- Email: [email protected]
DEAFNESS IN CHILDREN
105 odds ratios consistent with the smoking and lung cancer:
magnitude
of those found for
RR (and 90%
confidence
Variable Ever smoked Smoked 15 yr ago Smoked 5 yr ago
limits) 6-8* 8 - 7*
(4-1, 11 -3) (5 - 3, 14-3) 8 - 2* (5 - 2, 13 - 2)
(two-tailed). The odds ratios can be calculated RAS and "ever smoked":
*p<0-001
separately for the two types of
RR Disease Atherosclerotic RAS Fibromuscular RAS
*p<0-001
(and 90% confidence limits) 10 - 2* (5. 4, 19. 1) 3 - 61 (1 - 6, 8 - 0)
(two-tailed); fp-0-009 (two-tailed).
Division of Epidemiology, Department of Family and Community Medicine, University of Utah School of Medicine, Medical Center, Salt Lake City, Utah 84132, USA
JOSEPH L. LYON KATHARINA L. SCHUMAN ELECTRA D. AVLON
SIR,-Hypertension is common in Blacks in the United States, and some reports have suggested that it is less likely to be caused by renovascular disease in Blacks than in Whites. Also, there have been racial differences in smoking rates, though these differences are changing. In Dr Nicholson and colleagues’ study was there any difference in the black-white ratio between the patients with renal artery stenosis and the controls? Department of Medicine, University of Mississippi Medical Center, Jackson, Mississippi 39216, USA
***These letters have been shown colleagues, whose reply follows.-ED. SIR,-Dr Lyon and his colleagues
HERBERT G. LANGFORD
to
Dr Nicholson and his
L.
define our study as a casecalled it a retrospective cohort study.l However, review of the definitions in the book Lyon et al refer to suggests that the distinction is semantic and its authors state that "The terms retrospective ... have been used by some workers to refer what we have called case control studies and cohort studies". Whatever the distinction, Lyon and colleagues’ use of risk ratios certainly enhances analysis of our data and supports the observation we
reported. Smoking histories were reported not only as "ever smoked" but also stratified with respect to cessation of smoking 15,5-15 years, or 5 years previously. Regardless of the stratification, the percentage of smoking in patients with renal artery stenosis was nearly twice that we
of the control group. The distinction between fibromuscular disease and atherosclerosis was done on strict angiographic criteria, thus minimising misclassification of cases by use of the best method available. We agree that a small risk of bias was introduced by our more thorough inquiry into the smoking histories of patients with renal artery stenosis. However, if patients whose smoking histories were obtained only by telephone are eliminated, a two-fold difference persists. In answer to Professor Langford, 8-1% of our controls and 5 -6% of our patients with renal artery stenosis were Black. Despite the small percentages of Blacks, the relation between smoking and renal artery stenosis holds true-that is, 11 of 25 Black controls (44%) had a history of smoking cigarettes, while 75% of the patients who were Black and had renal artery stenosis were smokers.
JOHN P. NICHOLSON
New York Hospital-Cornell Medical Center,
New York, NY 10021, USA
1. Feinstein
SiR,-Your Dec 10 editorial on secretory otitis media highlights the problems associated with the detection of hearing loss in schoolchildren. As an adjunct to screening children’s hearing objectively, with impedance and tympanometry, a history of ear pain, deafness, inattention, and so on, as noted by parents and teachers, has been neglected; most of these children are tested unaccompanied. There seems little point in referring a child who is "top of the class" who fails two consecutive impedance tests 6-8 weeks apart, when the usual outpatient waiting time for an ENT clinic appointment can be 10-14 weeks. Great emphasis has been placed on the rapid surgical correction achievable in the child who has persistent middle-ear effusion with a hearing loss. This point should be made to the Department of Health by community physicians, general practitioners, teachers of the deaf, and school health visitors. The views of ENT consultants have long been overlooked when ENT paediatric beds are reviewed. The number of medically and non-medically qualified staff who undertake hearing tests in schools has much increased but the surgical hands and beds needed to deal with resulting increased workload are contracting. Department of Otolaryngology, University Hospital, Queen’s Medical Centre, Nottingham NG7 2UH
P. J. BRADLEY
UNIVERSAL HOME HAEMODIALYSIS
SIR,-We strongly support Dr Cjeorgecontention (Uct 15, p
School of Medicine,
control one, whereas
DEAFNESS IN CHILDREN
SAM L. TEICHMAN MICHAEL H. ALDERMAN T. A. SOS T. G. PICKERING JOHN H. LARAGH
AR, Horwitz RI. Double standards, scientific methods, research. N Engl J Med 1983; 307: 1611-17.
