Seasonality in the diagnosis of insulin-dependent diabetes mellitus (IDDM), i.e., increased incidence in winter, was the impetus for this study of seasonality in glycosylated hemoglobin levels in nondiabetics. Glycosylated hemoglobin levels of 35 nondiabetic children and adults were highest at the ends of autumn and winter and lowest at the ends of spring and summer (P < 10−4). This result is consistent with reports of seasonal variation in blood glucose, with the highest levels occurring in winter, as well as reports that suggest an internal milieu of increased counterinsulin action in winter due to seasonality in counterinsulin hormones, dietary factors, body weight, amount of exercise, growth rates in children, and ambient temperature. IDDM is caused by the gradual destruction of the pancreatic insulin-producing cells via lymphocytic infiltration—a process that may occur over years. We conclude that a decreased carbohydrate tolerance associated with winter can explain the seasonal variation in the incidence of IDDM and that this seasonality is caused by the precipitation of overt carbohydrate intolerance in individuals with already seriously compromised insulin secretory capacity. This implies that seasonality is not very informative about the cause of the destruction of pancreatic insulin-producing cells.
Original Articles|
March 01 1987
Seasonality in Glycosylated Hemoglobin in Normal Subjects: Does Seasonal Incidence in Insulin-Dependent Diabetes Suggest Specific Etiology?
Michael J MacDonald;
Michael J MacDonald
Pediatric Diabetes Program, University of Wisconsin Medical School
Madison, Wisconsin
Search for other works by this author on:
Leone Liston;
Leone Liston
Clinical Laboratory, University Hospital
Madison, Wisconsin
Search for other works by this author on:
Ian Carlson
Ian Carlson
Clinical Laboratory, University Hospital
Madison, Wisconsin
Search for other works by this author on:
Address correspondence and reprint requests to Dr. Michael J. MacDonald, University of Wisconsin Medical School, 1300 University Avenue, Room 3459, Madison, Wl 53706.
Diabetes 1987;36(3):265–268
Article history
Received:
April 28 1986
Revision Received:
September 29 1986
Accepted:
September 29 1986
PubMed:
3803736
Citation
Michael J MacDonald, Leone Liston, Ian Carlson; Seasonality in Glycosylated Hemoglobin in Normal Subjects: Does Seasonal Incidence in Insulin-Dependent Diabetes Suggest Specific Etiology?. Diabetes 1 March 1987; 36 (3): 265–268. https://doi.org/10.2337/diab.36.3.265
Download citation file: