- Email: [email protected]
Hyperkalaemia and apple juice
CORRESPONDENCE
vegetables and the risk of acute ischaemic stroke.3 The consumption of one daily serving of a citrus juice is reported to lower the risk of acute ischaemic stroke by 25%, compared with 11% with all juices combined.3 Diets containing rich sources of potassium and low sodium are also recommended in international consensus hypertension treatment guidelines. On Oct 30, 2000, the US Food and Drug Administration allowed orange juice manufacturers to add a new health claim informing consumers that diets containing foods that are good sources of potassium and low in sodium may reduce the risk of high blood pressure and stroke. Foods that contain at least 10% of the daily value for potassium (3500 mg) and less than 140 mg sodium per serving are eligible for this claim.4 On the basis of these new labelling claims, mass marketing campaigns are underway by orange juice manufacturers to promote the health benefits of their juices and to encourage regular consumption of these products.5 Current US regulations for the labelling of food products do not require that potassium content be included. Avoidance of potassium from alternative medicine products such as noni juice can be made more difficult since potassium content is frequently not disclosed on the product labelling and also unavailable from traditional nutritional references. Furthermore, patients who have chronic renal disease might be enticed to use more of these products than healthy people if conventional medicine does not work. On the basis of this marketing push, more cases of hyperkalaemia from dietary causes might arise. These reported cases of hyperkalaemia illustrate the importance of close questioning of patients about the ingestion of juices and nutritional supplements with high potassium content. *Kevin M Sowinski, Bruce A Mueller *Department of Pharmacy Practice, School of Pharmacy and Pharmacal Sciences, Purdue University, D711 Myers Building, WHS, 1001 West 10th Street, Indianapolis and West Lafayette, IN 46202, USA; and Division of Clinical Sciences, College of Pharmacy, University of Michigan, Ann Arbor, MN (e-mail: [email protected]) 1
2
3
Williams E, Fulop M. A puzzling case of hyperkalaemia. Lancet 2001; 357: 1176. Mueller BA, Scott MK, Sowinski KM, Prag KA. Noni juice (Morinda citrifolia): hidden potential for hyperkalemia? Am J Kidney Dis 2000; 35: 310–12. Joshipura KJ, Ascherio A, Manson JE, et al. Fruit and vegetable intake in relation to risk of ischemic stroke. JAMA 1999; 282: 1233–39.
842
4
5
Health claim notification for potassium containing foods. http://www.cfsan.fda.gov/~dms/hclm-k.html (accessed May 31, 2001). Tropicana puts the squeeze on high blood pressure and stroke. http://www.tropicana. com/HealthNews/TropicanaSqueezes.asp (accessed May 31, 2001)
Author’s reply Sir—P Jarman and colleagues’ points about the occurrence of hyperkalaemia and Kevin Sowinski and Bruce Mueller’s report of a patient’s noni juice ingestion, have important implications about how to approach patients with apparently unexplained hyperkalaemia. Jarman and colleagues note that hyperkalaemia was more common than expected among the patients in their diabetes clinic, even those who were not taking antikaliuretic drugs and had no serious renal disease. They could identify no relation between contemporaneous serum glucose and potassium, and only slight association between haemoglobin A1 and potassium. However, in view of insulin’s important effect on the distribution of potassium between cell and extracellular fluids,1 it would be interesting to know how many of their hyperkalaemic patients with diabetes had insulin deficiency. Jarman and colleagues report that the mean serum potassium in their patients who were taking insulin did not differ significantly from those who did not, but insulin use doesn’t necessarily signify insulin deficiency. Information about the relations between serum potassium and aldosterone in patients with diabetes and in controls without overt renal disease would be useful. One wonders whether a mild degree of hypoaldosteronism might precede overt renal disease in patients with diabetes. When we unexpectedly find hyperkalaemia, or some other perplexing abnormality, we should remember that patients might not inform us fully about their diets and habits, either inadvertently or deliberately. That, and the foregoing cases and presented examples emphasise the importance of questioning patients in detail about their dietary habits, use of herbal and other alternative medicines, and food supplements, as well as medications. Milford Fulop Department of Medicine, Jacobi Medical Centre and Albert Einstein College of Medicine, New York, NY 10461, USA 1
Cox M, Stems RH, Singer I. The defense against hyperkalemia: the roles of insulin and aldosterone. N Engl J Med 1978; 299: 525–32.
