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					Chapter Three



Respiratory Disease
What do we mean by respiratory disease
Respiratory diseases are the third main cause of mortality in Gwent, Wales and the
UK, after cardiovascular disease and cancers, and a major cause of both acute and
chronic ill-health. Diseases of the respiratory system are defined as ICD-9 460-519;
this chapter will focus on chronic obstructive airways disease (ICD-9 490-496), asthma
(ICD-9 493), pneumonia (ICD-9 480-486) and influenza (ICD-9 487). Respiratory
tract cancers are covered in the Cancers chapter, and Tuberculosis (TB) in the Report
of the Consultant in Communicable Disease Control.
Chronic Obstructive Airways Disease (COAD) affects mainly adults from middle
age onwards. It is more common in women than men, although large numbers of both
sexes are affected. Chronic bronchitis, emphysema and asthma are included in the
definition. The major cause of chronic bronchitis and emphysema is cigarette smoking
and preventive action to reduce smoking is described in the Healthy Living chapter.
In addition, COAD is associated with areas of socio-economic deprivation, and those
who have worked in certain industries. It is a major cause of morbidity and disability
in those affected.
Asthma affects all ages and both sexes. The commonest cause is thought to be a
combination of an inherited tendency to allergic disease and exposure to trigger factors
in the environment. The highest rates are in children and older adults. It is more
common in boys until the late teens, thereafter it is more common in women. World
wide there seems to have been an increase in prevalence over the last thirty years, and
the reasons for this are still unclear.
Pneumonia (infections of the lungs) affects predominantly young children, the elderly,
and those with reduced immunity to infection for any reason. It can be caused by a
variety of different organisms. There is an effective vaccine against ‘Pneumococal’
pneumonia, one of the commonest causes seen in the community.
Influenza (‘flu’) is a viral illness, usually occurring sporadically. It is usually self-
limiting in healthy people, but can cause serious morbidity in the elderly and those
with reduced immunity to infection. The influenza virus is constantly evolving, and
occasionally a strain emerges which causes epidemics, or even pandemics, such as that
of 1918-19. There is a vaccine available each year, based on expert consensus as to
which strains are likely to affect the UK in the following year.
Standardised mortality ratios (SMR) and rates of potential years of life lost (PYLL) for
all respiratory disease, COAD, asthma and pneumonia are shown to highlight
variations in respiratory mortality between Gwent and the localities. Mortality rates
have been standardised to account for differences in population structures, using the
rate calculator in Healthshow version 98.1, the Welsh Public Health Common Data



                                                                                      45
Set, 1997. SMRs for influenza are not shown due to the very small coded number of
deaths.
There are no routinely available data on morbidity from respiratory disease in Gwent.
1993 data from the GP Chronic Disease Management scheme are available for
practices in the old Gwent Family Health Services Authority (FHSA) area. These data
therefore exclude practices in the Rhymney valley. Comparison is made with the
prevalence of asthma based on UK data from the General Practice Research Database1.
Data on influenza and pneumococcal vaccination uptake have been collated from
computerised GP practice records.
Hospital activity data for 1995/96 to 1997/98 from PEDW have been used to calculate
crude (i.e. unstandardised) admission rates by locality for all respiratory disease,
COAD, pneumonia and asthma. Welsh Office Targets in the health gain area of
respiratory disease have been set for mortality from lung cancer and lifestyle targets
for smoking. These targets are covered in the Cancers and Healthy Living chapters.
Descriptive epidemiology: Who gets respiratory disease, how many
people are affected?
Mortality: deaths from respiratory disease
Tables 3.1 to 3.5 show the numbers of deaths from respiratory disease registered in the
five year period 1993 to 1997.
Table 3.1 All-respiratory disease: total numbers of deaths, 1993-97

                            0-4       5-14    15-24    25-44    45-64   65-74     75+

  Blaenau Gwent               6        1        1        8       68     205       579
  Caerphilly                  6        0        1       11       106    327       987
  Torfaen                     7        0        0        7       54     161       554
  Monmouthshire               1        1        0        6       31     114       523
  Newport                     4        1        1       11       66     227       745

  Gwent                      24        3        3       43       325    1034      3388

