- Email: [email protected]
Directly observed therapy
THE LANCET
*M Bashar Izzat, Anthony P C Yim Division of Cardiothoracic Surgery, Department of Surgery, Prince of Wales Hospital, Shatin, NT, Hong Kong
1
2
3 4 5
Calafiore AM, Angelini GD. Left anterior small thoracotomy (LAST) without cardiopulmonary bypass. Lancet 1996; 347: 263–64. Schaff HV, Cable DG, Rihal CS, Daly RC, Orszulak TA. Minimal thoracotomy for coronary artery bypass: value of immediate postoperative graft angiography. Circulation 1996; 94 (suppl 1): I–51. Frankel DH. Cardiac surgeons peer through the coronary keyhole. Lancet 1996; 348: 1437. Izzat MB, Yim APC. Editorial: didn’t they do well? Ann Thorac Surg (in press). Angelini GD, Wilde P, Salerno TA, Bosco G, Calafiore AM. Integrated left small thoracotomy and angioplasty for multivessel coronary artery revascularistion. Lancet 1996; 347: 757–58.
Directly observed therapy SIR—J Volmink and Paul Garner (May 10, p 1399)1 cast doubt on the efficacy of directly observed therapy (DOT) in tuberculosis but seem not to have examined adequately what has been published on this topic. Recent evidence suggests that DOT is a very robust control strategy achieving high treatment completion rates, greatly reducing the incidence of tuberculosis within a community, eradicating multidrug-resistant species while
666
Cases per 100 000 population
60 New York City
50
Baltimore
DOT
40 30 DOT 20 10 0
94 19 3 9 19 2 9 19 1 9 19 0 9 19 9 8 19 8 8 19 7 8 19 6 8 19 5 8 19 4 8 19 3 8 19 2 8 19 1 8 19 0 8 19 9 7 19
introduced graft angiography in the operating room for all MIDCAB cases. This is easily done with a standard image intensifier (Philips BV300). At first, a colleague from the cardiology team did the procedure but now, after training, the surgeons do the angiography. We have learned the importance of having angiographic data for the critical appraisal of the procedure, as opposed to relying solely on clinical outcome.4 We have been able to correct the few graft abnormalities met before the patient left theatre and, crucially, we identified the causes of the anomalies and that should help us to avoid them. If we were to identify any anastomotic stenosis or occlusion we would be well placed to redo the procedure. The immediate benefits of this practice have been improved early graft success and elimination of the need for early reoperation. For surgeons in the early phase of their learning curves routine angiography provides the feedback needed to document the success of certain manoeuvres and the usefulness of new coronary artery stabilising devices.4 Moreover, both the surgeons and the cardiologists now have greater confidence in MIDCAB. Routine “on-table” angiography is likely to improve the outcome of internal mammary grafting with MIDCAB.
Years 15-year trends in tuberculosis in two US cities with largest changes in incidence between 1981 and 1992
reducing relapse, and capable of enhancing outcomes for patients with AIDS.2 In Baltimore, USA, for example, DOT has resulted in treatment completion rates which now exceed 90%, sputum conversion rates double those for patients on self-administered therapy, the near eradication of drugresistant species (0·57%), and, maybe, most importantly, a 62% reduction in incidence of tuberculosis between 1981 and 1995.3 Similarly, in New York City, the incidence of tuberculosis increased 299% between 1979 and 1991, but fell by 21% between 1992 and 1994 following implementation of community-based DOT (figure).4 Moreover, there is evidence that DOT is cost-effective compared with self-administered regimens.5 Volmink and Garner focus on this issue. Costeffectiveness is tipped even further in favour of DOT where the incidence of costly-to-treat drug resistance is high (ie, most developing countries). *C Patrick Chaulk, Michael D Iseman Annie E Casey Foundation, 701 St Paul Street, Baltimore, MD 21202, USA
1 2
3
4
5
Volmink J, Garner P. Directly observed therapy. Lancet 1997; 349: 1399–400. Alwood K, Keruly J, Moore-Rice K, Stanton DL, Chaulk CP, Chaisson RE. Effectiveness of supervised, intermittent therapy for tuberculosis in HIV-infected patients. AIDS 1994; 8: 1103–08. Chaulk CP, Pope DS. The Baltimore City Health Department program of directly observed therapy for tuberculosis. Clin Chest Med 1997; 18: 149–54. Frieden TR, Fujiwara PI, Washko RM, Hamburg MA. Tuberculosis in New York City: turning the tide. N Engl J Med 1995; 333: 229–33. Moore RD, Chaulk CP, Griffiths R, Cavalcante S, Chaisson RE. Cost-effectiveness of directly observed versus self-administered therapy for tuberculosis. Am J Respir Crit Care Med 1996; 154: 1013–19.
