There has been no decline in neural tube defects (NTD) in the UK despite campaigns to encourage women to take folic acid supplements prior to conception, say researchers in a letter to the Lancet (1999;354:998). The Health Education Authority (HEA), which has been running one such campaign, said that it was too early to assess the effects of its campaign.
A major Medical Research Council study in 1991 showed that folic acid supplementation reduced the risk of recurrences of NTDs and, in 1992, a UK expert advisory group stated that folic acid could also reduce first occurrence of NTDs. At that time, doctors were urged to encourage women to take folic acid.
Ms Lenore Abramsky (department of medical and community genetics, Imperial College school of medicine, London) and colleagues have collected data from registers of congenital anomalies in England, Scotland and Wales to measure the effectiveness of the HEA campaign, which started in 1996. They also looked at NTD rates since 1991 and, from three registers, from 1980.
They report that there has been no decline in the NTD rate since 1991, even after the HEA campaign. There was a decline during the 1980s, a finding which they say has been noted by other studies, and may be attributable to improved diets or a return to usual occurrence NTD rates following an “epidemic” between 1920 and 1949.
The authors suggest several possible reasons why NTD rates have failed to decline. These include: a lack of awareness of the benefits of folic acid; women failing to take supplements; or women taking folic acid at the wrong time. In addition, some women may not be benefiting from supplementation, they said.
Ms Abramsky told The Journal on September 20 that the study did not specifically investigate these reasons so they were speculation. However, she suspected that the most important reason for women not taking folic acid at the right time was that they did not plan their pregnancies. She suggested that all women of child bearing age should have folic acid supplementation, perhaps through food fortification. In addition, she hoped that warnings to increase awareness of the importance of folic acid could be placed on oral contraceptive and tampon packaging.
The HEA folic acid project manager, Ms Lucy Thorpe, said that the study showed it was important not to be complacent. “We need sustained and persistent campaigning to maintain awareness but we cannot do it alone,” she said. “The support of health professionals is particularly important, they can take every opportunity to promote the message.” In addition, she commented that the HEA was working with the food industry to promote the fortification of breads and breakfast cereals.