Evaluation of kidney functions and blood pressure in eating disorder patients

Eating disorders are characterized by changes in eating or eating-related behaviors and significantly affect physical-psychological functions. Patients may develop renal complications. We aimed to determine the frequency of renal disorders and clinical and laboratory factors affecting them; 41 patients (36 female, 5 male; mean age 15,93 ± 1,47 years; mean follow-up time 12,07±12,32 months) who were followed up with the diagnosis of anorexia nervosa or bulimia nervosa according to DSM-5 between January 2020 and August 2020 at the Department of Adolescent Health, Hacettepe University Faculty of Medicine İhsan Doğramacı Children's Hospital were included. Microalbuminuria, macroalbuminuria, hypostenuria, leukocyturia (sterile), and hypercalciuria was seen in 19.4%, 2.8%, 32.5%, 7.5%, and 15.8% of cases, respectively; ultrasonographic examination did not reveal nephrolithiasis or nephrocalcinosis. Serum cystatin-C level was found to be significantly lower, compared to controls; and it was attributed to lower level of adipose tissue in the patient group. eGFR values, calculated with creatinine and cystatin-C based methods, showed that 0-9.8% of patients had an eGFR <90 ml/dk./1.73m2. Magnetic resonance imaging apparent diffusion coefficient (ADC) values were different in certain zones, compared to controls. Ambulatory blood pressure monitorization (ABPM) showed that blood pressure levels were significantly low; and this pattern was more remarkable for systolic blood pressure and during daytime. In conclusion, renal complications may develop in patients with eating disorders, even in the absence of clinical symptoms; cystatin-C, ABPM and renal imaging may be useful in addition to routine evaluation for kidneys. Long-term follow-up studies are needed to determine the values of these methods in the management of the patients.