I remember from EMT school the informal advice that spontaneous pneumo is a predisposition for certain body types and something as trivial as a burp or hiccups can cause. Tall and thin body type. But this is anecdotal- is there an underlying cause in your case?
Some medics said exactly this for me. This body type is called "franzino" in Brazil and is exactly how I was as a teenager. Strangely my pneumathoraces were not on the same side. On the left side it happened twice which was fixed with two clamps and a pleurodesis. On the right side it occurred only once but considering my predisposition, there's no reason to think it will never happen again.
Imagine walking around knowing your lungs could pop for essentially no good reason, at any moment.