Association of obesity with the development of end stage renal disease in IgA nephropathy patients

Siqing Wang; Aiya Qin; Lingqiu Dong; Jiaxing Tan; Xiaoyuan Zhou; Wei Qin

doi:10.3389/fendo.2023.1094534

Association of obesity with the development of end stage renal disease in IgA nephropathy patients

Front Endocrinol (Lausanne). 2023 Mar 20:14:1094534. doi: 10.3389/fendo.2023.1094534. eCollection 2023.

Authors

Siqing Wang^{1

2}, Aiya Qin^{1

2}, Lingqiu Dong^{1

2}, Jiaxing Tan^{1

2}, Xiaoyuan Zhou³, Wei Qin^{1

2}

Affiliations

¹ West China School of Medicine, Sichuan University, Chengdu, Sichuan, China.
² Division of Nephrology, Department of Medicine, West China Hospital of Sichuan University, Chengdu, Sichuan, China.
³ West China School of Public Health and West China fourth hospital, Sichuan University, Chengdu, Sichuan, China.

Abstract

Background and aim: Immunoglobulin A nephropathy (IgAN) is the most common primary glomerulonephritis worldwide. We aimed to evaluate whether obesity is a risk factor for IgAN patients.

Methods: A total of 1054 biopsy-proven IgAN patients were analyzed in this retrospective study. Patients were divided into four groups according to their body weight index (BMI) at the period of renal biopsy: underweight group (BMI< 18.5, N=75), normal weight group (18.5≤BMI<24, N=587), overweight group (24≤BMI<28, N=291) and obesity group (28≤BMI, N=101). The endpoint of our study was end stage renal disease (ESRD: eGFR <15 mL/min/1.73 m² or having renal replacement treatment). Kaplan-Meier analyses and Cox proportional hazard models were performed to evaluate renal survival. Propensity-score matching (PSM) was performed to get the matched cohort to evaluate the role of obesity in IgAN patients. Besides, the effect modification of obesity and hypertension in IgAN patients was clarified by the synergy index.

Results: IgAN patients complicated with obesity had more severe renal dysfunction at the time of renal biopsy than those with optimal body weight. In addition, patients with obesity tended to have higher risk of metabolic disorders, such as hyperuricemia (64.4% vs 37%, p<0.001), hypertriglyceridemia (71.3% vs 32.5%, p<0.001) and hypercholesterolemia (46.5% vs 35.6%, p=0.036). It was observed that obesity patients had higher rate of unhealthy behaviors, such as smoking (27.7% vs 16.4%, p=0.006) and alcohol drinking (29.7% vs 19.9%, p=0.027). Although obesity was not confirmed as an independent risk factor for IgAN patients, we found that IgAN patients with obesity presented with higher incidence of hypertension, as well as lower event-free renal survival rate (log-rank p < 0.001), especially in patients with 24-h urine protein ≥ 1g (log-rank p =0.002). In addition, the synergy index showed that there was positive interaction between obesity and hypertension in IgAN.

Conclusion: Obesity is an important risk factor for IgAN patients when combined with hypertension. Hypertension appears to be common in obese IgAN patients.

Keywords: IgA nephropathy; end stage renal disease; obesity; renal outcome; renal prognosis.

Publication types

Research Support, Non-U.S. Gov't

MeSH terms

Body Weight
Disease Progression
Glomerulonephritis, IGA* / complications
Glomerulonephritis, IGA* / pathology
Humans
Hypertension* / complications
Kidney Failure, Chronic* / etiology
Obesity / complications
Retrospective Studies

Grants and funding

This study was partly supported by the National Key R&D Program of China (2020YFC2006503) and grants from the project of the National Natural Science Foundation of China (No. 81970612).