Treatment objectives

Defining treatment success in depression

Effective anti-depressive therapy means more than improvements in, or even cessation of, clinical symptomatic presentations. To optimise your patients’ chances of achieving true and lasting remission, the full constellation of emotional, physical and cognitive symptoms should be assessed and addressed at diagnosis, throughout treatment and beyond.1 Steps should be taken to prevent relapse wherever possible, and treatment adherence should be encouraged throughout the course of therapy.2,3

Treating the full constellation of symptoms in depression could optimise your patient’s change to achieve full and lasting recovery.1

Achieving remission
A review of the landmark STAR*D study revealed that almost 50% of patients with major depression do not achieve remission following treatment with two different selective serotonin reuptake inhibitors (SSRIs).4

Remission in depression is defined as a return to ‘normalcy’ for the patient, whereby they are fully recovered from all symptoms of the condition.5 In addition, a number of quantifiable definitions of remission exist in line with different assessments of depression severity.6 For example, a score of ≤7 on the Hamilton Depression Rating Scale (HDRS or HAM-D) is occasionally used to define remission in clinical studies, while a score of ≤10 on the Montgomery-Åsberg Depression Rating Scale (MADRS) can also be used.7 However, in clinical practice, patients deemed to be in remission often continue to experience residual depressive symptoms, and treatment up to the point of complete remission is not common practice.3

Treating residual symptoms
Residual cognitive symptoms have been shown to present, on average, for 44% of the time during periods of remission in patients initially diagnosed with depression.3

The presence of residual symptoms following determination of remission, of which cognitive symptoms is among the most prevalent, is often detrimental both to the patient and those around them, as any residual impairment often reduces the patient’s productivity at work and general quality of life.1,3 Over time, this can cause the patient to relapse into another major depressive episode, or even a chronic course of depression.1,3

Residual cognitive symptoms have been shown to be present for up to 44% of the time for patients in remission3

Preventing relapse
In one study of patients considered to be in remission, 76% of those with residual symptoms relapsed within 10 months, compared with 25% of those with no apparent residual symptoms.8

Cessation of the emotional manifestations of depression is not enough to achieve recovery. As residual cognitive symptoms can increase a patient’s risk of relapse, these must also be assessed and addressed appropriately.1,3 One recommended way of ensuring that this is done is to repeatedly evaluate symptom severity at each follow-up appointment, using the same assessments used during the initial diagnostic process.9 This provides a marker of symptom progression and treatment success over time, and may aid the recognition of these residual symptoms, and hence their appropriate treatment.9

Maintaining adherence
In one study, only 30% of patients with depression remained adherent to their treatment after 3 months – almost 50% lower than the rate seen in diabetic and hypertensive patients in the same study.10

Adherence to antidepressant treatment is essential for a successful outcome, and should be maintained for at least six months after symptom cessation.11,12 Yet, in the aforementioned study, while 30% of patients with depression were adherent to their medication three months after treatment initiation, this decreased further to 20% after 6 months, and just 8% after 12 months, highlighting the extent of non-adherence among patients with the condition.13 Such reduced adherence can increase the risk of recurrence and/or relapse in depression, in addition to promoting the persistence of depressive symptoms.14,15 Prolonged depression or relapse also places great burden on healthcare systems as patients seek further care from their treating physician,16 and increases the risk of concomitant medical conditions such as coronary heart disease or diabetes.17,18 Adherence is therefore an important challenge to overcome, and collaborative approaches to patient care such as pharmacist-provided patient education and disease management programs may help those with depression to continue treatment as recommended by their doctor.19,20

References

  1. Greer TL et al. CNS Drugs 2010; 24(4): 267–284.
  2. Akerblad AC et al. Int Clin Psychopharmacol 2006; 21: 117–124.
  3. Conradi HJ et al. Psychol Med 2011; 41: 1165–1174.
  4. Coplan JD et al. Front Behav Neurosci 2014; 8: 189.
  5. Mezzasalma MAU. Diabetol Metab Syndr 2010; 2: 9.
  6. Zimmerman M et al. Am J Psychiatry 2006; 163: 148–150.
  7. Cusin C et al. Rating Scales for Depression. In: Handbook of Clinical Rating Scales and Assessment in Psychiatry and Mental Health. Ed: Baer, Lee, Blais, Mark A. (Eds.), 2010. 
  8. Paykel ES. Dialogues Clin Neurosci 2008; 10(4): 431–437.
  9. Culpepper L. Cognition in MDD: implications for primary care. In: Cognitive dysfunction in Major Depressive Disorder. Ed: McIntyre R, Cha D, 2015.
  10. Culpepper L, 2007 
  11. Bucci KK et al. Am J Health-Syst Pharm 2003; 60: 2601–2605.
  12. The treatment and management of depression in adults, NICE clinical guideline 90. 2009.
  13. National Council on Patient Information and Education (2007).
  14. Doesschate MC et al. J Affect Dis 2009; 115: 167–170.
  15. Melfi CA et al. Arch Gen Psychiatry 1998; 55(12): 1128–1132.
  16. Lin EHB et al. Arch Fam Med 1998; 7: 443–449.
  17. Gan Y et al. BMC psychiatry 2014; 14: 371.
  18. Talbot F and Nouwen A. Diabetes Care 2000; 23: 1556–1562.
  19. Badamgarav E et al. Am J Psychiatry 2003; 160: 2080–2090.
  20. Gilbody S et al. JAMA 2003; 289(23): 3145–3151.