Does sensitivity to DHT change throughout someone's lifetime?

Yes, this can change with age. I suggest seeing a hair loss expert now to go over your condition and provide you information about your best treatment options. There are great non-invasive options like prp/progesterone and/or hair transplantation. See an expert. Best, Dr. Emer

Testosterone levels do change as you get older but it is the conversion of testosterone to DHT that results in the hair loss.  It stands to reason that if there is less testosterone then less gets converted to DHT.  If you are concerned of future hair loss you might consider making an appointment with a hair restoration physician and discuss medications to help you maintain the hair you have.

Absolutely sensitivity to DHT can change and increase in the 40s. It is strictly genetically driven. Some men have no hair loss at age 40 and have quite a significant amount of hair loss by 65. Sensitivity to DHT is genetically driven.

Testosterone levels along wiht DHT levels drop as a man ages. This alters the effects of finasteride which blocks FHT at the hair receptor site. The factor that is impacting your hair loss, is a genetic factor called apoptosis which is what limits the life span of the hairs on regions of your scalp.  See a doctor, get a HAIRCHECK test which will define the loss of your hair all over your scalp, even what you can't see, and then develop a Master Plan with the doctor for now and your future as hair loss is a life long process for men