Medicaid Expansion Under the Affordable Care Act: Potential Changes in Receipt of Mental Health Treatment Among Low-Income Nonelderly Adults With Serious Mental Illness.

OBJECTIVES: We designed this study to examine differences in receipt of mental health treatment between low-income uninsured nonelderly adults with serious mental illness (SMI) who were eligible for Medicaid under the Affordable Care Act (ACA) and their existing Medicaid counterparts. Assessing these differences might estimate the impact of the Medicaid expansion efforts under the ACA on receipt of mental health treatment among uninsured nonelderly adults with SMI. METHODS: We examined data from 2000 persons aged 18 to 64 years who participated in the 2008 to 2013 National Survey on Drug Use and Health, had income below 138% of the federal poverty level, met SMI criteria, and either were uninsured (n = 1000) or had Medicaid-only coverage (n = 1000). We defined SMI according to the Alcohol, Drug Abuse, and Mental Health Administration Reorganization Act. We used descriptive analyses and logistic regression modeling. RESULTS: In the 28 states currently expanding Medicaid, the model-adjusted prevalence (MAP) of receiving mental health treatment among Medicaid-only enrollees with SMI (MAP = 71.3%; 95% confidence interval [CI] = 65.74%, 76.29%) was 30.1% greater than their uninsured counterparts (MAP = 54.8%; 95% CI = 48.16%, 61.33%). In the United States, the MAP of receiving mental health treatment among Medicaid-only enrollees with SMI (MAP = 70.4%; 95% CI = 65.67%, 74.70%) was 35.9% higher than their uninsured counterparts (MAP = 51.8%; 95% CI = 46.98%, 56.65%). CONCLUSIONS: Estimated increases in receipt of mental health treatment because of enrolling in Medicaid among low-income uninsured adults with SMI might help inform planning and implementation efforts for the Medicaid expansion under the ACA.

Mental health treatment access and quality in the army: survey of mental health clinicians.

OBJECTIVE: The goal of this study was to identify factors affecting timely, quality mental health and substance abuse treatment for service members and characterize patients at the greatest risk of having problems accessing treatment. METHODS: An electronic survey was emailed to 2,310 Army mental healthcare providers. After providers with undeliverable emails and who self-reported not being behavioral health providers were excluded, 543 (26%) of the remaining 2,104 providers responded. This represented approximately a quarter of all Army behavioral health providers at the time of the survey. Of these 543 providers, 399 (73%) reported treating at least one service member during their last typical work week and provided clinically detailed data on one systematically selected service member. RESULTS: The majority of the clinicians reported being able to spend sufficient time with patients (91.8%) and schedule encounters to meet patients' needs (82.4%). The clinicians also identified services where treatment access was more limited and patient subgroups with an unmet need for additional clinical care or services. Specifically, a significant proportion of clinicians reported that they were "never, rarely, or sometimes" able to provide or arrange for mental health treatment for the sampled service member's children (52.0%), provide or arrange for marriage and family therapy (40.1%), coordinate care effectively with primary care (36.7%), provide or arrange for care/case management (28.3%), or provide or arrange for substance abuse treatment (24.9%). Patients with more severe symptoms and diagnostic and clinical complexity had higher rates of problems with treatment access. CONCLUSIONS: Our findings highlight opportunities to improve access to timely, quality treatment for service members and their families.

Testing DSM-5 in routine clinical practice settings: feasibility and clinical utility.

OBJECTIVE: This article describes the clinical utility and feasibility of proposed DSM-5 criteria and measures as tested in the DSM-5 Field Trials in Routine Clinical Practice Settings (RCP). METHODS RCP data were collected online for six months (October 2011 to March 2012). Participants included psychiatrists, licensed clinical psychologists, clinical social workers, advanced practice psychiatric-mental health nurses, licensed counselors, and licensed marriage and family therapists. Clinicians received staged, online training and enrolled at least one patient. Patients completed self-assessments of cross-cutting symptom domains, disability measures, and an evaluation of these measures. Clinicians conducted diagnostic interviews and completed DSM-5 and related assessments and a clinical utility questionnaire. RESULTS: A total of 621 clinicians provided data for 1,269 patients. Large proportions of clinicians reported that the DSM-5 approach was generally very or extremely easy for assessment of both pediatric (51%) and adult (46%) patients and very or extremely useful in routine clinical practice for pediatric (48%) and adult (46%) patients. Clinicians considered the DSM-5 approach to be better (57%) or much better (18%) than that of DSM-IV. Patients, including children age 11 to 17 (47%), parents of children age six to ten (64%), parents of adolescents age 11 to 17 (72%), and adult patients (52%), reported that the cross-cutting measures would help their clinicians better understand their symptoms. Similar patterns in evaluations of feasibility and clinical utility were observed among clinicians from various disciplines. CONCLUSIONS: The DSM-5 approach was feasible and clinically useful in a wide range of routine practice settings and favorably received by both clinicians and patients.