and
epidemiologic
895) that universal home haemodialysis is feasible for an unselected group of patients. In Christchurch, New Zealand, we provide a renal replacement programme based on home haemodialysis and transplantation. There are no facilities for long-term hospital dialysis. From late 1969 to November, 1983, 212 patients aged 6-72 years began training for home haemodialysis; 187 went home with their machines, 7 received transplants during the training period, and 18 (9-6%) died. A further 12 patients have been trained for peritoneal dialysis (CAPD), of whom 8 patients went home and the other 4 died during the training period. Of the 187 patients established on home haemodialysis, 96 (51°70) were from other health authorities, some living up to 400 miles (640 km) away. The patients use conventional haemodialysis equipment both during the training period and at home. While training they do four 5 h dialyses per week in a minimally converted house outside the hospital environment. Training and technical services are provided by a staff of four technicians with weekly supervision by one nephrologist. At home the patients dialyse for 18- 30 h per week. Primary care is the responsibility of the general practitioner, with a consultative service being provided by the nephrology staff. Patients are fully reviewed by a nephrologist every year. Technical advice and servicing is available 24 h a day from the training centre. Like George we believe that the responsibility for the treatment rests with the patients. 6 patients have required a "dialysis helper" who is not a member of the family (5 paid sitters and 1 person who is entirely responsible for the dialysis). We have 35 patients currently on home haemodialysis. 33 dialyse in their homes and 2 dialyse in small regional hospitals but remain responsible for their own treatment. 23 patients are in full-time or part-time employment, 2 are seeking work, 5 patients aged over 60 years are retired, and 5 are unemployed. We agree that home haemodialysis is feasible for all patients and that this form of treatment is not only cheaper than CAPD or other forms of haemodialysis, but also affords the patient an opportunity of rehabilitation without serious dependence on hospital or medical services. We agree also with George’s emphasis that most technical problems can be dealt with reasonably easily. Successful treatment is dependent more on the patient’s motivation than on technical skill.
Department of Nephrology, Christchurch Hospital, Christchurch, New Zealand
KELVIN L. LYNN ADRIAN L. BUTTIMORE Ross R. BAILEY CHARLES P. SWAINSON
magnitude
of those found for
RR (and 90%
confidence
Variable Ever smoked Smoked 15 yr ago Smoked 5 yr ago
limits) 6-8* 8 - 7*
(4-1, 11 -3) (5 - 3, 14-3) 8 - 2* (5 - 2, 13 - 2)
(two-tailed). The odds ratios can be calculated RAS and "ever smoked":
*p<0-001
separately for the two types of
RR Disease Atherosclerotic RAS Fibromuscular RAS
*p<0-001
(and 90% confidence limits) 10 - 2* (5. 4, 19. 1) 3 - 61 (1 - 6, 8 - 0)
(two-tailed); fp-0-009 (two-tailed).
Division of Epidemiology, Department of Family and Community Medicine, University of Utah School of Medicine, Medical Center, Salt Lake City, Utah 84132, USA
JOSEPH L. LYON KATHARINA L. SCHUMAN ELECTRA D. AVLON
SIR,-Hypertension is common in Blacks in the United States, and some reports have suggested that it is less likely to be caused by renovascular disease in Blacks than in Whites. Also, there have been racial differences in smoking rates, though these differences are changing. In Dr Nicholson and colleagues’ study was there any difference in the black-white ratio between the patients with renal artery stenosis and the controls? Department of Medicine, University of Mississippi Medical Center, Jackson, Mississippi 39216, USA
***These letters have been shown colleagues, whose reply follows.-ED. SIR,-Dr Lyon and his colleagues
HERBERT G. LANGFORD
to
Dr Nicholson and his
L.
define our study as a casecalled it a retrospective cohort study.l However, review of the definitions in the book Lyon et al refer to suggests that the distinction is semantic and its authors state that "The terms retrospective ... have been used by some workers to refer what we have called case control studies and cohort studies". Whatever the distinction, Lyon and colleagues’ use of risk ratios certainly enhances analysis of our data and supports the observation we
reported. Smoking histories were reported not only as "ever smoked" but also stratified with respect to cessation of smoking 15,5-15 years, or 5 years previously. Regardless of the stratification, the percentage of smoking in patients with renal artery stenosis was nearly twice that we
of the control group. The distinction between fibromuscular disease and atherosclerosis was done on strict angiographic criteria, thus minimising misclassification of cases by use of the best method available. We agree that a small risk of bias was introduced by our more thorough inquiry into the smoking histories of patients with renal artery stenosis. However, if patients whose smoking histories were obtained only by telephone are eliminated, a two-fold difference persists. In answer to Professor Langford, 8-1% of our controls and 5 -6% of our patients with renal artery stenosis were Black. Despite the small percentages of Blacks, the relation between smoking and renal artery stenosis holds true-that is, 11 of 25 Black controls (44%) had a history of smoking cigarettes, while 75% of the patients who were Black and had renal artery stenosis were smokers.
