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South West Tuberculosis Treatment Outcome Surveillance for the South West 2001 - 2004

Outcome Surveillance

2001 -2004

Enhanced National Tuberculosis Surveillance: South West Region Report 2001 - 2004

2 HPA South West

TB Outcome Surveillance2001 - 2004

Data for the South West Region, England

A report from the Health Protection Agency

South West

Authors: Rebecca Close - Epidemiological and Surveillance Analyst

Isabel Oliver - Regional Epidemiologist

HPA (SW) February 2007


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Please note this is a web version of the report, the full report is available on request Acknowledgements The Enhanced Surveillance of Tuberculosis including treatment outcome monitoring functions with the co-operation and valuable input of clinicians, tuberculosis and clinic nurses, microbiologists and other hospital and clinic staff who provide the important information on tuberculosis cases. We gratefully acknowledge the continuing work and collaboration of our district tuberculosis co-ordinators: (Maggie Barlow, Sarah Harris, Vivienne Haynes-Smallbone, Toni Bowen, Jenny Hayward-Karlsson, Julie Mann, Judith Ralphs, Brian O’Neil, Katherine Butler and Lucy Nicholas) for their work in the collating and co-ordination of district enhanced tuberculosis surveillance data at local level. I would also like to thank Sam Organ and Isabel Oliver for their input.


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Contents

1. Outcome Surveillance Key Findings

2. Introduction

3. Background

4. Methods

4.1 Definitions

4.2 Analysis

4.3 Proportion of treatment completion

5. Results

5.1 Completeness of results

5.2 Comparing cases with outcome information and total number of cases reported

5.3 Overall results by outcome category

5.4 Deaths

5.5 Analysis of outcome data excluding patients who have died and transferred out

5.6 Analysis of treatment completion according to case characteristics

5.6.1 Previous history of tuberculosis

5.6.2 Site of disease and microscopy results

5.6.3 Age and sex

5.6.4 Place of birth

5.6.5 Ethnic group

5.7 Reasons for non-completion of treatment

5.7.1 Overall results

5.7.2 Cases still on treatment

5.8 Reasons for non-completion of treatment according to case characteristics

5.8.1 Previous history of tuberculosis

5.8.2 Site

5.8.3 Drug susceptibility testing results

5.9 Completion of the South West

6. Discussion

7. References


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Outcome Surveillance

1. Key Findings Overall findings

• Information on outcomes was reported for 87% of eligible tuberculosis cases reported between 2001 and 2004. This figure ranged from 94.6% in 2002 to 74.3% in 2004

• Of those cases with an outcome reported, 68.3% had completed treatment at

one year. This figure ranged from 64.3% in 2002 to 70.2% in 2003 Key findings excluding patients that died or transferred out

• 78.1% had completed treatment at one year. This figure ranged from 79.5% in 2001 to 75.4% in 2002 • Among the cases where treatment was not completed 7.7% were lost to follow up, 7.0% were still on treatment, 3.6% stopped treatment, 3.5% was unknown or missing and 0.1% the treatment was not completed (no reason given) • The proportion of treatment completion was similar in patients with pulmonary

tuberculosis than in extra-pulmonary tuberculosis cases (77.5% vs. 79.3%P=0.584)

• In the pulmonary cases with a positive sputum smear result, the proportion of

treatment completion was 75.4%

• Treatment outcome was very similar between males and females (77% vs. 79.8% P=0.385)

• Treatment completion was significantly lower in non-UK born cases compared

to UK born cases (72.1% vs. 85.6% P<0.001)

• 10-19 age groups had the lowest percentage of treatment completed, 0-9 age group had the highest percentage completed

• 2 cases had MDRTB during the period 2001-2004. Both cases occurred in Avon

and completed treatment

• These outcome results should be interpreted with caution since:

o Outcome information was missing for 13% of cases reported in 2001 - 2004.

o Using 12 months from start to finish of treatment as the cut off to access outcome may mask details of events occurring during the course of treatment.


