HDLc, high-density lipoprotein cholesterol; LOESS, locally weighted scatterplot smoothing; TG, triglycerides; WC, waist circumference; WHR, waist-to-hip ratio.

Data Sharing Statement

Data described in the manuscript, code book, and analytic code will be made available upon reasonable request to the corresponding authors.

Ethics Approval and Consent to Participate

The study has been approved by the Ethics Review Committee of Fujian Medical University (approval number, [2017-07] and [2020-58]). All procedures were performed following the guidelines of the Declaration of Helsinki. All participants in Fuqing cohort provided written informed consent.

Acknowledgments

We thank the participants and investigators who contributed to the Fuqing cohort.

Disclosure

The authors declare no conflicts of interest in this work.

Additional information

Funding

This study was jointly supported by the Government of Fuqing city [grant number: 2019B003], Ministry of Science and Technology of the People’s Republic of China [grant number: 2017YFC0907102], Department of Science and Technology of Fujian, China [grant number: 2019L3006, 2019Y9021], and High-level Talents Research Start-up Project of Fujian Medical University (No. XRCZX2021026, No. XRCZX2017035 and No. XRCZX2020034). The funders had no role in the study design, data collection and interpretation, or the decision to submit the work for publication.