The temporal trend of placebo response in migraine prevention from 1990 to 2021: a systematic literature review and meta-analysis with regression

BACKGROUND

Migraine affects 1.1 billion people globally and is the second leading cause of disability worldwide. In clinical trials, treatment efficacy is evaluated by comparing the differential responses in the treatment and placebo arms. Although placebo response in preventive migraine trials has been studied, there is limited research examining temporal trends. This study evaluates the trend of placebo response over thirty years in migraine prevention trials and investigates the association of potential confounders, such as patient, treatment, and study characteristics on placebo response using meta-analysis with regression.

METHODS

We conducted literature searches from January 1990 to August 2021 in bibliographical databases (PubMed, Cochrane Library, and EMBASE). Studies were selected according to PICOS criteria and included randomized, double-blind, placebo-controlled trials evaluating preventive migraine treatments in adult patients diagnosed with episodic or chronic migraine, with or without aura. The protocol was registered with PROSPERO (CRD42021271732). Migraine efficacy outcomes included were either continuous (e.g., monthly migraine days) or dichotomous (e.g., ≥ 50% responder rate (yes/no)). We assessed the correlation of the change in outcome from baseline in the placebo arm, with the year of publication. The relationship between placebo response and year of publication was also assessed after accounting to confounders.

RESULTS

A total of 907 studies were identified, and 83 were found eligible. For the continuous outcomes, the change from baseline in mean placebo response showed an increase over the years (rho = 0.32, p = 0.006). The multivariable regression analysis also showed an overall increase in placebo response over the years. The correlation analysis of dichotomous responses showed no significant linear trend between publication year and mean placebo response (rho = 0.08, p = 0.596). Placebo response also varied by route of administration.

CONCLUSION

Placebo response increased over the past 30 years in migraine preventive trials. This phenomenon should be considered when designing clinical trials and conducting meta-analyses.

Expert consensus established around flexible, individualized migraine treatment utilizing a modified Delphi panel

OBJECTIVE

To characterize treatment decision-making processes and formalize consensus regarding key factors headache specialists consider in treatment decisions for patients with migraine, considering novel therapies.

BACKGROUND

Migraine therapies have long been subject to binary classification, acute versus preventive, due to limitations of available drugs. The emergence of novel therapies that can be used more flexibly creates an opportunity to rethink this binary classification. To determine the role of these novel therapies in treatment, it is critical to understand whether existing guidelines reflect clinical practice and to establish consensus around factors driving management.

METHODS

A three-round modified Delphi process was conducted with migraine clinical experts. Round 1 consisted of an online questionnaire; Round 2 involved an online discussion of aggregated Round 1 results; and Round 3 allowed participants to revise Round 1 responses, incorporating Round 2 insights. Questions elicited likelihood ratings (0 = highly unlikely to 100 = highly likely), rankings, and estimates on treatment decision-making.

RESULTS

Nineteen experts completed three Delphi rounds. Experts strongly agreed on definitions for "acute" (median = 100, inter-quartile range [IQR] = 5) and "preventive" treatment (median = 90, IQR = 15), but noted a need for treatment customization for patients (median = 100, IQR = 6). Experts noted certain aspects of guidelines may no longer apply based on established tolerability and efficacy of newer acute and preventive agents (median = 91, IQR = 17). Further, experts agreed on a treatment category referred to as "situational prevention" (or "short-term prevention") for patients with reliable and predictable migraine triggers (median = 100, IQR = 10) or time-limited periods when headache avoidance is important (median = 100, IQR = 12).

CONCLUSIONS

Using the modified Delphi method, a panel of migraine experts identified the importance of customizing treatment for people with migraine and the utility of "situational prevention," given the ability of new treatment options to meet this need and the potential to clinically identify patients and time periods when this approach would add value.

Clinical and Economic Outcomes Associated With Use of Liposomal Bupivacaine Versus Standard of Care for Management of Postsurgical Pain in Pediatric Patients Undergoing Spine Surgery

