Nmalangu&ogunbanjoprofile Of Acute Poisoning In Rsa-july2009

Original Research: A profile of acute poisoning at selected hospitals in South Africa

A profile of acute poisoning at selected hospitals in South Africa N Malangu, GA Ogunbanjo

N Malangu, National School of Public Health, University of Limpopo. GA Ogunbanjo, Department of Family Medicine and Primary Health Care, University of Limpopo. Correspondence to: N Malangu, National School of Public Health, University of Limpopo (Medunsa Campus), Box 215, MEDUNSA 0204, Pretoria, South Africa. E-mail: [email protected]

The aim of this study was to characterise acute poisoning cases admitted to a number of selected hospitals in South Africa. All cases admitted to eight hospitals, from January 2005 to June 2005, were evaluated retrospectively. Data obtained from the hospital medical records included the following: demographic characteristics, toxic agents, length of hospital stay, circumstances of poisoning, morbidity and mortality information on the poisoned patients. From a total of 424 patients admitted for treatment, whose median age was 17.6 years, 57.8 % were females, and 89.6% black Africans. Fifty-nine percent of the poisonings were accidental, and the involved toxic agents were, in descending order: household chemicals (45.7%), modern medicines (17.5%), animal/insect bites (15.8%), agrochemical chemicals (9.7%), food poisoning (5.4%), drugs of abuse (3.3%), traditional medicines (2.4%), and plants (0.2%). Poisoning by drugs of abuse was commoner in males than females, but the percentage of females poisoned by all other toxic agents was higher than in males. Most patients spent less than two days in hospital, but more females (70.1%) than males (29.9%) stayed for more than two days. The overall case fatality rate was 2.4%. Of those who died, 80% were black Africans, aged 13 to 19 years and it was deliberate poisoning through drugs of abuse, carbon monoxide and agricultural chemicals. Acute poisoning reviewed in some selected hospitals in South Africa revealed that more black African females were involved, who spent more than two days hospitalised. The case fatality rate was 2.4%, mainly due to drugs of abuse, carbon monoxide and agricultural chemicals. These findings suggest that further studies are needed to understand the motivation(s) for this emerging problem and that these should focus primarily on the female black African. South Afr J Epidemiol Infect 2009;24(2):14-16

Introduction

while the rest were in Gauteng province. Data were collected using a pre-tested data collection form from records of patients admitted between January to June 2005. Data obtained included age, gender, toxic agents, length of hospital stay, circumstances of poisoning, and whether these poisoned patients had survived or died as a result of the poisoning. All patients with a diagnosis of poisoning were included. Toxic agents involved were classified based on their characteristics. The information regarding the circumstances of the poisoning incident was obtained from the patients’ files. One data collector per facility collated the data. Two data capturers entered the data using MS-Excel 2003 and the data were analysed using SPSS version 13. Descriptive statistics were used to describe the sample and p-values less than or equal to 0.05 were considered to be statistically significant. The statistical test for comparison used was the chi-square test.11 This test was performed to compare actual frequency counts against the null hypothesis for bivariate tabular analyses. Ethics approval for the study was obtained from the Research Ethics and Publications Committee of the Faculty of Medicine, University of Limpopo (Medunsa Campus).

Acute poisoning is a cause of both morbidity and mortality in many parts of the world. The toxic agents associated with the morbidity and mortality vary from place to place, and over time, due to the availability and use of various chemicals and other poisoning agents. In South Africa, recent reports suggest that acute poisoning is responsible for up 17% of total ward admissions in children.1,2 It is generally known that children under 10 years represent up to 80% of all victims of poisoning, and the majority of these poisoning incidents are unintentional.3,4 It is also known that more male than female children are victims of poisoning.5-7 Although mortality from acute poisoning is reportedly low, it is usually high in patients who are victims of suicide. 8-10 The aim of this study was to characterise acute poisoning cases admitted to a number of selected hospitals in South Africa during the first half of 2005. The objectives of this study were to determine the common toxic agents involved in poisoning, length of hospital stay, to compare outcomes with regard to gender and the case fatality rate of the acute poisoning cases.