Source: Healthshow v98.1

Table 3.2 Chronic obstructive airways disease: total numbers of deaths, 1993-97

                            0-4       5-14    15-24    25-44    45-64   65-74     75+

  Blaenau Gwent               1        0        0        2       39     113       139
  Caerphilly                  0        0        0        6       71     194       310
  Torfaen                     1        0        0        1       30      86       116
  Monmouthshire               0        0        0        1       14      51       107
  Newport                     0        0        1        2       35     121       133

  Gwent                       2        0        1       12       189    565       805

Source: Healthshow v98.1



46
Table 3.3 Asthma: total numbers of deaths, 1993-97

                                 0-4      5-14         15-24    25-44         45-64     65-74          75+

  Caerphilly                      0         0           0         2            8            8          10
  Blaenau Gwent                   1         0           0         1            15           5            4
  Torfaen                         1         0           0         0            2            5            6
  Monmouthshire                   0         0           0         0            1            5            8
  Newport                         0         0           1         1            1            5          10

  Gwent                           2         0           1         4            27        28            38

Source: Healthshow v98.1




Table 3.4 Pneumonia: total numbers of deaths, 1993-97

                                 0-4      5-14         15-24    25-44         45-64     65-74          75+

  Caerphilly                      2         0           0         2            25       104            598
  Blaenau Gwent                   1         0           1         3            19        82            383
  Torfaen                         3         0           0         5            19        59            376
  Monmouthshire                   0         1           0         4            11        50            380
  Newport                         1         0           0         5            19        92            532

  Gwent                           7         1           1        19            93       387            2269

Source: Healthshow v98.1




Table 3.5 Summary table of deaths from respiratory diseases, 1993-97


                     All respiratory            COAD              Pneumonia                     Asthma

                     M     F          P   M      F          P   M       F           P   M         F          P

 Caerphilly         728    710    1438    341    240     581    316     415     731     9         19         28
 Blaenau Gwent      391    477    868     159    135     294    190     299     489     9         17         26
 Torfaen            382    401    763     140    94      234    199     263     462     2         12         14
 Monmouthshire      305    371    676     106    58      164    172     274     446     5         9          14
 Newport            471    584    1055    178    139     317    251     398     649     7         11         18

 Gwent              2777 2543 4820        924    666     1590 1128 1649 2777            32        68     100


Source: Healthshow v98.1




                                                                                                             47
Tables 3.6 to 3.8 show standardised mortality ratios (SMR) standardised to the Gwent
population for males and females <75 years averaged over the five year period 1993-
97. The SMR is the ratio of the observed numbers of death in an area to the numbers
of death expected if that area had the same population distribution as Gwent. Localities
with an SMR of over 100 have higher mortality than Gwent, localities with an SMR of
less than 100 have lower mortality; the tables annotate whether the difference is
statistically significant.

Table 3.6 Standardised mortality ratios: males age <75, 1993-97

  Cause of death     Blaenau Gwent       Caerphilly    Torfaen     Monmouthshire   Newport

  COAD                     139*             122*          102           58*          79*

  Asthma                   302*             116           63            31           41

  Pneumonia                142*              98           100           82           92

  All respiratory          142*             110           103           67*          84*
  * statistically significantly different from Gwent=100, p<0.05

Source: Healthshow v98.1

Table 3.7 Standardised mortality ratios: females age <75, 1997

  Cause of death     Blaenau Gwent       Caerphilly    Torfaen     Monmouthshire   Newport

  COAD                     162*             117           85            49*          89

  Asthma                   251*              88           87            75           58

  Pneumonia                171*              77           107           81           95

  All respiratory          161*             103           91            67*          91
  * statistically significantly different from Gwent=100, p<0.05

Source: Healthshow v98.1


Table 3.8 Standardised mortality ratios: persons age <75, 1993-97

  Cause of death     Blaenau Gwent       Caerphilly    Torfaen     Monmouthshire   Newport

  COAD                     150*             120           94           54*           84*

  Asthma                   270*              97           80            60           53

  Pneumonia                155*              89           103           82           93

  All respiratory          150*             107           98           67*           88*
  * statistically significantly different from Gwent=100, p<0.05

Source: Healthshow v98.1



48
Potential Years of Life Lost (PYLL) from a disease is a function of the numbers of
people dying of that disease and the age at which they die. PYLL up to the age of 75
are shown as five-year average 1993-97 rates per 100,000 potential years of life for
diseases of the respiratory system, COAD, and pneumonia, in figures 3.1 to 3.3 below.




