I'm not an expert in american insurance policies (not even a novice, tbh) but if you have an ongoing condition and then lose insurance, and then get new insuran

I'm not an expert in american insurance policies (not even a novice, tbh) but if you have an ongoing condition and then lose insurance, and then get new insurance with your easy-to-get new job then would the ongoing condition be considered a pre-existing condition and hence fall into question regarding cover?