Author Name: Kannika Inpra Email: kungkannika@yahoo.com Presenter Name: Kannika InpraAuthors: Inpra K., Suwankesawong W., Kaewvichit S.Institution: Phrae Hospital, Phrae, Thailand Title: Preventable Adverse Drug Reactions in Hospitalized Patients: A Study in 21 Selected Thai Hospitals

Problem Statement: The high incidence of and costs associated with adverse drug reactions (ADRs) have influenced health care policy and e

conomics. To minimize this problem, it is essential to gain knowledge of preventable ADRs and develop intervention programs to tackle the pro

blem. In this study, the extent of preventable ADRs in Thailand was explored.Objective: To determine the incidence and characteristics of preventa bleADRs i n hospi t al i zed pat i ent s.Design: Prospective observational study.

Setting and Study Population: All case report forms of patients mor e than 18 years old admitted to the Department of Medicine in 21 seco

ndary and tertiary care hospitals located throughout Thailand from Feb ruary 1, 2002, through March 8, 2002, were examined.

Results: From 1 3 ,7 8 1 case reports, 3 6 3 ADR reports were an 114314alyzed. From this group, ( . %) were classified with Schumock an

d Thornton criteria as preventable ADRs. Mean age ± SD was 55.36 ± 6 .44 years. More than twice as many females as males (68:31) had ADRs

. The top three underlying diseases were hypertension, diabetes mellit - us, and tuberculosis. Eighty one (71.1%) preventable ADRs were relate

d to hospital admission. The median length of stay was four days (rang e, 0–34 days), with 82 (71.9%) reports considered severe enough to re

quire initial or prolonged hospitalization.[1] The relationship of prevent able ADRs to drug exposure was determined to be probable or possible

oo oo oo oooooooo oo ooo ooooooooooooooooo o oooooooo ooo o1 00%. , utritional, central and peripheral nervous, liver and biliary, and skin and

appendages systems. The most common outcome (65.7%) was recover o oooo oooo oooooooooooooo o ooooooooo o ooo o oooooo. , ,

aneous were the top three classes of drugs causing preventable ADRs. - The four highest priority causes of preventable ADRs accounted for 89

oooooooo ooooooooooo oooo o ooooooooo oo ooooo oooo% : ( 1 ) ssary laboratory tests were not performed or not performed frequently

468 2enough ( . %); ( ) dose, route, or frequency of administration was no 160t appropriate for the patient’s age, weight, or disease criteria ( . %); (

3) drugs prescribed were not appropriate for the patient’s clinical condi 132 4tion criteria ( . %); and ( ) noncompliance was associated with the re

132action criteria ( . %).

Conclusions: Further studies are needed to identify and determine ADR-associated factors and to develop strategies to avoid preventable ADRs in hospitalized patients.

Problem Statement

The high incidence and costs associated with adverse drug reactions : ADRs have influenced health care policy and economics. To minimize this problem, it is essential to gain knowledge of preventable ADRs and develop intervention programs to tackle the problem. In this study, the extent of preventable ADRs in Thailand were explored.

Objectives

To determine the incidence and characteristics of preventable ADR

in hospitalized patients.

Design

Prospective observational study

Setting and Population

All case report forms of patient more than 18 years old admitted to the department of

medicine in secondary and tertiary care hospitals located through out Thailand during February 1, 2002 to March 8, 2002 were explored.

Adverse Drug Reaction : ADRWHO definition (1966 )

Criteria for Determining Preventability of an ADR

Answering “YES” to one or more of the questions

• Was the dose, route, and frequency of administration not appropriate for the patient’s age, weight and disease state ?

• Was required therapeutic drug monitoring or other necessary laboratory test not performed ?

• Was the drug involved in the ADR not considered appropriate for the patient’s clinical condition ?

• Schumock GT and Thornton JP. Focusing on the preventability of adverse drug reactions. Hosp Pharm. 1992;27:538-9.

Criteria for Determining Preventability of an ADR cont.

• Was there a history of allergy or previous reactions to the drug ?

• Was a drug interaction involved in the reaction ?

• Was a toxic serum drug level documented ?

• Was poor compliance involved in the reaction ? Schumock GT and Thornton JP. Focusing on the preventability of adverse drug reactions. Hosp Pharm. 1992;27:538-9.

Results

• From 13,781 case reports, 363 ADRs reports were analyzed. From

this group, 114 (31.4 %) were classified with Schumock and

Thornton criteria as preventable ADRs.

• The relationship of preventable ADRs to drug exposure was

determined to be probable or possible in 100%.

• Most outcome (65.7%) was recovered without sequelae.

Variable No.( %)Preventable

ADR( n = 114, 31.40% )

No.( %)Non-preventable

ADR( n = 249, 68.60%

)

Age group 18-3839-5859-7879-98

 

 22 ( 19.30 )35 ( 30.70 )51 ( 44.74 )

6 ( 5.26 )

 60 ( 24.10 ) 78 ( 31.33 )92 ( 36.95 )19 ( 7.63 )

AgeMean SDRangeModeMedian

 55.36 6.44

87-2160

58.5

 

 53.92 18.53

93-197455

GenderMaleFemale

 

 36 ( 31.58 ) 78 ( 68.42 )

 123 ( 49.40 )126 ( 50.60 )

Table lPreventable and Non-preventable Adverse Drug Reaction ( ADRs ) Categorized by Patient and ADR Variables

Preventability Code

Criteria No. times code used

(% total uses)

1 Drugs involved were not appropriate for the patient’s clinical condition.

22( 13.02 )

2 Dose, route, or frequency of administration was not appropriate for the patient’s age, weight or disease.

27( 15.98 )

3 Required therapeutic drug monitoring or other necessary laboratory tests were not performed or not performed frequently enough.

79( 46.75 )

4 Patient has a history of allergy or previous reaction to the drug

13( 7.69 )

5 A known drug interaction was the suspected cause of the reaction

2( 1.18 )

6 A serum drug concentration above the therapeutic range was documented

4( 2.37 )

7 Noncompliance was associated with the reaction

22(13.02 )

Table ll Distribution of preventability Code

Most top three underlying diseases

Most top three classes of drugs causing preventable ADRs

• Other chemotherapeutics • metabolism • miscellaneous

Half of them occurred in

• Gastro-intestinal• Metabolic and nutritional• Central & peripheral nervous• Liver and biliary • Skin and appendages system

• Hypertension• Diabetes mellitus • Tuberculosis

Variable No. ( %)Preventable

ADR

No. ( %)Non-preventable

ADR

Admissions due to ADRYesNo

 

 81 ( 71.05 )33 ( 28.95 )

 115 ( 46.18 )134 ( 53.82 )

Length of stayMin – MaxMean SDMedianRange

 

 0 - 34

7.03 7.824

34

missing data = 3

 0 – 154

10.2 13.306

154

missing data = 9

Drug Allergy HistoryYes No

 

 14 ( 12.28 )

100 ( 87.72 )

 28 ( 11.67 )

212 ( 88.33 )

missing data = 9

Table IIPreventable and Non-preventable Adverse Drug Reaction ( ADRs ) Categorized by Admissions due to ADR, Length of stay and Drug Allergy History

Discussion The percentage of pADRs 31% The percentage of admission that were c

lassified as preventable 71.05% Values previously reported as being pre

ventable 28-80%

Conclusions

Further studies are needed to identify and determine ADR associated factors and to develop strategies for prevention of preventable ADRs in hospitalized patients