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2. Introduction This report presents the results on treatment outcome surveillance among tuberculosis cases reported in 2001 to 2004 through Enhanced Tuberculosis Surveillance in the South West. The data presented in this report is correct as at February 2007. 3. Background The implementation of continuous monitoring of treatment outcome began in 2002, on tuberculosis cases reported in 2001, as part of the Enhanced Tuberculosis Surveillance. Outcome surveillance provides monitoring on patient’s status 12 months after the start of treatment. Clinicians who had reported a case of tuberculosis in the previous year were asked to complete a short form detailing the patient’s status. It is an essential means to determine the effectiveness of the national effort to control tuberculosis by providing insight into the proportion of patients who either complete treatment, die, experience complications resulting in changed or prolonged drug therapy, or who are lost to follow up prior to finishing treatment. A protocol drawn up by the International Union Against Tuberculosis and Lung Disease (IDATLD) was implemented in January 2002 for tuberculosis cases reported in 2001 as part of the Enhanced Tuberculosis Surveillance and was mainly based on European recommendations on treatment outcome monitoring published in 1998. These European standard indicators and definitions were adapted for use in the UK . One of the main purposes of treatment outcome monitoring is to determine the outcome of potentially infectious cases in order to provide information in likely transmission of the infection. The European recommendations defined the cohort for observation as all confirmed pulmonary cases. However for the purpose of treatment outcome surveillance in England, Wales and Northern Ireland, the outcome of all Tuberculosis patients was collated in order to take into account the large proportion of extra-pulmonary cases, that occurs in the foreign born population (cases in the foreign-born population represented 41.6% of all tuberculosis cases reported between 2001 and 2004.) 4. Methods 4.1 Definitions

• Tuberculosis case definition All new tuberculosis cases (culture confirmed cases and other than culture confirmed cases) should be reported. Culture confirmed cases: Culture confirmed disease due to Mycobacterium tuberculosis complex (M. tuberculosis, M. bovis or M. africanum). Other than culture confirmed cases: In the absence of culture confirmation, a case that meets the following criteria:

a) Clinician’s judgment that the patient’s clinical and/or radiological signs and/or symptoms are compatible with tuberculosis

b) Clinician’s decision to treat the patient with a full course of anti-tuberculosis treatment

Persons receiving preventive chemoprophylaxis are not to be reported (but may be reported by letter if required locally). • Cohort definition A cohort is defined as a group of people who are followed or traced over a specified period of time, and for treatment outcome surveillance consists of the group of patients whose anti-tuberculosis treatment outcome is to be reported. For treatment outcome surveillance in England, Wales and Northern Ireland, the cohort was defined as all tuberculosis cases reported to the Enhanced Tuberculosis Surveillance system during a specified period (12 months) including cases with a post-mortem diagnosis and excluding the denotified cases. Information on


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outcome relates to the patient’s status at 12 months after starting treatment (or diagnosis or notification date where the date of start of treatment is not available). • Treatment completion A patient is defined as having completed treatment if:

a) She/he was reported (culture confirmed or other than culture confirmed) b) And she/he has completed a full course of treatment c) And she/he was officially discharged by the attending physician

• Treatment stopped Treatment may be stopped because the patient was misdiagnosed or subsequently found not to have tuberculosis, or for another reason not listed in any of the other categories. • Cure A case is defined as cured if

a) She/he has completed a full course of anti-tuberculosis chemotherapy within 12 months of starting treatment, diagnosis or notification.

b) A documented culture conversion in sputum positive patients during treatment, i.e. culture positive at start of treatment becoming culture negative.

The outcome ‘cured’ was only to be used for pulmonary tuberculosis cases. • Death The outcome ‘death’ is used for patients who died before or during treatment. Postmortem cases are included in deaths. Four subcategories were used to provide information on the nature of the link between death and tuberculosis:

a) Tuberculosis caused death b) Tuberculosis contributed to death c) Tuberculosis incidental to death (tuberculosis was not related to death) d) Relationship between tuberculosis and death unknown

• Still on treatment This category was used for patients still on treatment at one year after starting treatment. Subcategories were used to provide information on reasons for being still on treatment:

1. Still on initially planned treatment (regimen longer than 12 months planned at the commencement of treatment) 2. Treatment was interrupted (non-completion of treatment regimen initially planned for 12 months or less (but still taking initially planned combination of drugs)) 3. Treatment was changed i.e. change and/or extension of drug regimen as a result of:

a) Intolerance / side effects b) Initial drug resistance c) Development of new drug resistance d) Failure to culture convert e) Poor clinical response to treatment

• Lost to follow up The patient is classified in this category if lost to follow up before the end of the treatment. • Transferred out The patient is classified as ‘transferred out’ if responsibility for his/her care was transferred to another clinical team. • Unknown When no treatment details (including outcome) are available (e.g. lost patient notes), the patient is classified as having an unknown outcome. • Multi drug resistant tuberculosis (MDRTB) Multi drug resistant tuberculosis is defined as a resistance to Isoniazid and Rifampicin, with or without resistance to another drug.


