Obesity associated with adverse ITP outcomes
21 Dec 2022
bởiAudrey Abella
In a study presented at ASH 2022, obesity was found to be associated with adverse outcomes in individuals with primary immune thrombocytopenia (ITP; formerly known as thrombocytopenia purpura).
Obesity is a growing public health problem and is tied to a myriad of health consequences. “However, the relationship between obesity and primary ITP has not been well established,” said Dr Zhengrui Xiao from the Montefiore Medical Center, Albert Einstein College of Medicine, Bronx, New York, US.
“[In our study,] higher BMI was associated with lower initial and nadir platelet counts, higher likelihood of requiring therapy, need for more lines of therapy, and a trend for more steroid dependency,” Xiao said.
Data on 275 adults diagnosed with primary ITP were retrospectively evaluated. Individuals with secondary ITP (ie, active or chronic viral infection, positive rheumatologic serology, connective tissue disorder, lymphoproliferative disorder, H pylori infection, pregnancy-induced, medication-related, COVID vaccine-induced) were excluded to minimize confounding factors.
Participants were stratified into four groups based on the BMI classification by the WHO Consultation on Obesity: regular weight (<25 kg/m2), overweight (25–29.9 kg/m2), obese (30–35/40 kg/m2 [with/without complications*]), and morbidly obese (>35/40 kg/m2 [with/without complications]). [ASH 2022, abstract 20]
Obese individuals had markedly lower mean platelet levels at diagnosis when compared against those who were non-obese (57.0 × 109/L vs 80.8 × 109/L [regular weight] and 61.5 × 109/L [overweight]). This trend was similarly seen at nadir (42.8 × 109/L vs 65.2 × 109/L and 46.9 × 109/L). Among those who were morbidly obese, the platelets levels were substantially lower as well (20.5 × 109/L both at diagnosis and nadir).
As BMI went higher, so did the percentage of patients requiring treatment to maintain their platelet levels (34.6, 53.8, 68.6, and 87.2 percent for regular weight, overweight, obese, and morbidly obese groups, respectively).
The mean number of treatment lines increased as BMI went up (1.7, 2.5, 2.8, and 2.6, respectively), as did the percentage of patients who were steroid-dependent (14.8, 21.4, 35.4, and 41.5 percent).
“Among individuals who received corticosteroids as first-line therapy, we also observed that a higher BMI was associated with shorter duration of remission,” said Xiao. The median duration of remission in the regular weight category was not reached. For those who were overweight, obese, and morbidly obese, the corresponding durations were 11, 2, and 5 months, respectively.
“This is the first retrospective study illustrating the relationship between ITP and obesity,” said Xiao. “[Taken together, our findings imply that] obesity is a crucial risk factor for ITP … Weight loss modality [may] provide synergy for ITP-directed therapy.”
Considering the scarcity of randomized trials regarding the management of ITP patients, [Blood Adv 2019;3:3829-3866] the results may also help support clinicians and healthcare professionals in providing informed treatment decisions in the management of their patients with ITP.