Methods

Results

The study reviewed 423 cases of acute poisoning admitted to eight conveniently selected hospitals as part of the experiential attachment of a group of Master of Public Health students from the University of Limpopo (Medunsa Campus). Four hospitals were in KwaZulu-Natal,

South Afr J Epidemiol Infect

The majority of the acute poisoning cases were female, black Africans, whose median age was 17.6 years (range 1-74 years). The age group mostly affected was below 12 years of age (36.9%), and

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Original Research: A profile of acute poisoning at selected hospitals in South Africa

the least affected were those over 30 years (Figure 1). Household chemicals were the most commonly implicated poisons (45.7%), followed by medicines (17.5%), animal/insect bites (15.8%), agricultural chemicals (9.7%), food poisoning (5.4%), traditional medicines (2.4%) and plants (0.2%) (Table 1). Among the household chemical agents, paraffin was the most commonly ingested (26.9%), while among the agricultural chemicals, organophosphates were the most frequently implicated agents. Regarding the length of hospital stay, 70% of the victims of acute poisoning stayed for less than two days with the median duration of stay of 1.9 days (Table 2). Based on the variables reflected in Table 3, the majority of the patients were black Africans, with more females hospitalised longer than two days, and the majority of poisoning incidents due to drugs of abuse (64.3%) were in males. The majority of poisoning occurred accidentally, but deliberate poisoning was more prevalent in females (48.4%) than in males (31.3%). The case fatality rate was 2.4%. Of those who died, 60% were females (Table 3). Eighty percent were black Africans,

aged 13 to 19 years, due to poisoning from carbon monoxide (40%), drugs of abuse (40%), and organophosphates (20%), respectively (Table 4).

Table 1: Frequencies of study variables

Table 2: Age and length of hospital stay (LOS) parameters

Study variables

Percentage

Age category (n=423) 0 to 12 years

36.9

13 to 19 years

20.8

20 to 30 years

25.5

Over 30 years

16.8

Gender (n=423) Female

57.8

Male

42.2

Race (n=423) Black

89.6

Caucasian

7.8

Coloured

1.7

Asian

0.9

Length of hospital stay (n=290) Less than or equal to 2 days

70.0

More than 2 days

30.0

Circumstances of poisoning (n=423) Accidental

59.0

Deliberate

41.0

Outcomes (n=423) Survived

97.6

Died

2.4

Toxic agents involved (n=423) Household chemicals

45.7

Figure 1: Acute poisoning by age group and gender (n=423) 28.0

0 to 12 years

48.6 26.3

13 to 19 years

13.4 28.0

20 to 30 years

22.3 17.7

Over 30 years

15.6

00.0

10.0 Male

Study variables

Percentage

Medicines

17.5

Parameters

20.0

30.0 Percent

Female

40.0

50.0

Age in years (n= 423)

LOS in days (n=290)

Mean

18.1

2.4

Median

17.6

1.9

Unspecified medicine overdose

10.0

Paracetamol

3.5

Minimum

1.0

1

Carbamazepine

1.7

Maximum

74

26

Aspirin

1.4

Erythromycin

0.2

Cotrimoxazole

0.2

Chloroquine

0.2

Ascabiol Animal/insect bites

60.0

Table 3: Frequencies of study variables by gender Variables

Male

Female

41.2

58.8

Race

0.2

Black (n=379)

15.8

Snake bites

15.1

Caucasian (n=33)

51.5

48.5

Bee stings

0.2

Coloured (n=7)

42.9

57.1

Scorpion bites

0.2

Asian (n=4)

75.0

25.0

Spider bites

0.2

Agricultural chemicals

9.7

Organophosphates

5.9

Carbamates

2.6

Pyrethroids

0.9

Insecticides (Baygon®)