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• Pulmonary tuberculosis A pulmonary case is defined as a case of tuberculosis involving the lungs and/or tracheobronchial tree with or without extra-pulmonary diagnosis. • Previous history of tuberculosis ESTB collects information on previous tuberculosis diagnosis and on previous anti-tuberculosis treatment. A previously treated case is a case who was diagnosed with tuberculosis and took anti-tuberculosis drugs (excluding preventive therapy) for at least one month for a previous episode of tuberculosis other than the one reported. 4.2 Analysis The outcome surveillance data was analysed to measure the operational effectiveness of tuberculosis aftercare at local and regional levels. Cross checking for inconsistencies was carried out and some cases were reclassified according to additional information provided on the outcome form. Data on drug resistance was obtained via The Centre for Infection (CfI) from MycobNet and matched with the enhanced TB surveillance data. 4.3 Proportion of treatment completion According to the protocol used for England, Wales and Northern Ireland, the recommended method of calculation for the proportion of treatment completion was: Numerator: All tuberculosis cases completing treatment within one year of starting treatment or being formally notified. Denominator: All tuberculosis cases reported excluding: • Any tuberculosis patients for whom treatment was stopped because they were

subsequently recognised not to have tuberculosis • Any tuberculosis patients who were still on an initially planned course of treatment

at 12 months However, four different denominators could be used to calculate the overall proportion of treatment completion:

a) All cases with outcome reported b) All cases except those still on initially planned treatment c) All cases who effectively started treatment (i.e. excluding post-mortem cases) d) All cases reported in 2001 - 2004.

Further data analysis has been carried out among all cases with outcome reported (method a) since the calculation recommended in the protocol does not allow strict comparison of the cases with treatment completed (calculated among all cases minus those still on initially planned treatment) and those who have not completed their treatment (calculated among all cases)1. Data were also analysed excluding cases that had died (including cases diagnosed through post mortem) and cases that had transferred out, this is because these patients wouldn’t have been able to complete their treatment at 12 months.


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5. Results – South West 5.1 Completeness of the results 1002 tuberculosis cases were reported between 2001 and 2004 in the South West region, of these 99 cases were subsequently identified as not having TB (often diagnosed with non tuberculosis mycobacterium), leaving 903 notified cases. 786 (87%) of the notified cases had an outcome form returned with outcome information, this includes cases that did not have an outcome form completed but were classified by post-mortem diagnosis and were therefore included in the analysis as deaths. The overall proportion of outcomes received in the South West varied from 94.6% in 2002 to 74.3% in 2004 (figure 1). The Chief Medical Officer’s (CMO) Tuberculosis Action Plan for England2 recommends that all patients diagnosed with tuberculosis should have an outcome recorded. Within the region the proportion of outcomes received varied considerably; Dorset had 100% of outcomes received for 2001 - 2004, closely followed by Gloucestershire then Wiltshire. Devon had the lowest proportion of outcomes received in 2001 and 2002, Cornwall and Isles of Scilly and Somerset had the lowest proportion of outcomes received lowest in 2003; and Cornwall and Isles of Scilly had the lowest proportion of outcomes received in 2004.

Figure1: Proportion (%) of tuberculosis cases with outcome received by HPT and year 2001-2004 in the South West Region (Source: Enhanced Outcome Surveillance) 5.2 Comparing cases with outcome information and total number of cases reported The key information on the 786 cases with outcomes reported from 2001 - 2004 was compared with the same information on the total number of cases reported 2001 - 2004 (903). Table 1 shows that tuberculosis cases with known outcome status were also very similar to all cases reported for key demographic variables as well as site of disease, previous history of tuberculosis and culture result. Analysis for this report was therefore performed among all cases with an outcome reported and may be assumed to be representative of all cases for key information.

