Hearing impairment and low bone mineral density increase the risk of bone fractures in women with Turner's syndrome.
OBJECTIVE
To assess factors associated with excess rates of fractures in women with Turner's syndrome (TS).


METHODS
History of bone fracture and treatment with oestrogen, growth hormone (GH), oxandrolone and thyroxine, anthropometry, blood measurements of calcium, vitamin D (25-hydroxycholecalciferol), parathyroid hormone and karyotype, pure tone audiometry and spinal bone mineral density (BMD).


RESULTS
One hundred and seventy-seven consecutive women with TS, aged 19-60 years, were interviewed with respect to bone fracture history. BMD and hearing information were recorded from the medical notes. Karyotype was available in 94% of patients (55% monosomy 45X, 45% other X chromosome defects and mosaicism). Subjects had a mean (SD) height of 1.47 (0.07) m and BMI 25.8 (5.2) kg/m(2). The prevalence of fractures was 32% and hearing impairment 84% (18% conductive and 67% sensorineual, of whom 32% and 16%, respectively, used hearing aids). BMD T score was < -1 in 55% of women and < -2.5 in 9%. Fracture rates were higher in subjects with a combination of low BMD and hearing impairment (44% in conductive and 35% in sensorineural) than those with high BMD and normal hearing (25%) (P < 0.05). The duration of oestrogen deficiency was also longer in the former groups (P < 0.05). Multivariate logistic regression analysis (adjusted for age and karyotype) showed that increased risk of fracture was independently associated with low BMD (OR 3.2, 95% CI: 1.0 to10.5) and hearing impairment (conductive: OR 4.8, 95% CI: 1.2 to18.9, sensorineural: OR 3.6, 95% CI: 1.1 to11.8). Subgroup analysis showed that hearing impairment was associated with fractures only in those with low BMD (OR 9.0, 95% CI: 1.1-73.4). Further adjustments for weight, height, BMI, calcium levels, vitamin D concentrations, thyroxine use and oestrogen deficiency, previous use of oxandrolone or GH did not alter these relationships.


CONCLUSIONS
Women with TS who have low BMD and hearing impairment, particularly a conductive type, are at increased risk of bone fractures.
Han
Thang S
TS
Department of Endocrinology, University College London Hospitals, London, UK.
Cadge
Barbara
B
Conway
Gerard S
GS
D015502:Absorptiometry, Photon; D000328:Adult; D001301:Audiometry, Pure-Tone; D015519:Bone Density; D015914:Estrogen Replacement Therapy; D005260:Female; D050723:Fractures, Bone / Q000209:etiology*; D034381:Hearing Loss / Q000150:complications*; D006801:Humans; D016015:Logistic Models; D010024:Osteoporosis / Q000150:complications*; D018570:Risk Assessment / Q000379:methods; D014424:Turner Syndrome / Q000150:complications* / Q000188:drug therapy