The top 100 cited cholesterol papers

1.Introduction

2016 is the 200th anniversary of the naming of cholesterol [1] and as part of the special issue of Biomedical Spectroscopy and Imaging to mark this milestone, this article presents an analysis of the most cited articles on cholesterol in an attempt to identify the most widely read and influential articles on the subject and give the authors the recognition they deserve. Such an analysis of cited papers can also identify trends, provide guidance for future research and highlight where there are insufficiencies in the current literature [1,2].

2.Methods and limitations

As with many areas of biomedicine, the field of cholesterol research historically has had a strong divide between biochemical and physiological investigations. As we began the process of selecting the 100-most-cited papers in the field this divide was in clear evidence. Most of the papers fell into one of the following categories:

While the major interest of the journal is in the fifth category we felt it would also be interesting to look at the wider picture to mark this anniversary. Citation data are not readily available for papers published more than 100 years ago and for this reason we focused on the last 100 years and also, for comparison the last 10 years.

It is important to recognize that any search strategy represents an approximation to the field.

The data used in the tabulation of each originate from the Web of Science Core Collection database which includes but is not limited to all papers indexed by the NIH’s Medline database. Two selection filters were used to determine which papers would contribute to an article’s metrics. The first requirement was that all papers to be included in the analysis contained the search term “cholesterol” in the title field. Reviews were included in the analysis because, while it is relatively “easy” to write a review, it is very difficult to write a review that is well cited. Well-cited reviews tend to be authored by leaders in the field and present conceptual advances or new hypotheses that can be as important as experimental advances.

The second filter is temporal: only papers published and subsequently indexed in Web of Science Core Collection between January 1, 1916 and December 31, 2015 were considered for the 100 year analysis and only papers published and subsequently indexed in Web of Science Core Collection between January 1, 2006 and December 31, 2015 were considered for the 10 year analysis. The queries for the two document sets were conducted on February 2, 2016 and March 29, 2016 respectively.

It is important to recognize that citation scores are, by necessity, close approximations rather than absolute values, the latter not being possible because all citation tools have slightly different variables (e.g. journals indexed, time period covered, data reliability).

3.Results

4.Discussion

It is interesting to see the preponderance of different sub-disciplines in cholesterol research represented in Tables 1 and 2. In particular, the most cited articles over last 10 years shows a shift away from articles describing methods for the measurement of cholesterol towards (increasingly molecular) studies describing cholesterol metabolism/homeostasis, the role of cholesterol in diseases, and cholesterol-lowering drugs, compared with the most cited articles from the last 100 years. We hypothesize that the complete lack of the cholesterol measurement category in the top-100 list of the last decade, as can be seen in Table 4, indicates that while incremental improvements in this area have continued over the last ten years, there has been nothing which one could easily classify as a “quantum leap” producing a highly-cited landmark paper. By contrast, the papers cited in Table 2 suggest that the last 10 years have witnessed the advent of studies describing the role of cholesterol in non-cardiovascular diseases such as cancer (the second reference numbered 69) and Alzheimer’s (the second reference numbered 76 and 94). When comparing Tables 3 and 4, another salient feature is the dominance one observes in the most recent period of cardiovascular journals. By comparing the top-10 journals based on number of papers in each of the top-100 articles lists in Tables 3 and 4, one can observe past dominance of journals of a more general nature such as Clinical Chemistry, British Medical Journal, and Science being displaced through the introduction of the Journal of the American College of Cardiology and Circulation Research into the top ten. Also of note is that Circulation rose in the ranking from #6 to #2 when considering the most-cited papers of the last decade instead of the last century.

Some of the names in Table 1 will be clearly recognized by the majority of cholesterol research investigators as being “superstars”. For example the team of Michael S. Brown and Joseph L. Goldstein, who were awarded the 1985 Nobel prize for Physiology or Medicine 1985 for their work on the regulation of cholesterol metabolism, are jointly authors of nine papers in the most cited articles of the last century (Table 1, numbers 8, 18, 21, 23, 24, 45, 63, 67 and 69) and three from the most cited of the last 10 years (Table 2, numbers 65, 74 and the second reference numbered 87). Other names, especially in Table 2 are “rising stars” who, in the last decade, have made significant contributions to the cholesterol research literature.