824
The desirability, however, of allowing cost-benefit data to be used for advertising is surely not in question. There is no dispute about the use of efficacy data since this forms part of the basis of applications for licensing by the Committee on Safety of Medicines. Pharmaceutical companies are required to publish the prices of their products and it seems ridiculous to prevent them from discussing the relation between these variables, for the products of their own or other companies. There is nothing to prevent doctors or clinical scientists publishing cost-benefit analyses of different approaches to the pharmacological treatment of symptoms or disease, and it is not logical to prevent pharmaceutical companies making use of this information in their advertising. Indeed, we are increasingly conscious of the fact that clinical endeavours are limited predominantly by money and clinicians are more than ever encouraged to examine the costs of their activities. Since expenditure in one clinical area denies funding to another it is unethical to do otherwise. Much of the stimulus and the funding to acquire cost-benefit information comes from the pharmaceutical industry and in my view it would be quite unreasonable to prevent these companies making use of the data obtained. There should of course be sanctions available for false claims, as there are for other information contained in promotional material.
variations of the prevalence of the disease and of the relevant number of sunshine hours. The largest group (ENE) showed no significant seasonal variation in the overall prevalence of open-angle glaucoma for either sex. There were twice as many women in this group as men (p < < 10-1°). Since there was no significant difference between the two distributions by sex for either type of glaucoma the data for both sexes were combined. However, the ENE group showed a significant variation for narrow/closed angle glaucoma, which correlated with that for sunshine hours (table). In contrast, the other two groups showed seasonal variations for open-angle glaucoma but the numbers for narrow/closed angle glaucoma were too small for statistical analysis. The results for the ENE group are consistent with the hypothesis. Those in the two other groups with open-angle glaucoma were unexpected. Group C shows a striking seasonal variation which just misses being significant, and it should be noted that the monthly variation of sunshine hours in the Caribbean region is negligible, compared with the conditions in the two other regions. Group SEA shows a powerful variation. Whether these results can be attributed to a photic effect on the development of the infant eye2 or to dietary effects in the later stages of pregnancy is uncertain. But it is noteworthy that a typically agerelated condition seems to be associated with events very early in life.
Department of Medicine, University Hospital of South Manchester,
I thank the surgeons and other
J. P. MILLER
Manchester M20 8LR, UK
Glaucoma and
season
of birth
SIR,-In comparison with age-matched caucasians, the Bantu tribe in South Africa shows only half the prevalence of narrow or closed angle glaucoma, presumably because their crystalline lenses are substantially thinner than those of caucasians.1 The lens may hence press less against the iris, and therefore compress the outflow channels of the aqueous humour less than would be true of lenses in caucasians, which are more liable to raise the intraocular pressure and so increase the chance of glaucoma. The mass of crystalline lenses in Nigerian neonatal pigs increases with birth occurring later in the dry season, but falls progressively the later it happens in the wet season.2 The postnatal rate of growth varies inversely with lenticular mass. If the thickness of the crystalline lens constitutes a predisposing factor for at least one type of glaucoma, and since, in one mammalian species, it varies with the season of birth, the prevalence of closed/narrow angle glaucoma might prove to vary with the patient’s date of birth. To test this hypothesis 701 patients were examined at Moorfields Eye Hospital, London. Diagnosis, date of birth, place of birth, ethnic group, and gender were recorded. Patients with open-angle, narrow-angle, or closedangle glaucoma were included, and they were classed according to their origin as south-east Asian (SEA), Europe and the near east (ENE), or the Caribbean region (C), to allow for local differences in sunshine hours,3 and monthly variations in births.4 The seasonality, if any, of the prevalence of glaucoma was tested as follows. The percentage of cases in any one sequence of six consecutive months (P) was compared with that in the remainder (Q), the total number of cases being n. The probability (p) of the test ratio being due to chance was calculated. The lowest p-value for any two pairs of complementary six-month periods was determined. A comparison was made also between monthly arguments (variations about the mean) of the seasonal
Moorfields Eye Hospital, London EC-1V 4JP, UK, and Age Concern Institute of King’s College London 1. Clemmesen
colleagues for their help.
Gerontology,
R. A. WEALE
V, Luntz MH. Lens thickness and angle-closure glaucoma. Acta
Ophthalmol 1976; 54:
193-97.
