Age and Ageing 2001; 30: 155±159
#
2001, British Geriatrics Society
Dyspnoea and quality of life in older people at home S HU F. H O, M. S INEAD O'M AHONY, J OHN A. S TEWARD 1 , P ATRICIA B REAY , M AURICE B UCHALTER2 , M ICHAEL L. B URR3 University Department of Geriatric Medicine, 3rd Floor, Academic Centre, Llandough Hospital, Penlan Road, Penarth, South Glamorgan CF64 2XX, UK 1 Welsh Cancer Intelligence and Surveillance Unit, Cardiff, UK 2 Department of Cardiology, University Hospital of Wales, Cardiff, UK 3 Centre for Applied Public Health Medicine, Cardiff, UK Address correspondence to: M. S. O'Mahony. Fax: (q44) 29 20 711 267. Email:
[email protected]
Abstract Objectives: to determine the prevalence of dyspnoea in older people at home, measure its impact on function and quality of life, and identify associated cardio-respiratory diseases. Design: cross-sectional population-based study. Methods: we sent a modi®ed Medical Research Council (MRC) dyspnoea questionnaire to identify breathlessness in 1404 randomly selected subjects from general practitioner lists of 5002 subjects aged 70 years and over living at home. We visited a further random sample of 500 of these subjects at home and at a study centre. Setting: community-based study in South Wales. Main outcome measures: prevalence of dyspnoea (MRC grades 3±5) and its effect on psychological and functional status, and quality of life as measured by Hospital Anxiety and Depression, Nottingham Extended Activities of Daily Living and SF-36 questionnaires. Results: the prevalence of dyspnoea as de®ned was 32.3% (95% con®dence intervals: 30.3, 34.3). Breathless subjects had poorer functional status than non-breathless subjects. They also had poorer physical and mental health and were more likely to be anxious and depressed. The prevalence of left ventricular systolic dysfunction, reversible airways disease and obesity were all higher in those with dyspnoea. Conclusions: dyspnoea is common in older people. Given its profound adverse effect on people's lives, dyspnoea is an important public health issue. Keywords: activities of daily living, dyspnoea, older people, population study, quality of life
Introduction As functional status in¯uences everyday life, delaying the onset of dependency and disability is essential to improving health-related quality of life of older people [1, 2]. Whilst the importance of neuro-disability has been recognized, less attention has been paid to the disability associated with other common conditions affecting older people. In epidemiological studies of older populations, dyspnoea predicts both functional deterioration and mortality [3, 4], possibly because of its ability to predict cardiovascular death [5]. There are few data on dyspnoea and quality of life in older people at home. The reported prevalence of dyspnoea varies from 62% of people over 65 [6] to 16% of men of mean age 59 [4].
We determined the prevalence of dyspnoea and investigated its impact on functional status and quality of life in older people living at home. We examined the relative strengths of association between age, social class, sex, dyspnoea and functional status and quality of life, and identi®ed cardio-respiratory diseases associated with dyspnoea.
Methods We randomly selected 1404 subjects from general practice lists of 5002 subjects aged 70 and over living at home in the South Wales town of Barry. We excluded residents of care homes. The town has a population of 62 000, with an age and social class structure
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S. F. Ho et al. representative of the general population in England and Wales [7]. We sent a modi®ed Medical Research Council (MRC) dyspnoea scale to all subjects, followed by a second mailing and telephone call to non-responders. Of the responders, a strati®ed random sample of 250 breathless and 250 non-breathless subjects were visited at home by a research nurse. Subjects scoring -7 out of 10 on the abbreviated mini-mental test were excluded from further study. The remaining subjects completed interviewer-administered questionnaires to assess function and quality of life, and subsequently attended a centre for clinical assessment, pulmonary function tests, electrocardiography and echocardiography. This study was given ethical approval by Bro Taf local research ethics committee and we obtained written informed consent from all subjects.
The short form 36 (SF-36), a generic measure of health status, was administered by an interviewer in its amended form for use with older people [15, 16]. The scores were aggregated into physical and mental cumulative summary scores. Statistical analysis
Population prevalences were estimated as proportions, taking into account the random variation from twostage sampling and the ®nite population correction factor [17 ]. The STATA 6.0 survey module was used, with weightings to correct for the strati®cation by breathlessness category, to ensure that estimates of prevalence were all consistently based on the original population of 5002 [18]. The summary scales were expressed as a percentage of maximum. The effect of dyspnoea on quality of life and functional status was investigated using one-way analysis of variance [18].