Sex and gender matter Sir—Your May 12 news item by Michael McCarthy1 adds to the increasing number of publications about sex matters and men’s health;2 is this reporting the beginning of a paradigm shift? Although the emergence of new focus areas do not necessarily indicate a paradigm shift in which each new paradigm replaces the last, there seems to be a resurgence of men’s health issues at the forefront, together with or in place of women’s health policy and promotion. Men and women’s health have gained widespread attention in popular magazines, television shows, and in the wellness industry. Not surprisingly, there have been many calls to close the gap between men and women in longevity and illness experience. Reports by WHO clearly advocate the importance of a gender perspective to assist in understanding ageing and health, and stress the importance of research in clinical science and public health acknowledging gender differences.3,4 The Canadian report The health divide: how the sexes differ discusses life expectancy and reasons behind differences between women and men.2 To comment on the European experience, the differences in life expectancy are striking. In eastern European countries, especially in Russia, the gap is not 6 years, as reported for Canada, but closer to 10 years. In 2000, the WHO report suggested a 77% increased risk of premature death for Russian men between 1987 and 1994. With life expectancy, the gap between the sexes generally decreases as average life expectancy increases. Russia has one of the lowest life expectancies and, therefore, the widest gaps between sexes in healthy life expectancy in the world (66·4 vs 56·1 years for men compared with women).3 Undoubtedly, we must identify men as a high-risk group for premature death in this population. In 1999, the Institute of Social Medicine prepared a scientific report on men’s health for the Viennese government, to offer the health system a basis on which to identify focal points on men’s health issues.5 We concluded that men need to be specifically addressed as a target group for prevention campaigns and that their health can be significantly improved. Not only must appropriate primary and secondary prevention measures be taken, but support for gender-specific research and dissemination or translation of the results into health-care
THE LANCET • Vol 358 • September 8, 2001
For personal use. Only reproduce with permission from The Lancet Publishing Group.
vegetables and the risk of acute ischaemic stroke.3 The consumption of one daily serving of a citrus juice is reported to lower the risk of acute ischaemic stroke by 25%, compared with 11% with all juices combined.3 Diets containing rich sources of potassium and low sodium are also recommended in international consensus hypertension treatment guidelines. On Oct 30, 2000, the US Food and Drug Administration allowed orange juice manufacturers to add a new health claim informing consumers that diets containing foods that are good sources of potassium and low in sodium may reduce the risk of high blood pressure and stroke. Foods that contain at least 10% of the daily value for potassium (3500 mg) and less than 140 mg sodium per serving are eligible for this claim.4 On the basis of these new labelling claims, mass marketing campaigns are underway by orange juice manufacturers to promote the health benefits of their juices and to encourage regular consumption of these products.5 Current US regulations for the labelling of food products do not require that potassium content be included. Avoidance of potassium from alternative medicine products such as noni juice can be made more difficult since potassium content is frequently not disclosed on the product labelling and also unavailable from traditional nutritional references. Furthermore, patients who have chronic renal disease might be enticed to use more of these products than healthy people if conventional medicine does not work. On the basis of this marketing push, more cases of hyperkalaemia from dietary causes might arise. These reported cases of hyperkalaemia illustrate the importance of close questioning of patients about the ingestion of juices and nutritional supplements with high potassium content. *Kevin M Sowinski, Bruce A Mueller *Department of Pharmacy Practice, School of Pharmacy and Pharmacal Sciences, Purdue University, D711 Myers Building, WHS, 1001 West 10th Street, Indianapolis and West Lafayette, IN 46202, USA; and Division of Clinical Sciences, College of Pharmacy, University of Michigan, Ann Arbor, MN (e-mail: [email protected]) 1
2
3
Williams E, Fulop M. A puzzling case of hyperkalaemia. Lancet 2001; 357: 1176. Mueller BA, Scott MK, Sowinski KM, Prag KA. Noni juice (Morinda citrifolia): hidden potential for hyperkalemia? Am J Kidney Dis 2000; 35: 310–12. Joshipura KJ, Ascherio A, Manson JE, et al. Fruit and vegetable intake in relation to risk of ischemic stroke. JAMA 1999; 282: 1233–39.
