Cloud computing technology significantly emerged in various systems to enhance the platform and infrastructure of services. Fog and Edge computing technologies transform computing power and processing close to the end-user and resolve many data processing challenges. Healthcare IoT systems refer to using medical sensors and mobile computing to manage patients’ conditions and use cloud-based technologies to transfer collected patients’ data to the cloud computing storage. Many previous research efforts focused on the use of edge, fog, and cloud computing technologies in the field of healthcare IoT systems. However, no previous research study summarized the main research topics and trends in these research efforts. To that end, we conducted a systematic and comprehensive empirical research study to understand the main research topics and the employed computing technologies and trends in these research topics. This study investigated 100 research studies focusing on cloud-based technologies in the filed of healthcare IoT systems published in highly reputable venues over the past decade. We created a taxonomy of the main research topics of the investigated research manuscripts and reported the main focus of these research efforts and the trends in this field. Our investigation concluded that the researchers mainly focused on the following five research topics: big data, security, network latency, energy efficiency, and QoS. However, some research topics are well studied while others are poorly investigated and need more attention. We found that the highest number of research papers focused on big data, i.e., 63% of the studied papers, while the energy efficiency topic had the lowest number of papers, i.e., 17% of the papers. Researchers and practitioners interested in the cloud-based healthcare IoT systems can use our findings to gear their work on the areas that are poorly investigated to find better solutions.