Background: Approximately 60% of hospitalized children undergoing surgery experience at least 1 day of moderate-to-severe pain after surgery. Pain following spine surgery may affect opioid exposure, length of stay (LOS), and costs in hospitalized pediatric patients. This is a retrospective cohort analysis of pediatric patients undergoing inpatient primary spine surgery. Objectives: To examine the association of opioid-related and economic outcomes with postsurgical liposomal bupivacaine (LB) or non-LB analgesia in pediatric patients who received spine surgery. Methods: Premier Healthcare Database records (January 2015-September 2019) for patients aged 1-17 years undergoing inpatient primary spine surgery were retrospectively analyzed. Outcomes included in-hospital postsurgical opioid consumption (morphine milligram equivalents [MMEs]), opioid-related adverse events (ORAEs), LOS (days), and total hospital costs. A generalized linear model adjusting for baseline characteristics was used. Results: Among 10 189 pediatric patients, the LB cohort (n=373) consumed significantly fewer postsurgical opioids than the non-LB cohort (n=9816; adjusted MME ratio, 0.53 [95% confidence interval (CI), 0.45-0.61]; P<0.0001). LOS was significantly shorter in the LB versus non-LB cohort (adjusted rate ratio, 0.86 [95% CI, 0.80-0.94]; P=0.0003). Hospital costs were significantly lower in the LB versus non-LB cohort overall (adjusted rate ratio, 0.92 [95% CI, 0.86-0.99]; P=0.0227) mostly because of decreased LOS and central supply costs. ORAEs were not significantly different between groups (adjusted rate ratio, 0.84 [95% CI, 0.65-1.08]; P=0.1791). Discussion: LB analgesia was associated with shorter LOS and lower hospital costs compared with non-LB analgesia in pediatric patients undergoing spine surgery. The LB cohort had lower adjusted room and board and central supply costs than the non-LB cohort. These data suggest that treatment with LB might reduce hospital LOS and subsequently health-care costs, and additional cost savings outside the hospital room may factor into overall health-care cost savings. LB may reduce pain and the need for supplemental postsurgical opioids, thus reducing pain and opioid-associated expenses while improving patient satisfaction with postsurgical care. Conclusions: Pediatric patients undergoing spine surgery who received LB had significantly reduced in-hospital postsurgical opioid consumption, LOS, and hospital costs compared with those who did not.

The Burden of Opioid-Related Adverse Drug Events on Hospitalized Previously Opioid-Free Surgical Patients

OBJECTIVE

Opioid analgesics are a mainstay for acute pain management, but postoperative opioid administration has risks. We examined the prevalence, risk factors, and consequences of opioid-related adverse drug events (ORADEs) in a previously opioid-free surgical population.

METHODS

A retrospective, observational, cohort study using administrative, billing, clinical, and medication administration data from two hospitals. Data were collected for all adult patients who were opioid-free at admission, underwent surgery between October 1, 2015, and September 30, 2016, and received postoperative opioids. Potential ORADEs were determined based on inpatient billing codes or postoperative administration of naloxone. We determined independent predictors of ORADE development using multivariable logistic regression. We measured adjusted inpatient mortality, hospital costs, length of hospital stay, discharge destination, and readmission within 30 days for patients with and without ORADEs.

RESULTS

Among 13,389 hospitalizations where opioid-free patients had a single qualifying surgery, 12,218 (91%) received postoperative opioids and comprised the study cohort. Of these, we identified 1111 (9.1%) with a potential ORADE. Independent predictors of ORADEs included older age, several markers of disease severity, longer surgeries, and concurrent benzodiazepine use. Opioid-related adverse drug events were strongly associated with the route and duration of opioids administered postoperatively: 18% increased odds per day on intravenous opioids. In analyses adjusted for several covariates, presence of an ORADE was associated with 32% higher costs of hospitalization, 45% longer postoperative length of stay, 36% lower odds of discharge home, and 2.2 times the odds of death.

CONCLUSIONS

We demonstrate a high rate and severe consequences of potential ORADEs in previously opioid-free patients receiving postoperative opioids. Knowledge of risk factors and predictors of ORADEs can help develop targeted interventions to minimize the development of these potentially dangerous and costly events.

Does hypnotic susceptibility influence information processing speed and motor cortical preparatory activity?

Responsiveness to suggestions while hypnotized is termed hypnotic susceptibility. An association between reaction time and hypnotic susceptibility has been demonstrated, but whether distinct changes in brain activity accompany this relationship remains unclear. We investigated the effect of hypnotic susceptibility on the speed of information processing and motor cortical preparatory activity. Twenty-one "low" (Low_HS) and fifteen "high" (High_HS) hypnotically susceptible right-handed participants performed precued simple (SRT) and choice (CRT) reaction time key-press tasks under hypnotized and non-hypnotized conditions. Force and surface electromyography data were recorded from left and right index fingers. The contingent negative variation (CNV) was derived from electroencephalography data. Mean reaction time and premotor time was shorter in High_HS participants than Low_HS participants for both simple and choice reaction time tasks. High_HS participants in the hypnotized state performed fewer errors than High_HS participants in the non-hypnotized state and Low_HS participants in either state for the SRT task. High_HS participants made fewer errors overall than Low_HS participants for the CRT task. Mean C3/C4 CNV amplitude was larger in High_HS than in Low_HS participants. Furthermore, larger CNV amplitude was associated with shorter premotor time. Our findings indicate that shorter reaction time in the high hypnotically susceptible group is associated with a greater change in brain activity during motor preparation. One interpretation is that hypnotic susceptibility and neural mechanisms of arousal and selective attention are linked.

