Effects of the heavy usage of kava on physical health: summary of a pilot survey in an aboriginal community.
Health status was assessed in 39 kava users and 34 non-users in a coastal Aboriginal community in Arnhem Land. Twenty (27%) respondents were very heavy (mean consumption, 440 g/week) users of kava; 15 (21%) respondents were heavy (310 g/week) users of kava and four (5%) respondents were occasional (100 g/week) users of kava. Kava users were more likely to complain of poor health and a "puffy" face, and were more likely to have a typical scaly rash, and slightly-increased patellar reflexes. Very heavy users of kava were 20% underweight and their levels of gamma-glutamyl transferase were increased greatly. Albumin, plasma protein, urea and bilirubin levels were decreased in kava users, and high-density lipoprotein cholesterol levels were increased. Kava users were more likely to show haematuria, and to have urine which was poorly acidified and of low specific gravity. The use of kava was also associated with an increased red-cell volume, with a decreased platelet volume and with a decreased lymphocyte count. Shortness of breath in kava users was associated with tall P waves on a resting electrocardiogram, which provided suggestive evidence of pulmonary hypertension. In common with other Aboriginal communities, there was evidence of decreased lung volumes, a high carriage rate of hepatitis B surface antigen, and of other morbidity that was unrelated to the use of kava. On the basis of these findings, there is a strong rationale for urgent social action to improve health in Aboriginal communities and, in particular, to reduce the consumption of kava and to improve the nutritional status of kava users.