by clicking the arrows at the side of the page, or by using the toolbar.
by clicking anywhere on the page.
by dragging the page around when zoomed in.
by clicking anywhere on the page when zoomed in.
web sites or send emails by clicking on hyperlinks.
Email this page to a friend
Search this issue
Index - jump to page or section
Archive - view past issues
Australian Journal of Pharmacy : May 2008
education current drug information antioxidants have little or no effect in primary prevention of Md a ge-related macular degeneration (AMD) is the leading cause of severe visual loss in people aged older than 50 in the developed world. A number of treatments are available but they are suitable only for the small proportion of people with ‘wet’ AMD. No treatments are available for the ‘dry’ form. There is little to offer for the primary prevention of age-related macular degeneration (AMD) in older people. Some studies indicate that diets rich in antioxidants may protect against the development of signs of early AMD, and the common perception is that a diet rich in antioxidants can protect against AMD. An extensive systematic review and meta-analysis of the role of a range of dietary antioxidants— vitamins A, C, and E; zinc; lutein and zeaxanthin; alpha-carotene; beta-carotene; beta-cryptoxanthin; and lycopene—in the primary prevention of AMD was carried out.1 Only randomised clinical trials and prospective cohort studies were included. Two reviewers independently searched the databases and selected the studies, using standardised criteria. Randomised clinical trials and prospective cohort studies were included. Twelve studies (nine prospective cohort studies and three randomised clinical trials) were included. Data extraction and study quality evaluation were independently reviewed, using standardised criteria. Results were pooled quantitatively using meta- analytic methods. 90 The nine prospective cohort studies included 149,203 people, with 1,878 incident cases of early AMD. The antioxidants investigated differed across studies, and not all studies contributed to the meta- analysis of each antioxidant. When results were pooled, the prospective studies showed that people with relatively high dietary intakes of antioxidants (such as vitamin A, vitamin C, vitamin E, zinc, lutein, zeaxanthin, alpha-carotene, beta-carotene, beta-cryptoxanthin and lycopene) were no more or less likely to develop AMD than those with relatively low intakes. The three randomised clinical trials did not show that antioxidant supplements prevented early AMD. Data from studies that evaluated dietary vitamin E suggested a high intake was associated with a reduced risk of AMD but the two randomised controlled trials, of reasonable quality, indicated that neither vitamin E nor beta-carotene supplements prevent AMD. It concluded: ‘Dietary intake of nine antioxidants evaluated in this systematic review had little or no effect in the primary prevention of early AMD in well nourished Western populations. There is insufficient evidence that antioxidants supplements prevent the onset of AMD. Cigarette smoking remains the only widely accepted modifiable risk factor for the primary prevention of AMD, and patients seeking advice on AMD prevention should be encouraged to stop smoking’. n 1. chong eW-t, Wong tY, Kreis aJ, Simpson Ja, guymer rH. dietary antioxidants and primary prevention of age related macular degeneration: systematic review and meta- analysis. BmJ 2007;335:755. Falls decreased following review of drugs associated with risk several drugs are associated with an increased risk of falls. A prospective cohort study of i geriatric outpatients (older than 65 years) was carried out to identify differences in the incidence of falls after withdrawal (discontinuation or dose reduction) of fall-risk-increasing drugs as a single intervention.1 One hundred and thirty-nine patients presenting with one or more falls during the previous year were included. Fall-risk-increasing drugs were withdrawn, if possible, and the incidence of falls was assessed within two months of follow-up, after a set one month period of drug withdrawal. tHe auStralian Journal of PHarmacY Vol.89 maY 2008 In 67 patients, it was possible to discontinue a drug that increased the risk of falls, and in eight patients to reduce its dose. The total number of fall incidents during follow-up was significantly lower in these 75 patients, than in those who continued treatment t is well known that falls in older people are a frequent and and serious problem and that (mean number of falls: 0.3 vs. 3.6). The hazard ratio of a fall during the two-month follow-up was 0.48 for overall drug withdrawal; 0.35 for cardiovascular drug withdrawal and 0.56 for psychotropic drug withdrawal; after adjustment for age, gender; use of fall-risk-increasing drugs; baseline falls frequency; and reason for referral. It was concluded: ‘Withdrawal of fall-risk-increasing drugs appears to be effective as a single intervention for falls prevention in a geriatric outpatient setting. The effect was greatest for withdrawal of cardiovascular drugs’. n 1. van der Velde n, Stricker BH, Pols Ha, van der cammen tJ. risk of falls after withdrawal of fall- risk-increasing drugs: a prospective cohort study. Br J clin Pharmacol 2007;63:232–7.