A survey of admissions following self-poisoning

AIMS AND METHOD

Patients who self-poison are at increased risk of future self-poisoningand early death. Admission patterns and effective treatmentstrategies are unclear although psychosocial assessment mayreduce readmissions. This study aimed to determine admissionpatterns and the proportion of patients receiving a psychiatricassessment in 4220 consecutive admissions.

RESULTS

The average age was 34 years (s.d.=13, range 13-94); most werefemale (56 v. 44%, P<0.001). Twelve per cent of patientswere aged 13-18 years, again the majority were female (70 v.30%, P<0.001). Twenty per cent of patients had multipleadmissions, accounting for 42% of the total admissions. Therewere slightly more admissions per day at the weekend (Friday,Saturday and Sunday; P<0.002). As many as 245 patients wereeither not referred or ‘self-discharged’ beforethey were assessed by the liaison psychiatry service.

CLINICAL IMPLICATIONS

These findings may help target medical resources, suggestingthat consistent numbers of staff are required during all daysof the week.

Introduction

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Introduction

Self-poisoning is common (Hawton et al, 1997) and the mostfrequent cause of hospitalisation involving self-harm in theUK. Although most patients do not present with a life-threateningcondition, and the need for urgent medical intervention is theexception rather than the rule, the majority require admissionfor observation. There are a significant number of readmissionswith this condition; 15-23% of patients have a further admissionwithin 1 year (Bialas et al, 1996; McEvedy, 1997; Van derSande et al, 1997; Hawton et al, 1999). These patients representa significant continuing danger to themselves, with around4% dying by suicide in the subsequent 5-10 years (Gunnell & Frankel, 1994).Treatment of these patients to prevent readmissionis difficult (Hawton et al, 1998; Bennewith et al, 2002),with no definite strategies of proven benefit, although a recentstudy suggested that patients who received a psychosocial assessment were half as likely to poison themselves again (Kapur et al,2002). Many factors determining such behaviour have been proposed,some of these, such as events or anniversaries, are specificto each patient (Beratis et al, 1996), but other factors relateto external influences and include times of the year (Beratis et al, 1996;Suhail & Cochrane, 1998) and days of theweek (Hulse et al, 2001). Predicting admission patterns maybe used to focus medical care and improve management and perhapseven prevent self-poisonings. The aims of this study were todefine admission patterns following self-poisoning in a districtgeneral hospital in Scotland and to determine, in a subsetof patients, what proportion are reviewed by the liaison psychiatry service.

Method

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Method

This was a retrospective case review of 4220 admissions to themedical wards of two Scottish district general hospitals withinthe same National Health Service (NHS) trust. Patients wereselected if they had been admitted following self-poisoningbetween January 1997 and June 2002. Cases of accidental poisoningwere excluded. Patients were identified by coding records witha diagnosis of self-harm due to self-poisoning. A subset ofpatients admitted over the past 6-month period were studiedto determine what proportion were reviewed by the liaison psychiatryservice. The following parameters were recorded: age, gender,day of admission (from midnight), admitting ward, length ofstay. The data were entered into a spreadsheet for furtheranalysis (Microsoft Excel version 5). Differences between groupswere determined by chi-squared analysis and significance takenat the 5% level. Data are given as means (s.d.) or as percentages.

Results

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Results

Patient demographics
The average age was 34 (range 13-94) years. There were morefemales (2399 (56%) v. 1821 (44%); P<0.001; Fig. 1). Therewere 501 patients (12%) aged 13-18 years; the majority of thesepatients were female (351 (70%) v. 150 (30%), P<0.001; Fig. 2).

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Fig. 1. Age at presentation.

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Fig. 2. Gender distribution for admissions of those under the age of 20 years.

Admission details
There was a total of 3723 (88%) admissions to a general medicalward. There was a small number of admissions to high dependencyareas; either a high dependency unit (211; 5%) or intensivecare unit (96; 2%). Owing to a shortage of medical beds, therewere 190 admissions directly to a bed on a surgical ward. Theaverage stay was longer for those admitted to a high dependencyarea than to a general ward (3.0±5.3(range <1-64days)v. 1.5±1.9 (range 1-42 days); P<0.001). There wasno difference in the length of stay between admission to ageneral medical ward or to a surgical ward.

Readmissions
A total of 588 patients had multiple admissions with a diagnosisof self-harm due to self-poisoning during the study period.These patients were responsible for 1790 admissions (42%);356 patients had 2 admissions, 121 patients had 3 admissions,40 patients had 4 admissions, 71 patients had more than 4 admissionsand 14 patients had 10 or more admissions (Fig. 3). In general,patients were readmitted early with 234 readmitted within 30days (Fig. 4). There was no difference in the proportionsof females who had multiple or single admissions during thestudy period (58 v. 57%, P=0.8) or mean age of those with multipleor single admissions (34 (s.d.=12) v. 34 (s.d.=13) years, P=0.6).There was no difference in the numbers of patients who hadmultiple or single admissions on different days of the week (P=0.2).

