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Antihypertensive drugs differ in ability to lower left ventricular mass
THE LANCET
SCIENCE AND MEDICINE
Facing up to tomorrow’s epidemics E coli O157 and the bovine spongiform encephalopathy agent. “Whenever we change our behaviour and relationship to the environment, we come up with new diseases”, noted Adetokunbo Lucas, Harvard School of Public Health (Boston, MA, USA). Many humaninduced socioeconomic and environmental changes, notably population growth and increasing urbanisation, can be blamed for creating new opportunities for pathogens. Climate changes may also contribute (panel). The management of tomorrow’s epidemics should be based on existing systems. But, the public-health infrastructure is failing in many poor countries. New technology is only part of the solution but electronic communications are a “striking development”, said Brian Greenwood (LSHTM). However, simple, sustainable interventions are also needed. The sad news from Pierre Rollin (CDC) was that the infectioncontrol procedures introduced at Kikwit hospital to contain Ebola have now been abandoned. As the forum How can climate change cause epidemics? closed, reports of the One example is the association of a prolonged El worst outbreak of Niño (abnormal Pacific Ocean Lassa fever since warming) with epidemic cholera records began came in in South America since 1991. from Sierra Leone. Warming may increase phytoMedical Emergency plankton biomass (algal Relief International blooms, as seen by satellite said case numbers had on left). This encourages doubled there since growth of zooplankton, which December, 1996. are the environmental reservoir for Vibrio cholerae ( Science 1996; 274: 2025–31).
orldwide, the threat of infectious diseases is increasing, from both old scourges and new pathogens. But we may not be prepared for tomorrow’s epidemics. That was the main conclusion of New and Resurgent Infections, the seventh annual public-health forum at the London School of Hygiene and Tropical Medicine, UK, 22–25 April. Emerging communicable diseases are not new. Well-known examples include the HIV-1 pandemic and the 1995 Ebola outbreak in Kikwit, Zaire. But more “biological surprises” are expected. Duane Gubler, US Centers for Disease Control and Prevention (Atlanta, GA, USA), described the re-invasion of many urban areas by the mosquito Aedes aegyptii, leading to a dramatic rise in dengue virus infections, including haemorrhagic fever, in nearly 50 countries worldwide. In the Americas, the risk of urban yellow fever from A aegyptii is now the highest in 50 years, said Gubler. New pathogens are also emerging, such as
Science Photo Library
W
Two trials in children with juvenile chronic arthritis also offer some hope. MAJ van Rossum, Leiden, Netherlands, recorded significant improvement with both placebo and sulphasalazine in 69 children, aged 2–18 years—the effect was greatest in the drug-treatment group. A crossover study of methotrexate in 100 patients, presented by Prof P Woo, London, UK, showed similar improvements to the Dutch trial. In the methotrexate trial, doctors’ and parents’ assessment of benefit was greater than that of the children, but Woo noted that truthfulness in children is difficult to judge. Stephanie Clark
Jane Bradbury
Treatments for arthritis look promising ncouraging results from several clinical trials on treatments for rheumatoid diseases were reported at a joint meeting of the British and Dutch societies for rheumatology in Harrogate, UK (April 23-25). In one European collaborative trial, 472 patients with active severe rheumatoid arthritis were treated for 24 weeks with human recombinant interleukin-1ra, a naturally occurring inhibitor of interleukin-1. Prof B Bresnihan, Dublin, Ireland, reported improvement in several indices (notably, number of tender joints, pain, and erythrocyte sedimentation rate). The trial was continued for a further 6 months and improvement was maintained.
Vol 349 • May 3, 1997
T
he diuretic hydrochlorothiazide, the ACE inhibitor captopril, and the -blocker atenolol significantly reduce left ventricular (LV) mass in men with mild-tomoderate hypertension, report the Veterans Association Cooperative Study Group on Antihypertensive Agents. But, other classes of antihypertensive drugs, represented by diltiazem, clonidine, and prazosin did not significantly affect LV mass. The strong correlation between LV hypertrophy and the risk of cardiovascular events in hypertensive patients is well documented. But, the ability of different forms of antihypertensive therapy to reduce LV mass remains under debate. 1105 men (initial diastolic blood pressure of 95–109 mm Hg) were recruited at 15 VA Medical Centers for the single-drug antihypertensive treatment study. The patients were randomly assigned to one of six antihypertensive drugs or placebo— this last group were not discussed in the study report (Circulation 1997; 95: 2007–14). 683 patients whose blood pressure dropped below 90 mm Hg by 8 weeks were entered into the treatment trial. At the end of 1 year, 493 patients remained in the trial but only 230 patients had had echocardiographic measurements to determine LV mass at baseline, 8 weeks, and 1 year. Between 28 and 52 of these patients were in each treatment arm. After adjustment for other factors affecting LV mass, the VA study group report that LV mass was decreased at 1 year for patients in the highest tertile of baseline LV mass who were treated with hydrochlorothiazide, captopril, or atenolol. “The results of our study establish that, at least in some circumstances, differences may exist between drugs for reduction of LV mass”, says John Gottdiener (Georgetown University Hospital, Washington, DC, USA), lead author on the paper. But both Gottdiener and Richard Devereux (Cornell Medical Center, New York, NY, USA), in an accompanying editorial, note that larger trials are needed to establish the role of antihypertensive drugs in LV mass reduction.