JOHN P. NICHOLSON
New York Hospital-Cornell Medical Center,
New York, NY 10021, USA
1. Feinstein
SiR,-Your Dec 10 editorial on secretory otitis media highlights the problems associated with the detection of hearing loss in schoolchildren. As an adjunct to screening children’s hearing objectively, with impedance and tympanometry, a history of ear pain, deafness, inattention, and so on, as noted by parents and teachers, has been neglected; most of these children are tested unaccompanied. There seems little point in referring a child who is "top of the class" who fails two consecutive impedance tests 6-8 weeks apart, when the usual outpatient waiting time for an ENT clinic appointment can be 10-14 weeks. Great emphasis has been placed on the rapid surgical correction achievable in the child who has persistent middle-ear effusion with a hearing loss. This point should be made to the Department of Health by community physicians, general practitioners, teachers of the deaf, and school health visitors. The views of ENT consultants have long been overlooked when ENT paediatric beds are reviewed. The number of medically and non-medically qualified staff who undertake hearing tests in schools has much increased but the surgical hands and beds needed to deal with resulting increased workload are contracting. Department of Otolaryngology, University Hospital, Queen’s Medical Centre, Nottingham NG7 2UH
P. J. BRADLEY
UNIVERSAL HOME HAEMODIALYSIS
SIR,-We strongly support Dr Cjeorgecontention (Uct 15, p
School of Medicine,
control one, whereas
DEAFNESS IN CHILDREN
SAM L. TEICHMAN MICHAEL H. ALDERMAN T. A. SOS T. G. PICKERING JOHN H. LARAGH
AR, Horwitz RI. Double standards, scientific methods, research. N Engl J Med 1983; 307: 1611-17.
and
epidemiologic
895) that universal home haemodialysis is feasible for an unselected group of patients. In Christchurch, New Zealand, we provide a renal replacement programme based on home haemodialysis and transplantation. There are no facilities for long-term hospital dialysis. From late 1969 to November, 1983, 212 patients aged 6-72 years began training for home haemodialysis; 187 went home with their machines, 7 received transplants during the training period, and 18 (9-6%) died. A further 12 patients have been trained for peritoneal dialysis (CAPD), of whom 8 patients went home and the other 4 died during the training period. Of the 187 patients established on home haemodialysis, 96 (51°70) were from other health authorities, some living up to 400 miles (640 km) away. The patients use conventional haemodialysis equipment both during the training period and at home. While training they do four 5 h dialyses per week in a minimally converted house outside the hospital environment. Training and technical services are provided by a staff of four technicians with weekly supervision by one nephrologist. At home the patients dialyse for 18- 30 h per week. Primary care is the responsibility of the general practitioner, with a consultative service being provided by the nephrology staff. Patients are fully reviewed by a nephrologist every year. Technical advice and servicing is available 24 h a day from the training centre. Like George we believe that the responsibility for the treatment rests with the patients. 6 patients have required a "dialysis helper" who is not a member of the family (5 paid sitters and 1 person who is entirely responsible for the dialysis). We have 35 patients currently on home haemodialysis. 33 dialyse in their homes and 2 dialyse in small regional hospitals but remain responsible for their own treatment. 23 patients are in full-time or part-time employment, 2 are seeking work, 5 patients aged over 60 years are retired, and 5 are unemployed. We agree that home haemodialysis is feasible for all patients and that this form of treatment is not only cheaper than CAPD or other forms of haemodialysis, but also affords the patient an opportunity of rehabilitation without serious dependence on hospital or medical services. We agree also with George’s emphasis that most technical problems can be dealt with reasonably easily. Successful treatment is dependent more on the patient’s motivation than on technical skill.
Department of Nephrology, Christchurch Hospital, Christchurch, New Zealand
KELVIN L. LYNN ADRIAN L. BUTTIMORE Ross R. BAILEY CHARLES P. SWAINSON