Letters to the Editor

Common Causes of Night Sweats in Various Populations

TO THE EDITOR: The article, "Diagnosing Night Sweats,"¹ in American Family Physician was very interesting. While the article discussed many entities, one of the most common reasons for this symptom in women was given very little emphasis. With the population distribution in the United States, perimenopause and menopause are by far the most common cause of night sweats in a primary care population. Many women have discontinued hormone therapy. They also may have night sweats just as they did when they were perimenopausal. Night sweats can contribute to sleep deprivation and mood swings. Night sweats and hot flushes are associated with depression in perimenopausal women.² Night sweats are usually the first menopausal symptom to occur in perimenopausal women. They will occur even before the onset of irregular periods or before follicle-stimulating hormone (FSH) levels become elevated. Thus, the FSH level will not always indicate the etiology of night sweats, unless the woman also has been amenorrheic. Hot flushes and night sweats as symptoms of menopause occur more frequently in black women and in women who have had a surgical menopause.³

Another common cause of night sweats that was not noted in the article¹ is the postpartum state. I have found, based on multiple personal communications with mothers who were breastfeeding, that breastfeeding also results in night sweats. I have been unable to find documentation of the night sweats that occur during nursing in the medical literature or on some of the breastfeeding Web sites, including the La Leche League site (www. lalecheleague.org).

In a study of a primary care population published in 2002,⁴ it was reported that panic attacks are associated with night sweats after controlling for all other examined variables.

There are other medications that can cause night sweats that the authors¹ did not include in Table 4. The package inserts of selective estrogen receptor modulators, such as raloxifene (Evista) and tamoxifen (Nolvadex), list hot flushes and night sweats as a common side effect. With more women needing prevention and/or treatment for osteoporosis and treatment for breast cancer, there will most likely be an increase in the presentation of night sweats. Hot flushes and night sweats with these drugs are worse in the first six months of treatment,⁵ and may be worse in those patients who also have recently stopped hormone therapy. Other drugs associated with night sweats are selective serotonin reuptake inhibitors, antihistamines, and other antidepressants.⁴

ROSLYN D. TAYLOR, M.D.
Memorial Family Practice Residency
1107 E. 66th
Savannah, GA 31404

REFERENCES

1. Viera AJ, Bond MM, Yates SW. Diagnosing night sweats. Am Fam Physician 2003;67:1019-24.
2. Joffe H, Hall JE, Soares CN, Hennen J, Reilly CJ, Carlson K, et al. Vasomotor symptoms are associated with depression in perimenopausal women seeking primary care. Menopause 2002;9:392-8.
3. Avis NE, Stellato R, Crawford S, Bromberger J, Ganz P, Cain V, et al. Is there a menopausal syndrome? Menopausal status and symptoms across racial/ethnic groups. Soc Sci Med 2001;52:345-56.
4. Mold JW, Mathew MK, Belgore S, DeHaven M. Prevalence of night sweats in primary care patients: an OKPRN and TAFP-Net collaborative study. J Fam Pract 2002;51:452-6.
5. Glusman JE, Huster WJ, Paul S. Raloxifene effects on vasomotor and other climacteric symptoms in postmenopausal women. Prim Care Update Ob Gyns 1998;5:166.

Diagnosing Night Sweats Requires Clear Definition

TO THE EDITOR: The article, "Diagnosing Night Sweats,"¹ was based on a MEDLINE literature review from 1966 to July 2001. As a result, the authors' literature search missed our study² of the epidemiology of night sweats in primary care that was published in 2002. There also has been at least one other relevant epidemiologic study³ that was not mentioned in their article.¹

Based on our published and unpublished results, it appears that the classic definition of night sweats "does not describe the majority of patients who may complain of the symptom."² Night sweats are commonly experienced by primary care patients who, for unclear reasons, rarely mention them to their primary care physician even when they become severe and bothersome. The most common causes of night sweats have yet to be elucidated and, therefore, the appropriate evaluation of patients with this symptom is unclear. Given the level of our collective ignorance, many of the recommendations made by the authors¹ seem reasonable, however.

JAMES W. MOLD, M.D., M.P.H.
The University of Oklahoma Health Sciences Center
P.O. Box 26901
900 Northeast 10th St.
Oklahoma City, OK 73190

REFERENCES

1. Viera AJ, Bond MM, Yates SW. Diagnosing night sweats. Am Fam Physician 2003;67:1019-24.
2. Mold JW, Mathew MK, Belgore S, DeHaven M. Prevalence of night sweats in primary care patients: an OKPRN and TAFP-Net collaborative study. J Fam Pract 2002;51:452-6.
3. Lea MJ, Aber RC. Descriptive epidemiology of night sweats upon admission to a university hospital. South Med J 1985;78:1065-7.

IN REPLY: We would like to thank Dr. Mold for his comments and appreciate the study¹ conducted by him and his colleagues on the prevalence of night sweats in primary care patients. When we conducted the research for our article and revised it, that study was not yet published. An informal survey of medical students, house officers, and senior physicians (including infectious disease specialists, oncologists, and generalists) found that tuberculosis is the first disease to come to mind when a patient reports night sweats.² The same pool of physicians and students reported that they rarely encountered night sweats as a symptom among patients with tuberculosis. In our original manuscript,³ we cited the study⁴ by Lea and Aber that discussed the descriptive epidemiology of night sweats, but that section was subsequently edited out of the final article. This study⁴ reported that out of 174 randomly selected university hospital patients, 72 reported night sweats within three months before admission. None of these patients had tuberculosis. These observations that many possible common causes of night sweats were not known served as the initial basis for our article.

ANTHONY J. VIERA, LCDR, MC, USNR
Naval Hospital Jacksonville
Family Practice Department
2080 Child St.
Jacksonville, FL 32214-5005

REFERENCES

1. 1. Mold JW, Mathew MK, Belgore S, DeHaven M. Prevalence of night sweats in primary care patients: an OKPRN and TAFP-Net collaborative study. J Fam Pract 2002;51:452-6.
2. 2. Fred HL. Night sweats. Hosp Pract (Off Ed) 1993;28:88.
3. 3. Viera AJ, Bond MM, Yates SW. Diagnosing night sweats. Am Fam Physician 2003;67:1019-24.
4. 4. Lea MJ, Aber RC. Descriptive epidemiology of night sweats upon admission to a university hospital. South Med J 1985;78:1065-7.

Correction

The article "Evaluation of the Subfertile Man" (May 15, 2003, page 2165) contained an error regarding the size of a normal testis. On page 2167, in the second column, second line, the size of a normal testis should be 20 cm³ or more, or at least 4 cm in greatest dimension. The online version of this article has been corrected.

Send letters to Jay Siwek, M.D., Editor, American Family Physician, 11400 Tomahawk Creek Pkwy., Leawood, KS 66211-2672; fax: 913-906-6080; e-mail: afplet@aafp.org. Please include your complete address, telephone number, and fax number. Letters should be submitted on disk, double-spaced, fewer than 500 words, and limited to one table or figure and six references. Please submit a word count. Letters submitted for publication in AFP must not be submitted to any other publication. Possible conflicts of interest must be disclosed at time of submission. Submission of a letter will be construed as granting the AAFP permission to publish the letter in any of its publications in any form. The editors may edit letters to meet style and space requirements.