Social integration and suicide-related ideation from a social network perspective: a longitudinal study among inner-city African Americans.

Social network density, as measured by the extent to which network members know each other, was examined to determine whether it is associated with suicide-related ideation and plan approximately 3 years later. Eight hundred and nineteen African Americans were interviewed at Wave 1 (1997-1999) and Wave 4 (2001-2003) of the Self-Help In Eliminating Life-Threatening Diseases (SHIELD) study, a HIV preventive intervention study in Baltimore, MD. Multinomial logistic regression models were used to compare risks of suicide-related ideation and plan at Wave 4 by Wave 1 density. Even after adjusting for baseline sociodemographic characteristics and depressive symptoms, individuals with a lower level of density were three times more likely to report suicide-related ideation and plan in the past year at Wave 4. The findings reinforce the importance of social integration among inner-city African Americans from a social network perspective. Future research should examine the mechanisms associated with this relationship and other social network constructs.

An introduction to sensitivity analysis for unobserved confounding in nonexperimental prevention research.

Despite the fact that randomization is the gold standard for estimating causal relationships, many questions in prevention science are often left to be answered through nonexperimental studies because randomization is either infeasible or unethical. While methods such as propensity score matching can adjust for observed confounding, unobserved confounding is the Achilles heel of most nonexperimental studies. This paper describes and illustrates seven sensitivity analysis techniques that assess the sensitivity of study results to an unobserved confounder. These methods were categorized into two groups to reflect differences in their conceptualization of sensitivity analysis, as well as their targets of interest. As a motivating example, we examine the sensitivity of the association between maternal suicide and offspring's risk for suicide attempt hospitalization. While inferences differed slightly depending on the type of sensitivity analysis conducted, overall, the association between maternal suicide and offspring's hospitalization for suicide attempt was found to be relatively robust to an unobserved confounder. The ease of implementation and the insight these analyses provide underscores sensitivity analysis techniques as an important tool for nonexperimental studies. The implementation of sensitivity analysis can help increase confidence in results from nonexperimental studies and better inform prevention researchers and policy makers regarding potential intervention targets.

DSM-5 field trials in the United States and Canada, Part II: test-retest reliability of selected categorical diagnoses.

OBJECTIVE: The DSM-5 Field Trials were designed to obtain precise (standard error,0.1) estimates of the intraclass kappa asa measure of the degree to which two clinicians could independently agree on the presence or absence of selected DSM-5 diagnoses when the same patient was interviewed on separate occasions, in clinical settings, and evaluated with usual clinical interview methods. METHOD: Eleven academic centers in the United States and Canada were selected,and each was assigned several target diagnoses frequently treated in that setting.Consecutive patients visiting a site during the study were screened and stratified on the basis of DSM-IV diagnoses or symptomatic presentations. Patients were randomly assigned to two clinicians for a diagnostic interview; clinicians were blind to any previous diagnosis. All data were entered directly via an Internet-based software system to a secure central server. Detailed research design and statistical methods are presented in an accompanying article. RESULTS: There were a total of 15 adult and eight child/adolescent diagnoses for which adequate sample sizes were obtained to report adequately precise estimates of the intraclass kappa. Overall, five diagnoses were in the very good range(kappa=0.60­0.79), nine in the good range(kappa=0.40­0.59), six in the questionable range (kappa = 0.20­0.39), and three in the unacceptable range (kappa values,0.20). Eight diagnoses had insufficient sample sizes to generate precise kappa estimates at any site. CONCLUSIONS: Most diagnoses adequately tested had good to very good reliability with these representative clinical populations assessed with usual clinical interview methods. Some diagnoses that were revised to encompass a broader spectrum of symptom expression or had a more dimensional approach tested in the good to very good range.

