We present a generalized theory relating the helix tilt angle in a bilayer to lipid disorder. In doing so, we consider a theory performed earlier [Biophys. Chem., 86 (2000) 79] and generalize it within a nonextensive formalism. The generalized theory provides a method to compare the rotational barriers for different helices in lipid bilayers, accounting for long-range interactions via a parameter which is called "entropic index". The results obtained could lead to point out future experiments which might shed light on lipid-protein interactions.