That's definitely a possibility. The only thing mindfulness meditation really does is cultivate awareness. Ideally, a non-judgemental and passive awareness. That's all. It does sound kind of underwhelming at first, but you highlighted how easy it is to be unaware in the second paragraph of your original post. And whilst I can't speak for its effect on gout, being simply aware of undesirable thoughts/feelings/bodily sensations and sitting with them can often cause them to subside without much effort. But if you approach the meditation as if its a treatment, then there's already this judgement that there's these negative things you're looking to get rid of. Not only will this leave you frustrated, but it will hamper the development of that non-judgemental awareness which is the real key.