0.2

Food poisoning

5.4

Drugs of abuse

3.3

Cocaine

2.8

Marijuana

0.5

Traditional medicines

2.4

Plants

0.2

Length of hospital stay Less than or equal to 2 days (n=203)

46.8

53.2

More than 2 days (n=87)

29.9

70.1*

Accidental (n=249)

68.7*

51.6

Deliberate (n=174)

31.3

48.4

Survived (n= 413)

42.3

57.6

Died (n=10)

40.0

60.0

Circumstances of poisoning

Outcomes

Toxic agents involved

Paraffin

26.9

Unspecified

9.6

Sodium hypochlorite

2.4

Alcohol

2.4

Carbon monoxide

2.1

Thinners

1.3

Potassium permanganate

0.5

Power soap (Omo®)

0.2

Traditional medicines (n=10)

50.0

50.0

Glue

0.2

Carbon monoxide (n=9)

22.2

77.8

Chlorhexidine

0.2

Household chemicals (n=185)

42.7

57.3

Modern medicines (n=74)

44.6

55.4

Animal/insect bites (n=67)

40.3

59.7

Agricultural chemicals (n=41)

36.6

63.4

Food poisoning (n=23)

39.1

60.9

Drugs of abuse (n=14)

64.3

35.7

*p<0.05

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Original Research: A profile of acute poisoning at selected hospitals in South Africa

and public education on the topic of acute poisoning is warranted and the involvement of primary healthcare, namely general practitioners, nurses and pharmacists, is needed. Specific messages directed at creating more awareness on the danger of this unnecessary scourge must be designed and widely circulated.15 Secondly, legal approaches should include the enforcement of the existing legislation relating to the control of medicines. One practical regulatory approach should include measures aimed at strengthening the ethical responsibilities of pharmacists, dispensing doctors and nurses regarding advising patients on the safe use and storage of medicines bought over-thecounter or dispensed by them. In this study, 17.5% of poisoning incidents were due to medicines, namely aspirin, carbamazepine, and paracetamol. This finding is consistent with previous reports from other institutions in South Africa.1-3, 16

Table 4: Frequencies of study variables by fatal outcome (n=10) Variables

Percentage

Age category 0 to 12 years

0.0

13 to 19 years

80.0*

20 to 30 years

10.0

Over 30 years

10.0

Race Black

80.0

Caucasian

20.0

Coloured

0.0

Asian

0.0

Circumstances of poisoning Deliberate

70.0

Accidental

30.0

Finally, this study has some limitations. As a cross-sectional study design, cause and effect relationships could not be determined. In addition, the use of convenience sampling technique to select facilities did not make our findings generalisable as they are not representative of all hospitals in South Africa. But the findings provide vital information on the spectrum of acute poisoning, and common causes of mortality due to the phenomenon as seen in some of our hospitals. Hence further studies are needed, preferably cohort or interventional studies involving victims of poisoning to reduce the problem.

Toxic agents involved Drugs of abuse (cocaine)

40.0

Carbon monoxide

40.0

Agricultural chemicals

20.0

Traditional medicines

0.0

Modern medicines

0.0

Household chemicals

0.0

Food poisoning

0.0

Animal/insect bites

0.0

Conclusion Acute poisoning affected more black African women, who spent more than two days hospitalised, and resulted in a case fatality rate of 2.4%, mainly due to carbon monoxide, drug of abuse (cocaine) and organophosphates. These findings suggest that further studies are needed to understand the motivation(s) for this emerging problem and that these should focus primarily on the female black African.

*p<0.05

Discussion The majority of those poisoned were female, black Africans, whose median age was 17.6 years. This demographic distribution of poisoning cases is consistent with previously reported findings in which children younger than 12 years, and black females were the most affected by acute poisoning attributed to their developmental and contextual vulnerability.12,13 As reported by other investigators, young boys are twice as likely to be victims of poisoning than girls, but during the teenage period, the prevalence of acute poisoning in females increase almost two-fold compared to their male counterparts.1-5

Acknowledgements We thank the 2005 Master of Public Health students who were involved in the field work.

