Title: Patterns of prescription and drug use in a psychiatry out-patient department in a teaching hospital in western Nepal

Shankar PR, Roy S, Shenoy N

Ravi Shankar M.D.

Department of Pharmacology

Manipal College of Medical sciences

Pokhara, Nepal.

Samit Roy M.D.

Department of Psychiatry

Manipal Teaching Hospital

Pokhara, Nepal.

Mr. Nagesh Shenoy

Department of Pharmacy

Manipal Teaching Hospital

Pokhara, Nepal.

Running title: Drug utilization in psychiatry

Address for correspondence:

DR.P.Ravi Shankar

Department of Pharmacology

Manipal College of Medical sciences

P.O.Box155

Pokhara, Nepal.

E-mail: mcoms@mos.com.np

pathiyilravi@rediffmail.com

Title: Prescription in a psychiatry out-patient department in a teaching hospital of western Nepal

Summary:

Aims: To find drug use patterns among out-patients attending the psychiatry OPD of Manipal teaching hospital, Pokhara, Nepal. Methods: The diagnosis, duration of treatment, drugs prescribed, strength, frequency, duration of treatment and the cost of prescription were analyzed in 239 patients. An attempt was made to relate prescription data to the age and sex of the patients. Results: Mean ± SD drugs per prescription was 1.55 ± 0.79 for men (n=115) and 1.89 ± 0.81 for women (n=124). 71.3% of the drugs were prescribed by brand names and the mean ± SD cost of drugs per prescription was 52.56 ± 43.45 Indian rupees. The prescribing frequency of antidepressants, anxiolytics, antipsychotics and antimania drugs were 45.94% (187/407), 19.41% (79/407), 8.6% (35/407) and 1.96% (8/407) respectively. Women were prescribed more antidepressants than the men. No clear trends were noted in prescribing frequency of drugs was observed. Conclusions: The issue of prescribing by brand names needs to be addressed. Studies on patient compliance and dropout rate from treatment are urgently required

Key words: Drug utilization Psychotropic drugs Psychiatry

Measurement of drug use identifies drug use patterns, prescribing behaviour and factors responsible for polypharmacy.¹ Setting standards and assessing the quality of care through performance review should be part of everyday clinical practice.² The study of prescribing seeks to monitor, evaluate and if necessary, suggest modifications in prescribing patterns so as to make medical care rational and cost effective. Rational drug prescribing is defined as the use of the least number of drugs to obtain the best possible effect in the shortest period and at a reasonable cost.

Medical audit oversees the observance of standards of medical care at all levels of the health care delivery system.³ It is concerned with the evaluation of medical care in retrospect through analysis of prescriptions or clinical records; to provide the full benefits of medical knowledge effectively and rationally.

Psychotropic medications are widely prescribed⁴ and the utilization of psychotropic drugs is increasing. However data on the utilization of psychotropic drugs are lacking in Nepal, particularly western Nepal. Therefore the present study was carried out in the psychiatric out-patient department of the Manipal teaching hospital, a tertiary care hospital in Pokhara, western Nepal.

All the patients attending the psychiatric OPD over a 46 day period (from 16.06.01 to 31.07.01) were covered in the study. All prescriptions from the psychiatry OPD were collected from the hospital pharmacy during the study period and analyzed. The information in the prescriptions was used to complete a customized proforma. The information recorded was: name, hospital number, age, sex, diagnosis (patient information); drug name, dose prescribed and duration of prescription (drug information). The cost of the drugs prescribed in each prescription was calculated using the price list made available from the hospital pharmacy. All the drugs prescribed in the psychiatry OPD were available in the hospital pharmacy.

The patients were classified according to sex in six age groups and the frequency of prescribing was calculated. Prescribing frequency was expressed as percentage of the number of times a particular drug/drug category was prescribed in a particular age/sex group to the total number of patients in the particular age/sex group.

We studied the percentage of drugs prescribed in the psychiatric OPD which were from the essential drug list of Nepal⁵ and WHO list of essential drugs list.⁶ The percentage of drugs prescribed by generic name and brand names were also noted. The number of combination preparations and the average cost of drugs per prescription calculated.

During the study period, 239 patients were seen in the psychiatric OPD and a total of 407 individual preparations were prescribed to 115 men (48.12%) and 124 women (51.88%). The total number of drug classes prescribed was 42. The average number of drugs per prescription for the men was 1.55 ± 0.79 (mean ± SD) and for the women the average number was 1.89 ± 0.81. Our findings match the results of earlier studies^7,8 that women patients were prescribed more psychotropic drugs than men. The difference was not statistically significant (Z value = 1.38).

Somatoform disorders were the most common complaint among the patients attending the psychiatry OPD (n=63). The other common disorders were anxiety (n=34) and depression (n=29). Mixed presentation of anxiety and depression were also seen.

Majority of the patients (86.19%) received less than 3 drugs per prescription. The drugs were prescribed for a time duration of 15 days. The average cost of drugs per prescription was 84.09 ± 69.52 Nepalese rupees. Eleven of the total of 42 drug classes prescribed (26.2 %) were from the essential drug list of Nepal⁵ and the same number were from the WHO list of essential drugs.⁶ There were differences in the drugs included in the two essential drug lists. Only 29.7% of the drugs were prescribed by generic names. Forty four of the total of 407 drugs prescribed were combination preparations.

Table 1 shows the gender based prescribing frequency of the different categories of psychotropic medications. The prescribing frequency of the tricyclic antidepressants (c ² value = 5.96) and selective serotonin reuptake inhibitors (c ² value = 8.7) were significantly more for women.

