Utility of an APP for the Monitoring of Irruptive Oncological Pain

Irruptive oncological pain (IOP) is defined as an exacerbation of pain in cancer patients whose base pain is stable (e.g., less than 4 on a scale of 0 to 10 for more than 12 hours a day) and is well controlled with opioids. This pain increase can appear both spontaneously and associated to a specific determining factor, be it predictable or unpredictable. The IOP tends to appear quickly (3-5 minutes) and usually have a short duration (average 30 minutes, although pain may last more than 60 minutes) and moderate intensity to elevated . The median episodes of breakthrough pain per day is of 3.

The prevalence of IOP is alarmingly high. A review study of 19 works scientists places the number of cancer patients with IOP in approximately 60%. In addition, the IOP is associated with a significant decrease in the quality of life of the patients. For example, a study conducted in different countries in Europe with 1000 cancer patients revealed that in more than 80% of the participants, the appearance of breakthrough pain completely interrupted their activities. Only 11% of the patients interviewed expressed that the IOP did not interfere in their activities. For the rest of the patients, the most affected areas were sleep and emotional well-being. In addition to these costs in the quality of life of patients with IOP, recent studies have warned of the consequences of this type of pain. Thus, an investigation carried out in the United States evidenced that three quarters of the patients interviewed had experienced important economic losses as a result of the pain, being the average direct costs associated with the IOP of $ 891 per person per month.

Aiming to choose the most appropriate study methodology for this type of pain (often unpredictable and of short duration), the investigators have reviewed the works carried out up to the moment on characteristics and treatment of the IOP. Descriptive studies on IOP tend to use a most retrospective observational methodology, which can lead to biases and inaccuracies. For example, in the most ambitious study carried out so far, 1000 patients with IOP were urged to remember the characteristics of pain episodes, such as the average intensity, the approximate average duration and the average number of events per day.

Regarding the investigations on the effectiveness of the treatment of the IOP, the studies comparing different drugs tend to perform clinical trials, while to study the response to a particular drug, seems more adequate continuous assessment of each patient during an IOP episode. This last methodology with repeated measures seems the most adequate in IOP, since the use of clinical trials with few measures (baseline, post-treatment and follow-up) has the limitation of not allowing daily monitoring of patient's pain episodes.

Although daily assessments seems to be the most suitable design for the monitoring of patients with IOP, the implementation of this type of methodology could be very expensive because requires continuous evaluation. To facilitate this, several studies have already shown that mobile applications (APP) can effectively monitor the evolution of a wide range of pathologies in the context of health. In fact, a controlled clinical study recently made found that the records eco-friendly through mobile APPs were more reliable than registers with pencil and paper.