Higher body mass index (BMI) in the period of late adolescence is linked to early chronic kidney disease (CKD) by patients’ young adulthood, according to recent findings, and this can even be seen in seemingly healthy patients with high-normal BMI prior to age 30.¹

These results came from a new study analyzing potential connections between adolescent BMI and CKD, looking at a nationally-representative group in Israel who had been given medical evaluation prior to mandatory military service.

The research was led by Avishai M. Tsur, MD, MHA, from Hebrew University of Jerusalem’s Department of Military Medicine in Israel. Tsur and colleagues implemented a CKD registry of the country’s national health care system known as Maccabi Healthcare Services (MHS).²

“Our objective was to evaluate the association between BMI in late adolescence and early CKD during young adulthood (<45 years of age),” Tsur and colleagues wrote.

Background and Findings

The investigators determined that their primary outcome assessed would be early CKD, which they defined as study participants having stage 1 to 2 CKD and moderately or severely increased albuminuria. The participants would also be considered to have CKD with an estimated glomerular rate of filtration of 60 mL/min/1.73 m² or more.

The research team used a cohort study design, making use of the mandatory medical evaluation data accessible on Israeli adolescents in the MHS system’s CKD registry. Their research would involve adolescent individuals in the age range of 16 - 20, and they would have to be born since January 1975, and have been given medical assessments for their service.

These examinations would have occurred until the team’s cutoff point of December 2019, and the participants would have been insured by MHS. The exclusion criteria decided upon by the investigators was individuals with dysglycemia, kidney pathology, hypertension, albuminuria,or missing blood pressure or BMI data.

The research team determined subjects’ BMI and then categorized the different individuals by age- and sex-matched percentiles through use of the US Centers for Disease Control and Prevention (CDC) guidelines. A period of follow-up interactions had later occurred at the time of the subjects’ medical assessments or January 1, 2000 (whichever took place later).

This period concluded at the point of early CKD onset, mortality, the final day in which patients were insured, or August 23, 2020 (whichever happened earlier). The investigators’ last analysis of the data happened in the period between December 2021 - September 2023.

The team ended up assessing the data of 593,660 adolescent subjects among the 629,168 evaluated. There was a mean age of 17.2 years, and the subjects were reported to be identified as 54.5% male and 45.5% female.

The investigators concluded that 0.3% of these participants were shown to have been diagnosed with early CKD, with a mean follow-up of 13.4 years for those who were male and 13.4 years for those who were female. Among those in the male group, the research team found that the adjusted hazard ratios were 1.8 (95% CI, 1.5-2.2) for high-normal BMI, 4.0 (95% CI, 3.3-5.0) for those who were overweight, 6.7 (95% CI, 5.4-8.4) for those with mild obesity, and 9.4 (95% CI, 6.6-13.5) for those with severe levels of obesity.

They also found that, among the female group, hazard ratios were shown to be 1.4 (95% CI, 1.2-1.6) for those with high-normal BMI, 2.3 (95% CI, 1.9-2.8) for those who were overweight, 2.7 (95% CI, 2.1-3.6) for those with mild obesity, and 4.3 (95% CI, 2.8-6.5) for those with severe levels of obesity.

Findings that were similar were reported by the investigators when they considered subjects who were seemingly healthy, those surveyed up to 30 years, or the individuals who were free of diabetes and hypertension by the ending of the follow-up period.

“Given the increasing obesity rates among adolescents, our findings are a harbinger of the potentially preventable increasing burden of CKD and subsequent cardiovascular disease,” they wrote.

References

1. ^{Tsur AM, Akavian I, Landau R, et al. Adolescent Body Mass Index and Early Chronic Kidney Disease in Young Adulthood. JAMA Pediatr. Published online December 11, 2023. doi:10.1001/jamapediatrics.2023.5420.}
2. ^{Heerspink HJL, Karasik A, Thuresson M, et al. Kidney outcomes associated with use of SGLT2 inhibitors in real-world clinical practice (CVD-REAL 3): a multinational observational cohort study. Lancet Diabetes Endocrinol. 2020;8(1):27-35. doi:10.1016/S2213-8587(19)30384-5.}