In order to get an in-depth understanding of patient experience, researchers developed a conceptual model of congenital thrombocytopenic purpura (TTP) that described its symptoms, effects, and disease burden. They reported their findings in The Patient — Patient-Centered Outcomes Research.
Congenital TTP accounts for 5% to 10% of cases of TTP and is characterized by thrombocytopenia, enhanced platelet aggregation, and multiorgan dysfunction. Currently, direct patient reports of living with the disease are scarce.
The researchers created an initial conceptual model by conducting a targeted literature review of publications discussing the signs, symptoms, and both direct and indirect effects or TTP. They refined this model by interviewing 5 clinical experts and 11 patients with congenital TTP.
Patients described the duration, frequency, and severity of the symptoms and effects they experienced. Symptom severity and influence on quality of life was rated on a scale from 0 (no effect) to 10 (causes great disturbance). Salience of each variable was measured as a combination of frequency and severity.
According to the literature review, the most common signs of TTP were thrombocytopenia, microangiopathic hemolytic anemia, neurologic symptoms, renal failure, and fever. Common symptoms included bruising, chest pain, confusion, fatigue, partial paralysis, and vision problems. These findings were mostly supported by the clinician interviews, though the researchers noted that clinicians viewed partial paralysis, hypotension, heart failure, and gastrointestinal bleeding as less common than reported.
Of note, the clinicians said that congenital TTP and acquired TTP, which were not differentiated between in the literature, had unique symptom profiles “to a modest degree.”
There were several differences between the patients’ reports of their experience compared with clinical and literature reports. According to the patients, the most salient symptoms included fatigue, headache, bruising, pain, forgetfulness, and difficulty communicating. The most salient effects were emotional effects such as depression, mood swings, and financial distressed, followed by decreased ability to work or study.
The researchers noted that “patients consistently expressed a desire for safer and more convenient [treatment] options.” Furthermore, the language used by the patients was often different; for example, the symptom referred to as “confusion” in the literature was more frequently called “forgetfulness” by patients.
Because of the small sample size and involvement of only English-speaking, adult patients in the United States, the generalizability of these results is limited. However, “this [model] could help capture the [influence] of new treatments on patients’ lives,” the authors concluded.
Disclosures: Some authors have declared affiliations with the pharmaceutical industry. Please refer to the original study for a full list of disclosures.
1. Oladapo AO, Ito D, Hibbard C, Bean SE, Krupnick RN, Ewenstein BM. Patient experience with congenital (hereditary) thrombotic thrombocytopenic purpura: a conceptual framework of symptoms and impacts [published online July 30, 2019]. Patient. doi:10.1007/s40271-019-00365-y