I assume the OP is referring to "how long do the symptoms last" instead of what she asked. Menopause is 'til death--your periods aren't going to come back. If you get a period after the obligatory year it probably signals something is wrong.
I'm probably a couple years past menopause and I'm mopping up the aftermath of the wrath and the toll perimenopause and then the complete cessation of periods took on my health. I like many had very few health ills (certainly nothing like the night and day difference of losing my hormone balance). I refuse to call it aging, because after all these months, weeks and days I am slowly working my way back to something resembling "MY SELF." It's me that became lost while feeling like a hypochondriac during the four ER visits in less than a year. I used to think people who SAID they had panic attacks were making it up for the sake of drama.
So during my odyssey, I found out I had sleep apnea and it's been treated now with CPAP (thankfully someone invented that) for nearly three years. I urge any woman 35-40 who is having sleep issues of any kind to get screened for sleep apnea. I was offered hormones--it would have been the exact wrong thing in my case. I know my mother had sleep apnea and I found out that her mother had it--according to my uncle. No one knew about sleep apnea in the 80s when we would watch my mom stop breathing periodically during a nap. And the treatment originally was pretty drastic (tracheostomy) until the advent of CPAP therapy.
My family history is rife with hypertension and strokes and sleep apnea can cause hypertension or at least contribute. Some people get full relief from hypertension after getting their sleep apnea treated.
The other biggie for me is regular coffee. I know it contributed to my panic attacks (as did peanut butter, which I was not previously sensitive to nor allergic to). After a couple years I have not incorporated peanut butter back into my diet--I don't really miss it, but would like to give it that old college try because I think it's a good source of quick energy. So back to coffee--I'm so much better off without it. I found that even early in the morning even one cup interfered with my sleep duration. Now that I've been away from it--the sleep is worth much more than the pleasure of the coffee. (I hate it, but it's the truth.)
I used to be a multiple pots of coffee drinker in my 20s, 3-5 cups in my 30s and 1-2 cups in my 40s. I know what I'm in for now when I risk going to a restaurant and asking for a cup of decaf in the late afternoon--it's usually not decaf. So if I have it, I have to make it myself and be sure it's decaf.
Coffee = misery later in the night for me now. I hate it, but I'm still kind of grieving the loss, so I think in time I'll be okay.
The other thing that makes a huge difference to me is exercise and specifically regular weight training. The loss of muscle is very pronounced in the last half year or so. I monitor my body fat and it's just not an easy task to get back to that old body. In fact the old body is GONE--another thing to grieve! I have to think in terms of this one that the alien lifeforce known as MENOPAUSE overtook the me I knew and loved. I will slough off that sense just as my uterine lining was sloughed off every month for years. It's going to take time and I know I'm in for the fight of my life.
After many months I know what I have to do and my confidence that I can do it is fairly good. It's a matter of sticking with a great diet (a sea change) and at least an hour of exercise daily. I've been at least that active for the last 20 years, so that's not foreign to me. I thought that being in pretty good shape would hold me in good stead for an easy menopause--how wrong I was. I was simply blindsided. However, I know many women in their 70s and they're my best friends--they got through it and some have thrived and so I look forward to doing the same!