That is absolutely the case, and I have experienced it first hand myself. One of the symptoms of dehydration is joint pain and muscle cramps. These symptoms can be eased somewhat by drinking lots of water - at least for me. Aside from pg, vg is also a dehydrating agent - although to a lesser extent. Therefore more water in your juice is always a good idea. Some vendors even sell their liquids in a version that contains 80%vg and 20%DW.
I'd be interested to know if anyone besides myself has experienced joint pain and muscle cramps attributable to vaping and/or dehydration.
Yeah, I've gotten symptoms like that from dehydration. You may need more electrolytes, too. Often, things that cause dehydration also lower electrolyte levels. Bananas can be good for that, especially if you're getting muscle cramps. I've read about people using saline solutions in their bases with pg,vg and distilled water, but I haven't tried this myself. This is more of a localized treatment, but I use saline spray in my nose throughout the day especially when I'm vaping at high watts. It helps reduce irritation in my throat and keeps my nose from getting too dried out.