LOW OSMOLAR DIET AND ADJUSTED WATER INTAKE FOR VASOPRESSIN SUPPRESSION IN ADPKD.
dominant polycystic kidney disease (ADPKD) accounts for 10% of patients with end-stage
renal disease in the United States. Vasopressin is a detrimental factor in disease
progression. This randomized trial examined the effect of a novel approach of combining
low osmolar diet and adjusted water intake on vasopressin as measured by change in
plasma copeptin, and urinary osmol... read moreality in 34 patients with ADPKD. Participants were
randomized to receive a low osmolar diet (low sodium (1500 mg/day), low protein (0.8
gram/kg body weight) diet) followed by adjusted water intake to achieve a urine
osmolality of ≤280 mOsm/L versus no intervention for two weeks duration, with
equal (1:1) allocation. Permuted block randomization was performed within strata of age
and sex. Baseline characteristics of the two groups were similar. At 2 weeks, fasting
plasma copeptin (primary outcome) declined from 6.2 ±3.05 to 5.3 ± 2.5 pmol/L
(p=0.3) in the low osmolar diet group compared to a non-significant increase from
4.7±3.6 to 5.08±4 in the control group; the change in mean copeptin level from
baseline was statistically significant between groups (p=0.009). At 2 weeks, there was a
significant decline in urine osmolality from 426 ±193 to 258 ±117 mOsm/L in
the low osmolar diet group compared to a non-significant increase from 329 ±159 to
349 ±139 in the control group. The change in mean urine osmolality level from
baseline was statistically significant between groups (p=0.007). Total urinary solute
decreased only in the low osmolar diet group and significantly differed between groups
at 2 weeks (p=0.03). The adherence rate to diet and adjusted water intake was 70% with a
mean water prescription of 2.6 liters/daily. In conclusion, we identified a step wise
dietary intervention that led to significant reduction in plasma vasopressin levels as
measured by reduction in fasting plasma copeptin and 24 hour urine osmolality in
patients with ADPKD. Furthermore, this dietary intervention led to reduction in water
required for vasopressin suppression. Long-term studies are needed to evaluate the
ability of patients to adhere to a reduced solute diet and adjusted water intake, and to
determine if the reduction in vasopressin slows ADPKD
Thesis (M.S.)--Tufts University, 2015.
Submitted to the Dept. of Clinical & Translational Science.
Advisor: Ronald Perrone.
Committee: Mark Sarnak, Jessica Paulus, and Farzad Noubary.
Keyword: Endocrinology.read less