      Figure 3.1 All respiratory disease: 1993-97



               25

               20

               15
        PYLL




               10

                5

                0
                    Gwent        Blaenau    Caerphilly    Torfaen    Mon’shire   Newport
                                  Gwent

                                           Male          Female


      Source: Healthshow v98.1



      Figure 3.2 All respiratory disease: 1993-97



               12
               10
                8
        PYLL




                6
                4
                2
                0
                    Gwent        Blaenau    Caerphilly     Torfaen   Mon’shire   Newport
                                  Gwent

                                           Male          Female


      Source: Healthshow v98.1




                                                                                           49
      Figure 3.3 Pneumonia: 1993-97



                        8
                        7
                        6
                        5
       PYLL




                        4
                        3
                        2
                        1
                        0
                            Gwent   Blaenau    Caerphilly   Torfaen    Mon’shire   Newport
                                     Gwent


                                              Male            Female

      Source: Healthshow v98.1


Morbidity: illness from respiratory disease
Asthma
The definition and diagnosis of asthma is not straightforward due to its wide clinical
spectrum and overlap with other respiratory conditions, such as bronchitis (ICD9 466)
in children and the whole spectrum of chronic airflow obstruction in adults (ICD9 490
- 497). This clearly causes difficulties in the interpretation and comparison of data
relating to asthma.
The 1993 Chronic Disease Management programme for the 84 general practices in old
Gwent estimated the mean prevalence of asthma as 6.2% + 3% for males and 5.9% +
2.7% for females. Figure 3.4 shows the considerable variation in reported practice
prevalence rates.

      Figure 3.4 Practice asthma prevalence: persons 0-74 years, Gwent 1993


                       16
                       14
                       12
        % prevalence




                       10
                        8
                        6
                        4
                        2
                        0
                                                 Practice

      Source: Gwent FHSA Chronic Disease Management Programme 1993



50
The age-sex breakdown is shown in figure 3.5 and shows a close agreement with
national asthma period prevalence rates per 1000 population estimated from the
General Practice Research Database 19961, shown in figure 3.6. Asthma was defined
as a diagnosis of asthma (ICD9 493) ever recorded and treatment with drugs
(bronchodilators, inhaled corticosteroids, cromoglycate and related therapy) in the
previous 12 months.
     Figure 3.5 Age specific asthma prevalence: old Gwent 1993

                       9
                       8
                       7
       % prevalence




                       6
                       5
                       4
                       3
                       2
                       1
                       0
                            0-14       15-19    20-24     25-44    45-64     65-74         Total

                                                 Age Group

                                                Male        Female

     Source: Gwent FHSA Chronic Disease Management Programme 1993

     Figure 3.6 Age-sex specific asthma prevalence rates: UK, 1996

                      14
                      12
                      10
       % prevalence




                       8
                       6
                       4
                       2
                       0
                           0-4     5-15 16-24 25-34 35-44 45-54 55-64 65-74 75-84    85+      All
                                                                                             ages
                                                 Age Group

                                                Male        Female

     Source: Gwent FHSA Chronic Disease Management Programme 1993

Chronic Obstructive Airways Disease
There are no local data routinely available on the incidence and prevalence of COAD.
However since COAD is closely related to smoking rates in the population and
industrial exposures; COAD morbidity, as with mortality, would be expected to be
higher in Blaenau Gwent and Caerphilly and lowest in Monmouthshire.



                                                                                                    51
Hospital activity data
Figures 3.7 to 3.10 show average crude total admission rates (deaths & discharges) per
1000 population for the three years 1995/96 to 1997/98, for all respiratory disease,
COAD, pneumonia and asthma. The general pattern shows as expected from the
established associations with socioeconomic deprivation, higher rates from Blaenau
Gwent and Caerphilly, and significantly lower rates in Monmouthshire for all
respiratory disease and its major component, COAD. No real patterns emerge for
pneumonia and asthma admissions: this may be accounted for by smaller numbers and
hence greater impact of coding misclassification and population age-sex differences.