References 1. Malangu N. Poisoning in children from a rural community in South Africa. South Afr J Epidemiol Infect 2005; 20(3): 97-102 2. Reed RP, Conradie FM. The epidemiology and clinical features of paraffin poisoning in rural African children. Ann Trop Paediatr 1997; 17(1): 49-55 3. Joubert PH. Poisoning admissions of black South Africans. J Toxicol Clin Toxicol 1990; 28: 85-94 4. Eaton-Jones SE, Fields KB, Rasco T, Akintemi OB. Preventing childhood poisoning: an intervention in a family medicine residency program. NCMJ 2000; 61(6): 332-334 5. Van der Merwe PJ, Botha JJ. An epidemiological study of poisoning in children under 18 years old in the Bloemfontein area. S Afr Med J 1991; 79(5): 253-255 6. Ho L, Heng JT, Lou J. Accidental ingestions in childhood. Singapore Med J 1998; 39(1): 5-8 7. De Wet B, Van Schalkwyk D, Van der Spuy J, Du Plessis J, Du Toit N, Burns D. Paraffin poisoning in childhood - is prevention affordable in South Africa? S Afr Med J 1994; 84(11): 735-738 8. Du Plooy WJ, Jobson MR, Osuch E, Mathibe L, Tsipa P. Mortality from traditional medicine poisoning: a new perspective from analysing admissions and deaths at Ga-Rankuwa Hospital. S Afr J Science 2001; 97: 70 9. Ellis JB, Krug A, Robertson J, Hay IT, MacIntyre U. Paraffin ingestion: The problem. S Afr Med J 1994; 84(11): 727-730 10. Abebe M. Organophosphate pesticides poisoning in 50 Ethiopian patients. Ethiop Med J 1991; 29(3): 109-118 11. Armitage P, Berry G. Statistical methods in medical research. 3rd ed. Oxford: Blackwell Scientific Publications; 1994 12. Mathee A, Barnes B. Children, environment and health in South Africa (Editorial). Urban Health and Development Bulletin 2001; 4(2): 1 13. Eddleston M. Patterns and problems of deliberate self-poisoning in the developing world. QJM 2000; 93(11): 715-731 14. Stewart MJ, Moar JJ, Mwesigwa J, Kokot M. Forensic toxicology in urban South Africa. J Toxicol Clin Toxicol 2000; 38(4): 415-419 15. Malangu N, Ogunbanjo GA. Predictors of topical steroid misuse among patrons of pharmacies in Pretoria. SA Fam Pract 2006; 48(1): 14 16. Young RJ, Critchley JA, Young KK, Freebairn RC, Reynolds AP, Lolin YI. Fatal acute hepatorenal failure following potassium permanganate ingestion. Human Exp Toxicol 1996; 15(3): 259-261

In this study, the majority of poisoning cases were accidental but 70% of deaths occurred among those who committed suicide. This finding is consistent with those reported in the literature.10,14 As a result of these poisoning incidents, most victims in this study stayed in hospital for less than two days, but the majority of females as compared to males stayed for more than two days. This suggests that women, by virtue of being more likely victims of deliberate poisoning than males, experienced somehow more severe incidents that required more observation and/or treatment. This could be explained by the types of toxic agents involved. The three chemicals responsible for deaths, namely carbon monoxide, drug of abuse (cocaine), and organophosphates are all highly toxic substances. The findings of this study have a number of important implications. Firstly, it is crucial to understand the motivation(s) of female black Africans involved in acute poisonings before interventions can be designed to address the problem as women are both victims and caretakers of children and teenagers who need to be protected from acute poisoning. These interventions should be multi-dimensional involving educational, regulatory, and managerial approaches. Media

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