842
4
5
Health claim notification for potassium containing foods. http://www.cfsan.fda.gov/~dms/hclm-k.html (accessed May 31, 2001). Tropicana puts the squeeze on high blood pressure and stroke. http://www.tropicana. com/HealthNews/TropicanaSqueezes.asp (accessed May 31, 2001)
Author’s reply Sir—P Jarman and colleagues’ points about the occurrence of hyperkalaemia and Kevin Sowinski and Bruce Mueller’s report of a patient’s noni juice ingestion, have important implications about how to approach patients with apparently unexplained hyperkalaemia. Jarman and colleagues note that hyperkalaemia was more common than expected among the patients in their diabetes clinic, even those who were not taking antikaliuretic drugs and had no serious renal disease. They could identify no relation between contemporaneous serum glucose and potassium, and only slight association between haemoglobin A1 and potassium. However, in view of insulin’s important effect on the distribution of potassium between cell and extracellular fluids,1 it would be interesting to know how many of their hyperkalaemic patients with diabetes had insulin deficiency. Jarman and colleagues report that the mean serum potassium in their patients who were taking insulin did not differ significantly from those who did not, but insulin use doesn’t necessarily signify insulin deficiency. Information about the relations between serum potassium and aldosterone in patients with diabetes and in controls without overt renal disease would be useful. One wonders whether a mild degree of hypoaldosteronism might precede overt renal disease in patients with diabetes. When we unexpectedly find hyperkalaemia, or some other perplexing abnormality, we should remember that patients might not inform us fully about their diets and habits, either inadvertently or deliberately. That, and the foregoing cases and presented examples emphasise the importance of questioning patients in detail about their dietary habits, use of herbal and other alternative medicines, and food supplements, as well as medications. Milford Fulop Department of Medicine, Jacobi Medical Centre and Albert Einstein College of Medicine, New York, NY 10461, USA 1
Cox M, Stems RH, Singer I. The defense against hyperkalemia: the roles of insulin and aldosterone. N Engl J Med 1978; 299: 525–32.
Sex and gender matter Sir—Your May 12 news item by Michael McCarthy1 adds to the increasing number of publications about sex matters and men’s health;2 is this reporting the beginning of a paradigm shift? Although the emergence of new focus areas do not necessarily indicate a paradigm shift in which each new paradigm replaces the last, there seems to be a resurgence of men’s health issues at the forefront, together with or in place of women’s health policy and promotion. Men and women’s health have gained widespread attention in popular magazines, television shows, and in the wellness industry. Not surprisingly, there have been many calls to close the gap between men and women in longevity and illness experience. Reports by WHO clearly advocate the importance of a gender perspective to assist in understanding ageing and health, and stress the importance of research in clinical science and public health acknowledging gender differences.3,4 The Canadian report The health divide: how the sexes differ discusses life expectancy and reasons behind differences between women and men.2 To comment on the European experience, the differences in life expectancy are striking. In eastern European countries, especially in Russia, the gap is not 6 years, as reported for Canada, but closer to 10 years. In 2000, the WHO report suggested a 77% increased risk of premature death for Russian men between 1987 and 1994. With life expectancy, the gap between the sexes generally decreases as average life expectancy increases. Russia has one of the lowest life expectancies and, therefore, the widest gaps between sexes in healthy life expectancy in the world (66·4 vs 56·1 years for men compared with women).3 Undoubtedly, we must identify men as a high-risk group for premature death in this population. In 1999, the Institute of Social Medicine prepared a scientific report on men’s health for the Viennese government, to offer the health system a basis on which to identify focal points on men’s health issues.5 We concluded that men need to be specifically addressed as a target group for prevention campaigns and that their health can be significantly improved. Not only must appropriate primary and secondary prevention measures be taken, but support for gender-specific research and dissemination or translation of the results into health-care
THE LANCET • Vol 358 • September 8, 2001
For personal use. Only reproduce with permission from The Lancet Publishing Group.