Trends in tolvaptan prescription and the association between hypernatremia and aging in tolvaptan-treated patients in Japan: Real-world data mining using Japanese databases.

Objective: To identify the trends in tolvaptan prescription and the association between aging and tolvaptan-induced hypernatremia.

Materials and methods: A health insurance claims database and a spontaneous adverse drug reaction database were used.

Results: Of all patients who had been prescribed tolvaptan, the proportion of patients aged 60 - 79 years and ≥ 80 years was consistent at ~ 40%. Moreover, the prescription frequency of tolvaptan increased over time for patients in the same age groups. The adjusted reporting odds ratio of tolvaptan-induced hypernatremia was 5.54 (95% confidence interval, 3.31 - 9.25) in patients aged ≥ 60 years from among all patients and 2.09 (95% confidence interval, 1.59 - 2.75) in those aged ≥ 80 years from among those aged ≥ 60 years.

Conclusion: It may be necessary to be aware of hypernatremia in elderly patients who are expected to have increased prescriptions of tolvaptan.