A systematic literature review of frequency of vaso-occlusive crises in sickle cell disease

Abstract

Background and purpose Sickle cell disease (SCD) is a collection of rare inherited blood disorders affecting approximately 100,000 people in the U.S. and 20–25 million people globally. Individuals with SCD experience recurrent episodes of severe and unpredictable pain that are caused by vaso-occlusive crises (VOCs), a hallmark of the disease. VOCs are the primary cause of hospitalization in SCD, result in missed workdays and school days, and decrease quality of life (QoL). Although VOCs cause significant burden in the lives of individuals with SCD, there is no synthesis on the frequency of VOCs in the real world. This systematic literature review sought to identify literature describing the frequency of VOCs experienced by individuals with SCD in real-world settings. Methods MEDLINE and 6 congresses were searched (date range: January 1, 2000 to June 30, 2020). Studies were reviewed independently by two researchers. Studies assessing frequency or prevalence of VOCs or VOC-related outcomes were included. Results Of 1438 studies identified in the search, 52 met pre-specified inclusion and exclusion criteria. Reported frequency of VOCs varied widely ranging from a mean or median of 0 VOCs/year to 18.2 VOCs/year. The proportion of patients experiencing ≥ 3 VOCs/year ranged from 4 to 67% and the proportion of patients experiencing ≥ 5 VOCs/year ranged from 18 to 59%. Measures of VOC severity were limited, with 13 studies considering frequency of complicated VOCs and only 1 study reporting duration of VOC episodes. Conclusions This is the first study to systematically assess published evidence pertaining to VOCs in real-world settings. Reported VOC frequency in real-world settings varied widely, with a majority of studies only considering VOCs managed in an inpatient or outpatient setting. Studies that considered VOCs managed at home reported a higher frequency of VOCs, suggesting that many studies may underestimate the frequency of VOCs. This systematic literature review (SLR) highlights the need for consistent reporting of (1) self-reported VOCs, including those managed at home, (2) definitions of VOCs, (3) complicated VOCs, and (4) duration of VOC episodes in literature.

Characterisation of medical conditions of children with sickle cell disease in the USA: findings from the 2007–2018 National Health Interview Survey (NHIS)

“…Children with SCD have been observed to have a lower health-related quality of life due to the impact of severe disease-related complications and comorbidity 4. These complications and comorbidity include infections, pain crisis,5–8 acute chest syndrome, metabolic deficiencies,9 overt stroke4 and even educational challenges that begin in elementary school and persist post high school,10 11 in the presence of other comorbid conditions.…”

Establishment of mouse line showing inducible priapism‐like phenotypes

“…SCD is an inherited blood disorder that affects approximately 20–25 million people worldwide. 4 , 5 SCD patients tend to develop priapism, with a prevalence of about 30%–45%. 5 , 53 The complications associated with SCD, including priapism and ED, remain debilitating to that patients.…”

“…Priapism is a common complication of sickle cell disease (SCD). SCD is an inherited blood disorder that affects approximately 20–25 million people worldwide 4,5 . SCD patients tend to develop priapism, with a prevalence of about 30%–45% 5,53 …”

“…Delayed treatment of sustained erectile disorders often leads to erectile dysfunction (ED). 4 , 5 , 6 ED is a serious reproductive problem in elderly societies and its high frequency has been recently reported in advanced countries. As such, Priapism is considered a serious pathological condition and an essential issue for the analysis of erectile processes.…”

“…Priapism is one of the serious erectile abnormalities that shows continuous erection. Delayed treatment of sustained erectile disorders often leads to erectile dysfunction (ED) 4–6 . ED is a serious reproductive problem in elderly societies and its high frequency has been recently reported in advanced countries.…”