Measurements We diagnosed reversible airways disease as 15% reversibility in FEV1 following 5 mg nebulized salbutamol, and chronic obstructive pulmonary disease as both FEV1 and the FEV1/FVC ratio being less than the lower limits of normal for older people [8]. Atrial ®brillation was diagnosed on electrocardiography. Left ventricular function was assessed by echocardiography, analysed by two of three independent observers. Global left ventricular function was assessed as normal or mildly, moderately or severely impaired. Disagreements between the observers were adjudicated by the third observer. The presence of arthritis, diabetes mellitus, previous strokes (including transient ischaemic attacks) and ischaemic heart disease ( history of angina or myocardial infarction) were determined by direct questioning of all subjects in the subsample. We de®ned obesity as a body mass index (BMI) of )30 kg /m2, overweight as a BMI of 25±29.9 kg/m2 and the normal range as BMI 18.5±24.9 kg/m2[9]. We administered the MRC dyspnoea scale both as a postal questionnaire and by interview [10]. Clinically signi®cant breathlessness was de®ned as MRC grades 3±5 (i.e. breathless when walking with other people his/her own age on level ground, or worse), as in other studies [4, 11]. We administered the Nottingham Extended Activities of Daily Living (NEADL) instrument [12, 13] to assess participation of 21 activities within four categories: mobility, kitchen, domestic and leisure activities. Each activity was scored 0 for `not done at all', 1 for `with help', 2 for `alone with dif®culty' or 3 for `with ease'. The Hospital Anxiety and Depression (HAD) scale consists of 14 items relating to the degree of distress experienced during the past week; 0 none, 1 a little, 2 a lot and 3 unbearable [14]. High overall scores (11q) indicate de®nite cases of anxiety or depression.
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Results Response rate
Of the 1404 subjects approached, 1169 (83%) responded. Of the non-responders to the ®rst mailing, 61 were found to be ineligible because of hospitalization, move to care homes or death. A random sample of the 174 non-responders to two mailings revealed that a further 52 subjects were ineligible, leaving 122 true non-responders. Of the estimated 1291 eligible cases in the sample, 1169 (91% of eligible) participated in the study. Four hundred and ®fty-two (90%) of the subsample of 500 were visited at home and completed the disability assessments. Of the 48 withdrawals, 15 were due to death, 10 to subjects having marked cognitive impairment, nine to subjects moving to care homes and 14 to refusal to participate further. A total of 425 subjects had full medical assessment including physical examination and spirometry. Of these, 358 had an electrocardiogram and 351 had an echocardiogram. Population prevalence of dyspnoea and other conditions
The population age and sex breakdown in this random sample was representative of the population over 70 years of age in Barry. The overall population prevalence of dyspnoea (MRC grades 3±5) was estimated as 32.3% (95% con®dence intervals: 30.3, 34.3); 27.6% in men and 35.4% in women (Table 1). The prevalence of dyspnoea increased with age in both men (P 0.006) and women (P 0.023). The population prevalence of self-reported arthritis was 34.2% (29.6, 42.9), self-reported stroke 7.7% (5.02, 10.37) and diabetes mellitus 8.25% (5.7, 11.35).
Dyspnoea and quality of life The population prevalence of obesity was 26.7% (22.4, 31.0). The agreement between the postal questionnaire and the interviewer-administered MRC respiratory questionnaire was high (P-0.0001). The sensitivity and speci®city of the postal questionnaire for identifying breathlessness in older people at home were 97 and 91%, with positive and negative predictive values of 91 and 97% respectively. Relationship between dyspnoea and psychological morbidity
There was a signi®cant difference between total HAD scores for dyspnoeic (mean 13.1) and non-dyspnoeic Table 1. Population dyspnoea
prevalence
of
self-reported
% of subjects (95% con®dence interval)
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Age, years
Men
70 74 75 79 80q All
19.2 26.9 45.3 27.6
Women
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
(11.0 (18.2 (29.3 (22.6
27.4) 35.6) 61.3) 32.6)
25.7 38.9 41.8 35.4
(17.8 (29.6 (32.2 (31.2
33.6) 48.3) 51.3) 39.6)
groups (mean 9.4; P-0.0001). This difference was similar in both the anxiety and depression subscales of the HAD: 62.4% of the dyspnoeic subjects were anxious and depressed (HAD score 011) compared with 36.4% of non-dyspnoeic subjects (P-0.0001). The results for the mental component of health-related quality of life were similar. The mean SF-36 mental cumulative summary score for dyspnoeic subjects was 50.8, which was signi®cantly lower than that for non-dyspnoeic subjects (mean 54.1; P-0.001).
