Respiratory Morbidity in General Practice, 1971-1991. 96/3

Download this Factsheet as a PDF

Introduction

Nationwide studies were carried out to record consultations with general practitioners in 1971-72, 1981-82 and in 1991-92. This factsheet looks at trends in respiratory morbidity over the three surveys. Information on the data is given in the footnote.

Changes in patient consultation rates

In 1971-2, 66% of the population registered with a doctor consulted at least once during the year. This increased to 71% in 1981-82 and to 78% in 1991-2. However, these increases may reflect increasing contact between doctors and patients, due to a shift towards more community-based care, the introduction of screening and a decrease in hospital follow-up for less serious conditions.

In all three surveys, diseases of the respiratory system were the most common reason for visiting a doctor. The percentage of patients who consulted for respiratory disease in each survey was 26%, 27% and 31% respectively. The major respiratory diseases for which patients consult are asthma, acute bronchitis & bronchiolitis, upper respiratory tract infections, chronic obstructive lung diseases (chronic bronchitis, emphysema and chronic airways obstruction) and allergic rhinitis (including hay fever).

Asthma

Figure 1:Patients consulting a GP for asthma, males and females.

The changes over time in patient consultation rates for asthma are shown in figure 1. It is clear that a large increase has taken place, most markedly between 1981 and 1991. In the 1971 survey, 1% of patients consulted for asthma during the year of study. In 1981 the figure was 1.8% and in 1991, 4.3%. In 1971, patient consultation rates were similar across the age-groups, but by 1991 there were larger variations by age-group. Although increases are seen in all age groups, it is most marked in the youngest children (ages 0-4), where the rate increased seven fold between 1971 and 1991. Reasons for these changes may include increasing prevalence and severity of asthma, changes in the balance between primary and secondary care, changes in therapy and management practice, and increased concern about asthma, especially among parents of young children. Diagnostic transfer over time from acute bronchitis and bronchiolitis is unlikely as consultation rates for these conditions also show an increase. However, asthma may more commonly have been applied as a label for symptoms and signs in more recent years.

Chronic obstructive lung disease

This group of diseases includes chronic bronchitis, emphysema and chronic airways obstruction, the third being as new diagnostic category not used in the 1971-72 survey of GP consultations. The changes in patient consulting rates are shown in figure 2.

Figure 2:Patients consulting a GP for chronic obstructive lung diseases

Although there has been little change overall, there has been a decrease in consulting rates in adults aged 45-64, and an increase in those ages over 75. Within this group of diseases, it is likely that diagnostic transfer has occurred from chronic bronchitis to chronic airways obstruction, as has been seen with death certification (LAIA factsheet 92/1). It is unlikely that substantial net diagnostic transfer has occurred away from asthma in the elderly as consultation rates for asthma have also increased in this age-group. However, some of the decline in rates of consultation for chronic obstructive lung diseases in younger age-groups may reflect increased use of asthma as a diagnostic label.

Acute bronchitis & bronchiolitis

Figure 3:Patients consulting a GP for acute bronchitis &bronchiolitus

This figure shows the changes in patient consultation rates for acute bronchitis & bronchiolitis. Rates overall were similar in 1971 and 1981, with a small increase in 1991. Among children, rates increased slightly in those aged 0-4, and decreased in the 5-14 age-group. Larger increases can be seen in the elderly, especially among those aged 75+ where rates almost doubled between 1971 and 1991.

Upper respiratory tract infections

Acute upper respiratory tract infections such as the common cold, sinusitis, tonsillitis and otitis media are the commonest respiratory complaints seen in general practice.

Figure 4:Patients consulting a GP for upper respiratory tract infections

Overall patient consultation rates were similar in the three surveys, the percentage of patients who consulted being 20%, 21% and 23%. The highest consultation rates are seen among the youngest children (ages 0-4). In this age-group, 56% consulted in 1971, compared with 67% in 1981 and 70% in 1991. These respiratory infections also account for a sizeable proportion of all consultations with doctors - around 9% of all consultations in each of the three surveys.

Hay fever and allergic rhinitis

Figure 5:Patients consulting a GP for hay fever/allergic rhinitis

The percentage of patients consulting their doctor for hay fever and allergic rhinitis increased from 1.1% in 1971, to 2.0% in 1981 and 2.8% in 1991. In all three surveys, the highest rates are seen in older children and young adults, although the largest relative increases in patient consultation rates have occurred in the elderly.

Summary

• The percentage of patients who visit their general practitioner in the course of a year has risen over the last twenty years.

• Respiratory diseases are the commonest reason for consultation with a family doctor.

• There has been a marked increase in the percentage of patients who have consulted their doctor for asthma. This has been most noticeable in children.

• Upper respiratory tract infections are the commonest respiratory complaint seen in General Practice.

Footnote

Definitions
Results from the studies are published as rates per 10,000 person-years at risk, which take into account patients moving into or out of the study practices during the study period. The data presented throughout this factsheet are patient consulting rates. This is based on the number of patients who consulted their doctor at least once during the study period, and can be thought of as a measure of the period prevalence. Data not presented in this factsheet are the total number of consultations with a doctor and the rate of new or first ever episodes. The total number of consultations is based on the number of consultations rather than the number of patients and gives an indication of the work-load associated with a particular condition or group of conditions. The latter could be used as a measure of the incidence of a particular disease.