Smoking is a risk factor for decreased physical performance in elderly women.

Background: In 487 elderly women aged 65-77 years, we examined the association of smoking with physical performance measures of muscle function and whether the effect of smoking on physical performance measures is mediated through its effect on vitamin D or estrogen metabolism.

Methods: Timed rise, timed walk at normal and fast speed, grip strength, and serum biochemical measurements were compared between smokers, past smokers, and nonsmokers. Analysis of covariance was used to compare physical performance variables while adjusting for confounding variables.

Falls are associated with decreased renal function and insufficient calcitriol production by the kidney.

In a double blind placebo controlled 3-year osteoporosis study in elderly women, we collected prospective data on falls. The study population comprised 489 normal elderly women aged 65-77 years randomized to four groups: placebo, calcitriol 0.25 mcg b.

Caffeine decreases vitamin D receptor protein expression and 1,25(OH)2D3 stimulated alkaline phosphatase activity in human osteoblast cells.

Of the various risk factors contributing to osteoporosis, dietary/lifestyle factors are important. In a clinical study we reported that women with caffeine intakes >300 mg/day had higher bone loss and women with vitamin D receptor (VDR) variant, tt were at a greater risk for this deleterious effect of caffeine. However, the mechanism of how caffeine effects bone metabolism is not clear.

An age-related decrease in creatinine clearance is associated with an increase in number of falls in untreated women but not in women receiving calcitriol treatment.

Context: Decreased calcitriol production due to impaired renal function may be a significant risk factor for falls in normal aging population.

Objective: The objective of the study was to examine the association between creatinine clearance (CrCl) and the incidence of falls and fallers in groups treated with placebo, calcitriol, estrogen therapy (ET)/estrogen + progestin therapy (HT), and calcitriol + ET/HT.

Design: This was a 3-yr, double-blind, placebo-controlled study designed to test the efficacy of calcitriol and ET/HT on bone loss and falls with analysis by intention to treat and post hoc.

Estrogen receptor alpha gene polymorphisms are associated with changes in bone remodeling markers and treatment response to estrogen.

Objectives: Association studies between estrogen receptor alpha (ERalpha) gene polymorphisms and bone mineral density (BMD) have yielded inconsistent results. In the present study we evaluated the influence of XbaI and PvuII ERalpha gene polymorphisms on BMD, biochemical markers, rates of bone loss and the response to estrogen/hormone therapy (ET/HT) in elderly postmenopausal women.

Methods: At baseline, we measured the association between ERalpha genotypes and BMD and biochemical markers in 489 elderly women, mean age 71 +/- 3 years.