      Figure 3.7 Crude admission rates per 1000 population:
      all-respiratory disease

                                            20
       Crude rate per 1000 population




                                            18
                                            16
                                            14
                                            12
                                            10
                                             8
                                             6
                                             4
                                             2
                                             0
                                                 Caerphilly   Blaenau   Torfaen   Mon’shire   Newport
                                                               Gwent

     Source: PEDW


      Figure 3.8 Crude admission rates per 1000 population: COAD

                                             6
           Crude rate per 1000 population




                                             5

                                             4

                                             3

                                             2

                                             1

                                             0
                                                 Caerphilly   Blaenau   Torfaen   Mon’shire   Newport
                                                               Gwent

      Source: PEDW



52
     Figure 3.9 Crude admission rates per 1000 population: pneumonia

                                        2.0
       Crude rate per 1000 population


                                        1.8
                                        1.6
                                        1.4
                                        1.2
                                        1.0
                                        0.8
                                        0.6
                                        0.4
                                        0.2
                                        0.0
                                              Caerphilly   Blaenau   Torfaen   Mon’shire   Newport
                                                            Gwent

     Source: PEDW


     Figure 3.10 Crude admission rates per 1000 population: asthma

                                        2.5
       Crude rate per 1000 population




                                         2


                                        1.5


                                         1


                                        0.5


                                         0
                                              Caerphilly   Blaenau   Torfaen   Mon’shire   Newport
                                                            Gwent

     Source: PEDW

Pneumonia and Influenza
A study undertaken in Gwent of the effectiveness of influenza immunisation policy
during the winter of 1994/952 found that fewer than 50% of high risk patients were
immunised, whilst 25% of all immunisations were given to patients at low risk - the
“worried well”. Most patients were immunised following opportunistic advice from
their GP or to a lesser extent their health visitor. A wide variation in practice
immunisation rates was found, shown in figure 3.11.




                                                                                                     53
      Figure 3.11 Influenza immunisation rates by practice, 1997


                      500

                      400
       % prevalence




                      300

                      200

                      100

                        0
                                        Practice

      Source: Gwent Health Authority

Overall in Gwent, 97 doses/1000 population were given - falling far short of the
estimated 150 doses/1000 required to implement the Chief Medical Officer’s advice
on immunising all aged 75 years of age and older and all patients in defined high risk
categories3, 4. Clearly the present ad-hoc approach to influenza immunisation falls short
of delivering an evidence-based public health policy aimed at reducing the impact of a
major epidemic cause of morbidity and mortality2.
Figure 3.12 shows cumulative data on pneumococcal immunisation from Gwent
practices 1994 to 1998. A huge variation from 0/1000 to 155/1000 practice population
(median 21/1000, inter-quartile range 3/1000 to 41/1000) is seen. Figure 3.13 shows
the mean pneumococcal immunisation rate per locality. Again, considerable variation
is seen. Blaenau Gwent has the highest mortality from respiratory disease, yet the
lowest immunisation rates. Overall, Gwent Health Authority has the lowest levels of
pneumococcal immunisation in Wales, figure 3.14.

      Figure 3.12 Cumulative practice pneumoccocal immunisation rates 1994-98


                      160
                      140
                      120
       % prevalence




                      100
                       80
                       60
                       40
                       20
                        0
                                        Practice

      Source: PIAS




54
Figure 3.13 Cumulative locality pneumoccocal immunisation rates 1994-98

                                 40

                                 35
 Doses per 1000 population




                                 30

                                 25

                                 20

                                 15

                                 10

                                  5

                                  0
                                      Caerphilly       Blaenau        Torfaen     Mon’shire      Newport
                                                        Gwent

Source: PIAS



Figure 3.14 Cumulative pneumococcal immunisation rates: Welsh Health
Authorities 1994-98

                                 60
     Doses per 1000 population




                                 50

                                 40

                                 30

                                 20

                                 10

                                  0
                                      Dyfed        North Wales    Welsh    Morgannwg   Bro Taf     Gwent
                                      Powys                      average
                                                                 Health Authority
Source: PIAS




