**6. Issues and controversies**

#### **6.1 Does age matter?**

Reflecting the heterogeneity and etiological complexity of mental health in old age [48], a broad range of measures and a multimethod approach was selected in the presented studies. About late adulthood and young-old age, several questions were addressed. To begin with: Would advancing age matter in terms of treatment response? Meta-analytic findings on NET [29] did not support this hypothesis. Furthermore, in a recent study including 2578 adults – aged from 18 to 80 years [49], the single factor limiting treatment response in all outcomes was found to be the number of traumatic events, confirming the established dose-response correlation of higher trauma exposure and elevated PTSD symptom severity [2, 50]. Taken together, advancing age does not matter in terms of treatment response. In terms of etiological complexity and of biographical and historical context, however, age is highly influential, requiring historical sensitivity and detailed curiosity from therapists.

#### **6.2 Past or present?**

Like all exposure-based treatments, NET addresses the way patients cognitively cope with past events. The treatment strategies of NET have been described as reorganizing memories and restoring narrative continuity and coherence [27]. In the RCT comparing NET and PCT, present-centred therapy (PCT) served as an active comparator. PCT focuses on the present: coping with concurrent stressors, maladaptive interaction patterns and learning solution-focused techniques [9]. In addition to this contrast, there are similarities as well. Both 'dealing with the past' and 'coping with present stressors' refer to (cognitive and emotional) coping with either distressing memories and meanings or maladaptive behavior patterns. Similar considerations might be valid regarding other comparisons, such as Prolonged Exposure versus Relaxation training [51]. The conclusion might be that engaging in such a process in a therapeutic relationship allows for changing both kinds of coping. Patient-reported outcomes suggested a gradual shift in cognitions and emotions, not quite resulting in the complete extinction of old feelings, but expanding the patients' experiential repertory.

Since treatment changes in NET and PCT are found to be more similar than assumed, their direct comparison calls for close attention. The results of the RCT show that both approaches are safe and effective. Unexpectedly, at follow-up, NET and PCT

show equal efficacy. Apparently, in this population dealing with the past and coping with the present show equal importance. Remarkably, change in terms of PTSD symptoms took place at a different pace per intervention. The gradual symptom decrease in the NET-group can be understood as an effect of the taxing exposure in NET. In contrast to the response pattern of PCT, the symptom decline in NET continued after treatment. This difference might be related to different learning strategies in both interventions. It could be suggested that increased coherence and habituation are more internalizing processes than problem-solving techniques, leading to more sustainable treatment results. The continuous symptom decrease in the NET-group tantalizingly suggests a further decline beyond the follow-up interval used and calls for a replication of the comparison with a longer follow-up interval. Meta-analytic findings regarding persisting within-treatment effects in NET justify such suggestions [29].