010

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Avon

Cornwall

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Dorset

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2001 2002 2003 2004


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Total Cases Cases with outcome reported*

Cases without outcome reported Reported**

2001 - 2004 2001 – 2004 2001 – 2004 Information collected (n=786) (n=117) (n=903) Male % 62.1 50.4 60.6 Median age 49 39 47 Born abroad % 40.6 50.4 41.9 Previous tuberculosis diagnosis % 10.6 6.8 10.1 Pulmonary % 71 56.4 69.1 Positive culture % 27.9 23.1 27.2

Table 1. Comparison of key information on all tuberculosis cases reported and tuberculosis cases with and without outcome reported in the South West Region (Source: Enhanced Outcome Surveillance) *Including cases with post mortem diagnosis ** Excludes cases which have been denotified 5.3 Overall results by outcome category

Of the 786 tuberculosis cases with outcome status reported in 2001 - 2004, 537 (68.3%) had completed treatment at one year, this figure ranged from 64.3% in 2002 to 70.2% in 2003. The most common reason for non-completion of treatment was death (12.2% 2001-2004), followed by lost to follow up (6.7% 2001-2004) and still on treatment (6.1% 2001-2004) (table 2). In 2004 79% of cases with an outcome reported completed treatment in England, Wales and Northern Ireland, this figure was higher than in the South West (69.5%). The CMO recommends that at least 85% of all patients should successfully complete their treatment2.

%

Treatment outcome category 2001 2002 2003 2004 2001-2004

Overall

Completed treatment 69.7 64.3 70.2 69.5 68.3 Died within 1yr of starting treatment (includes cases diagnosed by post mortem)

12.4 14.3 10.1 11.7 12.2

Lost to follow up 4.0 6.7 6.7 9.6 6.7 Still on Treatment 6.5 7.6 4.5 5.6 6.1 Transferred Out 0.0 0.5 0.0 0.5 0.3 Treatment stopped 5.0 2.9 3.9 1.0 3.2 Treatment not completed (no reason) 0.0 0.0 0.0 0.5 0.1 Unknown/missing 2.5 3.8 4.5 1.5 3.1

Total 100 100 100 100 100 Table 2: Tuberculosis Treatment Outcome Surveillance for Patients Notified in the South West region 2001-2004 (Source: Enhanced Outcome Surveillance) 5.4 Deaths 96 deaths (including cases that were diagnosed by post mortem) were recorded between 2001 and 2004. Of the tuberculosis cases that died 94.8% reported a cause of the death. Of the cases reporting a cause, 15.4% died as a direct result of tuberculosis (figure 2). Where the relationship between TB and the cause of death was known, tuberculosis caused or contributed to 42.8% of reported deaths. TB was incidental to the death in 23.1% of cases, and for 34.1% of the deaths the relationship between TB and the cause of death was unknown. 85.4% of the cases that died had pulmonary TB and 67% were over 70 years old.


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Figure 2: Causes of death among cases reported 2001 - 2004 in the South West region (Source: Enhanced Outcome Surveillance) _______________________________________________________________________________

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5.5 Analysis of outcome data excluding patients who have died and transferred out Patients who died (or were diagnosed through post mortem) within the year of starting treatment wouldn’t have been able to complete treatment, similarly patients who transferred out to another clinical team to continue their treatment wouldn’t have been able to report a completion of treatment to the South West. It was decided to exclude cases that have died or transferred out as “non-completion of treatment” from the analysis. 96 patients died or were diagnosed through post mortems between 2001 and 2004 in the South West and 2 patients transferred out during the same period. For this next section of the report “non-completion of treatment” will be classified as: Lost to follow up, Still on Treatment, Treatment stopped, Treatment not completed (no reason) and Unknown/missing. If the proportion of cases completing and not completing treatment is classified again according to the new criteria above for the period 2001-2004, 78.1% (n=537) of tuberculosis cases completed treatment and 21.9% (n=151) cases did not complete treatment (table 3 and figure 3). Please note, the data excluding deaths and cases that have transferred out cannot therefore be compared further against the CMO recommendations. Table 3: Tuberculosis Treatment Outcome Surveillance excluding cases that have died or transferred out for patients notified in the South West region 2001-2004 (Source: Enhanced Outcome Surveillance)

Treatment stopped

4%

Unknow n/missing

4% Treatment not completed (no

reason)<1%

Treatment completed

78%

Lost to follow -up8%

Still on treatment7%

Figure 3: Tuberculosis Treatment Outcome Surveillance for patients notified in the South West region, excluding patients who have died or transferred out 2001 - 2004 (Source: Enhanced Outcome Surveillance)

