Longitudinal respiratory studies in older people

Prevalence and underlying causes of dyspnoea in older people: a systematic review

BACKGROUND

chronic dyspnoea is common in older people and is often of cardiac or pulmonary aetiology. Information on the exact prevalence and distribution of underlying causes is scarce. Our aim was to review the literature on prevalence and underlying causes of dyspnoea in the older population.

METHODS

two MEDLINE searches were conducted: the first on studies on the prevalence of dyspnoea in older persons aged ≥65 years using the Medical Research Council (MRC) dyspnoea scale and the second on the underlying causes of dyspnoea in this population. Quality assessment was performed for all included studies. Random effects models based on the logit transformed prevalences were used to calculate pooled prevalence with 95% confidence intervals (95% CI).

RESULTS

a total of 21 articles from 20 different populations reported the prevalence in the general older population with a median sample size of 600 (Interquartile range 262-1289). The pooled prevalence was 36% (95% CI: 27-47%) for an MRC of ≥2, 16% (95% CI: 12-21%) for an MRC of ≥3 and 4% (95% CI: 2-9%) for an MRC of ≥4. Prevalence rates were higher in women than in men. Only one article investigated the underlying causes of dyspnoea in older persons; in 70% of these patients, the dyspnoea was considered to be of cardiac or pulmonary origin.

CONCLUSION

dyspnoea is very common in older people, but estimates vary considerably between studies. Only one study describes the underlying causes.

Relation between respiratory symptoms, pulmonary function and peak flow variability in adults

BACKGROUND

A study was carried out to determine whether subjects with respiratory symptoms are more likely to have impaired lung function or increased airway lability, and to quantify these relationships in a population of adults.

METHODS

Data were collected from 511 participants (aged 20-70 years) from the Dutch part of the European Community Respiratory Health Survey (ECRHS). The symptoms analysed were: wheeze, dyspnoea > or = grade 3, nocturnal dyspnoea, cough and phlegm, and history of allergy. Lung function was measured by peak expiratory flow (PEF) and forced expiratory volume in one second (FEV1). PEF variability was used as an index for bronchial lability.

RESULTS

Both FEV1 and PEF were decreased with increasing numbers of symptoms. Subjects with one symptom had an increased risk of having an FEV1 value of < 70% (OR = 4.2) and this risk increased with an increasing number of symptoms. Subjects with three or more symptoms had an increased risk of having a PEF value of < 70%, a diurnal variation in PEF of > 10% (both OR = 4.4), and an increased risk of high between day variation (OR = 6.6).

CONCLUSIONS

Subject-reported symptoms are related to impaired lung function and to increased variability of peak flow.

Biological meaning of the prospective epidemiological study on chronic obstructive lung disease and aging

An epidemiological follow-up study on the occurrence of the chronic obstructive lung disease (COLD) in the elderly was carried out in a probability sample of Cracow inhabitants. The research dealt with defining the high risk groups. The health status of the population studied was appraised by standardized interviews and spirometric measurements. Prevalence of COLD was rather strongly related to age both in men and in women but the increase with age was not uniform, being linear below 50 yr and steep in older age groups. The logistic curve appeared to fit quite well to the empirical data regarding the frequency of COLD in relation to age. The overall relative risk of developing COLD estimated by odds ratio was also affected greatly by smoking and by respiratory symptoms. Against expectations, the study showed that the elderly run a substantial risk of developing COLD even without any respiratory symptoms and being a non-smoker. The data obtained indicate that age groups above 50 yr are more vulnerable as the pace of lung function deterioration is much higher than in younger persons. The changes produced by relatively mild pulmonary symptoms like productive cough adding to pre-existing changes caused by aging may precipitate definite chronic obstructive lung disease.