CTE does not cause AGA but may Speed Up its Arrival in those Predisposed
I’m often asked if Chronic Telogen effluvium causes people to develop androgenetic alopecia. The answer is no – with the exception that CTE can speed up the arrival AGA if a person was predisposed to develop it anyways. The main point is that the person would likely have developed AGA at some point.

Chronic telogen effuvium is a hair shedding condition that typically develops in women age 35-70. Women report the condition to a much greater extent than men. Women develop increased hair shedding that can sometimes be quite profound yet at other times be quite minimal. The condition can go on for many years. In most cases, a trigger can’t be clearly found although there may be many best guesses. Patients with CTE may have a variety of symptoms including itching, tingling, burning and soreness when the hair is moved.
Sinclair Study of 2005
The Sinclair study is an important study which helps us provide patients with clearer answers as to whether or not CTE causes AGA. Professor Rodney SInclair studied five women diagnosed with chronic telogen effluvium and followed their photos for a minimum of 7 years. Four of the 5 women continued to shed year after year after year and shedding fluctuated in severity. However, serial photographs over time showed no visible reduction in hair density, and serial scalp biopsy specimen showed no follicular miniaturization. These 4 women showed no tendency toward development of female pattern hair loss or to spontaneous improvement. One woman however was diagnosed with female pattern hair loss.

Considering that 40 % of women in the general population develop AGA, this study has important implications. This study reminds us that CTE does not simply cause AGA and that CTE does not cause hair to thin and thin over time. For patients who have the correct genetics, CTE might speed up the arrival of AGA. Instead of developing AGA at age 47 a patient with CTE might, for example, develop visible AGA at 45. But it’s important to take note that this patient likely would have developed AGA anyways.