DSM-5 field trials in the United States and Canada, Part III: development and reliability testing of a cross-cutting symptom assessment for DSM-5.

OBJECTIVE: The authors sought to document, in adult and pediatric patient populations, the development, descriptive statistics,and test-retest reliability of cross-cutting symptom measures proposed for inclusion in DSM-5. METHOD: Data were collected as part of the multisite DSM-5 Field Trials in large academic settings. There were seven sites focusing on adult patients and four sites focusing on child and adolescent patients.Cross-cutting symptom measures were self-completed by the patient or an informant before the test and the retest interviews, which were conducted from 4 hours to 2 weeks apart. Clinician-report measures were completed during or after the clinical diagnostic interviews. Informants included adult patients, child patients age 11 and older, parents of all child patients age 6 and older, and legal guardians for adult patients unable to self-complete the measures. Study patients were sampled in a stratified design,and sampling weights were used in data analyses. The mean scores and standard deviations were computed and pooled across adult and child sites. Reliabilities were reported as pooled intraclass correlation coefficients (ICCs) with 95% confidence intervals. RESULTS: In adults, test-retest reliabilities of the cross-cutting symptom items generally were good to excellent. At the child and adolescent sites, parents were also reliablereporters of their children's symptoms,with few exceptions. Reliabilities were not as uniformly good for child respondents, and ICCs for several items fell into the questionable range in this age group. Clinicians rated psychosis with good reliability in adult patients but were less reliable in assessing clinical domains related to psychosis in children and to suicide in all age groups. CONCLUSIONS: These results show promising test-retest reliability results for this group of assessments, many of which are newly developed or have not been previously tested in psychiatric populations

DSM-5 field trials in the United States and Canada, Part I: study design, sampling strategy, implementation, and analytic approaches.

OBJECTIVE: This article discusses the design,sampling strategy, implementation,and data analytic processes of the DSM-5 Field Trials. METHOD: The DSM-5 Field Trials were conducted by using a test-retest reliability design with a stratified sampling approach across six adult and four pediatric sites in the United States and one adult site in Canada. A stratified random sampling approach was used to enhance precision in the estimation of the reliability coefficients. A web-based research electronic data capture system was used for simultaneous data collection from patients and clinicians across sites and for centralized data management.Weighted descriptive analyses, intraclass kappa and intraclass correlation coefficients for stratified samples, and receiver operating curves were computed. The DSM-5 Field Trials capitalized on advances since DSM-III and DSM-IV in statistical measures of reliability (i.e., intraclass kappa for stratified samples) and other recently developed measures to determine confidence intervals around kappa estimates. RESULTS: Diagnostic interviews using DSM-5 criteria were conducted by 279 clinicians of varied disciplines who received training comparable to what would be available to any clinician after publication of DSM-5.Overall, 2,246 patients with various diagnoses and levels of comorbidity were enrolled,of which over 86% were seen for two diagnostic interviews. A range of reliability coefficients were observed for the categorical diagnoses and dimensional measures. CONCLUSIONS: Multisite field trials and training comparable to what would be available to any clinician after publication of DSM-5 provided "real-world" testing of DSM-5 proposed diagnoses.

Time to hospitalization for suicide attempt by the timing of parental suicide during offspring early development.

CONTEXT Previous studies have suggested that children who experience parental suicide at earlier ages are at higher risk of future hospitalization for suicide attempt. However, how the trajectories of risk differ by offspring age at the time of parental suicide is currently unknown. OBJECTIVE To study time at risk to suicide attempt hospitalization among offspring of suicide decedents as compared with offspring of unintentional injury decedents by their developmental period at the time of parental death. DESIGN Population-based retrospective cohort study. SETTING Sweden. PARTICIPANTS Twenty-six thousand ninety-six offspring who experienced parental suicide and 32 395 offspring of unintentional injury decedents prior to age 25 years between the years 1973 and 2003. MAIN OUTCOME MEASURE Parametric survival analysis was used to model the time to hospitalization for suicide attempt among offspring who lost a parent during early childhood (0-5 years old), later childhood (6-12 years old), adolescence (13-17 years old), and young adulthood (18-24 years old). RESULTS The risk in offspring who lost a parent to suicide or an unintentional injury during childhood surpassed the other age groups' risk approximately 5 years after the origin and, for the youngest group, continued to rise over decades. Offspring who lost a parent during adolescence or young adulthood were at greatest risk within 1 to 2 years after parental death, and risk declined over time. Offspring who lost a parent to suicide in childhood and young adulthood had earlier onset of hospitalization for suicide attempt compared with offspring who lost a parent to an unintentional injury. CONCLUSIONS The hospitalization risk for suicide attempt in offspring who lost a parent during their childhood is different from those who lost a parent later in development. The results suggest critical windows for careful monitoring and intervention for suicide attempt risk, especially 1 to 2 years after parental death for the older age groups and over decades for childhood survivors of parental death.

