When it says that the article is relevant to P4 and P5 it means that it can be asked in both papers, so you should not ignore it!! (It is more relevant to P5 but even so any part of it can be asked in P4).
Risk management for P4 includes several topics and there is quite likely to be more than one examined – foreign exchange risk; interest rate risk; value at risk; CAPM; delta hedges (options); are all risk management topics.