Majority of the patients attending the psychiatry OPD [196(82 %)] were below the age of 46 years. The most commonly prescribed categories of drugs were in descending order of frequency: tricyclic antidepressants (TCAs), anxiolytics/sedatives and selective serotonin reuptake inhibitors (SSRIs). Among the individual drugs the most commonly prescribed antidepressant was the SSRI Fluoxetine (41 patients) followed by the TCA Doxepin (33 patients). Analysis of prescribing frequency versus age is shown in Table 2. No clear trends of differences in prescribing frequency with age were observed.

A prescription provides an insight into the nature of the health care delivery system.⁷ The role of the psychiatrist in ensuring compliance to the drug treatment cannot be over-emphasized. The average number of drugs per prescription in an audit is important for review and educational intervention in prescribing practices. This is especially important in psychiatry as polypharmacy is common and psychotherapeutic drugs have been over-prescribed and misused.⁸ The average number of drugs per prescription in our study (n=1.75) is on the lower side. Only 13.72% of the patients received 3 or more drugs as compared to 40% reported from an Italian study.⁹

The cost of the prescription is an important variable in determining compliance to the treatment, especially in developing countries. Compliance is a variable which must be taken into account in the interpretation of the results of a given treatment. This is especially true in psychiatry because of the long duration of treatment and the high level of non-compliance (20-50%).⁹ The issue of compliance was not addressed in the present study. In the present study the issue of compliance to drug treatment was not explored. We plan to study this in a future study. The average cost per prescription in our study was 84.09 Nepalese rupees which is affordable by the majority of the patients.

A previous study¹⁰ have suggested that women receive more psychotropic medications than men. Women were significantly more likely to be prescribed psychotropic drugs of all types from a female physician than from a male.¹⁰ However, information on patient diagnosis and severity of symptoms were not taken into account in the particular study. In our study women were prescribed, on an average, more psychotropic drugs than men but the difference was not statistically significant. This is in agreement with a study carried out in Finland¹¹ where no gender differences were found. Women were prescribed significantly more antidepressants than men and this could be because of the higher incidence of depression and somatoform disorders in women.

Antidepressants were the most commonly prescribed class of psychotropic drugs in our study. This holds true across the different age groups and also in both genders. In most of the studies ^11,12 Benzodiazepines were the frequently prescribed psychotropic drugs. However, a longitudinal study carried out in the United States reports that the use of hypnotic drugs, previously the most frequently prescribed category, has declined and is now surpassed by antidepressant drugs.⁴ Tricyclic antidepressants remain the most frequently prescribed class of antidepressants and this is in consonance with other studies.^9,13

10.8 % of the drugs used were combination preparations and 26.2% of the drugs prescribed were from the essential drug lists of both Nepal and the WHO. 70.3% of the drugs were prescribed by brand names. These are issues of concern which can be redressed to some extent by prescriber education. The reasons often cited for the use of such combination preparations namely convenience, improvement in compliance and lower cost hold true in our OPD.

The value of medical audits for generating and testing hypotheses on inappropriate prescribing has resulted in educational interventions to improve prescribing patterns.¹⁴ The information can be used to develop adverse drug reaction monitoring programs also. Polypharmacy increases the risk of drug interactions and errors of prescribing. In our study the incidence of polypharmacy was low (1.75 drugs per prescription).

Further studies in patient compliance with treatment and the dropout rate from psychiatric treatment are required. Studies in prescription audit of psychotropic drugs can be conducted to investigate the scope for improvement in prescribing practices.

1. WHO action programme for Essential drugs. How to investigate drug use in health facilities. WHO, 1993.
2. Patterson HR. The problems of audit and research. J R Coll Gen Pract 1986;36:196.
3. Gupta N, Sharma D, Garg SK, Bhargava VK. Auditing of prescriptions to study antimicrobials in a tertiary hospital. Indian J Pharmacol 1997;29:411-15.
4. Pincus HA, Taniclian TL, Marcus SC, Olfson M, Zarin DA, Thompson J et al. Prescribing trends in psychotropic medications: primary care, psychiatry, and other medical specialities. JAMA 1998;279:526-31.
5. Department of drug administration, Nepal. National list of essential drugs. His Majesty's government of Nepal 1997 (second revision).
6. WHO. WHO model list of essential drugs. WHO Drug Information 1999;13(4):249-62.
7. Laporte JR. Towards a healthy use of pharmaceuticals. Development Dialogue 1985;2:48-55.
8. de Girolamo G, Williams P, Cappiello V. Psychotropic drug utilization and audit in two Italian psychiatric services. Psychol Med 1987;17:989-97.
9. Tognoni G. Pharmacoepidemiology of psychotropic drugs in patients with severe mental disorders in Italy. Italian collaborative study group on the outcome of severe mental disorders. Eur J Clin Pharmacol 1999;55(9):685-90.
10. Morabia A, Fabre J, Dunand JP. The influence of patient and physician gender on prescription of psychotropic drugs. J Clin Epidemiol 1992;45:111-16.
11. Joukamaa M, Sohlman B, Lehtinen V. The prescription of psychotropic drugs in primary health care. Acta Psychiatr Scand 1995;92(5):359-64.
12. Jacobsen GA, Friesen WT, Peterson GM, Rumble RH, Polack AE. Psychoactive drug prescribing in the Tasmanian community. Med J Aust 1992;157(1):20-24.
13. Munizza C, Tibaldi G, Bollini P, Pirfo E, Punzo F, Gramaglia F. Prescription pattern of antidepressants in out-patient psychiatric practice. Psychol Med 1995;25(4):771-78.
14. Hurley SF, Mc Neil JJ, Jolley DJ, Harvey R. Linking prescription and patient-identifying data: a pilot study. Med J Aust 1992;156:383-86.

* c ²= 5.96 p<0.05, * * c ²=8.7 p<0.05

+ SSRIs selective serotonin reuptake inhibitors