The interaction of parental history of suicidal behavior and exposure to adoptive parents' psychiatric disorders on adoptee suicide attempt hospitalizations.

OBJECTIVE: The authors examined the risk of suicide attempt or other psychiatric hospitalization among adoptees whose biological parents died from or were hospitalized for suicidal behavior (BPSB) relative to adoptees whose biological parents had a psychiatric hospitalization but never for suicide attempt (BPPH). The authors examined whether risk was moderated by having an adoptive parent who had a psychiatric hospitalization during the adoptee's childhood or adolescence. METHOD: This retrospective cohort study used national longitudinal population-based Swedish registry data from 1973 to 2003 to identify 2,516 adoptees with BPSB and 5,875 adoptees with BPPH. Cox regression models compared the risk for suicide attempt and other psychiatric hospitalization in the two groups. RESULTS: The interaction of BPSB with adoptive mothers' psychiatric hospitalization while the adoptee was younger than 18 years old increased the risk for an adoptee's suicide attempt. Neither BPSB nor psychiatric hospitalization among adoptive mothers alone placed adoptees at greater risk for suicide attempt hospitalizations. The interaction results were specific to adoptee suicide attempt. CONCLUSIONS: Exposure to the hospitalization of an adoptive mother because of a psychiatric disorder amplified an adoptee's risk for suicide attempt hospitalization among those adoptees at high genetic risk of suicide or suicide attempt. These results imply that suicide attempts among those at biological risk might be prevented with the early recognition and care of parental psychiatric illness.

Suicidal ideation and suicide attempt across stages of nonmedical prescription opioid use and presence of prescription opioid disorders among U.S. adults.

OBJECTIVE: This study compares the likelihood of suicidal ideation and suicide attempt across stages of nonmedical prescription opioid use and by presence of prescription opioid disorders (dependence and/or abuse) among adult respondents. METHOD: In the 2009 National Survey on Drug Use and Health, 37,933 adult respondents were asked if they had thought about suicide or had attempted suicide in the past year. The likelihood of ideation and attempt were compared across the following four categories: (a) those who never used prescription opioids, (b) former users, (c) persistent users, and (d) recent-onset users. Weighted multinomial logistic regressions were used to examine if these stages and presence of Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition, criteria for prescription opioid disorders were associated with suicidal ideation and suicide attempt. RESULTS: Five percent of respondents (n = 2,021) reported suicidal ideation; of these, 15% (n = 310) reported attempt. Former and persistent nonmedical prescription opioid users had greater odds of suicidal ideation than those who never used these medications nonmedically. The stages of prescription opioid use were not associated with suicide attempt. Presence of prescription opioid disorders among past-year prescription opioid users was associated with suicidal ideation but not suicide attempt. CONCLUSIONS: The risk for suicidal ideation was greater in those who no longer used prescription opioids, in persistent users, and among nonmedical users who had a prescription opioid disorder compared with users without the disorder. The results suggest a need to continue monitoring for suicide risk even among those who have stopped using prescription opioids.

Understanding subtypes of inner-city drug users with a latent class approach.

AIMS: We empirically identified subtypes of inner-city users of heroin and cocaine based on type of drug used and route of administration. METHOD: The sample was recruited from the communities in Baltimore, MD (SHIELD study) and consisted of 1061 participants who used heroin and or cocaine in the past 6 months on a weekly basis or more. Latent class analysis (LCA) was used to identify subtypes of drug users based on type of drug and route of administration. Logistic regression was used to compare the subtypes on depressive symptoms, injection risk and drug network compositions. FINDINGS: Inner-city drug users were classified into five subtypes: three subtypes of injection drug users (IDUs) [heroin injecting (n=134; 13%), polydrug and polyroute (n=88, 8%), and heroin and cocaine injecting (n=404, 38%)], and two subtypes with low proportions of IDUs (LIDUs) [heroin snorting (n=275, 26%) and crack smoking (n=160; 14%)]. The polydrug and polyroute subtype had the highest depressive symptoms risk among all subtypes. Injection risk was lowest in the heroin injecting subtype and significantly differed from heroin and cocaine injecting subtype. The IDU subtypes also varied in the drug network compositions. The LIDU subtypes had similar depressive symptoms risk but vastly differed in the drug network compositions. CONCLUSIONS: Subgroups of inner-city cocaine and heroin users based on type and route of administration differed in their depressive symptoms, injection risk and drug network compositions. Future studies should longitudinally examine factors associated with transitioning across these subtypes to better inform prevention and treatment efforts.

