K. Suria Prabha^1*, G. P. Mohanta², R. Manavalan² and P. Muthu Prasanna³

¹Department of Pharmaceutics ,C.L.Baid Mehta College of Pharmacy, Chennai (India).

²Department of Pharmacy, Annamalai University, Tamilnadu (India).

³Department of Pharmaceutics , Hindu college of Pharmacy, Guntur (India).

Abstract

To investigate the prevailing prescribing practices in the treatment of depression and to determine whether these practices reflects research findings. Patient profiles were reviewed retrospectively between February 2006 to January 2007 in private hospital at Chennai. The total study population includes 750 patient. According to this study , SSRIs agent are favored as first line treatment in a first episode of depression and are prescribed more frequently because the side effects are better tolerated than the older drugs. At the time this study was conducted, the newer antidepressants SSRIs and the SNRIs were prescribed in the majority of cases. . The study data demonstrated significant problems in the dose and duration of antidepressant treatment in this population. The results of the present study should be used as a discussion tool by pharmacists with physicians in order to optimize prescription habits for antidepressant usage.

Keywords

Retrospective; prescribing patterns; antidepressant medications

Download this article as: 

Copy the following to cite this article: Prabha K. S, Mohanta G. P, Manavalan R, Prasanna P. M. Retrospective Utilization Patterns of Antidepressant Medications. Biomed. Pharmacol. J.2008;1(2)

Copy the following to cite this URL: Prabha K. S, Mohanta G. P, Manavalan R, Prasanna P. M. Retrospective Utilization Patterns of Antidepressant Medications. Biomed. Pharmacol. J.2008;1(2). Available from: http://biomedpharmajournal.org/?p=469

Introduction

Depressive disorder is one of the most prevalent forms of mental illness and is of major public health importance.  It is characterized by abnormal and persistent low mood, accompanied by other symptoms including sleep disturbance, loss of appetite, suicidal thoughts, impaired concentration and attention, guilt and pessimism. Symptoms vary in severity and the pattern of illness can range from an isolated and relatively mild episode, through recurrent episodes of moderate severity, to chronic and persistent severe illness¹ and it is clear the disorder has a significant impact on the quality of life and functional status of the patient².

The past decade has seen an increase in the number and type of antidepressants available to psychiatrists and other clinician’s. It is important to better understand current prescribing practices and to what degree these practices reflect research findings. The Agency for Health Care Policy and Research (AHCPR) guideline states that major depressive disorder (MDD) can be successfully managed with antidepressants, psychotherapy or a combination^3,4. Effective management of MDD with antidepressants requires adequate dose and duration of therapy. Six weeks of therapy are required before a clinical improvement can be observed. If patients completely respond to treatment, maintenance treatment is recommended, usually with the same drug at the same dosage over a period ranging from four to nine months which is usually the average duration of a major depressive episode. Olfson and others surveyed in 1993/1994 and found that the SSRIs were the preferred anti depressants in the out patient setting in 63% of cases and the TCAs nortriptyline was used in only 7% of visits. The trend to use selective serotonin reuptake inhibitor (SSRIs) more often than the older TCAs occurred without there being clear evidence to support greater efficacy or cost-effectiveness⁵.Adherence to guidelines is often compromised by an unsatisfactory course of therapy, leading to either premature interruption of the medication regimen or subtherapeutic dosing⁶. These problems were found mainly related to the use of older antidepressant medications (TCAs)^7,8 because of their less favorable side effect profile⁹. New antidepressants such as selective serotonin reuptake inhibitor SSRIs, have exhibited efficacy reates similar to those of TCAs, but they are safer, better tolerated and more convenient to take¹⁰. The purpose of this study was to examine prevailing prescribing practices in psychiatric services and to determine to what degree these practices reflect research findings.

Method

For the present study, patient profiles were reviewed retrospectively to quantify anti depressant prescribing practices. The study evaluated data recorded from February 2006 to January 2007 in private hospital in chennai. The data included information on age, gender, and marital status, first –line preferences in the treatment of depression, duration of therapy for a first episode of depression and frequency of consultation.

