Me too . I started going down in Late October every year. Thought it might have to do with the heating system or sunlight. This lead me to think about environmental triggers.
. Dr's said this could be seasonal affective disorder. I tried ssri and a sunlamp no effect at all and my symptoms were more physical felt like I had the flu all the time which lead to the end of my career in March 2010.
I just turned the heat off and it is only 52. But I am going nuts today. May go through a hotel. Tempted to take prednisone but I know that is not the answer. Tried on 2 shirts and reacted to them . Ugh!
I am affected by low sunlight too.... def have to take extra vitamin d in the winter... also use sunlamp... same here w the chronic flu... it's the worst
Algal DHA (DHA from algae vs fish oil) is a great anti inflammatory and also clears toxins from the glymphatic system (the brains lymphatic system)... started taking it again this week
Also, I just started taking pancreatic enzymes, wobenzym, which are amazing for pain and stiffness... I have to take a high dose, so it gets expensive..., after trying a million things, I highly recommend DHA and wobie for pain & inflammation, not a cure all, but best thing