Prodrome and Non-prodrome Phenotypes of Bladder Pain Syndrome/Interstitial Cystitis.

OBJECTIVE

To test the hypothesis that risk factors for bladder pain syndrome/interstitial cystitis (BPS/IC) in women differ between those with and without the BPS/IC prodrome.

MATERIALS AND METHODS

Incident cases of BPS/IC and healthy controls were recruited nationally. More than half the BPS/IC cases reported subsyndromal urinary symptoms for decades before onset of BPS/IC and were identified as having the prodrome. Risk factors for BPS/IC were examined separately for cases with and without the prodrome using a set of matched controls.

RESULTS

Two risk factors distinguished 178 prodrome from 134 non-prodrome cases. One was "UTIs" in the year before BPS/IC onset, possibly a manifestation of the prodrome itself. The other was the presence of the maximal number of nonbladder syndromes (NBSs): prodrome cases were 12 times more likely than non-prodrome cases to have ≥4 NBSs. Additional risk factors for prodrome and/or non-prodrome cases were the direct association of exogenous female hormones, as well as 3 inverse associations: type 2 diabetes mellitus, multiple pregnancies, and current daily smoking.

CONCLUSION

Prodrome cases developed urinary symptoms in their early 20s (ie, the prodrome) and were at very high risk of numerous NBSs. Non-prodrome cases developed urinary symptoms in their early 40s (ie, full-blown BPS/IC) and were no more likely than controls to have the maximal number of NBSs. These findings are consistent with recent suggestions of two BPS/IC phenotypes: one with systemic and psychosocial manifestations and the other more specific to the bladder. Additionally, several risk factors identified here might be hints of related or causal nervous system pathophysiologies.