Patients, clinicians, researchers agree on key measures for ICP care: Study
Groups defined core outcomes in most common liver disease during pregnancy
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An international group of patients, clinicians, and researchers has recommended a standardized set of clinical measurements to assess outcomes in intrahepatic cholestasis of pregnancy (ICP), the most common liver disease during pregnancy, according to a study.
By clearly defining the core outcomes that best capture the impact of ICP on the mother, the birth, and the newborn, scientists and clinicians can reduce research waste and more effectively compare studies to determine which treatments are most effective in ICP.
“Inclusion of international participants and strong representation from patients demonstrates the global applicability and relevance of the outcome set to clinicians and those with lived experience,” researchers wrote. “We strongly recommend that future studies reporting pregnancy outcomes in ICP should include these outcomes as a minimum.”
Details of the process that established this consensus were reported in the study “A Core Outcome Set for Studies of Intrahepatic Cholestasis of Pregnancy: Results of International e-Delphi and Consensus Processes,” which was published in BJOG: An International Journal of Obstetrics & Gynaecology.
Studies on ICP often measure and report different outcomes
ICP is a type of cholestasis in which the flow of bile, a digestive fluid, out of the liver is slowed or stopped. This results in elevated bile levels in the blood and intense itching (pruritus).
The condition also increases the risk of complications for both the mother and the baby. These include gestational diabetes and preeclampsia, or sudden high blood pressure and organ dysfunction after 20 weeks of gestation, along with preterm birth (before 37 weeks of gestation) and stillbirth.
However, studies on ICP often measure and report different outcomes. Because of this inconsistency, it’s difficult to compare studies and determine which treatments are most effective.
To address this problem, a team led by researchers in the U.K. developed a standard list of key outcomes that all ICP studies should measure and report, known as a core outcome set (COS). Similar COS lists already exist for other pregnancy-related conditions, including stillbirth, gestational diabetes, and preeclampsia.
“Our objective was to select and define a COS for clinically relevant outcomes of pregnancies affected by ICP, incorporating the views of interested stakeholders, including researchers, clinicians, and patients,” the team wrote.
Process resulted in identification of 10 core outcomes
A total of 155 individuals from Europe, Oceania, Asia, North America, and South America participated in the process, including 121 clinicians (78%), 31 patients (20%), and three researchers (2%).
First, a systematic review of the literature identified 54 published studies reporting 86 outcomes attributed to ICP, which fell into three categories: maternal, birth, and neonatal (newborn-related).
Online surveys were then conducted to rate the 86 possible outcomes, with 64 participants taking part. Clinicians and patients generally agreed on which outcomes were most important. Still, patients rated itching-related outcomes (severity and duration) as more important than clinicians did, whereas clinicians placed greater importance on birth weight.
Participants’ written suggestions were also incorporated into subsequent survey rounds, and some items were removed when they were identified as risk factors rather than actual outcomes. In later rounds, participants rerated outcomes after seeing how others had scored them.
Through this step-by-step process, the list of outcomes was narrowed from 86 to 35, and finally to 28 key outcomes. A steering committee then removed five overlapping items to facilitate the final in-person debate.
Using this tool, which was co-developed with patients, will ensure that women’s voices are heard, and outcomes of most importance will be considered to enable standardised, [high-quality], and effective research, capable of relevant and rapid clinical impact.
At the in-person meetings, 79 stakeholders ranked the final 23 proposed core outcomes, from most to least important, across maternal, birth, and newborn outcomes. A final set of 10 core outcomes was selected, each scoring above the median importance within its category.
The core set of maternal outcomes comprised the maximum total levels of bile acids (bile’s main component) in blood, gestational age at peak bile acid concentration, and the impact of itching on maternal well-being.
“Our stakeholders rated the impact of pruritus on maternal [well-being] as a core outcome — highlighting the need to report on maternal [well-being] in addition to other outcomes,” the team wrote. Moreover, “stakeholders agreed that better measurement tools are needed to understand the impact of itching on quality of life.”
Birth core outcomes encompassed stillbirth, gestational age at birth, and spontaneous preterm birth versus induced preterm birth. Lastly, core newborn outcomes included death within seven days of birth, asphyxia (oxygen deprivation), neonatal unit admission, and the need for mechanical ventilation.
“Using this tool, which was co-developed with patients, will ensure that women’s voices are heard, and outcomes of most importance will be considered to enable standardised, [high-quality], and effective research, capable of relevant and rapid clinical impact,” the researchers wrote. “We anticipate additional benefits including a reduction in research waste” and improved “comparability across trials.”
