Two classes of the drug for enlarged prostate -- 5-alpha reductase inhibitors and alpha blockers -- showed no difference in depression risk, according to a study by the Korea Institute of Drug Safety and Risk Management.

Alpha blockers such as alfuzosin and 5-alpha reductase inhibitors are the most popular treatments for benign prostatic hyperplasia (BPH).

Finasteride, one of 5-alpha reductase inhibitors, had safety issues when the European Medicines Agency ordered its manufacturers to add depression risk in approval condition in August 2017. In September 2017, the Ministry of Food and Drug Safety revised local approval condition for the treatment as well.

The Korea Institute of Drug Safety and Risk Management compared the risk of depression between 1,461 patients who took 5-alpha reductase inhibitors and 18,650 treated with alpha blockers, based on insurance claims data from the Health Insurance Review and Assessment Service from June 1, 2011, to June 30, 2017.

The depression risk of 5-alpha reductase inhibitors was 0.91 times (95 percent CI: 0.61-1.36), showing no meaningful difference from that of alpha blockers.

Anxiety disorder risk of 5-alpha reductase inhibitors was 0.96-fold (95 percent CI: 0.71-1.28), and extensive depression risk, 0.83 times (95 percent CI: 0.68-1.02).

The assessment confirmed that depression risk of 5-alpha reductase inhibitors was similar to that of alpha blockers.

However, the drug safety institute noted that it could not rule out a risk of depression during medications. “It is necessary to observe more closely the occurrence of depressive symptoms and to monitor domestic and overseas safety trends,” it said.

The study was meaningful that it was based on the national health insurance claims data -- real-world data collected from clinical fields, the institute said.

However, the study had limitations because it did not reflect unmeasured factors such as severity of illness and various test values, it added.