%

Treatment outcome category 2001 2002 2003 2004 2001-2004

Overall Completed treatment 79.5 75.4 78.1 79.2 78.1 Lost to follow up 4.5 7.8 7.5 11.0 7.7 Still on Treatment 7.4 8.9 5.0 6.4 7.0 Treatment stopped 5.7 3.4 4.4 1.2 3.6 Treatment not completed (no reason) 0.0 0.0 0.0 0.6 0.1

Unknown/missing 2.8 4.5 5.0 1.7 3.5

Total 100.0 100.0 100.0 100.0 100.0


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5.6 Analysis of treatment completion according to case characteristics 5.6.1 Previous history of tuberculosis The percentage of treatment completion was very similar in patients who had had tuberculosis prior to the current episode to those who had never previously had tuberculosis between 2001 and 2004 (77.9% vs. 78.1% P=0.981). 5.6.2 Site of disease and microscopy results Between 2001 and 2004 the proportion of treatment completion was similar in patients with pulmonary (with or without extra pulmonary disease) tuberculosis as in extra-pulmonary tuberculosis cases (77.5% vs.79.3% P=0.584). In pulmonary cases with a positive smear result, the proportion of treatment completion was 75.4% (2001 - 2004). Among the 475 pulmonary (with or without extra pulmonary disease) cases between 2001 and 2004, 183 (38.5%) were culture positive of which 138 (29.1%) had completed their treatment and of those 42 (8.8%) cases had been cured. 5.6.3 Age and Sex Treatment completion was very similar in males and females for all years, as well as overall between 2001 and 2004 (79.8% of females completed treatment and 77% of males P=0.385). Reasons for non-completion differed between males and females. The proportion of non-completion of treatment due to being lost to follow up was greater in males than females. In contrast, higher proportions of females stopped treatment or are still in their initial treatment plan. A similar proportion of males and females had an outcome unknown/missing (figure 4). Figure 4: Reasons for non-completion of treatment (not including cases that have died or transferred out) by sex among cases 2001 - 2004, in the South West (Source: Enhanced Tuberculosis Surveillance) *No reason given for non-completion 0-9 age group had the highest proportion of treatment completed and 10-19 age group had the lowest proportion. The proportion of treatment completion varied slightly by sex and age group (figure 5), although overall there was no clear association. Reasons for non-completion of treatment also differ slightly with age. ‘Lost to follow up’ was the most frequent reason for non-completion in the 20-29, 30-39 and 50-59 age groups. ‘Still on treatment’ was the commonest reason for non-completion of treatment in the 10-19, 40-49, 60-69 and 70-79 age groups. Unknown/missing data was the highest in the 80+ and 0-9 age groups.

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Figure 5: Proportion of treatment completion (not including cases that have died or transferred out) among cases reported 2001 - 2004 by age group and sex in the South West region (Source: Enhanced Outcome Surveillance) 5.6.4 Place of birth The overall proportion of treatment completion was significantly lower in cases that were non-UK born compared to cases that were born in the UK (72.1% vs. 85.6% P<0.001) if country of birth was known. The age distribution of tuberculosis cases that completed treatment was different according to the place of birth (median age: 59 years in cases born in the UK and 32 years in cases born abroad, figure 6). Figure 6: Age distribution of Tuberculosis cases that completed treatment (not including cases that have died or transferred out) according to place of birth 2001 – 2004 in the South West region (Source: Enhanced Outcome Surveillance)

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The chart and table (figure 7 and table 4) illustrates the proportions of treatment completions broken down by place of birth and age group Figure 7: Proportion of treatment completion (not including cases that have died or transferred out) among cases reported 2001 - 2004 by age group and place of birth in the South West region (Source: Enhanced Outcome Surveillance) Table 4 has been removed for the web version, complete version available on request. Pulmonary cases represented 55.7% UK born and 33.7% non UK born, whilst extra pulmonary cases represented 33.7% UK born and 58% non UK born (figure 8). Figure 8: Proportions of treatment completion (not including cases that have died or transferred out) broken down by pulmonary and extra-pulmonary cases and UK or Foreign born 2001 – 2004 in the South West region (Source: Enhanced Outcome Surveillance)

