Peer-reviewed article

Impact of childhood and parental smoking and substance use on nephrotic syndrome outcomes: a prospective cohort study.

Tanay Joshi, Cal H Robinson, Nowrin Aman, Tonny H M Banh, Josefina Brooke et al. · 24 Jul 2026

Abstract

BACKGROUND: The impact of environmental exposures such as household and adolescent smoking, alcohol use, and drug use on childhood nephrotic syndrome outcomes is unknown. Our objective was to characterize tobacco, alcohol, and recreational drug use and longitudinal associations. METHODS: Analyzing data from Insight into Nephrotic Syndrome: Investigating Genes, Health, and Therapeutics, a prospective cohort, we included children (1-18 years) diagnosed with nephrotic syndrome from 1996 to 2023. Tobacco, alcohol, and recreational drug use were self-reported at annual study visits, treated as time-varying exposures. We evaluated prevalence and quantity of exposure to each substance and associations with relapse rate, steroid-sparing medication initiation, and hospitalizations using generalized linear mixed models. RESULTS: We included 732 children with nephrotic syndrome (total of 2065 study visits). Median age at diagnosis was 3.8-years (IQR 2.7-6.3), 461 (73%) were male, and 692 (96%) were steroid-sensitive at diagnosis. Exposure to a household tobacco smoker was reported in 114 (16%) participants. Eight adolescents (1%) reported personal tobacco smoking, 33 (5%) used alcohol, and 10 (1%) used recreational drugs at any time. Personal or household tobacco smoking was not associated with relapse rate (adjusted rate ratio 1.22, 95% CI 0.96-1.54), steroid-sparing medication initiation (adjusted odds ratio 0.97, 95% CI 0.66-1.42), or hospitalization (adjusted odds ratio 0.66, 95% CI 0.31-1.37). Youth alcohol use was also not associated with nephrotic syndrome outcomes. CONCLUSIONS: Up to 5% of youth with nephrotic syndrome use tobacco, alcohol, or recreational drugs, and 16% are exposed to a household smoker. While this study was underpowered to evaluate the independent impact of personal tobacco and recreational drug use, no clear association between substance exposure and longitudinal outcomes was identified.