Predicting Participation in Psychiatric Randomized Controlled Trials: Insights From the STEP-BD

Medicaid Expansion of the Patient Protection and Affordable Care Act and Participation of Patients With Medicaid in Cancer Clinical Trials

Importance

The Patient Protection and Affordable Care Act (ACA) Medicaid expansion resulted in increased use of Medicaid insurance nationwide. However, the association between Medicaid expansion and access to clinical trials has not been examined to date.

Objective

To examine whether the implementation of ACA Medicaid expansion was associated with increased participation of patients with Medicaid insurance in cancer clinical trials.

Design, Setting, and Participants

Data for this cohort study of 51 751 patients were from the SWOG Cancer Research Network. All patients aged 18 to 64 years and enrolled in treatment trials with Medicaid or private insurance between April 1, 1992, and February 29, 2020, were included. Interrupted time-series analysis with segmented logistic regression was used. The monthly unemployment rate and presidential administration were adjusted to reflect potential differences in Medicaid use associated with economic conditions and national administrative policies, respectively. Data analysis was conducted between June 22, 2021, and August 5, 2022.

Exposure

Implementation of Medicaid expansion on January 1, 2014, was the independent exposure variable.

Main Outcomes and Measures

The number and proportion of patients by insurance type enrolled in cancer clinical trials over time were analyzed.

Results

Overall, data for 51 751 patients were analyzed. Mean (SD) age was 50.6 (9.8) years, 67.3% of patients were female, 41.1% were younger than 50 years, and 9.1% used Medicaid. A 19% annual increase (odds ratio [OR], 1.19; 95% CI, 1.11-1.28; P < .001) was identified in the odds of patients using Medicaid after the ACA Medicaid expansion, resulting in a 52% increase (OR, 1.52; 95% CI, 1.29-1.78; P < .001) compared with what was expected in the number of Medicaid patients enrolled over time. The association was greater in states that adopted Medicaid expansion in 2014 to 2015 (OR, 1.26; 95% CI, 1.15-1.38; P < .001) compared with other states (OR, 1.08; 95% CI, 0.96-1.21; P = .20; P = .04 for interaction). By February 2020, the proportion of patients with Medicaid insurance was 17.8% (95% CI, 15.0%-20.8%; P < .001), whereas the expected proportion had ACA Medicaid expansion not occurred was 6.9% (95% CI, 4.4%-10.3%; P < .001).

Conclusions and Relevance

Findings suggest that implementation of ACA Medicaid expansion was associated with increased participation of patients using Medicaid in cancer clinical trials. Improved participation in clinical trials for Medicaid-insured patients is critical for socioeconomically vulnerable patients seeking access to the newest treatments available in trials and for improving confidence that trial findings apply to patients of all backgrounds.

Placebo Effect in Obsessive-Compulsive Disorder (OCD). Placebo Response and Placebo Responders in OCD: The Trend Over Time

BACKGROUND

Placebo response appears to be increasing in antidepressant, antipsychotic and various internal medicine trials. A similar trend has been reported for OCD during 1989-1999. Placebo response is generally considered as the extent to which placebo treatment is associated with core symptom improvement. In this analysis, we used Joinpoint regression to assess the time trend of both placebo response and placebo responder rates according to the year of publication with no time restriction in OCD drug trials.

METHODS

We included drug and/or psychotherapy trials vs. placebo from PubMed, Embase, CINAHL, and PsycINFO retrieved through the search (placebo OR sham) AND (obsessive* OR OCD). We included studies through investigator consensus. We then performed on data of included studies log-linear joinpoint segmented regression models using a p<0.05 cutoff.

RESULTS

We included 113 studies from 112 published papers. Placebo mean annual response rates in OCD studies significantly increased from 1991 to 2017 with an annual percent change (APC) of 0.66%, while placebo mean annual responder rates also significantly increased from 2010 to 2017, with an APC of 5.45%. Drug mean annual response rates in OCD studies significantly increased from 1987 to 2012 with an APC of 0.72%, while the corresponding responder rates did not show statistically significant APC changes between 1984 and 2017.

CONCLUSION

We observed a tendency for placebo to increase both measures of response in OCD clinical drug trials through the years that tend to approximate the responses shown by drugs. Changes in the type of study (moving from classical head to head comparisons to add-on studies in treatmentresistant populations) and countries involved in experimentation may partially account for some portion of these results. It appears that placebo effects are becoming more elusive and out of control.