Māori Health Review Issue 2

PREDICT-CVD is an opportunistic cardiovascular risk assessment and management programme. This study compared the cardiovascular disease risk factor status and risk management of Mäori with non-Mäori using data from over 20,000 PREDICT-CVD assessments carried out between 2002 and 2006. The population assessed comprised 1,450 (7%) Mäori and 19,164 non-Mäori (93%). At assessment, Mäori were an average of 3 years younger than non-Mäori. Compared to non-Mäori, Mäori patients had higher rates of cardio- vascular risk factors including smoking and diabetes. Blood pressure and TC/HDL levels were also higher in Mäori patients. Mäori with a history of CVD were more likely to receive medications including anticoagulants, blood pressure-lowering and lipid-lowering drugs. However revascularisation procedures were 50% less likely to be received by Mäori compared to non-Mäori with a history of ischaemic heart disease.

Around 50% of adult Mäori in New Zealand are smokers, as compared to around 20% of European New Zealanders. This randomised, placebo-controlled trial assessed the efficacy of bupropion as an intervention for smoking cessation in 134 Mäori smokers (> 10 cigarettes/day) aged 16-70 years. Continued abstinence from smoking at 3 and 12 months were the primary outcome measures. At 3 months, continued abstinence was higher with bupropion (44.3%) than placebo (17.4%), RR 2.54 (95% CI 1.30-5.00). At 12 months abstinence rates were 21.6 and 10.9% for the bupropion and placebo groups respectively, RR 1.99 (95% CI 0.79 to 5.00). In conclusion, the authors suggest that bupropion is an effective treatment for smoking cessation in the indigenous Mäori population in New Zealand.

This comprehensive report from the Ministry of Health details cancer findings, including disparities in incidence and outcomes between Mäori and non-Mäori for the period 1996 to 2001. Mäori ethnicity was classified using the ‘ever Mäori’ approach. Mäori were 18% more likely to be diagnosed with cancer than non-Mäori, and were almost twice as likely to die from their illness. Mäori were less likely to have their cancer stage recorded at diagnosis, and with regard to breast, lung, colon, rectum, cervix, prostate, testis, kidney, oral cancers and melanoma were more likely to be diagnosed at a later stage of the illness. The only cancer which was detected earlier in Mäori was stomach cancer. In general, Mäori have lower rates of survival for cancers. Some, but not all of this disparity may be related to the later detection of the cancers. In conclusion, the report finds; “the existence of stark disparities in experiences and outcomes of cancer between Mäori and non-Mäori” which indicates the need for “urgent and committed action” to address these issues.

Mäori are less likely to use cardiovascular rehabilitation services than other ethnicities, despite far greater rates of cardiovascular morbidity and mortality. The authors report on the first 6-months of a specialist mobile cardiovascular rehabilitation service provided by Te Kohao Health and based on Kirikiriroa marae. Data were collected from clinical and support assessment tools, client case notes, minutes from meetings and kanohi ki te kanohi (face to face) discussions with staff. Mäori referred to the service presented with complex socioeconomic and socio-cultural issues. In general Mäori accessing the service were younger than comparable Pakeha. Retention rates were higher for this service than for other cardiovascular rehabilitation services. The authors suggest that the success of this service may be as a result of providing a multi-faceted approach addressing the need for cultural support combined with clinical services.

This nationally-representative, face-to-face survey examined aspects of high frequency mental disorders including mood disorders, anxiety disorders, and alcohol and drug abuse disorders. A version of the Composite International Diagnostic Interview (CIDI 3.0), amended for use in the World Health Organisation, World Mental Health Survey Initiative was used. This report presented the data from over 2500 Mäori surveyed. Prevalence of mental disorders was high for Mäori (12-month prevalence 29.5%). Severity was described as moderate or severe for 75% of illnesses occurring in the past 12 months. High rates of co-morbid mental and chronic physical disorders were also described. Rates of significant suicidal thinking (3.8 %), suicidal plans (1.3%) and suicide attempts (0.7%) were significant. However uptake of specific health or other services was low.

