Gaps in use

Need by Māori for Pharmaceuticals, and Gaps in Use

Māori have known higher rates of premature death and disability than non-Māori across most health conditions. A large body of evidence indicates that significant disparities exist in life-expectancy and morbidity by ethnicity in New Zealand, with Māori and Pacific people more likely to die 10 years younger and be hospitalised more often for chronic conditions than other New Zealanders (Ajwani et al, 2003). Reasons for health disparities are likely to be complex, representing a mix of social, economic, behavioural, cultural and biological factors, of which the provision of pharmaceuticals is but one part.

Excess loss of disability adjusted life years (DALYs) borne by Māori compared with non-Māori (during the year 1996) has been most apparent for ischaemic heart disease (5000 excess DALYs), diabetes (4750 DALYs), chronic obstructive pulmonary disease (2000 DALYs), lung cancer (2000 DALYs), cardiovascular disease (1600 DALYs), lung cancer, suicide, and asthma. These features can be seen in figure 2 on the following page, which shows the extent of extra health need (rather than utilisation) for the Māori population, across the spectrum of diseases measured in the Ministry of Health’s NZ Burden of Disease Study (NZBDS). (Ministry of Health, 2001) (Figure 1).

Figure 1: Burden of disease in Māori – Excess loss of DALYs by Māori.

Overall, the 80,929 DALYs lost by Māori in 1996 accounted for 15% of all DALYs lost in New Zealand, but after adjusting for age Māori had rates two thirds higher than non-Māori (197.5 DALYs lost per 1000 population in Māori vs. 117.7 in non-Māori). These patterns are not expected to have changed substantially over the ten years since.

For conditions treatable/preventable by medicines on the Pharmaceutical Schedule, the above burden of disease data can be mapped to the above differences between Māori and non-Māori prescription rates. It is possible to map 85% of prescriptions to relevant NZBDS disease groups; in turn 85% of DALY loss appears to be for diseases treatable or preventable at least in part to medicines on the Pharmaceutical Schedule.

Provisional analysis of these mapped data has indicated that, despite Māori having higher prescription rates than non-Māori after adjusting for age, their prescription rates are still lower than they would appear to be in order to overcome their much greater disease burden in most areas. Overall, Māori have 615,058 fewer prescriptions than expected, being 19% lower would occur otherwise.

Leading gaps in Māori prescription volumes are for cardiovascular medicines including antifibrinolytics/antithrombotics, statins, and smoking cessation medicines (182,052 prescriptions below expectation) and antibacterials [relating to the NZBDS categories of bacterial infections (including septicaemia)] (142,840). Other gaps include:

By contrast, prescription rates are higher than expected for NSAIDS/gout/analgesics/muscle relaxants at 66,519 extra prescriptions, for reasons that require further elucidation (see graph):

Figure 2: Gaps in Māori use of medicines, after adjusting for age and burden of disease (need) relevant to the Pharmaceutical Schedule

Allied to lower rates of antipsychotic use, note that the use of antiparkinson agents is higher in Māori (1,117 extra prescriptions). It would be useful to analyse further by chemical these disparities to see whether patterns differ between newer antipsychotics and older antipsychotics (which are more liable to cause Parkinsonian and related movement side effects, requiring antiparkinson agents).6

Given these disparities one area that can be influenced by PHARMAC activities is that of access to and the use of medicines by Māori – where one quarter of Māori are likely to have unfilled prescriptions, being 40% higher than the non-filling rate for non-Māori aged 15+ (Ministry of Health, 2006).