Patterns of Antidepressant use

Agency for health care policy and research (AHCPR) guidelines were used as a standard for evaluation of appropriateness of therapy regarding minimum therapeutic dose and adequate duration⁴. These guidelines specify that antidepressant drug therapy should continue for between four to six months.

Results

The total study population included 750 patients of which 59.05% of female and 40.93% of male. The marital status of the patients 84.53% married and only 15.46% unmarried (Table 1) 

Table 1: Study population characteristics.

Age	Number	Percentage	Number	Percentage	Number	Percentage	Marital status
group	of	of	of	of female	of male	of male
	patients n=750	patients	female				m	%	um	%
0-19	76	10.13	52	6.93	24	3.2	4	0.53	72	9.6
20-40	320	42.66	188	25.06	132	17.6	288	38.4	32	4.26
40-60	252	33.6	135	18	117	15.6	240	32	12	1.6
<60	102	13.6	68	9.06	34	4.53	102	13.6	0	0
Total	750	100	443	59.05	307	40.93	634	84.53	116	15.46

 

The SSRIs were prescribed most frequently 48% in the treatment of a newly case of major depression followed by the SNRIs 17% (table 2) Of the SSRIs fluoxetine 23% and sertraline 20% were favored. SNRIs, venlafaxine 17% were mostly prescribed.  Tricyclic used most frequently in the treatment of depression was imipramine 8%.  In case of MAOIs, 6.4% of mianserin and 1.2%, of moclobemide were prescribed. (Table 2) Mean dose received by the patients are given in (Table 3). Only 14% received a minimum of six months of continuous therapy during the study period. In comparison 60.93% of these patients received therapy for less than three months and 25.2% received continuous therapy for three to six months. (Table 4).In the first month of treatment the frequency of consultation by patients, only 35.46% of patients saw physician once per week.

Table 2: Antidepressant Therapy                                    

Anti depressants	Number of patients n=750	Percentage of patients
SSRI	363	48.38
Fluoxetine	169	22.53
Sertraline	152	20.26
Citalopram	35	4.66
Fluvoxamine	7	0.93
SNRI	125	16.66
Venlafaxine	125	16.66
TCA	64	8.53
Imipramine	60	8.0
Dotheipin	4	0.53
MAOIs	57	7.6
Mianserin	48	6.4
Moclobemide	9	1.2
Other depressant	111	14.78
Lithium	32	4.26
Haloperidol	32	4.26
Olanzapine Nitrazepam	27 20	3.6 2.66
Others	30	4.0

Table 3: Mean daily dose of antidepressant drugs.

Antidepressants Dosage	Number of patients	Mean Dose(mg)
Fluoxatine
20mg	114	26.50
40mg	55
Sertraline 50mg	140	52.63
100mg	7
150mg	5
Citalopram
20mg	30	22.85
40mg	5
Fluvoxamine
50mg	5	64.28
100mg	2
Venlafaxine
75mg	125	125
Imipramine
50mg	9
100mg	49	95.83
200mg	2
Dotheipin
75mg	4	75
Mianserin
10mg	37	10
20mg	11
Moclobemide
150mg	7	183.33
300mg	2

 

Table 4: Length of therapy for first episode depression.

Time	N	%
Less than three months	457	60.93
Three to six months	189	25.2
Six months or more	104	13.86

 

Table 5:Frequency Of consultation in the first month of treatment

Frequency of consultation	N	%
More than once per week	52	6.93
Once per week	266	35.46
Once every two weeks	309	41.2
Once every three weeks	77	10.26
Once every four weeks	32	4.26
Others	14	1.89

 

Discussion

This study does not address the relative effectiveness of different antidepressants in the treatment of different antidepressants in the treatment of depression but illustrates how these medications have been used. The specific antidepressant agents prescribed and the preference for the class were SSRIs 48% and SNRIs 17% over the TCAs 9%. According to this study, SSRIs agents are favored as first line treatment in a first episode of depression and are prescribed more frequently than TCA agents. The SSRIs were probably the drug class of choice because the side effects are better tolerated than the older drugs. Antidepressant therapy has demonstrated that these medications are often given at subtherapeutic doses for insufficient treatment duration! Clinical trials demonstrate that increasing the dose results in the medication becoming less acceptable to the patients. Consequently, dropout rates may grow as dose and length of therapy increase¹². Most physician were treating a first episode of depression for a period of three months and 35.46% patients saw physician once per week.