Past year treatment status and alcohol abuse symptoms among US adults with alcohol dependence.

OBJECTIVE: We tested whether the number and type of alcohol abuse symptoms were associated with an increased likelihood of treatment seeking among respondents with alcohol dependence. METHODS: Data from 4027 adult respondents from 2006 and 2007 National Survey on Drug Use and Health (NSDUH) who met DSM-IV criteria for the past year alcohol dependence were used. Respondents were classified according to the number of past year alcohol abuse symptoms endorsed, as well as type of abuse symptom. Associations were estimated using weighted multivariate logistic regressions that controlled for severity of alcohol dependence, other drug use disorders and other characteristics. RESULTS: Twenty-eight percent of individuals with alcohol dependence had one alcohol abuse symptom, 20% had two and 19% had three or four. Individuals with more alcohol abuse symptoms differed from those without alcohol abuse symptoms in a number of sociodemographic characteristics and severity of alcohol and drug dependence. Even after adjusting for these factors, individuals with three or four alcohol abuse symptoms had 2.67 times increased odds of treatment seeking, as compared to those without alcohol abuse symptoms [95% CI=1.65-4.30]. However, individuals with one or two alcohol abuse symptoms were no more likely to seek treatment than those without alcohol abuse symptoms. Majority of those with one or two alcohol abuse symptoms endorsed the hazardous abuse symptom. CONCLUSION: Alcohol abuse symptoms are important factors for treatment seeking in individuals with alcohol dependence, but only among certain subset of individuals with three or four alcohol abuse symptoms. Examining structural and psychosocial differences across these subgroups may help inform and reduce barriers to treatment seeking among this population.

Maternal or paternal suicide and offspring's psychiatric and suicide-attempt hospitalization risk.

OBJECTIVE: We examined whether the risk for psychiatric morbidity requiring inpatient care was higher for offspring who experienced parental suicide, compared with offspring of fatal accident decedents, and whether the association varied according to the deceased parent's gender. METHODS: Children and adolescents (0-17 years of age) who experienced maternal (N = 5600) or paternal (N = 17,847) suicide in 1973-2003 in Sweden were identified by using national, longitudinal, population-based registries. Cox regression modeling was used to compare psychiatric hospitalization risks among offspring of suicide decedents and propensity score-matched offspring of accident decedents. RESULTS: Offspring of maternal suicide decedents had increased risk of suicide-attempt hospitalization, after controlling for psychiatric hospitalization for decedents and surviving parents, compared with offspring of maternal accidental decedents. Offspring of paternal suicide decedents had similar risk of suicide-attempt hospitalization, compared with offspring of accident decedents, but had increased risk of hospitalization attributable to depressive and anxiety disorders. The magnitude of risks for offspring suicide-attempt hospitalization was greater for those who experienced maternal versus paternal suicide, compared with their respective control offspring (interaction P = .05; offspring of maternal decedents, adjusted hazard ratio: 1.80 [95% confidence interval: 1.19-2.74]; offspring of paternal decedents, adjusted hazard ratio: 1.14 [95% confidence interval: 0.96-1.35]). CONCLUSIONS: Maternal suicide is associated with increased risk of suicide-attempt hospitalization for offspring, beyond the risk associated with maternal accidental death. However, paternal suicide is not associated with suicide-attempt hospitalization. Future studies should examine factors that might differ between offspring who experience maternal versus paternal suicide, including genetic or early environmental determinants.

Patterns of alcohol-dependence symptoms using a latent empirical approach: associations with treatment usage and other correlates.

