Posible colisión entre principios fundamentales

Preventable hospitalisation refers to emergency hospital admissions that can be prevented by timely and effective provision of primary care. This is an important indicator of primary care access and quality that is widely used in the international literature.9899, 100 In England, data from 2001 to 2013 showed that preventable hospitalisations make up one in every five hospital admissions, and have increased by 48% in the last 12 years.101 Common causes of preventable hospitalisations include urinary tract infection / pyelonephritis, pneumonia, chronic obstructive pulmonary disease (COPD), convulsions and epilepsy, and ear, nose and throat infections. Studies suggest that preventable hospitalisation can be reduced by

improving primary care supply and quality.102 These hospital visits not only result in poor outcomes, but also result in increased cost to the health care system.103 For instance, a recent study concluded that better management of patients in primary care could save £1.42 billion in England by reducing preventable hospitalisation.104 Similar cost estimates have been published for other countries.105106 Studies have also found that preventable hospitalisations are associated with the socioeconomic status of patients.107108

Our indicator evaluates socioeconomic inequality in preventable hospitalisation between small area populations from 2001/2 to 2013/14. We defined preventable hospitalisation as the proportion of people with an emergency admission for a chronic ambulatory care sensitive condition – admissions that are potentially avoidable if these chronic conditions are appropriately managed in primary care.109 This indicator could also be described as "emergency hospitalisation sensitive to primary care". We depart from the corresponding NHS Outcomes Framework definition by defining the indicator numerator as the number of people with one or more events, rather than the number of events. This is because (a) we have a separate measure of repeat hospitalisation and so want to focus this measure on the incidence of hospitalisation (the proportion of people hospitalised) rather than the intensity (how many times each individual is hospitalised); and (b) following advice from the two lay members of our advisory group, we believe that members of the public find it slightly easier to understand and relate to proportions (e.g. ‘x people per 1,000’ or ‘a chance of x in 100’) than event rates. We focused on chronic rather than acute ambulatory care sensitive

conditions, as the former are likely to be more sensitive to changes in primary care supply and quality. We used the same list of chronic ambulatory care sensitive conditions as the NHS Outcomes Framework (Indicator 2.3i). Our definition of preventable hospitalisation

uses all ages in both numerator and denominator, as does the NHS OF definition. However, the international OECD definition only includes age 15+, i.e. we include children but the OECD definition does not. We then indirectly standardised each year of data for age and sex at LSOA level. Further technical details of the standardisation procedure are in Chapter 4 Methods, and further indicator definition details are presented in Appendix 1.

Figure 27 Matrix plot showing unadjusted trends in preventable hospitalisation by age, sex and deprivation (fixed axes for comparisons across age groups)

Figure 28 Matrix plot showing unadjusted trends in preventable hospitalisation by age, sex and deprivation (free axes for comparisons across deprivation groups)

Figure 32 Caterpillar plot of the absolute gradient index of inequality in preventable hospitalisation in 2011/12 at CCG level

Figure 33 Scatter plots of CCG performance on preventable hospitalisation in 2011/12 against deprivation, showing both mean performance and equity performance (absolute gradient index)

There has been a slight fall in preventable hospitalisation over the study period, though substantial inequality persisted throughout. Looking at the age-sex breakdowns in the matrix plot in figure 28, the main exception to this trend was in children age 5-15 within the most deprived quintile group for whom preventable hospitalisation rose during the 2000s. The unadjusted trends show improvement in inequality in terms of SII and RII. However, this is misleading due to disproportionate ageing of the affluent population which is associated with a higher rate of hospitalisation in this quintile group. After age adjustment, the pro-rich trend disappears for both SII and RII. This inequality is seen both between CCGs and within CCGs as depicted by the correlation plots. Inequality lines up closely with deprivation, as shown by decile points on the scatter plot which all lie along the social gradient line. The caterpillar plot shows there are substantial numbers of CCGs performing significantly better and worse than the national average in terms of the absolute gradient index of inequality.

In the unadjusted trends, which do not allow for age and sex, both the SII and RII decline (get better) over time. This difference compared with the adjusted trends is due to demographic change over time: affluent neighbourhoods aged during the 2000s, while there was an increase in younger populations in deprived neighbourhoods. This demographic shift increased preventable hospitalisation in richer neighbourhoods relative to poorer

neighbourhoods and hence reduced pro-rich inequality in the unadjusted trends. We think the age-sex adjusted trends give a more accurate picture of NHS equity performance, on the basis that the NHS should not receive credit for an apparent reduction in pro-rich inequality

resulting from demographic change largely outside the control of the NHS.

A final point to note is the uptick in preventable hospitalisation in 2003/4, which was

particularly strong in the two most deprived quintile groups. The cause of this is not known. However, one speculation is that this may be related to change in the supply of GP out of hours care. This uptick in preventable emergency hospitalisation happened around the time of the introduction of the new GP contract which, among other things, allowed GPs to opt out of providing “out of hours” cover for emergency care outside normal GP practice working hours. This speculation may be worth exploring in future “quasi experimental” studies.