Health effects of kava use in an eastern Arnhem Land Aboriginal community

Abstract

Background: Heavy kava use in Aboriginal communities has been linked to various health effects, including anecdotes of sudden cardiac deaths. Aims: To examine associations between kava use and potential health effects. Methods: A cross-sectional study was carried out within a kava-using east Arnhem Land Aboriginal community in tropical northern Australia. One-hundred-and-one adults who were current, recent or non-users of kava were enrolled in March 2000. Main outcome measures were physical, anthropometric, biochemical, haematological, immunological and neurocognitive assessments. Results: Kava users more frequently showed a characteristic dermopathy (P < 0.001). They had increased levels of γ-glutamyl transferase and alkaline phosphatase (P < 0.001). Lymphocyte counts were significantly lower in kava users (P < 0.001). Fibrinogen, plasminogen activator inhibitor-1 and neurocognitive tests were not different between kava use categories. IgE and IgG antibodies were elevated across the whole group, as were C-reactive protein and homocysteine. Conclusions: Kava use was associated with dermopathy, liver function abnormalities and decreased lymphocytes. If kava continues to be used by Aboriginal populations, monitoring should focus on the health consequences of these findings, including a possible increase in serious infections. The interaction between kava, alcohol and other substances requires further study. Although markers of cardiovascular risk are increased across the population, these were not higher in kava users, and this increase may be linked to the large infectious pathogen burden reflective of the socioeconomic disadvantage seen in many remote Aboriginal communities. (Intern Med J 2003; 33: 336-340)

Kava use, dyslipidaemia and biomarkers of dietary quality in Aboriginal people in Arnhem Land in the Northern Territory (NT), Australia

“…Psychosocial factors are plausible causal agents for loss of body fat and are further indicated in Aboriginal Australian kava drinkers. For example, some Arnhem Land aboriginal people have used kava continuously for up to 18 y (Clough et al, 2003) and unpublished participants' observations suggest that drinkers even constrain their eating in order to maximise kava's mood-altering effects. Therefore, notwithstanding possible economic deprivation and appetite suppression in kava users, an obsession with kava drinking may be a significant contributing factor.…”

“…Self-reported kava consumption was confirmed by knowledgeable Aboriginal health workers and documentary evidence. Details of the study setting, methods for assessing exposure to kava and other substance use (alcohol, tobacco, and cannabis), and ethical approvals are described elsewhere (Clough et al, 2003). Participants gave written informed consent with procedures explained by health workers.…”

“…Per cent body fat was measured using a Tanita Body Fat (TBF 521) instrument. Plasma samples (nonfasting) were analysed for lipids (Clough et al, 2003), carotenoids and micronutrients (Rowley et al, 2001).…”

“…A possible association between heavy kava use and sudden death in Aboriginal Australians is an unresolved concern (Young et al, 1999). While clinical observation suggests that sudden deaths have occurred in Arnhem Land among heavy kava users, no clear evidence for increased risk of ischaemic heart disease was found in a recent case-control study (unpublished data) or of atherogenesis in a crosssectional study (Clough et al, 2003). Poor nutrition, which contributes to high rates of coronary heart disease (CHD) in Aboriginal Australians (Thomson, 1991;Rowley et al, 2001), may add to this concern.…”

“…In a recent study, continuing kava users were compared with less regular users and a group of nonusers. Lower body mass index (BMI), higher total cholesterol and a tendency for higher HDL-cholesterol were found in kava users, while other CHD risk markers (C-reactive protein and homocysteine) were generally elevated (Clough et al, 2003).…”