Authors’ reply SIR—Patrick Chaulk and Michael Iseman do not define the intervention
they are referring to, and there is considerable confusion about what DOTS (directly observed treatment, short course) is. The Director General of WHO defines DOTS as therapy where “TB patients must be observed swallowing each dose of their anti-TB medicine by a health worker or trained volunteer”.1 Others in the Global Tuberculosis Control Programme at WHO state that it includes drugs, buffer stocks, sputum testing facilities with quality control, political commitment, and patient-tracking systems. For Chowdhury et al in Bangladesh, DOTS also includes screening the population, mobilising community health workers, free drugs, comprehensive health education, a national microscopy programme, patients paying an “incentive deposit” of 5 days’ wages, and a written contract.2 Indeed, for Chaulk and Iseman in Baltimore, USA, DOT includes involuntary hospital admission and jail for patients who default from treatment.3 DOTS usually represents a substantive financial and technical investment in tuberculosis programmes, and this is the main reason for the efficacy of the programmes. Indeed, the Lancet commentary on the Bangladesh project suggested that a major reason for success is that the scheme was implemented by “an effective nongovernmental organisation capable of securing technical and financial support from several donor agencies”.4 On the other hand, on the definition of DOTS given by the Director General of WHO, there is no evidence from trials whether this specific strategy is effective, or more effective than other approaches such as patient reminders or defaulter actions.5 Our concern is that developing countries might adopt the specific strategy of directly observing patients take their drugs to solve poor compliance but without a concomitant investment of money, energy, and skilled personnel. In countries where there is a basic tuberculosis control Vol 350 • August 30, 1997
*M Bashar Izzat, Anthony P C Yim Division of Cardiothoracic Surgery, Department of Surgery, Prince of Wales Hospital, Shatin, NT, Hong Kong
1
2
3 4 5
Calafiore AM, Angelini GD. Left anterior small thoracotomy (LAST) without cardiopulmonary bypass. Lancet 1996; 347: 263–64. Schaff HV, Cable DG, Rihal CS, Daly RC, Orszulak TA. Minimal thoracotomy for coronary artery bypass: value of immediate postoperative graft angiography. Circulation 1996; 94 (suppl 1): I–51. Frankel DH. Cardiac surgeons peer through the coronary keyhole. Lancet 1996; 348: 1437. Izzat MB, Yim APC. Editorial: didn’t they do well? Ann Thorac Surg (in press). Angelini GD, Wilde P, Salerno TA, Bosco G, Calafiore AM. Integrated left small thoracotomy and angioplasty for multivessel coronary artery revascularistion. Lancet 1996; 347: 757–58.
Directly observed therapy SIR—J Volmink and Paul Garner (May 10, p 1399)1 cast doubt on the efficacy of directly observed therapy (DOT) in tuberculosis but seem not to have examined adequately what has been published on this topic. Recent evidence suggests that DOT is a very robust control strategy achieving high treatment completion rates, greatly reducing the incidence of tuberculosis within a community, eradicating multidrug-resistant species while
666
Cases per 100 000 population
60 New York City
50
Baltimore
DOT
40 30 DOT 20 10 0
94 19 3 9 19 2 9 19 1 9 19 0 9 19 9 8 19 8 8 19 7 8 19 6 8 19 5 8 19 4 8 19 3 8 19 2 8 19 1 8 19 0 8 19 9 7 19
introduced graft angiography in the operating room for all MIDCAB cases. This is easily done with a standard image intensifier (Philips BV300). At first, a colleague from the cardiology team did the procedure but now, after training, the surgeons do the angiography. We have learned the importance of having angiographic data for the critical appraisal of the procedure, as opposed to relying solely on clinical outcome.4 We have been able to correct the few graft abnormalities met before the patient left theatre and, crucially, we identified the causes of the anomalies and that should help us to avoid them. If we were to identify any anastomotic stenosis or occlusion we would be well placed to redo the procedure. The immediate benefits of this practice have been improved early graft success and elimination of the need for early reoperation. For surgeons in the early phase of their learning curves routine angiography provides the feedback needed to document the success of certain manoeuvres and the usefulness of new coronary artery stabilising devices.4 Moreover, both the surgeons and the cardiologists now have greater confidence in MIDCAB. Routine “on-table” angiography is likely to improve the outcome of internal mammary grafting with MIDCAB.
