Innovations In Clinical Neuroscience

SEP-OCT 2014

A peer-reviewed, evidence-based journal for clinicians in the field of neuroscience

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Page 56 of 201

[ V O L U M E 1 1 , N U M B E R 9 – 1 0 , S E P T E M B E R – O C T O B E R 2 0 1 4 ] Innovations in CLINICAL NEUROSCIENCE 57 divides active suicidal ideation into four categories: 1) "Active suicidal ideation: nonspecific (no method, intent, or plan)," 2) "Active suicidal i deation: method, but no intent or plan," 3) "Active suicidal ideation: method and intent, but no plan," and 4) "Active suicidal ideation: method, intent, and plan." 4 The four acknowledged categories are anchored in the presence or absence of a method, intent, or a plan. These four categories, however, do not represent all of the possible combinations of method, intent, or plan. As shown in Table 1, there are a total of 16 possible combinations of the active ideation domains of method, intent, and plan (2 response options to the power of 4 domains=16) and a total of 32 possible combinations when passive ideation is also used as a factor (2 response options to the power of 4 domains=16 multiplied by 2 types of ideation: active and passive). The FDA framework, however, is limited to five of these 16 combinations for active ideation (i.e., the 4 identified combinations plus the null of the 4 [combination number 1]) and six of the 32 combinations for active and passive ideation combined. Table 1 illustrates the combinations captured and not captured based on category titles, while Table 2 illustrates the combinations captured and not captured based on category definitions. Regrettably, reducing active ideation to four categories leaves no room for patients who have events that fall into other categories that are not specified. More importantly, limiting the number to four gives a false sense of safety, communicating that there is not a problem where there could well be one (type II error) and making it seem as if other categories do not exist or do not matter. Consider the patient who has active suicidal ideation with no method or intent but does have a plan or the patient with active suicidal ideation, intent, and a plan but no method. There are as many as 11 other potential combinations of active suicidal ideation. Unfortunately these assumptions can lead to a situation where a significant proportion of suicidal ideation is s imply not captured. The following two examples illustrate these issues: Example 1: Single case report. One suicidal person presented detailed records of suicidal ideation she kept over a nine-month period. Instead of aggregating suicidality phenomena into specific combinations over a specific timeframe (e.g., a week or since the last visit), as is now usually done in suicide assessment scales, the subject classified each event individually into its exact combination category. 11 The results (Figures 1 and 2) indicate that although the FDA-CASA 2012 categories captured almost 80 percent of the suicidal ideation events the subject experienced, the 20 percent of events not captured (Figure 1) constituted almost 60 percent of the total time she experienced suicidality (Figure 2). As shown in Figure 2, the FDA-CASA 2012 categories captured suicidal phenomena that accounted for 40.3 percent of the time spent (28.5% ideation combinations + 11.8% behaviors). This left a residual 59.7 percent of the time spent during which she experienced suicidal phenomena not captured by the FDA categories. To put this in a numeric perspective, the FDA-CASA 2012, applied as written, did not capture 4,256 of the 21,210 suicidality events this person experienced because these events fell outside the combinations allowed. More importantly, the FDA-CASA 2012 did not capture almost 17,785 minutes (296 hours, 25 minutes) of the 29,804 minutes of the suicidal ideation she suffered over the nine- month time frame. 11 This example, while it needs to be replicated, is a valuable one since it is the first time, to our knowledge, that every single suicidality event was individually classified into its exact combination category over such an extended period of time. Example 2: Validation study dataset. The Sheehan-Suicidality Tracking Scale (S-STS)/InterSePT Scale for Suicidal Thinking-Plus ( ISST-Plus)/C–SSRS validation study 1 2 provided a unique opportunity to further examine the extent of missing combinations in the FDA-CASA 2012. This study tested the agreement of two test instruments (S-STS and ISST-Plus) with the C–SSRS (treated as the gold standard). The three scales were administered in a random order sequence by independent, blinded raters. The results showed that the C–SSRS and the FDA-CASA 2012 categories did not capture combinations of suicidal ideation, method, intent, and plan that were detected in 67 percent of the subjects using the clinician-rated S-STS, 80 percent of the subjects using the patient-rated S-STS, and 76 percent of the subjects using the ISST-Plus. These results are undoubtedly a function of the fact that the S-STS and the ISST-Plus were both designed to capture all 32 combinations, as shown in Table 1, while C–SSRS and the FDA-CASA 2012 are confined to a much more limited number of combinations. Problematic assumptions. Part of the problem seems to be that the FDA 2012 Draft Guidance appears to make several problematic assumptions. First, an assumption is made that passive ideation precludes method, intent, and plan. This is problematic since a suicidal subject can experience hallucinations, nightmares, and even daydreams in which method and plan are powerful features. Patients may even respond to command hallucinations with suicide attempts. Second, an assumption is made that suicidal ideation generally reflects a staircase of escalating severity in which patients move up through the steps of suicidal ideation, abandoning passive ideation, for example, for active ideation and adopting more features (method, intent, plan) as the severity of their ideation increases. This is problematic for two reasons: 1) We

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