Healthcare, as one of the major economic and social issues around the world, is of great importance to an aging society. It requires tremendous labor resources and health expense. According to the 2014 national health report in the United States, the average expense for each person was $8895, while the annual national healthcare expenditure has increased to $3.8 trillion. The personal care, home health care, and nursing home care are about 18 % of tne the total expenditure [17, 18]. Furthermore, traditional hospital-centric healthcare always needs long waiting time with a low efficiency to identify serious diseases in the early stages or deal with chronic diseases. Thus, to develop the up-and-coming healthcare solutions, such as health monitoring as well as health data processing and sharing, will be very helpful to improve disease diagnosis and reduce the health expenditure .
Recently, wearable devices (e.g., smart rings, wristwatches, bracelets, and hair caps) have attracted wide attention and are widely applied to provide healthcare service, including calorie burn during fitness, physiology parameter monitoring , and heart rate recording. Healthcare-oriented mobile social networks (H-MSNs) has emerged, and consists of heterogeneous mobile networks (e.g., WiFi, cellular network and device-to-device [D2D] communications), the ubiquitous wearable devices, and powerful servers (e.g., cloud servers). As shown in Fig. 1.5, the H-MSNs can be
Fig. 1.5 Mobile healthcare network used to collect the health information sensed by wearable devices, analyze the data of health diagnosis and monitoring, and enable the social interactions among users. For example, by wearing the dedicated wearable devices, seniors can measure their physiology information, such as body temperature, heart rate, and oxygen saturation. In the meantime, these health data can be remotely obtained by their family members and/or doctors with the use of desktops and smartphones via H-MSNs. For emergency case such as a heart problem or falling down, the patients physical situation can be automatically sent by the wearable devices to his/her family members and doctors. H-MSNs also allow users to share health condition and activity information sensed by wearable devices among friends .