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5.6.5 Ethnic group The proportion of treatment completion varied by ethnic group (figure 9), with Black other and Bangladeshi ethnic groups having the lowest proportion of completion of treatment (40% and 50% respectively) with the Indian Sub Continent Other and White groups having the highest proportion of completion (100% and 82.2% respectively). Figure 9: Proportion of treatment completion (not including cases that have died or transferred out) among cases reported 2001 - 2004 by ethnic group, in the South West region (Source: Enhanced Outcome Surveillance) 5.7 Reasons for non-completion of treatment 5.7.1 Overall results Among the 151 cases having not completed treatment at one year, 35.1% had been lost to follow, 31.8% were reported as still on their initial course of treatment, 16.6% stopped their treatment, 15.9% were unknown or missing and 0.6% had not completed their treatment but no reason was given (figure 10). Figure 10: Reasons for non-completion of treatment (not including cases that have died or transferred out) among cases reported 2001 - 2004 in the South West Region (Source: Enhanced Outcome Surveillance) * No reason given for non completion

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Completed Treatment Not completed treatment


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5.7.2 Cases still on treatment Among the 48 cases who were still on treatment at one year between 2001 and 2004, 56.3% were still on their initially planned course of treatment, in 33.3% of cases the initial course of treatment had been changed and in 8.3% of cases the course of treatment had been interrupted. Information was missing in 2.1% (table 5). 56.3% of the cases (n=9) that had the initial course of treatment changed were due to a drug intolerance. 43.8% (n=7) had poor clinical response to treatment, 6.3% (n=1) had initial drug resistance and 6.3% (n=1) developed a new drug resistance. Of the 48 cases still on treatment, 2 cases were resistant to Isoniazid and 24 were sensitive, 1 case was resistant to rifampicin and 25 cases were sensitive and there were no cases of multi drug resistant TB (MDRTB).

2001-2004 Reason for still being on treatment %

Still on initially planned treatment 56.3 Treatment interrupted 8.3 Treatment changed 33.3 Missing information 2.1 Total 100

Table 5: Reasons for still being on treatment at one year among cases reported 2001-2004, in the South West region (Source: Enhanced Outcome Surveillance) 5.8 Reasons for non-completion of treatment according to case characteristics 5.8.1 Previous history of tuberculosis 9.8% (n=68) of cases had a previous history of TB, one year after starting treatment 22.1% of patients with a previous history had not completed treatment and 21.9% of patients with no previous diagnosis had not completed treatment. The proportion of cases that did not complete treatment due to treatment being stopped, patients still being on treatment or due to unknown reasons were higher in those cases that had a previous history of TB (figure 11). However, a higher proportion of cases with no previous tuberculosis history were reported to be lost to follow-up and not completed treatment without a reason given.


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Figure 11: Reasons for non-completion of treatment (not including cases that have died or transferred out) by history of previous tuberculosis among cases reported 2001 - 2004, in the South West region (Source: Enhanced Tuberculosis Surveillance) * No reason given for non completion 5.8.2 Site Overall, 22.5% of pulmonary cases had not completed treatment at one year compared to 20.7% of extra pulmonary cases. Among these, there was a higher proportion of non-completion of treatment due to being lost to follow up and treatment stopped in pulmonary cases (figure 12). Higher proportions of non-completion treatment due to still being on treatment and cases that were unknown/missing were observed in extra pulmonary cases. Figure 12: Reasons for non-completion of treatment (not including cases that have died or transferred out) by site of disease (pulmonary vs. extra pulmonary) among cases 2001 - 2004, in the South West region (Source: Enhanced Tuberculosis Surveillance) * No reason given for non completion ** Pulmonary with or without extra-pulmonary localisation *** Extra-pulmonary only

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5.8.3 Drug susceptibility testing results 2 cases had MDRTB during the period 2001-2004. Both cases occurred in Avon, were black African and born in Somalia. Both cases completed treatment. Excluding the MDRTB cases, 1 case was resistant to rifampicin; this case was still on treatment. Of the 24 cases that were resistant to Isoniazid, 50% had completed treatment and 29% were lost to follow up. 389 cases were sensitive to rifampicin and 366 cases were sensitive to Isoniazid. No cases were resistant to pyrazinamide or ethambutol. Tuberculosis cases with resistance to rifampicin or MDR tuberculosis should be treated for at least 18 months. Patients that had a resistance to any of the drugs used to treat TB had a lower treatment completion rate (51.9%) than the overall figure for 2001-2004 (78.1%) (figure 13). The main reason for non completion of treatment in patients that had a drug resistance was due to ‘lost to follow up’ (25.9%). This proportion was again higher than the overall figure for ‘lost to follow up’ (7.7%). 77.7% of tuberculosis patients with a resistance to any drug were foreign born. Figure 13: Outcome category (not including cases that have died or transferred out) by drug resistance among cases 2001 - 2004, in the South West region (Source: Enhanced Tuberculosis Surveillance)

