Associations between frailty and serum N-terminal propeptide of type I procollagen and 25-hydroxyvitamin D in older Spanish women: The Toledo Study for Healthy Aging

After adjustment for confounders, high PINP levels (defined by the upper quartile) and low levels of 25(OH)D (lower quartile) remained significantly associated to frailty [OR for PINP: 2.19; OR for 25(OH)D: 1.65]. Women with both high PINP levels and low 25(OH)D levels presented a 5.85-fold increased frailty risk.