Impact of dyspnoea on functional status and quality of life
There was a signi®cant relationship between dyspnoea and functional status, as shown by lower total NEADL scores in dyspnoeic subjects (mean 41.8) compared with those without dyspnoea (mean 52.5; P-0.0001). Breathless subjects scored signi®cantly lower than nonbreathless subjects in all four domains of NEADL (Table 2). Mobility tasks were the most discriminatory between the two groups. There were ceiling effects for kitchen tasks in that the scores were heavily skewed towards the top of the scale.
Table 2. Effects of breathlessness on domains of Nottingham Extended Activities of Daily Living index Score
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Mean (95% CI), by group
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Domain/item
Maximum
Mobility Do you (i) walk around outside?c (ii) climb stairs?c (iii) get in and out of the car?c (iv) walk over uneven ground?c (v) cross roads?c (vi) travel on public transport?c In the kitchen Do you (i) manage to feed yourself ? (ii) manage to make yourself a hot drink? (iii) take hot drinks from one room to another?b (iv) do the washing up? (v) make yourself a hot snack?b Domestic tasks Do you (i) manage your own money when you are out? (ii) wash small items of clothing?c (iii) do your own shopping?c (iv) do a full clothes wash?c Leisure activities Do you (i) read newspapers or books? (ii) use the telephone? (iii) write letters?a (iv) go out socially?c (v) manage your own garden?c (vi) drive a car?b
18
Dyspnoeic
Non-dyspnoeic
P value
9.8 (9.2, 10.5)
14.5 (13.8, 15.1)
-0.0001
15
13.8 (13.5, 14.2)
14.5 (14.2, 14.7)
-0.05
12
7.6 (7.1, 8.0)
10.2 (9.7, 10.6)
-0.0001
18
10.6 (10.1, 11.1)
13.3 (12.8, 13.8)
-0.0001
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
CI, con®dence interval. When each item of the index was examined separately, breathless subjects scored signi®cantly lower than non-breathless subjects in daily activities at the following levels of signi®cance: aP-0.05, bP-0.01, cP-0.0001 (Bonferroni correction for multiple testing was used).
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S. F. Ho et al. Using Bonferroni correction for multiple testing, dyspnoea still had a signi®cant effect on all six items of mobility. Within domestic tasks, dyspnoea had signi®cant effects on washing clothes and shopping but there was no effect on managing one's money when out (P 0.23). In leisure activities, dyspnoea had signi®cant negative effects on writing letters, going out socially, managing the garden and driving the car. There was no effect on reading newspapers or books (P 0.35), or using the telephone (P 0.31; Table 2). Breathless subjects also scored signi®cantly lower on the physical component of health-related quality of life, with a mean SF-36 physical cumulative summary score of 28.9, compared with 44.0 in the non-breathless (P-0.0001). Possible contributory factors to dyspnoea
The prevalence of breathlessness did not differ signi®cantly between social classes (P 0.2). Nor was there any relationship between breathlessness and smoking (P 0.99): breathlessness was reported by 28 (49%) of 57 current smokers, 84 (50%) of 168 ex-smokers and 113 (50%) of 226 lifelong non-smokers. The population prevalence of obesity (BMI )30 kg/m2) estimated from the subsample was 33.9% in dyspnoeic subjects and 23% in non-dyspnoeic subjects. On x2 test, there was a strong association between dyspnoea and obesity (P-0.05). In our study, 66.3% of obese subjects were breathless compared with 36% of non-overweight subjects (BMI-25). The prevalences of reversible airways disease, chronic obstructive pulmonary disease and left ventricular systolic dysfunction were all much higher among those with dyspnoea (Table 3). They were more likely to have at least one of these diseases than non-dyspnoeic subjects (46.1% versus 23.7%, P-0.0001).