Kelly Morris
E
Antihyper tensive drugs differ in ability to lower left ventricular mass
1301
SCIENCE AND MEDICINE
Facing up to tomorrow’s epidemics E coli O157 and the bovine spongiform encephalopathy agent. “Whenever we change our behaviour and relationship to the environment, we come up with new diseases”, noted Adetokunbo Lucas, Harvard School of Public Health (Boston, MA, USA). Many humaninduced socioeconomic and environmental changes, notably population growth and increasing urbanisation, can be blamed for creating new opportunities for pathogens. Climate changes may also contribute (panel). The management of tomorrow’s epidemics should be based on existing systems. But, the public-health infrastructure is failing in many poor countries. New technology is only part of the solution but electronic communications are a “striking development”, said Brian Greenwood (LSHTM). However, simple, sustainable interventions are also needed. The sad news from Pierre Rollin (CDC) was that the infectioncontrol procedures introduced at Kikwit hospital to contain Ebola have now been abandoned. As the forum How can climate change cause epidemics? closed, reports of the One example is the association of a prolonged El worst outbreak of Niño (abnormal Pacific Ocean Lassa fever since warming) with epidemic cholera records began came in in South America since 1991. from Sierra Leone. Warming may increase phytoMedical Emergency plankton biomass (algal Relief International blooms, as seen by satellite said case numbers had on left). This encourages doubled there since growth of zooplankton, which December, 1996. are the environmental reservoir for Vibrio cholerae ( Science 1996; 274: 2025–31).
orldwide, the threat of infectious diseases is increasing, from both old scourges and new pathogens. But we may not be prepared for tomorrow’s epidemics. That was the main conclusion of New and Resurgent Infections, the seventh annual public-health forum at the London School of Hygiene and Tropical Medicine, UK, 22–25 April. Emerging communicable diseases are not new. Well-known examples include the HIV-1 pandemic and the 1995 Ebola outbreak in Kikwit, Zaire. But more “biological surprises” are expected. Duane Gubler, US Centers for Disease Control and Prevention (Atlanta, GA, USA), described the re-invasion of many urban areas by the mosquito Aedes aegyptii, leading to a dramatic rise in dengue virus infections, including haemorrhagic fever, in nearly 50 countries worldwide. In the Americas, the risk of urban yellow fever from A aegyptii is now the highest in 50 years, said Gubler. New pathogens are also emerging, such as
Science Photo Library
W
Two trials in children with juvenile chronic arthritis also offer some hope. MAJ van Rossum, Leiden, Netherlands, recorded significant improvement with both placebo and sulphasalazine in 69 children, aged 2–18 years—the effect was greatest in the drug-treatment group. A crossover study of methotrexate in 100 patients, presented by Prof P Woo, London, UK, showed similar improvements to the Dutch trial. In the methotrexate trial, doctors’ and parents’ assessment of benefit was greater than that of the children, but Woo noted that truthfulness in children is difficult to judge. Stephanie Clark
Jane Bradbury
Treatments for arthritis look promising ncouraging results from several clinical trials on treatments for rheumatoid diseases were reported at a joint meeting of the British and Dutch societies for rheumatology in Harrogate, UK (April 23-25). In one European collaborative trial, 472 patients with active severe rheumatoid arthritis were treated for 24 weeks with human recombinant interleukin-1ra, a naturally occurring inhibitor of interleukin-1. Prof B Bresnihan, Dublin, Ireland, reported improvement in several indices (notably, number of tender joints, pain, and erythrocyte sedimentation rate). The trial was continued for a further 6 months and improvement was maintained.
Vol 349 • May 3, 1997
T
he diuretic hydrochlorothiazide, the ACE inhibitor captopril, and the -blocker atenolol significantly reduce left ventricular (LV) mass in men with mild-tomoderate hypertension, report the Veterans Association Cooperative Study Group on Antihypertensive Agents. But, other classes of antihypertensive drugs, represented by diltiazem, clonidine, and prazosin did not significantly affect LV mass. The strong correlation between LV hypertrophy and the risk of cardiovascular events in hypertensive patients is well documented. But, the ability of different forms of antihypertensive therapy to reduce LV mass remains under debate. 1105 men (initial diastolic blood pressure of 95–109 mm Hg) were recruited at 15 VA Medical Centers for the single-drug antihypertensive treatment study. The patients were randomly assigned to one of six antihypertensive drugs or placebo— this last group were not discussed in the study report (Circulation 1997; 95: 2007–14). 683 patients whose blood pressure dropped below 90 mm Hg by 8 weeks were entered into the treatment trial. At the end of 1 year, 493 patients remained in the trial but only 230 patients had had echocardiographic measurements to determine LV mass at baseline, 8 weeks, and 1 year. Between 28 and 52 of these patients were in each treatment arm. After adjustment for other factors affecting LV mass, the VA study group report that LV mass was decreased at 1 year for patients in the highest tertile of baseline LV mass who were treated with hydrochlorothiazide, captopril, or atenolol. “The results of our study establish that, at least in some circumstances, differences may exist between drugs for reduction of LV mass”, says John Gottdiener (Georgetown University Hospital, Washington, DC, USA), lead author on the paper. But both Gottdiener and Richard Devereux (Cornell Medical Center, New York, NY, USA), in an accompanying editorial, note that larger trials are needed to establish the role of antihypertensive drugs in LV mass reduction.
Kelly Morris
E
Antihyper tensive drugs differ in ability to lower left ventricular mass
1301