Years 15-year trends in tuberculosis in two US cities with largest changes in incidence between 1981 and 1992
reducing relapse, and capable of enhancing outcomes for patients with AIDS.2 In Baltimore, USA, for example, DOT has resulted in treatment completion rates which now exceed 90%, sputum conversion rates double those for patients on self-administered therapy, the near eradication of drugresistant species (0·57%), and, maybe, most importantly, a 62% reduction in incidence of tuberculosis between 1981 and 1995.3 Similarly, in New York City, the incidence of tuberculosis increased 299% between 1979 and 1991, but fell by 21% between 1992 and 1994 following implementation of community-based DOT (figure).4 Moreover, there is evidence that DOT is cost-effective compared with self-administered regimens.5 Volmink and Garner focus on this issue. Costeffectiveness is tipped even further in favour of DOT where the incidence of costly-to-treat drug resistance is high (ie, most developing countries). *C Patrick Chaulk, Michael D Iseman Annie E Casey Foundation, 701 St Paul Street, Baltimore, MD 21202, USA
1 2
3
4
5
Volmink J, Garner P. Directly observed therapy. Lancet 1997; 349: 1399–400. Alwood K, Keruly J, Moore-Rice K, Stanton DL, Chaulk CP, Chaisson RE. Effectiveness of supervised, intermittent therapy for tuberculosis in HIV-infected patients. AIDS 1994; 8: 1103–08. Chaulk CP, Pope DS. The Baltimore City Health Department program of directly observed therapy for tuberculosis. Clin Chest Med 1997; 18: 149–54. Frieden TR, Fujiwara PI, Washko RM, Hamburg MA. Tuberculosis in New York City: turning the tide. N Engl J Med 1995; 333: 229–33. Moore RD, Chaulk CP, Griffiths R, Cavalcante S, Chaisson RE. Cost-effectiveness of directly observed versus self-administered therapy for tuberculosis. Am J Respir Crit Care Med 1996; 154: 1013–19.
Authors’ reply SIR—Patrick Chaulk and Michael Iseman do not define the intervention
they are referring to, and there is considerable confusion about what DOTS (directly observed treatment, short course) is. The Director General of WHO defines DOTS as therapy where “TB patients must be observed swallowing each dose of their anti-TB medicine by a health worker or trained volunteer”.1 Others in the Global Tuberculosis Control Programme at WHO state that it includes drugs, buffer stocks, sputum testing facilities with quality control, political commitment, and patient-tracking systems. For Chowdhury et al in Bangladesh, DOTS also includes screening the population, mobilising community health workers, free drugs, comprehensive health education, a national microscopy programme, patients paying an “incentive deposit” of 5 days’ wages, and a written contract.2 Indeed, for Chaulk and Iseman in Baltimore, USA, DOT includes involuntary hospital admission and jail for patients who default from treatment.3 DOTS usually represents a substantive financial and technical investment in tuberculosis programmes, and this is the main reason for the efficacy of the programmes. Indeed, the Lancet commentary on the Bangladesh project suggested that a major reason for success is that the scheme was implemented by “an effective nongovernmental organisation capable of securing technical and financial support from several donor agencies”.4 On the other hand, on the definition of DOTS given by the Director General of WHO, there is no evidence from trials whether this specific strategy is effective, or more effective than other approaches such as patient reminders or defaulter actions.5 Our concern is that developing countries might adopt the specific strategy of directly observing patients take their drugs to solve poor compliance but without a concomitant investment of money, energy, and skilled personnel. In countries where there is a basic tuberculosis control Vol 350 • August 30, 1997