The link between major risk factors and important categories of admission in an ageing cohort.

BACKGROUND: Record linkage of routine hospital data to population-based research findings presents an opportunity to explore the relationships between classical risk factors and hospital activity. METHODS: The objectives of this study were to examine, in Paisley and Renfrew, the effect of risk factor variables on the likelihood of experiencing an acute hospital admission with six major medical conditions. The subjects were 8,349 women and 7,057 men, aged 45-64 in the early to mid-1970s. The main outcome measures were acute hospital admission with principal diagnosis of: any malignant neoplasm; malignant neoplasm of trachea, bronchus and lung; ischaemic heart disease; respiratory disease; cerebrovascular disease; or diabetes mellitus. RESULTS: Smokers were almost eight times more likely to be admitted with lung cancer and, to a lesser extent, were more likely to be admitted for the other conditions investigated with the exception of diabetes mellitus. Forced expiratory volume was also an independent risk factor for admission with lung cancer and strokes. Higher levels of cholesterol were associated with increased risk of admission with ischaemic heart disease but less with cancer (including lung cancer). With the exception of admissions for cerebrovascular disease, deprivation category was found to have no independent effect on the likelihood of experiencing any of the morbidity outcomes examined. CONCLUSIONS: These data confirm that associations first established between risk factors and mortality outcomes (e.g. smoking and lung cancer) are also found between risk factors and hospital admissions for the same causes. This in itself is unremarkable, but the results are of interest for three reasons. First, they illustrate the potential of record linkage to map the effects of risk factors. Second, they demonstrate the size of the effect risk factors have on the risk of admission. Third, they provide a surprising finding that deprivation category does not act as an independent risk factor for the majority of the categories of admission investigated.

Influence of biological, behavioural, health service and social risk factors on the trend towards more frequent.

OBJECTIVES: To analyse the trend in rising acute hospital admission rates in the Renfrew Paisley MIDSPAN cohort and assess the influence of baseline risk factor data, morbidity patterns, deprivation category and characteristics of GP practice on the increase. DESIGN: Cohort analysis which, using a linked data set covering a 23 year follow-up period, combined original 'risk'-related data with subsequent routine hospital admissions data. A multiple logistic regression model predicted changes in hospital admissions patterns. SETTING: Renfrew and Paisley, two post-industrial towns in Scotland. SUBJECTS: Eight thousand three hundred and fifty four women and 7,052 men, aged 45-64 in the early 1970s. MAIN OUTCOME MEASURES: The contribution that each of the factors investigated made to the likelihood of admission over time. RESULTS: While risk status in middle life, diagnosis reached after admission, deprivation category and characteristics of GP practice influence the absolute chance of being admitted to hospital, changes in these factors do not explain much, if any, of the quite marked increase in admission rates observed during the last 10 year of the follow-up period. CONCLUSIONS: Whatever the reasons for the trend of rising admission, the most likely explanation appears to be a combination of social and health service related factors. For the Paisley-Renfrew cohort, factors like smoking status, FEV1, deprivation category and GP practice remain important predictors of admission throughout the time period but changes in these factors explain little of the rising trend in admissions.

Hospital use by an ageing cohort: an investigation into the association between biological, behavioural and social risk markers and subsequent hospital utilization.

BACKGROUND: The aims of the study were to describe the pattern of hospital utilization (acute and mental health sectors) of the Paisley-Renfrew MIDSPAN cohort and assess the influence of biological, behavioural and social 'risk factors' (established at the time of screening) on subsequent hospital admissions. METHOD: A cohort analysis was carried out in Paisley and Renfrew, two post-industrial towns in West Central Scotland. This used a linked data set covering a 23 year follow-up period to combine original 'risk'-related data with subsequent routine hospital admissions data. The subjects were 8349 women and 7057 men, aged 45-64 in the early to mid-1970s, and representing approximately 80 per cent of the eligible population. The main outcome measures were patterns of hospital utilization (acute and mental health sectors), 'any acute hospital admission', 'a serious acute hospital admission' and 'death' (relative risks of each outcome were calculated for all risk factors). RESULTS: The following patterns of hospital utilization were found. Only 5 per cent experienced a mental health admission but mean stay was long (265 bed days per cohort member admitted). In contrast, 79 per cent experienced at least one acute hospital stay. The age-specific proportions of cohort members requiring admission increased over time but the growth in acute episodes was even higher (suggesting increasing rates of multiple admission). For non-survivors, 42 per cent of all acute episodes (55 per cent of bed days) took place during the 12 months before death. Analysis of risk factors (using Cox's proportional hazards model) of 'any admission' and 'a serious admission' showed forced expiratory volume (FEV1), age, sex, smoking status, blood pressure, blood sugar, body mass index, cholesterol and deprivation category to be important predictors. CONCLUSIONS: Despite the desirability of alternative settings of care for the chronically ill and dying, a high proportion of hospital bed days were required near the time of death. The absolute size of the demand for hospital services within the cohort was strikingly large and increasing over time. Strategies to address the tide of rising admissions will have to confront the increasing proportion of individuals requiring admission as well as the growth in multiple admissions. Those who were at higher risk of admission were the older members of the cohort (especially men), those with low FEV1, smokers, those who were underweight or obese, the small number with abnormal levels of blood sugar, those with high blood pressure and those who lived in the most deprived areas. Thus, programmes which affect these determinants of ill health may be useful in reducing age-specific admission rates.

Immunoglobulin synthesis by salivary gland lymphoid cells in Sjögren's syndrome.

The synthesis of immunoglobulins by cells infiltrating the labial salivary glands has been studied by radioimmunoelectrophoresis in 20 patients with Sjögren's syndrome (SS) and in 14 control patients with related disorders. The patients with SS were producing significantly greater quantities of IgG, IgM, and IgA. Synthesis of IgG and IgM correlated with the degree of lymphoid infiltration but not with serum immunoglobulin concentration. Patients with SS and rheumatoid arthritis (RA) showed greater synthesis of IgG and IgM than those with uncomplicated RA. The only extensive lymphoid infiltration was seen in patients with SS. One patient with SS and primary macroglobulinemia was synthesizing the paraprotein in the lip biopsy as well as in the bone marrow. These results establish the immunologic competence of the infiltrating lymphoid cells and suggest their origin from an extrasalivary source.