Alaku O, Steinbach J Effects of season of birth and age on eye lenses weight in pigs in the humid equatorial tropics. Growth 1982; 46: 22-25. 3. Houghton DD, ed Handbook of applied meteorology. New York: John Wiley, 1985. 4. Chambers R, Longhurst R, Paley A, eds. Seasonal dimensions to rural poverty London: Frances Pinter, 1981. 2
Fish oil and
psoriasis
SIR,-Dr Menter and Dr Barker’s review of the management of psoriasis (July 27, p 231) did not mention the role of dietary fish oil supplementation. Epidemiological studies have demonstrated a lower incidence of psoriasis in Greenland Eskimos than in European controls.1 This has been attributed to the Eskimo’s fishy diet which is high in n-3 fatty acids.2 Derivatives of arachidonic acid, especially leukotriene B4, have been implicated in the pathogenesis of psoriasis. Dietary supplementation with fish oil results in the generation of less inflammatory leukotrienes of the 5 series. Leukotriene Bs is a less potent stimulator of neutrophil chemotaxis3 and keratinocyte proliferation’ than leukotriene B4’ Clinical trials have demonstrated an improvement in psoriasis with the addition of fish oil to the patients regimen.5-7 Also, the hypotriglyceridaemic effect of fish oil may confer an additional benefit during combined therapy with etretinate. Department of Medicine, Division of Rheumatology, Medical College of Wisconsin, Milwaukee, Wisconsin 53226, USA
GERALDINE MCCARTHY
= (P-Q)/ PQ/n
ANALYSIS OF SEASONAL PREVALENCES OF OPEN-ANGLE AND NARROW/CLOSED ANGLE GLAUCOMA IN THREE ETHNIC GROUPS
*1-12= Jan-Dec
tp=0033
Kromann N, Green A. Epidemiological studies m the Upernavik District, Greenland. Acta Med Scand 1989; 208: 401-06. 2. Dyerberg J, Bang HO, Stofferson HO, Moncada S, Vane J. Eicosapentaenoic acid prevention of thrombosis and atherosclerosis. Lancet 1978; ii: 117-19. 3 Lee TH, Mencia-Huerta J-M, Shih C, et al. Characterization and biologic properties of 5,12-dihydroxy derivatives of eicosapentaenoic acid, including leukotriene B5 and the double lipoxygenase product.J Biol Chem 1984; 259: 2383-89. 4. Kragballe K, Voorhees JJ, Goetzl EJ. Leukotnene B5 derivative from eicosapentaenoic acid does not stimulate DNA synthesis of cultural human keratinocytes but inhibits the stimulation induced by leukotriene B4. J Invest Dermatol 1985; 84: 349. 5. Bittiner SB, Cartwright I, Tucker WFG, Bleehen SS. A double-blind randomised placebo-controlled trial of fish oil in psoriasis. Lancet 1988; i: 378-80. 6. Ziboh VA, Cohen KA, Ellis CN, et al. Effects of dietary supplementation of fish oil on neutrophil and epidermal fatty acids. Modulation of clinical course of psoriatic subjects. Arch Dermatol 1986; 122: 1277-82. 7. Lassus AL, Dahlgren A-L, Halpern MJ, Sntalahti J, Happonen H-P. Effects of dietary supplementation with polyunsaturated ethyl ester lipids (Angiosan) in patients with psoriasis and psoriatic arthritis.J Int Med Res 1990; 18: 68-73. 1.
The desirability, however, of allowing cost-benefit data to be used for advertising is surely not in question. There is no dispute about the use of efficacy data since this forms part of the basis of applications for licensing by the Committee on Safety of Medicines. Pharmaceutical companies are required to publish the prices of their products and it seems ridiculous to prevent them from discussing the relation between these variables, for the products of their own or other companies. There is nothing to prevent doctors or clinical scientists publishing cost-benefit analyses of different approaches to the pharmacological treatment of symptoms or disease, and it is not logical to prevent pharmaceutical companies making use of this information in their advertising. Indeed, we are increasingly conscious of the fact that clinical endeavours are limited predominantly by money and clinicians are more than ever encouraged to examine the costs of their activities. Since expenditure in one clinical area denies funding to another it is unethical to do otherwise. Much of the stimulus and the funding to acquire cost-benefit information comes from the pharmaceutical industry and in my view it would be quite unreasonable to prevent these companies making use of the data obtained. There should of course be sanctions available for false claims, as there are for other information contained in promotional material.
variations of the prevalence of the disease and of the relevant number of sunshine hours. The largest group (ENE) showed no significant seasonal variation in the overall prevalence of open-angle glaucoma for either sex. There were twice as many women in this group as men (p < < 10-1°). Since there was no significant difference between the two distributions by sex for either type of glaucoma the data for both sexes were combined. However, the ENE group showed a significant variation for narrow/closed angle glaucoma, which correlated with that for sunshine hours (table). In contrast, the other two groups showed seasonal variations for open-angle glaucoma but the numbers for narrow/closed angle glaucoma were too small for statistical analysis. The results for the ENE group are consistent with the hypothesis. Those in the two other groups with open-angle glaucoma were unexpected. Group C shows a striking seasonal variation which just misses being significant, and it should be noted that the monthly variation of sunshine hours in the Caribbean region is negligible, compared with the conditions in the two other regions. Group SEA shows a powerful variation. Whether these results can be attributed to a photic effect on the development of the infant eye2 or to dietary effects in the later stages of pregnancy is uncertain. But it is noteworthy that a typically agerelated condition seems to be associated with events very early in life.