This was a multi-stage study of Mäori patient experiences and perceptions with regard to health, disability and ACC services. Thematic analysis of data collected from 10 nationwide hui was used to develop a model of Mäori patient interactions with healthcare providers. This led to the creation of an ‘experiences of care’ survey tool which was used in a telephone survey of 651 Mäori. Many Mäori have concerns about interactions with health services and the cultural competence of providers, although most rated their most recent experience as generally good. A cluster analysis found two distinct groups of respondents. Those of younger age (78%) were more likely to report positive experiences with service providers, whilst the older age-group (22%) were less likely to consider returning again. The authors suggest that this may be explained by factors such as; “poor experiences in health or other services, expectations of lesser quality care and barriers such as a lack of cultural fit between the patient and provider.”

National total, acute and elective caesarean section (CS) rates (as proportions of women giving birth in New Zealand hospitals during 1997-2001) were used to examine relationships between CS, deprivation and ethnicity. Logistic regression analysis was used to adjust for age, deprivation, some clinical factors, and District Health Board. In comparison to Mäori, total, acute and elective rates of CS were significantly higher in non-Mäori women (21 vs 13%; OR 1.59; p < 0.0001 for total CS). Increasing deprivation was correlated with decreasing rates of CS. Differences between Mäori and non-Mäori remained after controlling for age, deprivation and other factors. The authors concluded that although deprivation may contribute to the differences observed, it does not fully explain them, and suggest that further research is warranted.

This report examines the scientific evidence behind the recent controversial claim by Lea and colleagues (see below for a link to the on-line abstract) that the low activity variant of the monoamine oxidase-A (MAO-A) gene was strongly associated with risk-taking and aggressive behaviour in Mäori. The MAO-A gene is believed to be important for the correct regulation of dopamine and serotonin levels, via the production of the MAO-A enzyme which breaks down both neurotransmitters. The high activity gene variant (found in 65% of Caucasians) has up to a 10-fold greater activity than the low activity variant, and may therefore be more effective in removing excess dopamine and serotonin. In MAO-A deficient mice (which lack the enzyme entirely), dopamine and serotonin levels are increased and aggressive behaviours have been observed. The term “warrior gene” was first coined following a small, un-replicated experiment using Rhesus macaque monkeys. No evidence for an association between genotype alone and aggressive behavior was found in this study, and aggressive behaviour could be predicted by both low and high-activity gene variants under different environmental conditions. In the three largest population-based studies in humans (all in Caucasians) the results were all similar and suggested the high-activity MAO-A variant may be protective against adult anti-social behavior for children who were abused or neglected. The low-activity variant did not predict aggressive behaviour unless these additional environmental factors were also considered. The study presented by Lea et al. was conducted in a very small (n = 17) sample of Mäori males. They found the low-activity MAO-A variant present in 60% of subjects, and called it the “warrior allele”, suggesting it was strongly associated with risk taking and aggressive behaviour in Mäori males. The authors of the current report, dispute this finding, citing a lack of scientific rigour and an absence of appropriate genetic epidemiological experiments testing for an association. They also point to evidence of racial variation between genetic associations indicating that results from a Caucasian population should not be extrapolated to Mäori.

In this article, the authors summarise their concerns with regard to the veracity and ethics of the “warrior gene” line of research. They raise concerns with regard to the informed consent process. In line with ethical principals of research, all participants should have been advised that the research included the exploration of hypotheses linking the “warrior gene” with violent and antisocial behaviour, and that results may be extrapolated from the research participants to the larger Mäori population despite the lack of evidence for association between the two. The authors ask questions about the scientific validity of an approach which has extrapolated from a small, likely non-random sample of Mäori males to not only the entire contemporary male Mäori population, but also to past generations. They also point to a lack of any association between genotype alone and anti-social behaviour from previous research and the risks of making a claim of causality on the evidence of association alone. Finally, the authors highlight the issue of skewed reporting and hype by the media, and comment that; “In such highly charged social and political settings, the scientist has a particular responsibility for the way in which findings are disseminated and for ensuring a clear public understanding of the limitations of the work to date.”