In the mid-1980s, a group of researchers in four cities began enrolling patients between the ages of 18 and 30 years in the Coronary Artery Risk Development in Young Adults (CARDIA) study. In the second year of the study, the researchers collected toenail clippings from each patient.1 At the time, they were interested in the role of trace minerals, such as selenium, in the risk of future cardiovascular disease. Most recently, the CARDIA study collected data in 2015-2016, 30 years after the study began. The study has provided information on the association between trace minerals such as zinc, mercury, chromium, and copper and a host of diseases, including cardiovascular disease, gastric cancer, chronic kidney disease, and others. New studies still are being published—all of this from 30-year-old toenail clippings.
Human hair and nails are just patches of dead keratin, either cascading over our otherwise-barren skulls or adhering, lumplike, to the ends of our fingers and toes. While many of us go through life considering these keratin strands and lumps to be nuisances that require regular trimming, snipping, or perhaps plucking, hair and nails can also be indicative of a range of health problems. This edition of FP Essentials reminds us that if the eyes are the windows to the soul, the hair and nails are so much more than ornaments. The living tissues that produce and surround them are subject to injury and disease, and accurate identification and effective management of these conditions can have a tremendous effect on patients’ lives.
Section One of this edition covers the definitions and evaluation of scarring and nonscarring alopecias, and Section Two discusses management of alopecias. Pharmacotherapy, procedural therapies, and other management options all are considered. Section Three addresses the evaluation and management of hypertrichosis and hirsutism. Section Four details common and less common nail conditions, including infections, dystrophies, and color changes.
I hope you find this edition of FP Essentials useful to your practice.
Kate Rowland, MD, FAAFP, Associate Medical Editor
Vice Chair of Education and Associate Professor,
Department of Family Medicine
Rush University, Chicago, Illinois