NIH research funding does not recognise importance of sex differences

Only 3% of all grants given by the US National Institutes of Health (NIH) have been for research which takes into account that results may differ according to the sex of the research subjects, a new study from the Society for Women's Health Research has shown. The study analysed publicly available abstracts of all institute funded research for the four years 2000-3. It looked at how many of the proposals included “an investigation of sex differences in the research hypothesis or the project specific aims.”

The society wants to see more research into the differences between the sexes, and an increase in research into medical and scientific issues that takes into account the fact that the results of the research may depend upon the sex of the subject. Research into a new drug, for example, must be done with enough subjects of each sex to ensure that the results are applicable to both sexes.

“Every cell has a sex,” said Sherry Marts, the society's vice president for scientific affairs. Whether a cell contains an XX or an XY chromosome may have an impact on everything from regulation of gene expression in a cell line to the efficacy or toxicity of a pharmaceutical in a living human.

Dr Marts was dismayed that the institutes with the largest budgets generally were funding the smallest portion of grants considering questions of sex differences. Just 0.63% of the National Cancer Institute grants considered this question in their fiscal year 2003 budget of $4.6bn (£2.5bn; €3.6bn). Only three of the smallest institutes fell within the 5%-8% funding range that the society believes is adequate for this type of research.

The society recommends, “NIH research guidelines must be updated and modified once again to actively promote sex differences research at all levels, including basic research in cell and tissue culture, the development and study of appropriate animal models and in early stage clinical research, as called for by the [Institute of Medicine].” It said that each institute should create a position to review grant proposals, and offer supplemental grants to investigators to enroll more women in studies and adequately power analysis of sex differences.

The Office of Research on Women's Health should be given greater resources to coordinate and financially support trans-institute research activities, as the Office of AIDS Research does.

Wendy Baldwin coordinated the extramural grants programme at the institutes during the period of the study and currently serves as executive vice president for research at the University of Kentucky. She applauded the society for continuing to draw attention to the issue and for seeking to integrate their interests into the overall research agenda rather than establish a separate institute.

But Dr Baldwin feels that the methodology used in the study does not give an accurate picture of funding patterns at the institutes. It underestimates phase III clinical trials and does not include contract mechanisms, both of which are large programmes many times the size of a typical grant.

Furthermore, NIH funding was expanding rapidly during those years, so a flat percentage of the whole represents a significant increase in the total number of grants awarded in an area.

The report, National Institutes of Health: Intramural and Extramural Support for Research on Sex Differences, 2000-2003, is at www.womenshealthresearch.org/press/CRISPreport.pdf