Avoidable Hospitalisation Introduction Avoidable hospitalisation is used to measure the occurrence of a severe illness that theoretically could have been avoided by either; Ambulatory sensitive hospitalisation (ASH) - Primary care interventions such as early detection and treatment or immunisation Preventable hospitalisation (PH) - Health promotion strategies such as smoking reduction. Population avoidable hospitalisation profile In 2005 there were 74,516 hospital discharges attributable to Auckland DHB residents. However, only 15 percent (11,245) were counted as avoidable according to the categories above. This was 16 percent (11,245 / 68,516) of total hospital discharges for those aged under 75 years. Figure (72) shows the percentage of the avoidable discharges for all the DHBs and the total for New Zealand, lower percentages are better. Auckland avoidable discharge percent was similar to the national rate. Figure (72) Avoidable discharges percent, all the DHBs, 2005
Trend and comparison The Auckland avoidable discharge rate in 2005 was 32.7 per 1000 population. It ranked sixth among all DHBs. The lowest avoidable discharge rate of 9 per 1000 population was reported in Whanganui DHB (WAGDHB) and the highest rate of 48.5 per 1000 population was in Tairawhiti DHB (TRAWDHB). Figure (71) Avoidable hospitalisation rates per 1000 population, all DHBs, 2005 There was a steady decline in the trend of the number of hospital discharges categorised as unavoidable shown, however, there was no major changes in the trend of avoidable hospitalisation in figure (73) covering the period 2001-2005. However, there were slight decreases in both the avoidable and unavoidable discharges case weights shown in Figure (74). This confirms the previous picture shown in the general hospital discharges analysis. Figure (73) Avoidable and unavoidable hospitalisations, Auckland DHB, 2001-2005
Figure (74) Avoidable and unavoidable hospitalisations, Auckland DHB, 2001-2005
To ensure the comparability between the years, age standardised rates were calculated and shown in Figure (75). There were very minimal decline in the avoidable discharge rate. However, the decline in the unavoidable discharges was consistent. This is difficult to interpret, but could be explained by the redistribution of work between different provider sectors (ACC covered, insurance, private, etc) and warrants further investigation. Figure (75) Avoidable and unavoidable age-standardised hospitalisations, Auckland DHB, 2001-2005 Figure (76) shows that most of the reduction in case weights was among the unavoidable hospital discharges. However, there were some declines with avoidable discharges case weights this time. Figure (76) Avoidable and unavoidable case-weighted age-standardised discharge rates, Auckland DHB, 2001-2005
Figure (77) shows, when avoidable discharges are disaggregated into the two categories (ASH & PH), ASH were slightly decreasing, in contrast to the PH which shows no changes. Figure (77) Ambulatory Sensitive and Preventable age-standardised hospitalisations, Auckland DHB, 2001-2005
Variation by age Table (1) shows the distribution of the avoidable hospitalisation by age group. Most of the avoidable hospitalisations occurred at both extremes of life. Specifically, hospitalisations amenable to primary care had occurred at both extremes of life whereas conditions amenable to public health measures were mostly in older age groups. Table (1) Avoidable hospitalisation (ASH & PH) as a (number and age specific rate), Auckland DHB by age group, 2005 Variation by Gender
Figure (78) shows ASH and PH rate trends, 2001-2005, for both genders. ASH rate for both genders were similar around 30 per 1000 population and the trend show very minimum declines between 2001 and 2005. However, the PH for both genders was very much lower than the ASH. The PH for male gender was slightly higher than the female rate. There were no major changes for the PH in the trends for the study period. Figure (78) Avoidable hospitalisation (ASH & PH) rate, ADHB population, 2001-2005 Table (2) shows the detailed analysis for both ASH and PH by gender in 2005 for Auckland DHB as a number and rate. In general, as also seen in the graph above, the females have slightly lower ASH rates, with a risks ration Female/male of 0.88. However, for PH the difference between females and males was smaller and the risk ratio was 0.90. Table (2) Avoidable hospitalisation (ASH & PH Number & Rate) ADHB, 2005
Variation by Ethnicity There was no much change in ASH and PH rates by ethnicity, as shown in figure (79). Pacific people s ASH was the highest, followed by Maori, both ethnic groups had nearly double the rate of Non Maori Non Pacific, at 51/1000, 50/1000 and 25/1000 respectively. However, the PH for both Maori and Pacific people was similar with rate of around 7/1000 population, again nearly double the rate of Non Maori Non Pacific at 3/1000. Figure (79) Avoidable hospitalisation (ASH & PH) rates by ethnicity, Auckland DHB, 2001-2005 Table (4) shows the detailed analysis of avoidable hospitalisation by ethnicity.
Table (4) Avoidable hospitalisation (ASH & PH) discharges (number, rate and percent), by ethnicity, Auckland DHB, 2005 Variation by Socioeconomic status Table (5) shows the number and rate of avoidable hospitalisation by socioeconomic status. Both ASH and PH were increasing with higher socioeconomic deprivation. People living in the most deprived areas had the highest avoidable hospitalisation. Table (5) Avoidable hospitalisation (ASH & PH) discharges (number, rate and percent), by socio-economic status, Auckland DHB, 2005 Age standardised rate trends for both ASH and PH by deprivation level are shown in figure (80). The rates were lower for people living in areas of lower socioeconomic deprivation, and decreasing. Both ASH and PH were higher in people living in the most deprived areas. However, all the avoidable rates were decreasing for people living in most, medium and the least deprived areas. Figure (80) Age standardised avoidable hospitalisation by socio-economic status, 2001-2005
Variation by Cause With age there was a clear shift in hospital avoidable morbidity (ASH & PH) from the acute infections in the young, to the chronic debilitating conditions in older ages. Table (6) Top six avoidable hospitalisation conditions (Number & Percent) by age group, Auckland DHB, 2005
Variation by Gender and cause Table (6) shows the top ten avoidable conditions (ASH & PH) admitted to hospital in 2005 by patient gender. Table (7) Top ten avoidable hospitalisation conditions (Number / ASH & PH) by gender, Auckland DHB, 2005
Variation by Ethnicity and Cause Figure (83) shows the top ten avoidable conditions (ASH & PH) as a number and percent admitted to hospital in 2005 by patient ethnicity. The top avoidable conditions amenable to primary care for both Maori and Pacific people were gastroenteritis and diabetes. However, for Non Maori Non pacific the top condition amenable to primary care was ischemic heart disease. Figure (83) Top ten avoidable hospitalisation conditions (number & percent / ASH & PH) by ethnicity, Auckland DHB, 2005
Variation by Socio-economic Status and Cause Nine conditions amenable to primary care prevention were the same with different priority positions regardless the socioeconomic status. However, all the top ten
conditions amenable to public health measures were the same across the entire socioeconomic gradient, but again in a different order. Figure (89) Top ten avoidable hospitalisation conditions (number & percent / ASH & PH) by socioeconomic status, Auckland DHB, 2005
Table (8) shows the avoidable morbidity age standardised rate by gender and ethnicity for prioritisation purposes. Table (8) Age standardised avoidable conditions (ASH & PH) by ethnicity and gender, Auckland DHB, 2005