OBJECTIVE: The aim of this study was to understand the variation in response to alcohol use by identifying classes of alcohol users based on alcohol-dependence symptoms and to compare these classes across demographic characteristics, abuse symptoms, and treatment usage. METHOD: Data from combined 2002-2005 National Survey on Drug Use and Health identified 110,742 past-year alcohol users, age 18 years or older. Latent class analysis defined classes based on observed clustering of alcohol-dependence symptoms based on criteria from the Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition (DSM-IV). Chi-square statistics were used to test differences in sociodemographic and alcohol-abuse characteristics across classes. Multivariable latent class regressions were used to compare treatment usage across classes. RESULTS: The four-class model had the best overall fit and identified classes that differed quantitatively and qualitatively, with 2.3% of the users in the most-severe class and 83.8% in the least-severe/ not-affected class. These classes differed in a number of demographic characteristics and alcohol-abuse symptoms. All individuals in the most severe class met DSM-IV criteria for alcohol dependence; 80% of this class had alcohol-abuse symptoms. Twenty-six percent of the moderate and 50% of the moderate-high class met dependence criteria. Approximately 19% of the most-severe class and less than 5% of the moderate and moderate-high class received treatment for alcohol in the past year. CONCLUSIONS: This study demonstrates that meeting dependence criteria only partially captures variations in responses to severity of alcohol problems. Although individuals in the most-severe class were more likely to perceive need and receive treatment, the percentage of individuals receiving treatment was low.

Social norms, social networks, and HIV risk behavior among injection drug users.

Social network structure and norms are linked to HIV risk behavior. However little is known about the gradient of norm of HIV risk that exists among social networks. We examined the association between injection risk network structure and HIV risk norms among 818 injection drug users (IDUs). IDUs were categorized into four distinct groups based on their risk behaviors with their drug networks: no network members with whom they shared cookers or needles, only cooker-sharing member, one needle-sharing member, and multiple needle-sharing members. The riskiest group, networks of multiple needle sharers, was more likely to endorse both risky needle-sharing and sex norms. Networks of only cooker sharers were less likely to endorse high-risk norms, as compared to the networks with no sharing. There were also differences based on gender. Future HIV prevention interventions for IDUs should target both injection and sex risk norms, particularly among IDUs in the multiple needle-sharing networks.

The impact of parental suicide on child and adolescent offspring.

Child and adolescent survivors of parental suicide experience two stressful events simultaneously: (1) the loss of a primary caregiver, and (2) suicidal death of a significant person. These youths are thought to be at increased risk for mental health problems, but a systematic review of studies on these survivors has not yet been conducted. A comprehensive search for published literature identified nine studies. The existent studies provided modest yet inconsistent evidence on the impact of parental suicide on offspring psychiatric and psychosocial outcomes. More methodologically rigorous research is needed to inform and guide postvention efforts for these survivors.

Social networks, norms, and 12-step group participation.

In a sample of active drug users, we assessed the associations between frequency of attending a 12-step program, perceived social norms, and social network structure. Participants who reported that most or all of their drug partners attended 12-step groups were over ten times more likely to be frequent attenders compared to individuals who did not go to Narcotics Anonymous (NA). While social network structure of number of cocaine and heroin users and number of members in treatment was associated with frequent attendance, there was no association among individuals who infrequently went to a 12-step program. Individuals who are trying to control their drug use should be encouraged to affiliate with others in recovery or attending a 12-step program.

Three-dimensional splay fault geometry and implications for tsunami generation.

Megasplay faults, very long thrust faults that rise from the subduction plate boundary megathrust and intersect the sea floor at the landward edge of the accretionary prism, are thought to play a role in tsunami genesis. We imaged a megasplay thrust system along the Nankai Trough in three dimensions, which allowed us to map the splay fault geometry and its lateral continuity. The megasplay is continuous from the main plate interface fault upwards to the sea floor, where it cuts older thrust slices of the frontal accretionary prism. The thrust geometry and evidence of large-scale slumping of surficial sediments show that the fault is active and that the activity has evolved toward the landward direction with time, contrary to the usual seaward progression of accretionary thrusts. The megasplay fault has progressively steepened, substantially increasing the potential for vertical uplift of the sea floor with slip. We conclude that slip on the megasplay fault most likely contributed to generating devastating historic tsunamis, such as the 1944 moment magnitude 8.1 Tonankai event, and it is this geometry that makes this margin and others like it particularly prone to tsunami genesis.