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Any resistance (n=27)

Isoniazid resistance (n=26)


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5.9 Completion of the South West data The proportion of cases having completed a treatment outcome form according to the Health Protection Team was calculated for the seven teams for the period 2001-2004. The proportion varied from 100% in Dorset to 64.8% in Cornwall and Isles of Scilly. Of the outcomes returned the proportion that completed treatment (excluding deaths and cases that have transferred out) ranged from 95.5% in Cornwall and IOS to 61.8% in Somerset (figure 14). For the South West the overall proportion of completion treatment was 78.1% between 2001-2004.

Figure 14: Proportion of Outcomes returned and proportion of returns that completed treatment (not including cases that have died or transferred out) among cases reported 2001 - 2004 by Health Protection Team, in the South West region (Source: Enhanced Outcome Surveillance) Figure 15 demonstrates there is a small relationship between the proportion of treatment completion and the median age of tuberculosis cases. Avon HPT had the lowest median age of TB cases, Somerset had the highest median age.

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1020

304050

6070

8090

100

Avon

Cornwall

& IOS

Dorset

Glouce

stersh

ireDev

on

Somers

et

Wiltshir

e

Heatlth Protection Teams

Perc

enta

ge (%

)

% Outcomes Returned % Outcomes returned that Completed Treatment


21 HPA South West

Figure 15: Proportion of treatment completion (not including cases that have died or transferred out) among cases reported 2001 - 2004 by median age of tuberculosis cases and by Health Protection area, in the South West region (Source: Enhanced Outcome Surveillance) 5.9.1 Summary of outcome data for South West

Proportion of treatment completion Case characteristics

% Sex (n=688)

Male 77.0 Female 79.8

Age (years) (n=688) 0-9 90.9 10-19 64.3 20-29 69.4 30-39 78.6 40-49 84.5 50-59 81.6 60-69 81.8 70-79 77.9 80+ 82.0

Place of birth (n=614) UK born 85.6 Non UK born 72.1

Ethnic group (n=683) White 82.2 Black Caribbean 77.8 Black African 75.0 Black Other 40.0 Indian, Pakistani, Bangladeshi 69.2 Chinese 81.3 Other ethnic groups 77.6

Previous history of TB (n= 688) Previous TB 77.9 No previous TB 78.1

Site of disease (n=688) Pulmonary TB* 77.5 Extra-pulmonary TB** 79.3

Table 6: Summary of tuberculosis Treatment Outcome Surveillance for patients notified (not including cases that have died or transferred out) in the South West region 2001 - 2004 (Source: Enhanced Outcome Surveillance) *Pulmonary tuberculosis with or without extra-pulmonary localisation **Extra-pulmonary localisation only