                                                                                                           55
                     Health Needs Assessment: summary
 • Respiratory disease is the third major cause of mortality in Gwent and Wales,
   causing around 15% of all deaths at 1000 deaths per year
 • Cigarette smoking is a major aetiological factor
 • Mortality rates and potential years of life lost are strongly associated with
   social deprivation, being markedly higher in Blaenau Gwent and lower in
   Monmouthshire
 • Hospital admission rates for all-respiratory disease and COAD are significantly
   higher in Caerphilly and Blaenau Gwent, and lower in Monmouthshire
 • A systematic approach to the collection, validation and use of morbidity data
   from primary care would enhance our understanding of health needs
 • Influenza and pneumococcal vaccination rates show wide inter-practice
   variation. Pneumococcal vaccination rates are lowest in Blaenau Gwent where
   respiratory mortality rates are highest


                                Key Issues for Action
 • The overall burden of morbidity and mortality from respiratory disease and the
   variations between localities
 • To optimise the treatment of patients with chronic obstructive airways disease
   and asthma
 • To achieve 90% uptake of influenza and pneumococcal vaccines by vulnerable
   groups, especially those living in nursing and residential homes


Evidence Based Priorities for action in Respiratory disease:
The Health Evidence Bulletin: Respiratory diseases5 presents a systematic summary of
the evidence in this area found through a formal literature search across a wide range
of sources. The evidence has been critically appraised using internationally accepted
methods compiled into this technical document and subject to an internal and external
peer review process. Statements are provided with a precise indication of the strength
of the evidence and its sources. The bulletin is also available electronically, via the
NHS Cymruweb (http://cymruweb.wales.nhs.uk/pep) and the Internet
(http://www.uwcm.ac.uk/pep).
Smoking
Implementation of a Gwent wide tobacco control strategy, with emphasis on alliances
between the Health Authority and Local Authorities is discussed in the Healthy Living
chapter.



56
Chronic bronchitis and emphysema
Implementation of the British Thoracic Society guidelines for the management of
chronic obstructive airways disease6 throughout primary and secondary care in Gwent
will facilitate the delivery of high quality and standardised care to all patients. Two
particular elements of this care for which good evidence is available are domiciliary
oxygen for patients with severely hypoxaemic COAD and pulmonary rehabilitation.
There is survival benefit from at least 15 hours of oxygen per day7 in patients whose
PaO2 is less than 7.9 kilopascals (60 mm Hg). Patients with PaO2 less than 60mmHg
gain only small benefits (as measured by physiological function, exercise tests, and
quality of life)8. Pulmonary rehabilitation has been shown to be of short term benefit in
improving exercise tolerance and quality of life9.
Effective drug therapy5 includes inhaled bronchodilators (salbutamol, ipratropium and
salmeterol), oral theophylline in selected patients and antiobiotics in acute
exacerbations. The value of inhaled steroids and nebulisers is currently uncertain and
awaiting the outcome of further trials5.
Asthma
Implementation of the British Thoracic Society guidelines for the management of
asthma10 throughout primary and secondary care in Gwent will facilitate the delivery of
high quality and standardised care to all patients. This requires structured care within
general practice in appropriately trained nurse led clinics and regular medical review
through contracts for chronic disease management of asthma by GPs. These contracts
should be monitored to ensure that health professionals who are involved in the care of
asthmatics in the community such as practice nurses, are adequately trained and
supported and that the care provided is effectively monitored with reference to the
guidelines of the British Thoracic Society. Evidence-based guidelines for auditing the
long-term, primary care, monitoring of patients with asthma are available11.
The evidence for the effectiveness of drug therapies and delivery systems is reviewed
in the Respiratory diseases bulletin5.
Influenza and pneumococcal immunisation
Influenza immunisation has been shown to reduce the incidence of influenza and its
complications in all age-groups5, and to be the specific intervention most effective in
preventing pneumonia5. The Joint Committee on Vaccination and Immunisation12
recommends selective immunisation of high-risk groups (eg. people with diabetes or
chronic respiratory or renal conditions), residents of nursing homes, old people’s
homes and other long-stay facilities where rapid spread is likely to follow introduction
of infection.
Pneumococcal immunisation gives good protection against pneumococcal pneumonia
in low risk patients13 , patients with chronic cardiac or airways disease and asplenic
patients14. However one trial suggests no benefit in non-immunocompromised people
over 50 years old who have been previously treated in hospital for community-
acquired pneumonia15. Immunisation is currently recommended for those aged two
years or older in whom pneumococcal infection is likely to be more common and/or
dangerous and guidance is available12.