Discussion We have identi®ed dyspnoea as a common problem in older people at home, affecting up to one-third of the population. Its impact on functional status and quality of life was substantial. On assessment of extended activities of daily living, mobility tasks were most affected. Domestic tasks and leisure activities were also impaired.
Some of these effects, particularly participation in leisure activities, may be related to underlying psychological morbidity, which was signi®cantly increased in dyspnoeic subjects as measured by the HAD scale. These ®ndings are consistent with other studies of respiratory diseases in older people, which reported social isolation, loneliness, anxiety and loss of self-esteem in patients with chronic respiratory conditions [19]. In a survey in 1992, 29% of people aged over 85 lived in residential care or continuing-care hospitals compared with 1.1% of those aged 65±74 years [20]. By excluding such patients, this study has underestimated the burden of morbidity in the total population. Self-reporting was used to identify those with stroke, diabetes mellitus and arthritis. This is appropriate for epidemiological studies but may underestimate the true prevalence of conditions [21]. There is also potential bias towards identifying those who have been in contact with the health services and who have received treatment, so that an unrepresentative sample is selected. Our ®ndings are broadly consistent with those of the General Household Survey in 1976 [22], which reported chest problems to be the second most common cause of severe disability in older people at home (after musculoskeletal disorders). In our study, both dyspnoea and arthritis were common and dyspnoea had striking effects on quality of life and function, as measured by SF-36, NEADL and HAD. Dyspnoea was associated with reversible airways disease (P-0.009), chronic obstructive pulmonary disease (P-0.0001), left ventricular systolic dysfunction (P-0.001) and obesity (P-0.05). Surprisingly, an association between smoking and dyspnoea was not found. This does not imply that smoking is not a risk factor for cardio-respiratory disease in older people. Associations between risk factors and disease can be distorted or even lost in cross-sectional studies, particularly in older populations. Most of our subjects were either non-smokers or ex-smokers, and we may have identi®ed a group with relatively low susceptibility to the effects of smoking, who have survived to old age. Our results indicate the potential for intervention at several levels. First, identifying and treating cardiorespiratory diseases needs to be a priority in ageing populations. Secondly, the relationship between obesity
Table 3. Population prevalence of clinically diagnosed conditions estimated from the subsample % of subjects (95% con®dence interval), by group
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Clinically diagnosed condition
Dyspnoeic
Non-dyspnoeic
P value of difference
Reversible airways disease Chronic obstructive pulmonary disease Atrial ®brillation Left ventricular systolic dysfunction Obesity
19.3 19.3 9.1 17.1 33.9
10.3 (6.2,13.3) 7.5 (4.0, 11.1) 7.1 (3.4, 10.9) 6.04 (2.6, 9.5) 23.0 (17.3, 28.7)
0.009 0.0001 0.48 0.001 0.01
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
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(14.0, 24.7) (14.0, 24.7) (4.9, 13.4) (11.4, 22.9) (27.6, 40.4)
Dyspnoea and quality of life and dyspnoea was striking and indicates a need to target health education programmes at this sector of the population. Finally, we have identi®ed clear needs in relation to daily function and quality of life in dyspnoeic subjects, particularly with mobility, social and leisure activities. Interventions targeted at these areas have the potential to reduce both the handicap and disability associated with the symptom of dyspnoea [23].
Key points
. Breathlessness in older people is an important public
health issue.
. One in three people aged over 70 who live in their
homes become breathless when walking on level ground with people of their own age. . This breathlessness is associated with obesity, chronic obstructive pulmonary disease, reversible airways disease and left ventricular dysfunction. . Breathlessness is associated with signi®cant impairments in function and quality of life.
Acknowledgements This study was funded by the Welsh Scheme for the Development of Health and Social Research (Grant no. RM 939/1). We are grateful to the general practitioners, medical receptionists, practice managers, patients, staff in the lung function and cardiology departments in Llandough Hospital, Cardiff, for their generous help.
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Received 7 July 1999; accepted in revised form 25 September 2000; final version received 2 October 2000
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