The relationship between daily calcium intake and bone mineral density in men with prostate cancer

Authors


Jacques P. Morin, Urology Department, Vall d’Hebron University Hospital, P. Vall d’Hebrón 119–129, 08035 Barcelona, Spain. e-mail: jplanas@vhebron.net, 34021jpm@comb.es

Abstract

OBJECTIVE

To analyse the relationship between daily calcium intake (DCI) and bone mineral density (BMD) in patients with prostate cancer, and to assess if DCI is a risk factor for osteoporosis in this group of patients.

PATIENTS AND METHODS

DCI was assessed by a standard questionnaire answered by men with prostate cancer who had had bone densitometry. BMD was measured by dual-energy X-ray absorptiometry in the lumbar spine and different hip sites, in a cross-sectional study including 372 men with prostate cancer free of bone metastases, 71.5% (266) under androgen-deprivation therapy (ADT) and 28.5% (106) after radical prostatectomy (RP). Osteoporosis was defined according to the International Society for Clinical Densitometry official position (2005).

RESULTS

A DCI of <1000 mg, the National Institute of Health recommendation, was detected in 93% of the men, (93.5% under ADT and 91.5% after RP). Osteoporosis was identified in 49.2% (183) of the patients, 54.9% (146) under ADT and 34.9% (37) after RP. The mean DCI was 609.7 mg in men with osteoporosis and 682.8 mg in those without (P < 0.001); in men under ADT the mean DCI remained significantly lower in those with osteoporosis (615.5 vs 700.4 mg, P < 0.001). A multivariate analysis showed that DCI was an independent risk factor for osteoporosis, together with patient age, ADT and its duration.

CONCLUSIONS

DCI seems to be related to BMD; a low DCI was an independent risk factor for osteoporosis in men with prostate cancer. In the study population overall the DCI was inadequate. Urologists should recommend a DCI of >1000 mg in patients with prostate cancer, especially in those under ADT.

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