                                                                                      57
The wide variation in practice and locality immunisation rates demonstrate the need
for a systematic evidence-based preventive approach to increase immunisation rates in
all practices in Gwent, but particularly in Blaenau Gwent.
 The evidence-base for the management of chronic obstructive airways disease,
asthma, pneumonia and immunisation is clear. Gwent wide implementation of the
evidence should be enhanced: the Gwent-wide Respiratory New Local Strategies for
Health Group proposed the development of joint care programmes with primary care
to include guidelines for referral, investigation and treatment, shared care particularly
of chronic conditions, secondary prevention, rehabilitation, open access to appropriate
diagnostic services and clinics, and clinical audit.




58
References
1    Office for National Statistics. Key Health Statistics from General Practice 1996. Lomdon: Office
     for National Statistics, 1998.

2    Watkins J. Effectiveness of influenza vaccination policy at targeting patients at high risk of
     complications during winter 1994-5: cross sectional survey. British Medical Journal
     1997;315:1069-70.

3    Watkins J, Rogers C, Evans J. Who needs influenza vaccination? Estimating the size of the high
     risk population - implications of the introduction of age-based policies. Lancet 1998;353:208-9.

4    Department of Health. Influenza immunisation: extension of current policy to include all those
     aged 75 years and over. CMO (98) 15.

5    Health Evidence Bulletins. Health Evidence Bulletins - Wales: Respiratory Diseases. Cardiff:
     Welsh Office,1998.

6    The COAD Guidelines Group of the Standards of Care Committee of the British Thoracic Society.
     BTS guidelines for the management of chronic obstructive Airways disease. Thorax 1997; 52
     suppl.5.

7    Medical Research Council Working Party. Long term domiciliary oxygen therapy in chronic
     hypoxic cor pulmonale complicating chronic bronchitis and emphysema. Lancet 1981; i: 681-86.

8    McDonald CF, Blyth CM, Lazarus MD, Marschner I, Barter CE. Exertional oxygen of limited
     benefit in patients with chronic obstructive Airways disease and mild hypoxemia. American
     Journal of Respiratory and Critical Care Medicine 1995; 152: 1616-19.

9    Lacasse Y, Wong E, Guyatt GH, King D, Cook DJ, Goldstein RS. Meta-analysis of respiratory
     rehabilitation in chronic obstructive Airways disease. Lancet 1996; 348: 1115-19.

10   British Thoracic Society, The National Asthma Campaign and others. The British Guidelines on
     asthma management. 1995 review and position statement. Thorax 1997; 52 (suppl.1): S2-S21.

11   Eli Lilly National Clinical Audit Centre Monitoring asthma. University of Leicester, Department
     of General Practice: Eli Lilly National Clinical Audit Centre, 1994.

12   Salisbury DM, Begg NT (eds.) Immunisation against infectious disease. Department of Health and
     Others. London: HMSO, 1996.

13   Fine MJ, Smith MA, Carson CA et al. Efficacy of pneumococcal vaccination in adults: a meta-
     analysis of randomized controlled trials. Archives of Internal Medicine 1994; 154: 2666-77.

14   Butler JC, Breiman RF, Campbell JF et al. Pneumococcal polysaccharide vaccine efficiency. An
     evaluation of current recommendations. Journal of the American Medical Association 1993; 270
     (15): 1826-31.

15   Örtqvist Å, Hedlund J, Burman L-Å et al. Randomised controlled trial of 23-valent pneumococcal
     capsular polysaccharide vaccine in prevention of pneumonia in middle-aged and elderly people.
     Lancet 1998; 351: 399-403.




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