This paper analyses the output signal-to-noise ratio for a standard noise reduction scheme and for an integrated active noise control and noise reduction scheme, both applied in the hearing aid framework including the effects of signal leakage through an open fitting and secondary path effects. In particular, a standard noise reduction scheme based on the multichannel Wiener filter and an integrated active noise control and noise reduction scheme based on the filtered-X multichannel Wiener filter are analysed and their signal-to-noise ratio are derived under a single speech source scenario.