Briefly, data mining provides several advantages in this field, such as detection of the fraud in health insurance. It also helps in detecting reasons of diseases and then recognizing medical treatment methods.
I'm applying different data mining and machine learning techniques for processing different Neurological signals and Physiological measures. Please check this link
https://www.researchgate.net/profile/Samer_Sarsam
in order to have an idea about my available publications.
Most common application of big data techniques in health care is DNA or sequence matching. There are lot of tools based on Hadoop or spark which are used in sequence alignment. CloudBurst , CloudAligner and SparkBWA are most commonly used tools.
there are several health related datasets available publicly, you can look at them and try applying machine learning/modeling. they will serve as an excellent starting point