The present analysis of data reflected only patients actual rates of medication use and may not reflect the doses prescribed by the physicians. Because of the retrospective nature of the analysis, no confirmation of information reported on the data file was possible.

Conclusion

At the time this study was conducted, the newer antidepressants the SSRIs and SNRIs were prescribed in the majority of cases than the older antidepressants such as the TCAs and MOAIs they were probably favoured because their use was associated with fewer side effects and better patient compliance. The study data demonstrated significant problems in the dose and duration of antidepressant treatment in this population. Most important, previous research shows that failure to achieve an adequate course of therapy may result in an increase in the total cost of treatment^13,14. The results of the present study should be used as a discussion tool by pharmacists with physicians in order to optimize prescription habits for antidepressant usage.

References

1. Murray and Lopez A., The global burden of disease; a comprehensive assessment of mortality and disability from diseases, injuries and risk factors in 1990 cambridge, M A, Harvard University press, 3rd edn, 597-599, (1996).
2. Hays R.D, Wells K.B, Sherbourne C.D, et al. Functioning and well – being outcomes of patients with depression compared with chronic general medical illness. Arch Gen Psychiatry., 52, 11-19 (1995).
3. Depression guideline panel, Depression in primary care volume 1 : detection and diagnosis, Rockville, MD : U.S. Dept. of Health and Human services, U.S. Public Health Service, Agency for Health care Policy and Research, AHCPR publication no.93-0550. clinical practice guideline no 5, April (1993a).
4. Depression guideline panel, Depression in primary care volume 2. Treatment of major depression. Rockville, MD : U.S. Dept. of Health and Human services, U.S. Public Health Service, Agency for Health care Policy and Research, AHCPR publication no.93-0551. clinical practice guideline no 5, (April 1993b).
5. Olfson M, Marcus S.C, Pincus H.A, Zito J.M, Thompson J.W, Zarin D.S.; Antidepressant prescribing practices of outpatient psychiatrists. Arch Gen psychiatry., 55:310-6, (1998).
6. Eisenberg Treating Depression and anxiety in primary care. Closing the gap between knowledge and practice. N Engl J Med., 326: 1080-84, (1992).
7. Katon W, Von Korff M, Lin E., et al. Adequacy and duration of antidepressant treatment in primary care. Med care., 30 ; 67-76, (1992).
8. Katzelnick D.J, Kobak D.A, Jefferson J.W, et al. Prescribing patterns of antidepression medication for depression in HMO. Formulary 31: 374 (1996).
9. Rudorfer M.V, Manji H.K, Potter W.Z. Comparative tolerability profiles of the newer Vs older antidepressants., drug saf 10 : 18-46, (1994 ).
10. AndersonM, Tomerson B.M. The efficacy of selective serotonin re-uptake inhibitors in depression: a meta-analysis of studies against tricyclic antidepressants., J Psychopharmacol., 8 : 238-49, (1994 ).
11. MC Combs J.S, Nichol M.B, Stimmel G.L, et al. The cost of antidepressant drug therapy failure: a study of antidepressant use patterns in a Medicaid population. J clin Psychiatry., 51 :60-69, (1990).
12. Gregor K.J, Overhage J.M, Coons S.F, et al. Selective serotonin re-uptake inhibitor dose titration in the naturalistic setting. Clin Ther., 16: 306-15, (1994).
13. Rost K, Smith G.R, Matthews D.B, et al. The deliberate misdiagnosis of major depression in primary care. Arch Fam Med., 3 : 333-37 (1994).
14. Thompson D, Buesching D, Gregor K.J, et al. Patterns of antidepressant use and their relation al cost of care. AM J Manag care., 2 : 1239-46, (1996).