22 HPA South West

6. Discussion The aim of tuberculosis surveillance both regionally and nationally is to provide information which can be acted upon to help in the prevention and control of tuberculosis. Good surveillance and treatment outcome surveillance at local, regional and national level is therefore essential. This is the first TB outcome surveillance report for the South West covering the years 2001-2004. The report provides information on 87% (n=786) of tuberculosis cases that reported an outcome between this period; the proportion of outcomes reported varied from 94.6% in 2002 to 74.3% in 2004. Nationally the proportion of cases for which treatment outcomes were reported increased from 79% to 88% between 2001 and 2003, but dropped slightly to 86% in 20043. The CMO’s National Action Plan for stopping tuberculosis recommends that 100% of patients diagnosed with tuberculosis have the outcome of their treatment recorded2. Within the South West the proportions of outcomes received varied considerably between Health Protection Teams; Dorset achieved 100% of outcomes returned for 2001-2004 closely followed by Gloucestershire and Wiltshire. Devon had the lowest proportion of outcomes received in 2001 and 2002, Cornwall and Isles of Scilly and Somerset had the lowest in 2003 and Cornwall and Isles of Scilly also had the lowest in 2004. Among the tuberculosis cases with an outcome reported between 2001 and 2004, 68.3% had completed treatment, ranging from 64.3% in 2002 to 70.2% in 2003. The proportion of cases completing treatment in the South West is lower than the national proportion which has remained stable at 78% and 79% between 2001 and 20043. The CMO’s National Action Plan for stopping tuberculosis recommends that at least 85 per cent of tuberculosis cases successfully complete their treatment2. The most common reason for non-completion of treatment was due to death (12.2%). Of the cases reporting a cause, 15.4% died as a direct result of tuberculosis. Where the relationship between TB and the cause of death was known, tuberculosis caused or contributed to 42.8% of reported deaths. It was decided to also analyse the treatment outcome data excluding cases that died (or were diagnosed through post mortem) and cases that transferred out, this is because these cases were not able to complete their year’s worth of treatment in the South West. Tuberculosis cases analysed excluding cases that died or transferred out cannot therefore be directly compared to the CMO’s recommendations. Excluding the cases that died and transferred out, 78.1% of cases completed treatment, this ranged from 79.5% in 2001 to 75.4% in 2002. The reasons for non-completion of treatment were 7.7% lost to follow up, 7.0% were still on treatment, 3.6% stopped treatment, 3.5% the outcome was unknown or missing and 0.1% the treatment was not completed (no reason given). The proportion of pulmonary cases that completed treatment was 77.5%; the proportion of extra pulmonary cases was 79.3%. Of the pulmonary culture confirmed cases, 8.8% were reported to be “cured”, this is lower than the national figure of 16.5% in 20011. Pulmonary cases represented 55.7% of UK born and 33.7% of non UK born, whilst extra pulmonary cases represented 33.7% UK born and 58% non UK born. 9.8% of cases had a previous history of tuberculosis. Subsequent analysis showed that there was no association between treatment completion and previous history of tuberculosis (77.9% vs. 78.1% P=0.981). Treatment completion was similar in males and in females (77% males vs.79.8% females P=0.385). There was significant variation in outcome by age, country of birth and geographical area of residence. The 0-9 age group had the highest proportion of treatment completed and the 10-19 age group had the lowest proportion, this is largely because most cases were still on treatment. Treatment completion was significantly lower in cases that were non-UK born compared to cases that were born in the UK (72.1% vs. 85.6% P<0.001). The median age of cases born in the UK was higher (59 years) compared to non-UK born (32 years). 2 cases had Multi Drug Resistant Tuberculosis (MDRTB), both of these cases were black African, born in Somalia and completed treatment. 24 cases were resistant to Isoniazid and 1 case was resistant to rifampicin. 77.7% of tuberculosis patients with a resistance to any drug were foreign born. Patients that had a resistance to any of the drugs used to treat TB had a lower treatment completion rate (51.9%) than the overall figure for 2001-2004.


23 HPA South West

Black other and Bangladeshi ethnic groups had the lowest proportions of completion of treatment (40% and 50% respectively), largely due to cases being lost to follow up. The Indian Sub Continent Other group and White groups had the highest proportion of completion (100% and 82.2% respectively). The proportion of tuberculosis cases that completed treatment (excluding deaths and cases that transferred out) varied by health protection teams, ranging from 61.8% in Somerset to 95.5% in Cornwall and IOS. Outcome status results should be interpreted with caution since the proportion of cases for which information on outcome status was missing between 2001 and 2004 was 13%. Using 12 months from the start of treatment, diagnosis or notification as a cut off to assess outcome may mask details of events occurring during the course of treatment (e.g. interruption) which may differ between subgroups of the population and between different areas. A better understanding of the final treatment outcome could be obtained by collecting the data at the end of the treatment1.


24 HPA South West

7. References

1. Tuberculosis Section, Centre for Infection, Health Protection Agency First Annual Report on Tuberculosis Treatment Outcome Surveillance in England, Wales and Northern Ireland. Outcomes Results on Tuberculosis cases reported in 2001. http://www.hpa.org.uk/infections/topics_az/tb/pdf/firstTOMTB2001.pdf

2. Stopping Tuberculosis in England – an Action Plan from the Chief Medical Officer. Gateway

reference:1176. 2004. London, Department of Health. http://www.dh.gov.uk/assetRoot/04/10/08/60/04100860.pdf

3. Focus on Tuberculosis: Annual surveillance report 2006 – England, Wales and Northern Ireland.

London: Health Protection Agency Centre for Infections. November 2006.


25 HPA South West

Health Protection Agency South West The Wheelhouse Bond’s Mill Stonehouse Gloucestershire GL10 3RF Tel: 01453 829740 Fax: 01453 829741 E-mail: [email protected]

[email protected]

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