Objective: To analyze the age at menarche of girls with type 1 diabetes (T1D) who were diagnosed with the disease before puberty and compare it with that of an age-matched group of normal girls. Previous studies on the appearance of menarche showed that the mean age of onset of menarche is delayed in girls affected by T1D compared with normal girls.
Design: Case-control study.
Setting: Patients and controls in an academic research environment.
Patient(s): We studied, retrospectively, the charts of 162 consecutive girls with T1D born in a geographically defined region between 1984 and 1994 with a mean disease duration of 3-5 years, all of whom were on intensive insulin therapy since diagnosis of T1D. The control group consisted of 214 normal girls born between 1984 and 1994, who agreed to fill in an anonymous questionnaire regarding age at menarche and other clinical information.
Intervention(s): There was no intervention per se in the study. Age at menarche appears as a dependent variable of body mass index (BMI), HbA1c, and so on.
Main outcome measure(s): BMI, HbA1c, and duration of T1D at menarche were considered among the potential factors affecting the age of menarche.
Result(s): Age at menarche in girls with T1D was significantly delayed compared with control girls (12.6 +/- 1.5 years vs. 12.25 +/- 1.4 years, respectively). HbA1c levels and BMI did not influence the age at menarche.
Conclusion(s): Despite intensive insulin therapy and good metabolic control since diagnosis of T1D, the age at menarche is still delayed in girls who develop T1D before puberty.