Early detection of suboptimal medication adherence and timely intervention among patients with MDD is a priority for individuals receiving pharmacotherapy[50]. To our knowledge, this is the first study to test the prospective association between childhood trauma, resilience, and medication adherence among persons living with MDD.
The study herein used the MARS self-questionnaire as the adherence measure, focusing on medication behavior, beliefs, and negative side effects of taking medication. A high percentage of the sample (83%) reported having suboptimal medication adherence. Poor adherence to medication in persons with MDD has been widely reported in the literature, ranging from 10.6–85.4%[4]. Our results indicate higher rates of non-adherence in patients with MDD than previously reported by other studies. The causes of the high prevalence rates may be related to the different measurement methods of suboptimal adherence, and it has been stated that self-report questionnaires tend to overestimate adherence behavior[51].
Our study identifies sociodemographic, clinical and psychosocial factors associated with medication adherence through preliminary analysis. We observed that education level, depression severity, anxiety severity, suicidal ideation, suicidal attempt, insomnia symptoms, painful somatic symptoms childhood trauma (including physical abuse, sexual abuse, and physical neglect), and resilience associated with medication adherence. The foregoing results were consistent with other previous findings among psychotropic patients[4, 52]. It can be hypothesized that more vulnerable patients (e.g., individuals who are more severely depressed, anxious, and having more suicidal thoughts, insomnia symptoms, childhood trauma, painful somatic symptoms, and reduced resilience) may be associated suboptimal medication adherence, which could worsen the clinical outcomes, which further promote suboptimal medication adherence[24]. Therefore, early identification of suboptimal adherence should be considered behavioral factors susceptible to influence medication adherence when providing MDD pharmacotherapy.
To date, relatively few studies have examined the association between childhood trauma and suboptimal medication adherence with controlling for the effects of relevant factors among persons with MDD. After adjusting for age, sex, marital status, education level, HAMD-17 scores, GAD-7 scores, suicidal ideation, suicidal attempt, insomnia, SSI pain-related items, our study suggests that childhood trauma, especially sexual abuse, physical neglect, as well as resilience, are closely associated with medication adherence. In contrast, another study argued that emotional abuse was the strongest predictor of suboptimal adherence among patients with MDD[40]. The foregoing differences may be related to the cultural background and traditional education methods of China and western countries.
Childhood trauma may predict medication adherence. Compared with individuals who have not experienced childhood trauma, those with a history of childhood trauma are at greater risk of enduring cognitive and biological vulnerabilities associated with heightened stress sensitivity, which might predispose them to suboptimal adherence[16]. In addition, individuals with childhood trauma may have a poor social support network and trouble building trust with others[53], which can affect medication adherence. This is particularly significant as having a strong support network, the family’s reaction to the disease, and their ability to support and help the patient to pursue the long course of treatment is a critical factor affecting medication adherence[54].
In addition, our study suggested that resilience may play a moderating role in the association of childhood trauma and physical neglect with medication adherence. Moreover, stratification analyses according to the resilience group indicated that both childhood trauma and physical neglect were associated with an increased risk of suboptimal adherence among patients with MDD with low-resilience or medium-resilience. However, the associations between childhood trauma/physical neglect and medication adherence were not found among patients with MDD with high-resilience. The results are reasonable. If people are greater resilience, they are good at recovering from difficulties and stressful situations[55, 56]. When exposed to childhood trauma, persons with MDD have difficulty in altering the stressful situations or planning to solve the problems, which can lead to suboptimal adherence. If people are highly resilient, they tend to use a positive attitude to deal with treatment[57]. Therefore, the adverse effects of childhood trauma on medication adherence may not be further boosted under the condition of higher resilience. Of course, this possibility calls for further examinations.
The present results have significant implications for future research and practice in preventing and managing MDD. Clinicians may consider the routine inquiry about childhood trauma and assessing resilience to add significant prognostic information to their pharmacotherapy. In addition, even though resilience is generally considered to have trait-like characteristics, resilience capacity can be changed[27]. Enhancing resilience is a method that focuses on enhancing strategies to cope with adherence and diminishing the likelihood of non-adherence[58]. Current research suggests that some psychotherapeutic interventions can effectively enhance resilience, especially CBT, which has been shown to be effective in improving resilience[59–61]. Psychiatrists may consider paying attention and giving targeted assistance to improve resilience when providing pharmacotherapy to patients with MDD, especially for individuals with a history of childhood trauma.
Furthermore, childhood years are thought to be a sensitive developmental window for the maturation of emotion regulation[62], interventions aimed at reducing childhood trauma could help prevent the large health and economic burden linked to poor depression course[16], and parents should recognize the adverse effects of childhood trauma on their children and give them more physical or psychological care[63].
Major strengths of this study are its prospective design, longer follow-up was considered in the assessment, the use of objective measures widely used in MDD patients (M.I.N.I., HAMD-17, MARS, CTQ-SF, CD-RISC, etc.), and controlling for the effects of factors associated with medication adherence or childhood trauma during statistical analysis, which has better quality of evidence. However, there are several limitations to this study. First, although most data were measured by self-report, which may lead to biased reporting of childhood trauma experience, resilience, and the adherence behavior can be overestimated, self-reports remain a common and accepted method. In this regard, further studies should combine self-reports with more objective indirect measurements of adherence, such as pill counts and prescription refills[64, 65]. Second, a high percentage of the sample (66.3%) is female because of the significantly higher prevalence of MDD in females than males[66].