Marijuana use associated with faster kidney function decline in patients with CKD

SAN DIEGO — Patients with baseline chronic kidney disease who used marijuana experienced more rapid eGFR decline, according to data presented at the ASN Kidney Week 2018.

“It is important to study marijuana in light of the fact of global legalization and increasing usage,” Joshua L. Rein, DO, from Icahn School of Medicine at Mount Sinai, told Healio Nephrology. “It is important to know its effects on kidney disease.”

Rein and colleagues badyzed data from the ASSESS-AKI parallel matched cohort study to investigate whether marijuana use was badociated with kidney function decline and albuminuria. A total of 1,599 hospitalized adults who presented to one of four centers in the United States between 2009 to 2015 with or without AKI were included in the badysis. Of these patients, 113 (7%) were marijuana users. Marijuana users were defined as those who reported using marijuana since their last study visit. Participants were followed for a median of 4.1 years.

Marijuana users were more likely to be younger (mean age, 54 vs. 65 years), white (78%), men (78%) and heavy tobacco users, which was defined as smoking 20 or more cigarettes per day (26% vs. 8%).

Data indicated marijuana users had a higher baseline eGFR than non-users (87 ± 30 mL/min/1.73 m² vs. 69 ± 26 mL/min/1.73 m²); however, baseline UACR was similar among the two groups (120 ± 80 in users vs. 99 ± 72 in non-users).

Marijuana use was not linked to incident CKD (adjusted HR = 0.93; 95% CI, 0.5-1.8) or differences in eGFR slope over time (mean difference, -0.12 mL/min/1.73 m² per year among participants with a baseline eGFR of 60 mL/min/1.73 m² or more). Conversely, eGFR declined more rapidly among marijuana users with a baseline eGFR of less than 60 mL/min/1.73 m² compared with non-users (-3.2 vs. -1.4 mL/min/1.73 m² per year). Marijuana users with a baseline eGFR of less than 60 mL/min/1.73 m² also had a higher risk for CKD progression (aHR = 2.7; 95% CI, 0.83-8.5).

Among participants with vs. without CKD, marijuana use was not correlated with the rate of change in UACR.

“In this study, we saw that patients with baseline kidney disease who used marijuana had accelerated decline in their renal function compared to people who did not use marijuana,” Rein said. “Renal function in marijuana users with kidney disease should be closely monitored. We don’t know the reason for the decline in kidney function. I hypothesize it’s because of smoke inhalation. Medical marijuana in the form of vaporization or edibles may not share these same harms.”

“Patients with kidney disease experience significant symptom burden, such as nausea, anorexia and chronic pain, which are all valid issues for medical marijuana usage,” he continued. “If patients with kidney disease are prescribed marijuana for their symptoms, we need to be mindful of the effects on the kidney.” – by Alaina Tedesco

Reference:

Rein JL, et al. Abstract FR-PO233. Presented at: ASN Kidney Week; Oct. 23-28, 2018; San Diego.

Disclosure: Healio Nephrology was unable to confirm relevant financial disclosures at the time of publication.