Department of Medicine, University Hospital of South Manchester,
I thank the surgeons and other
J. P. MILLER
Manchester M20 8LR, UK
Glaucoma and
season
of birth
SIR,-In comparison with age-matched caucasians, the Bantu tribe in South Africa shows only half the prevalence of narrow or closed angle glaucoma, presumably because their crystalline lenses are substantially thinner than those of caucasians.1 The lens may hence press less against the iris, and therefore compress the outflow channels of the aqueous humour less than would be true of lenses in caucasians, which are more liable to raise the intraocular pressure and so increase the chance of glaucoma. The mass of crystalline lenses in Nigerian neonatal pigs increases with birth occurring later in the dry season, but falls progressively the later it happens in the wet season.2 The postnatal rate of growth varies inversely with lenticular mass. If the thickness of the crystalline lens constitutes a predisposing factor for at least one type of glaucoma, and since, in one mammalian species, it varies with the season of birth, the prevalence of closed/narrow angle glaucoma might prove to vary with the patient’s date of birth. To test this hypothesis 701 patients were examined at Moorfields Eye Hospital, London. Diagnosis, date of birth, place of birth, ethnic group, and gender were recorded. Patients with open-angle, narrow-angle, or closedangle glaucoma were included, and they were classed according to their origin as south-east Asian (SEA), Europe and the near east (ENE), or the Caribbean region (C), to allow for local differences in sunshine hours,3 and monthly variations in births.4 The seasonality, if any, of the prevalence of glaucoma was tested as follows. The percentage of cases in any one sequence of six consecutive months (P) was compared with that in the remainder (Q), the total number of cases being n. The probability (p) of the test ratio being due to chance was calculated. The lowest p-value for any two pairs of complementary six-month periods was determined. A comparison was made also between monthly arguments (variations about the mean) of the seasonal
Moorfields Eye Hospital, London EC-1V 4JP, UK, and Age Concern Institute of King’s College London 1. Clemmesen
colleagues for their help.
Gerontology,
R. A. WEALE
V, Luntz MH. Lens thickness and angle-closure glaucoma. Acta
Ophthalmol 1976; 54:
193-97.
Alaku O, Steinbach J Effects of season of birth and age on eye lenses weight in pigs in the humid equatorial tropics. Growth 1982; 46: 22-25. 3. Houghton DD, ed Handbook of applied meteorology. New York: John Wiley, 1985. 4. Chambers R, Longhurst R, Paley A, eds. Seasonal dimensions to rural poverty London: Frances Pinter, 1981. 2
Fish oil and
psoriasis
SIR,-Dr Menter and Dr Barker’s review of the management of psoriasis (July 27, p 231) did not mention the role of dietary fish oil supplementation. Epidemiological studies have demonstrated a lower incidence of psoriasis in Greenland Eskimos than in European controls.1 This has been attributed to the Eskimo’s fishy diet which is high in n-3 fatty acids.2 Derivatives of arachidonic acid, especially leukotriene B4, have been implicated in the pathogenesis of psoriasis. Dietary supplementation with fish oil results in the generation of less inflammatory leukotrienes of the 5 series. Leukotriene Bs is a less potent stimulator of neutrophil chemotaxis3 and keratinocyte proliferation’ than leukotriene B4’ Clinical trials have demonstrated an improvement in psoriasis with the addition of fish oil to the patients regimen.5-7 Also, the hypotriglyceridaemic effect of fish oil may confer an additional benefit during combined therapy with etretinate. Department of Medicine, Division of Rheumatology, Medical College of Wisconsin, Milwaukee, Wisconsin 53226, USA
GERALDINE MCCARTHY
= (P-Q)/ PQ/n
ANALYSIS OF SEASONAL PREVALENCES OF OPEN-ANGLE AND NARROW/CLOSED ANGLE GLAUCOMA IN THREE ETHNIC GROUPS
*1-12= Jan-Dec
tp=0033
Kromann N, Green A. Epidemiological studies m the Upernavik District, Greenland. Acta Med Scand 1989; 208: 401-06. 2. Dyerberg J, Bang HO, Stofferson HO, Moncada S, Vane J. Eicosapentaenoic acid prevention of thrombosis and atherosclerosis. Lancet 1978; ii: 117-19. 3 Lee TH, Mencia-Huerta J-M, Shih C, et al. Characterization and biologic properties of 5,12-dihydroxy derivatives of eicosapentaenoic acid, including leukotriene B5 and the double lipoxygenase product.J Biol Chem 1984; 259: 2383-89. 4. Kragballe K, Voorhees JJ, Goetzl EJ. Leukotnene B5 derivative from eicosapentaenoic acid does not stimulate DNA synthesis of cultural human keratinocytes but inhibits the stimulation induced by leukotriene B4. J Invest Dermatol 1985; 84: 349. 5. Bittiner SB, Cartwright I, Tucker WFG, Bleehen SS. A double-blind randomised placebo-controlled trial of fish oil in psoriasis. Lancet 1988; i: 378-80. 6. Ziboh VA, Cohen KA, Ellis CN, et al. Effects of dietary supplementation of fish oil on neutrophil and epidermal fatty acids. Modulation of clinical course of psoriatic subjects. Arch Dermatol 1986; 122: 1277-82. 7. Lassus AL, Dahlgren A-L, Halpern MJ, Sntalahti J, Happonen H-P. Effects of dietary supplementation with polyunsaturated ethyl ester lipids (Angiosan) in patients with psoriasis and psoriatic arthritis.J Int Med Res 1990; 18: 68-73. 1.
