[Risk factors related to osteoporosis and age of onset of menopause in the general population].

Objectives: We analyze the risk factors which have an influence on osteoporosis. We study the relationship between the beginning of menopause and both ponderal index and tobacco consumption.
Design: A two-year long prospective study.
Setting: Hortaleza Council Health Center, Madrid.
Patients: 504 women who took part in the Menopause Programa from may 1994 to may of 1996. All of them have had a quantitative computerized tomography.
Measurements: We analyze the following risk factors: family background, tobacco consumption, calcium intake, physical exercise and ponderial index. We studied the risk factors frequency and its relation with osteoporosis. A statistical analysis of that relation has been made. We studied the relationship between both ponderal index and the tobacco consumption and the beginning of menopause.
Main Results: Every risk factor we have studied has an influence on osteoporosis. However the lack of regular physical exercise together with a lower ponderial index seem to be the most outstanding risk factors: p = 0.024 for physical exercise and p = 0.05 for ponderal index. As to the age when menopause begins we have found out that among women who smoked menopause started 1.29 years earlier (p = 0.025). Meanwhile among women with a lower Quetelet rate menopause began 0.95 years earlier.
Conclusions: The risk factors we have studied have an influence on the incidence of osteopenia/osteoporosis. The longer time of amenorrhea, the bigger influence. Prevention programs should start at an earlier age in order to avoid risk factors that depend on the patients behavior. Menopause begins earlier in women who smoke and those who have a lower ponderal index.