Propofol Dosage in Patients with Insomnia Undergoing Digestive Endoscopy: A Multi-Center Prospective Propensity Score-Matched Cohort Study

Technical Summary: Propofol Dosage in Patients with Insomnia Undergoing Digestive Endoscopy

Problem Statement
Insomnia is a prevalent clinical condition affecting 10% to 30% of the population, yet its impact on anesthetic pharmacodynamics remains underexplored. Patients with insomnia face a dual risk during general anesthesia: insufficient dosing may lead to intraoperative awareness and subsequent psychological sequelae (e.g., PTSD, anxiety), while excessive dosing may cause hemodynamic instability and delayed recovery. Previous research suggested that patients with sleep disturbances require higher concentrations of sevoflurane or propofol, but existing studies were limited by single-center designs, narrow age ranges (excluding 18–44 years), reliance on screening tools rather than diagnostic criteria, and a focus solely on short-duration gastroscopy. There was a need for a robust, multi-center investigation to determine if confirmed insomnia alters propofol requirements across a broader demographic and for various digestive endoscopic procedures.

Methodology
This study was a multi-center, prospective, propensity score-matched (PSM) cohort study conducted between April 2024 and October 2025 across three hospitals in China (Beijing Tiantan Hospital, Hebei Medical University Third Hospital, and Hengshui People's Hospital).

• Study Population: Patients aged 18–65 with ASA physical status I–II and BMI 15–30 kg/m² scheduled for digestive endoscopy (gastroscopy, colonoscopy, or gastroenteroscopy).
• Grouping:
  • Insomnia Group: Diagnosed according to DSM-5 criteria with a Sleep Condition Indicator (SCI) score ≤16.
  • Normal Sleep Group: No history of insomnia per DSM-5 and SCI criteria.
• Matching: A 1:3 propensity score matching was performed based on procedure type, gender, age, BMI, and procedure duration to balance baseline characteristics. This resulted in 140 matched patients in the insomnia group and 420 in the normal sleep group.
• Intervention: Anesthesia was induced with an initial propofol dose of 1.6 mg/kg, followed by boluses of 20–30 mg as needed. Sedation depth was maintained at a Ramsay score of 5–6 using a modified Dixon's up-and-down method (MDUDM) for titration. Anesthesiologists administering and assessing sedation were blinded to the patient group and specific dosage.
• Outcomes:
  • Primary: Total propofol consumption (mg/kg).
  • Secondary: Propofol dosage for successful endoscopic insertion, recovery time, PACU stay, procedural ease, satisfaction scores, and perioperative adverse events (hypoxemia, hypotension, etc.).
  • Correlation Analysis: Linear regression was used to assess the relationship between insomnia severity (Insomnia Severity Index, ISI) and propofol dosage.

Key Results

• Propofol Consumption: After matching, the insomnia group required significantly higher total propofol consumption compared to the normal sleep group (3.8 ± 0.8 mg/kg vs. 3.3 ± 0.6 mg/kg; P = 0.003).
• Insertion Dosage: The dosage required for successful endoscopic insertion was also significantly higher in the insomnia group (2.4 ± 0.3 mg/kg vs. 2.1 ± 0.3 mg/kg; P = 0.043).
• Subgroup Analysis: The increased requirement for propofol in the insomnia group was consistent across gender and age subgroups. However, an interaction effect was observed regarding BMI; the increase in dosage was more pronounced in normal-weight patients (MD = 0.7 mg/kg) compared to overweight patients (MD = 0.3 mg/kg).
• Severity Correlation: A significant positive correlation was found between insomnia severity and propofol dosage. Patients with mild, moderate, and severe insomnia required 6.1%, 24.2%, and 36.4% more propofol, respectively, than the normal sleep group. Insomnia severity accounted for approximately 31.0% of the variance in total propofol consumption.
• Safety and Recovery: There were no statistically significant differences between the two groups regarding procedure duration, recovery time, PACU stay, or the incidence of perioperative adverse events (including hypoxemia, hypotension, and bradycardia). Satisfaction rates for both patients and gastroenterologists were high (>95%) and comparable between groups.

Significance and Claims
The authors conclude that patients with confirmed insomnia require higher propofol dosages to achieve the same depth of anesthesia and procedural success as patients with normal sleep patterns. The study suggests that preoperative anesthesia evaluations should prioritize sleep quality assessment to facilitate individualized dose adjustments.

The paper positions its findings as higher-level evidence compared to previous work (specifically citing Qiu et al.) due to its multi-center design, larger sample size, inclusion of a broader age range (18–65), use of DSM-5 diagnostic criteria, and inclusion of longer-duration procedures like colonoscopy. The authors propose a pathophysiological mechanism where dysregulation of the GABAergic system in insomnia patients necessitates higher propofol doses to achieve therapeutic receptor activation.

Limitations
The authors modestly acknowledge several limitations:

1. Lack of objective sleep evaluation (e.g., polysomnography), relying instead on self-reported scales and DSM-5 criteria.
2. Restricted inclusion criteria (ASA I–II, BMI 15–30, age 18–65), which limits generalizability to elderly, high-risk, or extreme BMI populations.
3. Restriction to digestive endoscopy, which has lower stimulation than major surgeries requiring intubation.
4. Potential unmeasured center-specific factors.
5. The need for future randomized controlled trials to validate the observed dosage increases.

The study does not claim to define a new standard of care but rather provides a theoretical basis for considering sleep quality in anesthetic planning and suggests the need for further validation.