Analysis of predictors of opioid-free analgesia for management of acute post-surgical pain in the United States

OBJECTIVES

Utilization of opioid-free analgesia (OFA) for post-surgical pain is a growing trend to counter the risks of opioid abuse and opioid-related adverse drug events (ORADEs). However, utilization patterns of OFA have not been examined. In this study, we investigated the utilization patterns and predictors of OFA in a surgical population in the United States.

METHODS

Analysis of the Cerner Health Facts database (January 2011 to December 2015) was conducted to describe hospital and patient characteristics associated with OFA. Baseline characteristics, such as age, gender, race, discharge status, year of admission and chronic comorbidities at index admission were collected. Hospital characteristics and payer type at index admission were collected as reported in the electronic health record database. Descriptive statistics and logistic regression were used to identify statistically significant predictors of OFA on patient and institutional levels.

RESULTS

The study identified 10,219 patients, from 187 hospitals, who received post-surgical OFA and 255,196 patients who received post-surgical opioids. OFA rates varied considerably by hospital. Patients more likely to receive OFA were older (OR = 1.06, 95% CI [1.03, 1.10]; p < .001), or had neurological disorders (OR = 1.24, 95% CI [1.10, 1.39]; p < .001), diabetes (OR = 1.20, 95% CI [1.08, 1.33]; p = .001) or psychosis (OR = 1.18, 95% CI [1.01, 1.37]; p = .030). Patients with obesity and depression were less likely to receive OFA (OR = 0.80, 95% CI [0.67, 0.95]; p = .010 OR = 0.85, 95% CI [0.73, 0.98]; p = .030, respectively).

CONCLUSIONS

Use of post-surgical OFA was limited overall and was not favored in some patient groups prone to ORADEs, indicating missed opportunities to reduce opioid use and ORADE incidence. A substantial proportion of OFA patients was contributed by a few hospitals with especially high rates of OFA, suggesting that hospital policies, institutional structure and cross-functional departmental commitment to reducing opioid use may play a large role in the implementation of OFA.

Improved Outcomes Associated With the Use of Intravenous Acetaminophen for Management of Acute Post-Surgical Pain in Cesarean Sections and Hysterectomies

Background

Post-surgical pain impacts many patient outcomes. Effective pain management increasingly relies on multimodal analgesia regimens in which acetaminophen (APAP) is a key component. The aim of our study was to examine the impact of oral APAP versus intravenous (IV) APAP as a component of post-surgical pain management after Cesarean sections and hysterectomies.

Methods

A retrospective analysis of the Cerner HealthFacts® database (from January, 2011 to December, 2015) was conducted to compare outcomes of Cesarean section and hysterectomy surgery patients who received oral APAP to those who received IV APAP post-surgically. Length of stay (LOS), daily morphine milligram equivalent (MME) consumption, the presence of potential opioid-related adverse events (ORADEs), and total pharmacy costs were assessed. Adjusted results were derived using inverse probability weighted regression adjustment (IPW-RA) estimators based on covariates that included demographics, comorbidities, patient clinical characteristics, and hospital characteristics.

Results

The study identified 29,124 Cesarean section patients (24,612 oral APAP; 4,512 IV APAP) and 9,767 hysterectomy surgery patients (5,586 oral APAP; 4,181 IV APAP). Compared to the oral APAP group, the IV APAP group had reductions in adjusted LOS (Cesarean section: -11.7% days (P < 0.001), hysterectomy: -11.8% days (P = 0.005)), lowered adjusted daily MME consumption from day 0 to day 3 (Cesarean section: -1.6 mg (P < 0.001), hysterectomy: -1.7 mg (P = 0.014)), and reduced risk of ORADEs for Cesarean sections (relative risk of 0.45, P < 0.001). Total pharmacy costs were not significantly different between the two APAP groups.

Conclusions

Post-surgical pain managed with IV APAP in patients undergoing Cesarean section or hysterectomy was associated with shorter LOS, reduced risk of ORADEs, and lower opioid consumption compared to patients managed with oral APAP, without adversely impacting total pharmacy costs.