The present approach relates to generating one or both of a failure prediction indication for an X-ray tube or a remaining useful life estimate for the X-ray tube. In one implementation, a complexity of a regression model is selected based on the operating points utilized by an imaging system for the X-ray tube, where the regression model estimates coefficients utilized by a static tube model in estimating health (e.g., thickness) of the electron emitter of the X-ray tube, which in turn may be used in predicting remaining useful life of an electron emitter of the X-ray tube. In another implementation, replacement of an X-ray tube or a component of a filament drive circuit coupled to the X-ray tube may be detected.