ok im not sure if that question was directed towards negative or positive effects...
vapor released by a vaporizer is much more pure then smoke also more potent
almost no tar at all is vaporized as the vaporizer does not get up to a high enough heat to do so
depending on the quality of the vaporizer will decide the quality and purity of the vapor
because of your lung and bronchial problems (thanks wiki) i would say this would eliminate the majority of negative effects that would be encountered with the traditional rout of burning the weed
i would recommended investing in a GOOD vaporizer as to lower your chance of problems
at least spend around $300-400