Discussion
In the present post-marketing surveillance study with a large
sample size (1,057 patients as a cohort), the efficacy of tolvaptan,
including decrease in body weight, increase in urine volume,
and improvement of congestive symptoms, was reconfirmed
in the real-world clinic setting to be similar to that observed in
previous clinical trials. Serum sodium levels were elevated by
tolvaptan in hyponatremic patients at BL, but tolvaptan did not
significantly increase the serum sodium levels among the normonatremic
patients.