Related Experiment Video
Updated: Jun 9, 2026
Predicting Amputation using Local Circulating Mononuclear Progenitor Cells in Angioplasty-treated Patients with Critical Limb Ischemia
Published on: September 22, 2020
Predicting major ischemic priapism: a novel dynamic nomogram based on recurrent ischemic priapism risk factors
Laurence T Hou1, Yuezhou Jing2, Bruce J Trock2
1Department of Urology, Hackensack University Medical Center, Hackensack, NJ 07601, United States.
Background:
Recurrent ischemic priapism (RIP) is a repetitive, self-remitting subtype of ischemic priapism with high risk of progression to major ischemic priapism (MIP), which can cause irreversible fibrosis and erectile dysfunction.
Aim:
To identify the risk factors for MIP in patients with RIP and develop a prognostic model and a RIP severity scoring system to predict future MIP events.
Methods:
We conducted a retrospective chart review of patients with RIP across a major academic health system (May 2006-November 2020). Demographic, clinical, and priapism characteristics were collected, and univariate and multivariable Poisson regression analyses were performed to identify predictors of MIP events per person-year (MIP PPY). Internal validation was performed using 10-fold cross-validation with mean absolute error as the performance metric. A web-based dynamic nomogram was created from significant risk factors, and patients were risk-stratified based on predicted MIP PPY.
Outcomes:
Primary outcome was the incidence rate ratio of MIP PPY predicted by significant risk factors.
Results:
Among 113 patients (mean age 32 years, mean follow-up 3 years), 225 MIP events were recorded over 557.5 person-years. Multivariable analysis identified longer priapism duration, adult-onset RIP (>25 years old), sickle cell disease, marijuana use, and tobacco smoking as independent predictors of increased MIP PPY. Patients were classified post hoc as low-risk (<1 MIP PPY, n = 81) or high-risk (≥1 MIP PPY, n = 32), with high-risk patients exhibiting longer priapism episodes, older age of onset, and higher recurrence rates.
Clinical Implications:
The nomogram offers an investigational tool for individualized risk estimation that, if validated, may help identify patients at higher risk of MIP and inform future study of preventive strategies.
Strengths And Limitations:
Strengths include the largest RIP cohort reported to date, robust statistical modeling, and creation of an interactive nomogram. Limitations include retrospective single-institution design, potential underreporting of priapism events, and lack of external validation, which may limit generalizability.
Conclusion:
This study identifies key MIP risk factors in patients with RIP, introduces a novel dynamic nomogram to predict future MIP events, and proposes a RIP severity scoring system that may improve risk stratification, inform treatment decisions, and guide future prospective studies.
Insights
Recurrent ischemic priapism (RIP) can progress to major ischemic priapism (MIP). This study identified risk factors like longer duration, adult onset, sickle cell disease, marijuana, and tobacco use to predict MIP events.
Area of Science:
- Urology
- Andrology
- Men's Health
Background:
- Recurrent ischemic priapism (RIP) is a condition with a high risk of progressing to major ischemic priapism (MIP).
- MIP can lead to irreversible penile fibrosis and erectile dysfunction.
- Identifying risk factors for MIP in RIP patients is crucial for timely intervention.
Purpose of the Study:
- To identify independent risk factors for major ischemic priapism (MIP) in patients experiencing recurrent ischemic priapism (RIP).
- To develop a prognostic model and a severity scoring system for predicting future MIP events.
- To create a dynamic nomogram for individualized risk stratification of RIP patients.
Main Methods:
- Retrospective chart review of 113 patients with RIP from May 2006 to November 2020.
- Multivariable Poisson regression analysis to identify predictors of MIP events per person-year (MIP PPY).
- Internal validation using 10-fold cross-validation and development of a web-based dynamic nomogram.
Main Results:
- Longer priapism duration, adult-onset RIP, sickle cell disease, marijuana use, and tobacco smoking were identified as independent predictors of increased MIP PPY.
- Patients were stratified into low-risk (<1 MIP PPY) and high-risk (≥1 MIP PPY) groups.
- High-risk patients had longer episodes, older age of onset, and higher recurrence rates.
Conclusions:
- A novel dynamic nomogram was developed to estimate individualized risk for MIP in RIP patients.
- The study proposes a RIP severity scoring system to aid in risk stratification and treatment decisions.
- Further validation is needed, but the nomogram may help identify high-risk patients and inform preventive strategies.
