How does salinity affect the bonds of an enzyme?

According to my textbook, "Too much or too little salt can interfere with the hydrogen bonds that hold an enzyme in its three-dimensional shape". I know that NaCl is held together by an ionic bond, meaning that one atom is strongly positive (in this case sodium) and one atom is strongly negative (in this case chlorine). I would guess the polarity of salt has something to do with its effect on hydrogen bonds, which consist of a hydrogen atom which bonds weakly to a strongly electronegative atom, resulting in a similar behavior to its ionization in glass of water, since water molecules are also polar and form hydrogen bonds with one another.

My question is, how exactly does salinity affect the bonds of an enzyme?

Sodium Chloride is not "polar". It is an ionic compound and dissociates into the respective ions in water (because of the latter's high dielectric constant).

Hydrogen bonds are similar to of dipole-dipole interactions (van der Waals) but much stronger and are therefore classified as a separate type of bond. However excess salt can lead to ion-dipole interactions (which are stronger than H-bond) that may prevent the formation of the hydrogen bond.

Ions such as Cl - can act as chaotropes (cause disorder)[ref]. K+ is also chaotropic while Na+ is kosmotropic (reduces disorder). However both Na+ and Cl - affect the entropy of water very slightly. So the effect of NaCl should be mostly due to ion-dipole interactions.