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Fig. 3. Frequency of repeat admissions.

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Fig. 4. Time between readmissions.

Timing of admission
There were slightly more admissions at the weekend, with 1905admissions (45%) occurring between Friday and Sunday (P=0.002).There was no difference in age (P=0.07) or gender (P=0.45)between those admitted on weekdays or at the weekend.

Number of admissions
The average number of admissions per month was 43 in 1997. Therewas an increase to 68 per month in 1998, which remained constantin subsequent years.

Psychosocial assessment
During the latter part of the study a psychiatric liaison nursewas available for referral at one of the hospitals during officehours (09.00 h to 17.00 h). Out-of-office hours cover was providedby the psychiatry doctor. Referral patterns were reviewed forthis period. During the past 6 months of the study period therewere 107 adult admissions to one of the hospitals. Of these10 (9%) were not referred, 16 (15%) self-discharged before theywere assessed by the liaison psychiatry service, 43 (40%) werereviewed by the liaison nurse and 34 (32%) were reviewed bythe on-call psychiatric doctor.

Discussion

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Discussion

This study has shown that admission due to self-poisoning iscommon in this NHS trust, occurs in young patients with anover-representation of females particularly in the youngestage-group, and many patients have multiple admissions. Thereare more admissions at the weekend. There were no differencesin patient demographics between those who presented at the weekend or those with multiple admissions. A significant proportionof patients do not receive a psychosocial assessment.

Although admission rates due to self-poisoning are reportedto be increasing (Bialas et al, 1996; McEvedy, 1997), thenumbers of admissions remained similar throughout the periodof our study. However, there were a large number of patientswith multiple admissions (20%). This is consistent with thefindings from other studies with readmission rates varyingbetween 9 and 23% depending on the length of the study andlocation (Bialas et al, 1996; McEvedy, 1997; Van der Sande,1997; Hawton et al, 1999). The frequency of readmission soonafter the initial admission suggests that the conditions leadingor predisposing to the episodes of self-harm are not resolvedand that more research is required in this area. Although other studies have demonstrated higher readmission rates among femalespatients, in our study there was no gender or age differencebetween patients who had single or multiple admissions.

Our study has demonstrated an alarming number of younger patients,with a particular over-representation of females in the youngestage-group (13-18 years). There was a steady increase in thenumber of male patients in the 13- to 18-year age-group althoughthe numbers of younger females were consistently higher inthis age-group. These younger patients were admitted to an adult general medical ward for medical care and perhaps this is notappropriate for this age-group. This raises an important issuewith regard to providing appropriate facilities and trainedstaff to cater for the needs of these adolescent patients.

More of our patients were admitted during the weekend days (Fridayto Sunday) than the week days although this was a small difference.Weekends are associated with increased alcohol consumption (Engeland & Kopjar, 2000; Chenet et al, 2001; Hulse etal, 2001), violent accidents (Nunez et al, 2000) and self-harm(Hulse et al, 2001) in many countries. An increase in consumptionof alcohol may explain the increase in admissions at the weekend in our patients, although other psychosocial behaviour patternssuch as domestic violence may also contribute. This is an importantobservation as the emergency department and medical wards mayalso be busier at these times with the non-medical consequencesof excessive alcohol misuse. Increased and better-targetedmedical resources may be of benefit at these times to cope withthe increased numbers of admissions following self-harm.

The majority of patients admitted to the medical unit following self-poisoning will come to no immediate harm, however, thisis a recurrent problem associated with significant morbidityand mortality in the medium- and long-term. Patients oftenpresent difficult and complex psychosocial problems that areresistant to treatment. This may be exacerbated by a combinationof inadequate NHS resources and uncertainty over effectivemanagement strategies. However a recent study has demonstratedthat a psychosocial assessment at the time of admission canreduce subsequent readmission rates (Kapur et al, 2002). Inour study 24% of patients did not receive assessment by theliaison psychiatry service, either because they were not referredor they had self-discharged before review.

Conclusion

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Conclusion

This study has shown that admission due to self-poisoning iscommon, although the absolute numbers did not increase overthe time of the study, and that there are more admissions atthe weekend. These results support the need for consistentnumbers of medical, nursing and ancillary staff during all days of the week to provide optimal care for patients followingan episode of self-poisoning. Adequate provision of psychiatricand social support is particularly important to ensure accessfor a greater number of patients.

Acknowledgments

We thank the medical records and audit departments at Falkirkand District Royal Infirmary, Scotland for their help in datacollection.

References

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